Publications by authors named "John D Hughes"

29 Publications

  • Page 1 of 1

Post-traumatic stress disorder is associated with alterations in evoked cortical activation during visual recognition of scenes.

Neuroimage Clin 2021 3;31:102752. Epub 2021 Jul 3.

National Intrepid Center of Excellence, Walter Reed National Military Medical Center, Bethesda, MD, USA; Behavioral Biology Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA. Electronic address:

We recorded magnetoencephalography data during a visual recognition task in participants with combat exposure (n = 40, age: 41.2 ± 7.2 years) to investigate the relationship between the evoked brain activity, behavioral performance, and the severity of their post-traumatic stress symptoms assessed using the PTSD Check List for DSM V version (PCL-5). In an initial study session, participants were presented with a series of images of outdoor scenes and were instructed to study the images for an upcoming recognition test. In a subsequent session, the original images were shown intermixed with novel images while participants performed the recognition task. PCL-5 scores were negatively correlated with discrimination performance and with the recognition accuracy for original images. During the recognition session, higher PCL-5 scores were associated with reduced relative power of the evoked response to original images from 100 ms to 300 ms following the image onset over a distributed brain network including the bilateral inferior frontal gyri, left middle frontal gyrus, left supramarginal gyrus, right precuneus and the bilateral superior temporal gyri. These findings indicate that the lower recognition performance in participants with higher PTSD symptom severity is associated with altered cortical activity in brain regions that are known to play a role in the elaboration on visual cues that supports recollection.
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http://dx.doi.org/10.1016/j.nicl.2021.102752DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC8313740PMC
September 2021

Functional and Structural Neuroimaging Correlates of Repetitive Low-Level Blast Exposure in Career Breachers.

J Neurotrauma 2020 12 30;37(23):2468-2481. Epub 2020 Sep 30.

Operational and Undersea Medicine Directorate, Naval Medical Research Center, Silver Spring, Maryland, USA.

Combat military and civilian law enforcement personnel may be exposed to repetitive low-intensity blast events during training and operations. Persons who use explosives to gain entry (i.e., breach) into buildings are known as "breachers" or dynamic entry personnel. Breachers operate under the guidance of established safety protocols, but despite these precautions, breachers who are exposed to low-level blast throughout their careers frequently report performance deficits and symptoms to healthcare providers. Although little is known about the etiology linking blast exposure to clinical symptoms in humans, animal studies demonstrate network-level changes in brain function, alterations in brain morphology, vascular and inflammatory changes, hearing loss, and even alterations in gene expression after repeated blast exposure. To explore whether similar effects occur in humans, we collected a comprehensive data battery from 20 experienced breachers exposed to blast throughout their careers and 14 military and law enforcement controls. This battery included neuropsychological assessments, blood biomarkers, and magnetic resonance imaging measures, including cortical thickness, diffusion tensor imaging of white matter, functional connectivity, and perfusion. To better understand the relationship between repetitive low-level blast exposure and behavioral and imaging differences in humans, we analyzed the data using similarity-driven multi-view linear reconstruction (SiMLR). SiMLR is specifically designed for multiple modality statistical integration using dimensionality-reduction techniques for studies with high-dimensional, yet sparse, data (i.e., low number of subjects and many data per subject). We identify significant group effects in these data spanning brain structure, function, and blood biomarkers.
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http://dx.doi.org/10.1089/neu.2020.7141DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7703399PMC
December 2020

Altered modulation of beta band oscillations during memory encoding is predictive of lower subsequent recognition performance in post-traumatic stress disorder.

Neuroimage Clin 2020 27;25:102154. Epub 2019 Dec 27.

National Intrepid Center of Excellence, Walter Reed National Military Medical Center, Bethesda, MD, United States; Behavioral Biology Branch, Walter Reed Army Institute of Research, 503 Robert Grant Ave, Silver Spring, MD 20910, United States. Electronic address:

We studied the relationship between electrophysiological markers of memory encoding, subsequent recognition performance, and severity of PTSD symptoms in service members with combat exposure (n = 40, age: 41.2 ± 7.2 years) and various levels of PTSD symptom severity assessed using the PTSD Check List for DSM V version (PCL-5). Brain activity was recorded using magnetoencephalography during a serial presentation of 86 images of outdoor scenes that were studied by participants for an upcoming recognition test. In a second session, the original images were shown intermixed with an equal number of novel images while participants performed the recognition task. Participants recognized 76.0% ± 12.1% of the original images and correctly categorized as novel 89.9% ± 7.0% of the novel images. A negative correlation was present between PCL-5 scores and discrimination performance (Spearman r = -0.38, p = 0.016). PCL-5 scores were also negatively correlated with the recognition accuracy for original images (r = -0.37, p = 0.02). Increases in theta and gamma power and decreases in alpha and beta power were observed over distributed brain networks during memory encoding. Higher PCL-5 scores were associated with less suppression of beta band power in bilateral ventral and medial temporal regions and in the left orbitofrontal cortex. These regions also showed positive correlations between the magnitude of suppression of beta power during encoding and subsequent recognition accuracy. These findings indicate that the lower recognition performance in participants with greater PTSD symptom severity may be due in part to ineffective encoding reflected in altered modulation of beta band oscillatory activity.
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http://dx.doi.org/10.1016/j.nicl.2019.102154DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC6965746PMC
December 2020

Post-traumatic stress disorder is associated with altered modulation of prefrontal alpha band oscillations during working memory.

Clin Neurophysiol 2019 10 12;130(10):1869-1881. Epub 2019 Jul 12.

National Intrepid Center of Excellence, Walter Reed National Military Medical Center, Bethesda, MD, USA; Behavioral Biology Branch, Walter Reed Army Institute of Research, Silver Spring, MD, USA. Electronic address:

Objective: To investigate the relationship between the severity of PTSD symptoms, modulation of alpha band oscillations, and behavioral performance in a working memory task.

Methods: Magnetoencephalography data were recorded in 35 participants with combat exposure and various degrees of PTSD symptom severity while they performed a modified Sternberg working memory task: briefly presented sets of two or six letters had to be held in memory and participants indicated whether subsequent probe letters were present or absent from these sets.

Results: PTSD scores were positively correlated with the false positive rate in the high memory load condition. Higher rates of false recognition were associated with negative probes that were seen in recent previous trials (negative probe recency effect) or were physically similar with the list letters. The relative alpha band power in the left middle frontal gyrus was negatively correlated with both PTSD scores and false positive rates.

Conclusions: Reduced task specific modulation of alpha band oscillations in left middle frontal cortex may reflect alterations in the functions of pattern separation and suppression of memory traces for irrelevant or no longer relevant information in PTSD.

Significance: The lower amplitude of prefrontal alpha band oscillations may represent an important physiological basis for core PTSD symptoms and can provide a target for interventions to augment response to treatment.
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http://dx.doi.org/10.1016/j.clinph.2019.06.227DOI Listing
October 2019

Activation of dominant hemisphere association cortex during naming as a function of cognitive performance in mild traumatic brain injury: Insights into mechanisms of lexical access.

Neuroimage Clin 2017 23;15:741-752. Epub 2017 Jun 23.

National Intrepid Center of Excellence, Walter Reed National Military Medical Center, Bethesda, MD, USA.

Patients with a history of mild traumatic brain injury (mTBI) and objective cognitive deficits frequently experience word finding difficulties in normal conversation. We sought to improve our understanding of this phenomenon by determining if the scores on standardized cognitive testing are correlated with measures of brain activity evoked in a word retrieval task (confrontational picture naming). The study participants ( = 57) were military service members with a history of mTBI. The General Memory Index (GMI) determined after administration of the Rivermead Behavioral Memory Test, Third Edition, was used to assign subjects to three groups: low cognitive performance (Group 1: GMI ≤ 87,  = 18), intermediate cognitive performance (Group 2: 88 ≤ GMI ≤ 99,  = 18), and high cognitive performance (Group 3: GMI ≥ 100,  = 21). Magnetoencephalography data were recorded while participants named eighty pictures of common objects. Group differences in evoked cortical activity were observed relatively early (within 200 ms from picture onset) over a distributed network of left hemisphere cortical regions including the , the and , the and posterior part of the , and the and . Differences were also present in bilateral and , and in the . All differences reflected a lower amplitude of the evoked responses for Group 1 relative to Groups 2 and 3. These findings may indicate weak afferent inputs and an extended cortical network including association cortex of the dominant hemisphere in patients with low cognitive performance. The association between word finding difficulties and low cognitive performance may therefore be the result of a diffuse pathophysiological process affecting distributed neuronal networks serving a wide range of cognitive processes. These findings also provide support for a parallel processing model of lexical access.
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http://dx.doi.org/10.1016/j.nicl.2017.06.029DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5491489PMC
April 2018

Reduced prefrontal MEG alpha-band power in mild traumatic brain injury with associated posttraumatic stress disorder symptoms.

Clin Neurophysiol 2016 09 17;127(9):3075-3085. Epub 2016 Jun 17.

National Intrepid Center of Excellence, Walter Reed National Military Medical Center, Bethesda, MD, USA.

Objective: To determine if changes in cortical alpha-band power in patients with mild traumatic brain injury (mTBI) are associated with the severity of their post-traumatic stress disorder (PTSD) symptoms, and if injury severity and level of exposure to psychologically traumatic events are predictors of these electrophysiological changes.

Methods: Resting-state magnetoencephalographic recordings were analyzed in 32 patients with mTBI. Alpha-band power was estimated for each patient in 68 cortical regions and was compared between groups of patients with low versus high PTSD symptoms severity.

Results: Participants with high PTSD symptom severity showed reduced alpha-band power bilaterally in the superior and middle frontal gyri and frontal poles, and in the left inferior frontal gyrus. Alpha-band power in bilateral middle frontal gyri and frontal poles was negatively correlated with scores reflecting symptoms of emotional numbing. Loss of consciousness (LOC) associated with mTBI and level of exposure to psychologically traumatic events were predictors of decreased prefrontal alpha-band power in some of these regions.

Conclusion: Altered prefrontal alpha-band activity, shown to be partly explained by mTBI-related LOC, is associated with PTSD symptoms severity.

Significance: Our findings will guide future studies addressing the electrophysiological mechanisms underlying a higher incidence of PTSD in patients with mTBI.
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http://dx.doi.org/10.1016/j.clinph.2016.06.004DOI Listing
September 2016

The influence of do-not-resuscitate status on the outcomes of patients undergoing emergency vascular operations.

J Vasc Surg 2015 Jun 19;61(6):1538-42. Epub 2015 Feb 19.

Division of Vascular and Endovascular Surgery, University of Arizona Medical Center, Tucson, Ariz.

Background: Do-not-resuscitate (DNR) orders allow patients to communicate their wishes regarding cardiopulmonary resuscitation. Although DNR status may influence physician decision making regarding resuscitation, the effect of DNR status on outcomes of patients undergoing emergency vascular operation remains unknown. The aim of this study was to analyze the effect of DNR status on the outcomes of emergency vascular surgery.

Methods: The National Surgical Quality Improvement Program database was queried to identify all patients requiring emergency vascular surgical interventions between 2005 and 2010. Demographics, clinical data, and outcomes were extracted. Patients were compared according to DNR status. The primary outcome measure was 30-day mortality.

Results: During the study period, 16,678 patients underwent emergency vascular operations (10.8% of the total vascular surgery population). Of those, 548 patients (3.3%) had a DNR status. The differences in rates of open or endovascular repair or of intraoperative blood requirement between the two groups were not significant. After adjusting for differences in demographics and clinical data, DNR patients were more likely to have higher rates of graft failure (8.7% vs 2.4%; adjusted P < .01) and failure to wean from mechanical ventilation (14.9 % vs 9.9%; adjusted P < .001). DNR status was associated with a 2.5-fold rise in 30-day mortality (35.0% vs 14.0%; 95% confidence interval, 1.7-2.9; adjusted P < .001).

Conclusions: The presence of a DNR order was independently associated with mortality. Patient and family counseling on surgical expectations before emergency vascular operations is warranted because the risks of perioperative events are significantly elevated when a DNR order exists.
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http://dx.doi.org/10.1016/j.jvs.2014.11.087DOI Listing
June 2015

Traumatic brain injury detection using electrophysiological methods.

Front Hum Neurosci 2015 4;9:11. Epub 2015 Feb 4.

Booz Allen Hamilton Inc. , McLean, VA , USA.

Measuring neuronal activity with electrophysiological methods may be useful in detecting neurological dysfunctions, such as mild traumatic brain injury (mTBI). This approach may be particularly valuable for rapid detection in at-risk populations including military service members and athletes. Electrophysiological methods, such as quantitative electroencephalography (qEEG) and recording event-related potentials (ERPs) may be promising; however, the field is nascent and significant controversy exists on the efficacy and accuracy of the approaches as diagnostic tools. For example, the specific measures derived from an electroencephalogram (EEG) that are most suitable as markers of dysfunction have not been clearly established. A study was conducted to summarize and evaluate the statistical rigor of evidence on the overall utility of qEEG as an mTBI detection tool. The analysis evaluated qEEG measures/parameters that may be most suitable as fieldable diagnostic tools, identified other types of EEG measures and analysis methods of promise, recommended specific measures and analysis methods for further development as mTBI detection tools, identified research gaps in the field, and recommended future research and development thrust areas. The qEEG study group formed the following conclusions: (1) Individual qEEG measures provide limited diagnostic utility for mTBI. However, many measures can be important features of qEEG discriminant functions, which do show significant promise as mTBI detection tools. (2) ERPs offer utility in mTBI detection. In fact, evidence indicates that ERPs can identify abnormalities in cases where EEGs alone are non-disclosing. (3) The standard mathematical procedures used in the characterization of mTBI EEGs should be expanded to incorporate newer methods of analysis including non-linear dynamical analysis, complexity measures, analysis of causal interactions, graph theory, and information dynamics. (4) Reports of high specificity in qEEG evaluations of TBI must be interpreted with care. High specificities have been reported in carefully constructed clinical studies in which healthy controls were compared against a carefully selected TBI population. The published literature indicates, however, that similar abnormalities in qEEG measures are observed in other neuropsychiatric disorders. While it may be possible to distinguish a clinical patient from a healthy control participant with this technology, these measures are unlikely to discriminate between, for example, major depressive disorder, bipolar disorder, or TBI. The specificities observed in these clinical studies may well be lost in real world clinical practice. (5) The absence of specificity does not preclude clinical utility. The possibility of use as a longitudinal measure of treatment response remains. However, efficacy as a longitudinal clinical measure does require acceptable test-retest reliability. To date, very few test-retest reliability studies have been published with qEEG data obtained from TBI patients or from healthy controls. This is a particular concern because high variability is a known characteristic of the injured central nervous system.
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http://dx.doi.org/10.3389/fnhum.2015.00011DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4316720PMC
February 2015

Outcomes of endovascular management of acute thoracic aortic emergencies in an academic level 1 trauma center.

Am J Surg 2014 Dec 22;208(6):974-80; discussion 979-80. Epub 2014 Sep 22.

Division of Vascular and Endovascular Surgery, Department of Surgery, University of Arizona, 1501 North Campbell Avenue, PO Box 245072, Tucson, AZ 85724-5072, USA. Electronic address:

Background: Thoracic aortic emergencies account for 10% of thoracic-related admissions in the United States and remain associated with high morbidity and mortality rates. Open repair has declined owing to the emergence of thoracic endovascular aortic repair (TEVAR), but data on emergency TEVAR use for acute aortic pathology remain limited. We therefore reviewed our experience.

Methods: We retrospectively evaluated emergency descending thoracic aortic endovascular interventions performed at a single academic level 1 trauma center between January 2005 and August 2013 including all cases of traumatic aortic injury, ruptured descending thoracic aneurysm, penetrating atherosclerotic ulcer, aortoenteric fistula, and acute complicated type B dissection. Demographics, clinical data, and outcomes were extracted. Stepwise logistic regression was used to identify independent risk factors for death.

Results: During the study period, 51 patients underwent TEVAR; 22 cases (43.1%) were performed emergently (11 patients [50.0%] traumatic aortic injury; 4 [18.2%] ruptured descending thoracic aneurysm; 4 [18.2%] complicated type B dissection; 2 [9.1%] penetrating aortic ulcer; and 1 [4.5%] aortoenteric fistula). Overall, 72.7% (n = 16) were male with a mean age of 54.8 ± 15.9 years. Nineteen patients (86.4%) required only a single TEVAR procedure, whereas 2 (9.1%) required additional endovascular therapy, and 1 (4.5%) open thoracotomy. Four traumatic aortic injury patients required exploratory laparotomy for concomitant intra-abdominal injuries. During a mean hospital length of stay of 18.9 days (range, 1 to 76 days), 3 patients (13.6%) developed major complications. In-hospital mortality was 27.2%, consisting of 6 deaths from traumatic brain injury (1); exsanguination in the operating room before repair could be achieved (2); bowel ischemia (1) and multisystem organ failure (1); and family withdrawal of care (1). A stepwise logistic regression model identified 24-hour packed red blood cell requirements ≥4 units, admission mean arterial pressure <60 mm Hg, and 24-hour fresh frozen plasma to packed red blood cell (pRBC) ratio <1:1.5 as independent risk factors for death in this cohort. During a mean follow-up of 369 days (range, 35 to 957 days), no subsequent major complications or deaths occurred. All patients underwent serial computed tomographic angiography surveillance, and no device-related problems were identified during intermediate follow-up.

Conclusions: Thoracic aortic emergencies remain challenging. Our experience in a moderate-volume center supports the utilization of TEVAR in the acute setting. Twenty-four-hour pRBC requirements ≥4 units, admission mean arterial pressure <60 mm Hg, and 24 hour fresh frozen plasma to pRBC ratio <1:1.5 were independently associated with death.
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http://dx.doi.org/10.1016/j.amjsurg.2014.08.008DOI Listing
December 2014

Trends and outcomes of endovascular therapy in the management of civilian vascular injuries.

J Vasc Surg 2014 Nov 26;60(5):1297-1307.e1. Epub 2014 Jun 26.

Division of Vascular and Endovascular Surgery, University of Arizona, Tucson, Ariz. Electronic address:

Objective: The rapid evolution of endovascular surgery has greatly expanded management options for a wide variety of vascular diseases. Endovascular therapy provides a less invasive alternative to open surgery for critically ill patients who have sustained arterial injuries. The purpose of this study was to evaluate recent trends in the management of arterial injuries in the United States with specific reference to the use of endovascular strategies and to examine the outcomes of endovascular vs open therapy for the treatment of civilian arterial traumatic injuries.

Methods: A 9-year analysis of the National Trauma Data Bank was performed to identify all patients who sustained arterial injuries. Demographics, clinical data, interventions, and outcomes were extracted. Propensity scores were used to match endovascular patients to those undergoing open operation. Patient outcomes were compared according to treatment approach.

Results: A total of 23,105 patients were available for analysis. Overall, there was a significant increase in the use of endovascular procedures during 9 years (from 0.3% in 2002 to 9.0% in 2010; P < .001), particularly among blunt trauma patients (from 0.4% in 2002 to 13.2% in 2010; P < .001). This increase was noteworthy and dramatic for injuries of the internal iliac artery (from 8.0% in 2002 to 40.3% in 2010; P < .001), thoracic aorta (from 0.5% in 2002 to 21.9% in 2010; P < .001), and common/external iliac arteries (from 0.4% in 2002 to 20.4% in 2010; P < .001). A significant decrease was noted for open procedures (49.1% in 2002 to 45.6%; P < .001), especially for blunt trauma (42.9% in 2002 to 35.8% in 2010; P < .001). There was a stepwise increase in the proportion of patients managed by endovascular therapy as the Injury Severity Score increased (highest in the spectrum Injury Severity Score 31-50). When outcomes were compared between matched patients who underwent endovascular and open procedures, patients who underwent endovascular procedures had significantly lower in-hospital mortality (12.9% vs 22.4%; odds ratio, 0.5; 95% confidence interval, 0.4-0.6; P < .001). Endovascular patients also had decreased rates of sepsis (7.5% vs 5.4%; odds ratio, 0.7; 95% confidence interval, 0.5-0.9; P = .025).

Conclusions: The use of endovascular therapy in the United States has increased dramatically during the last decade, in particular among severely injured blunt trauma patients. Endovascular therapy was associated with improved in-hospital mortality and lower rates of sepsis.
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http://dx.doi.org/10.1016/j.jvs.2014.05.028DOI Listing
November 2014

The natural history of duplex-detected stenosis after femoropopliteal endovascular therapy suggests questionable clinical utility of routine duplex surveillance.

J Vasc Surg 2012 Feb 5;55(2):346-52. Epub 2011 Oct 5.

Division of Vascular and Endovascular Surgery, University of Arizona Health Sciences Center, Tucson, AZ 85724, USA.

Objective: Duplex ultrasound (DU) surveillance (DUS) criteria for vein graft stenosis and thresholds for reintervention are well established. The natural history of DU-detected stenosis and the threshold criteria for reintervention in patients undergoing endovascular therapy (EVT) of the femoropopliteal system have yet to be determined. We report an analysis of routine DUS after infrainguinal EVT.

Methods: Consecutive patients undergoing EVT of the superficial femoral artery (SFA) or popliteal artery were prospectively enrolled in a DUS protocol (≤1 week after intervention, then at 3, 6, and 12 months thereafter). Peak systolic velocity (PSV) and velocity ratio (Vr) were used to categorize the treated artery: normal was PSV <200 cm/s and Vr <2, moderate stenosis was PSV = 200-300 cm/s or Vr = 2-3, and severe stenosis was PSV >300 cm/s or Vr >3. Reinterventions were generally performed for persistent or recurrent symptoms, allowing us to analyze the natural history of DU-detected lesions and to perform sensitivity and specificity analysis for DUS criteria predictive of failure.

Results: Ninety-four limbs (85 patients) underwent EVT for SFA-popliteal disease and were prospectively enrolled in a DUS protocol. The initial scans were normal in 61 limbs (65%), and serial DU results remained normal in 38 (62%). In 17 limbs (28%), progressive stenoses were detected during surveillance. The rate of thrombosis in this subgroup was 10%. Moderate stenoses were detected in 28 (30%) limbs at initial scans; of these, 39% resolved or stabilized, 47% progressed to severe, and occlusions developed in 14%. Five (5%) limbs harbored severe stenoses on initial scans, and 80% of lesions resolved or stabilized. Progression to occlusion occurred in one limb (20%). The last DUS showed 25 limbs harbored severe stenoses; of these, 13 (52%) were in symptomatic patients and thus required reintervention regardless of DU findings. Eleven limbs (11%) eventually occluded. Sensitivity and specificity of DUS to predict occlusion were 88% and 60%, respectively.

Conclusions: DUS does not reliably predict arterial occlusion after EVT. Stenosis after EVT appears to have a different natural history than restenosis after vein graft bypass. EVT patients are more likely to have severe stenosis when they present with recurrent symptoms, in contrast to vein graft patients, who commonly have occluded grafts when they present with recurrent symptoms. The potential impact of routine DU-directed reintervention in patients after EVT is questionable. The natural history of DU-detected stenosis after femoropopliteal endovascular therapy suggests questionable clinical utility of routine DUS.
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http://dx.doi.org/10.1016/j.jvs.2011.08.010DOI Listing
February 2012

Aortoiliac aneurysm repair in kidney transplant recipients.

Vasc Endovascular Surg 2009 Feb-Mar;43(1):30-45. Epub 2008 Nov 7.

Department of Vascular Surgery, Southern Arizona Veteran Affairs Health Care System (SAVAHCS), Tucson, Arizona 85723, USA.

A potential problem during endovascular aortic aneurysm repair (EVAR) or open repair in renal allograft patients is ischemia of the transplanted kidney. In this study, kidney transplant patients who underwent aortic aneurysm repair in our institution were added to similar cases extracted from the literature to represent the basis of this work. Comparisons between patients treated with open surgery versus EVAR were performed in terms of renal function. In the EVAR group, most aneurysms were infrarenal, and 84% were treated with modular bifurcated devices. Protective kidney allograft perfusion measures were not used. The pre- and postoperative Cr was 1.69 and 1.73 mg/dL, respectively (P = .412). All EVAR patients had good outcomes. Complications included 8 endoleaks and 1 limb ischemia case. Three patients died from aortic repair-unrelated reasons. In the open group, the pre-and postoperative Cr was 1.45 and 1.37 mg/dL, respectively (P = .055). Most cases were infrarenal and mostly treated by aortobiiliac bypasses. In 16%, no adjuvant allograft perfusion was provided. In the rest, temporary axillofemoral bypasses were used most often. Most outcomes were favorable (57%). Reported procedural-related complications included arterial embolism, wound infection, and pneumonia. Deaths were reported in 5 occasions (none allograft failure dependent). No differences in Cr between EVAR and open techniques (P = .13) were seen. Aneurysm repair in kidney transplant recipients is associated with excellent renal preservation. Adverse outcomes were all allograft failure independent in both groups. EVAR without special allograft protection measures seems to be equally effective as open surgery with or without adjuvant kidney transplant perfusion.
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http://dx.doi.org/10.1177/1538574408322654DOI Listing
April 2009

Aortic stent-graft explantation in a kidney transplant recipient.

Ann Vasc Surg 2009 Jul-Aug;23(4):535.e21-6. Epub 2008 Oct 14.

University of Arizona Health Science Center, Southern Arizona Veteran Affairs Health Care System, Vascular Surgery Section, Tucson, Arizona, USA.

AAA repair in renal transplant recipients has generated a variety of methods of managing the allograft. Endovascular techniques have been successfully employed in this patient population. Due to inherent limitations of present endovascular methods, occasional stent-graft excision must be performed. We present a case of aortic stent-graft excision in a renal transplant recipient using a pump-oxygenator to maintain allograft perfusion.
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http://dx.doi.org/10.1016/j.avsg.2008.08.017DOI Listing
August 2009

Functional MRI of the primary somatosensory cortex in extinction to simultaneous bilateral tactile stimuli due to right temporal lobe stroke.

Neurocase 2008 25;14(5):419-24. Epub 2008 Sep 25.

Department of Radiology, Thompson Center, University of Missouri, Columbia, MO 65211, USA.

Patients with right posterior temporoparietal cortical lesions often exhibit extinction to tactile double simultaneous stimuli (EDSS). It is not known whether sensory unawareness-extinction results from suppression of sensory input into the somatosensory cortex (SI), inhibition of SI, or interference which prevents SI output from activating and being fully processed by association areas. A patient with EDSS due to a right temporal stroke sparing SI and posterior parietal cortex and eight age-matched healthy controls were studied with fMRI during tactile stimulation. The volume of activation of SI during tactile stimulation of the right hand, the left hand and both hands was measured and the patient's volume of activation was compared to that of the control subjects in each of these stimulus conditions. Although the patient demonstrated behavioral EDSS, during fMRI the patient's activation of SI on both sides was within the range of the control participants' volumes of activation. These findings suggest that EDSS in patients with a right temporal lobe stroke results from processing abnormalities that occur after these afferent tactile stimuli are processed by SI.
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http://dx.doi.org/10.1080/13554790802422112DOI Listing
January 2009

Superficial femoral artery thrombosis as a cause for distal embolism in primary antiphospholipid syndrome.

J Vasc Surg 2008 Aug;48(2):472-7

University of Arizona Health Science Center and Southern Arizona Veterans Affairs Health Care System, Tucson, Ariz, USA.

Antiphospholipid syndrome is a diagnosis with the clinical manifestations of thromboses in the presence of an antiphospholipid antibody. A 25-year-old man with a history of deep venous thrombosis, pulmonary emboli, and myocardial infarction, and receiving long-term anticoagulation with warfarin, all due to primary antiphospholipid syndrome, presented with blue toe syndrome from a primary superficial femoral artery thrombus. He was anticoagulated with fondaparinux in addition to dipyridamole and aspirin perioperatively. The area of thrombus was resected and reconstructed using a cephalic vein interposition graft. This report reviews antiphospholipid syndrome and identifies potential questions and problems relating to a rare clinical presentation.
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http://dx.doi.org/10.1016/j.jvs.2008.02.052DOI Listing
August 2008

Measure what matters: institutional outcome data are superior to the use of surrogate markers to define "center of excellence" for abdominal aortic aneurysm repair.

Ann Vasc Surg 2008 May-Jun;22(3):328-34. Epub 2008 Apr 14.

Department of Surgery, University of Arizona Health Sciences Center, Tucson, AZ 85719, USA.

Outcome analysis is increasingly being used to develop health-care policy and direct patient referral. For example, the Leapfrog Group health-care quality initiative has proposed "evidence-based hospital" referral criteria for specific procedures including elective abdominal aortic aneurysm repair (AAA-R). These criteria include an annual hospital AAA operative volume exceeding 50 cases and provision of intensive care unit (ICU) care by board-certified intensivists. Outcomes after AAA-R are reportedly influenced by presentation (intact vs. ruptured), operative approach (endovascular vs. open, transperitoneal vs. retroperitoneal), surgeon subspecialty, case volume (hospital and surgeon), and provision of postoperative care by an intensivist. The purpose of this study was to compare our single-center results with those of high-volume centers to assess the validity of the concept that surrogate markers, such as case volume or intensivist involvement, can be used to estimate procedural outcome. A retrospective review was performed of AAA-Rs at one low-volume academic medical center from January 1994 to March 2005. Demographic data, aneurysm diameter and location, operative indications, and repair approach were documented. Postoperative complications, mortality rates, and hospital and ICU length of stay (LOS) were noted and compared to established benchmarks. During the study period, 270 patients underwent AAA-R (annual mean = 27 hospital cases and 13.4 cases/attending vascular surgeon). ICU care was provided by a dedicated vascular surgery service without routine intensivist involvement. Open, elective, infrarenal AAA-R was performed in 161 patients (60%), with a 2.5% hospital mortality rate (30-day, 3.1%). Thirty-three (12%) patients underwent elective endovascular aneurysm repair (EVAR), with no mortality. Both ICU (3.7 vs. 1.4 days, p = 0.03) and hospital (9.2 vs. 2.8 days, p = 0.002) LOS were significantly reduced after EVAR compared to open repair. Hospital LOS was significantly lower after open retroperitoneal repair compared to transperitoneal repair (6.1 vs. 10.3 days, p = 0.001). Thirty-five patients (13%) underwent ruptured AAA-R, with only 34.3% mortality (in-hospital and 30-day). Forty-one patients (15%) underwent repair of complex aortic aneurysms, with 14.1% mortality. There are increasing societal and economic pressures to direct patient referrals to "centers of excellence" for specific surgical procedures. Although our institution meets neither of the Leapfrog Group's proposed criteria, our mortality and LOS for both intact and ruptured infrarenal AAA-R are equivalent or superior to published benchmarks for high-volume hospitals. Individual institutional outcome results such as these suggest that patient referral and care should be based upon actual, carefully verified outcome data rather than utilization of surrogate markers such as case volume and subspecialist involvement in postoperative care.
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http://dx.doi.org/10.1016/j.avsg.2007.09.013DOI Listing
June 2008

Portomesenteric reconstruction during Whipple procedures: review and report of a case.

Vasc Endovascular Surg 2007 Dec-2008 Jan;41(6):537-46

Southern Arizona Veterans Affairs Health Care System, University of Arizona Health Science Center Tucson, Arizona 85723, USA.

A 60-year-old man undergoing a Whipple procedure to treat a pancreatic cancer was found to have tumor adherence to the portal vein. An en block pancreaticoduodenectomy with segmental portal vein resection (PVR) was performed. A primary portal vein anastomosis was initially attempted but failed. Hemodynamic deterioration led the authors to perform a temporary prosthetic portal vein interposition graft and abdominal closure. The following morning, once stable, the patient was brought back to the operating room for autologous reconstruction with femoral vein and completion of the pancreaticoduodenectomy. The role of PVR for vein invasion or tumor adherence during a Whipple procedure is still under debate. However, there is growing evidence that the perioperative morbidity and long-term survival in patients who undergo a pancreaticoduodenectomy with PVR are similar to those of patients without vein resection. Therefore a combined resection of the pancreatic head and the portal vein has been suggested in the absence of other contraindications for resection to be able to offer a curative surgical intervention to a larger number of patients. The authors herein report the details of a patient's case and also review the currently available methods for PVR and reconstruction.
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http://dx.doi.org/10.1177/1538574407305019DOI Listing
February 2008

Probable zoonotic aortitis due to group C streptococcal infection.

J Vasc Surg 2007 Nov;46(5):1039-43

Vascular Surgery Section, the University of Arizona Health Science Center and the Southern Arizona Veteran Affairs Health Care System, Tucson, AZ 85723, USA.

Human infections due to group C streptococcus (SGC) are unusual. Among them, vascular compromise, especially aortic involvement, is extremely rare. A case of microbial aortitis with aneurysm formation, likely secondary to a SGC soft tissue infection, in a 61-year-old patient who was caring for a purulent leg wound of his horse, is presented. He was successfully treated with antibiotics and in situ aortic replacement with a prosthetic graft and an omental wrap. He remains well almost 2 years after surgical intervention. Aortic infection caused by SGC is a rare condition that can be successfully treated with in situ prosthetic graft replacement.
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http://dx.doi.org/10.1016/j.jvs.2007.05.051DOI Listing
November 2007

Network model of decreased context utilization in autism spectrum disorder.

J Autism Dev Disord 2007 Jul;37(6):1040-8

Department of Neurology, The Ohio State University Medical Center, Means Hall 469, 1654 Upham Drive, Columbus, OH 43210, USA.

Individuals with autism spectrum disorders (ASD) demonstrate impaired utilization of context, which allows for superior performance on the "false memory" task. We report the application of a simplified parallel distributed processing model of context utilization to the false memory task. For individuals without ASD, experiments support a model wherein presentation of one word, e.g., ''apple,'' strongly activates the neighboring nodes of closely related words such as ''fruit,'' ''tree,'' whereas in ASD these neighboring nodes are relatively less activated. We demonstrate this model to be consistent with the superior performance on recognition testing on the false memory test, but not on free recall. This may have an anatomic basis in diminished hippocampal neuronal arborization and the abnormal minicolumnar pathology in ASD.
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http://dx.doi.org/10.1007/s10803-006-0242-7DOI Listing
July 2007

A neural systems-based neurobiology and neuropsychiatry course: integrating biology, psychodynamics, and psychology in the psychiatric curriculum.

Acad Psychiatry 2006 Sep-Oct;30(5):410-5

Department of Psychiatry, Malcolm Grow Medical Center, Andrews Air Force Base, MD 20762, USA.

Objective: Psychotherapy and biological psychiatry remain divided in psychiatry residency curricula. Behavioral neurobiology and neuropsychiatry provide a systems-level framework that allows teachers to integrate biology, psychodynamics, and psychology.

Method: The authors detail the underlying assumptions and outline of a neural systems-based neuroscience course they teach at the National Capital Consortium Psychiatry Residency Program. They review course assessment reports and classroom observations.

Results: Self-report measures and teacher observations are encouraging. By the end of the course, residents are able to discuss both neurobiological and psychodynamic/psychological concepts of distributed biological neural networks. They verbalize an understanding that psychology is biology, that any distinction is artificial, and that both are valuable.

Conclusions: A neuroscience curriculum founded on the underlying principles of behavioral neurobiology and neuropsychiatry is inherently anti-reductionistic and facilitates the acquisition of detailed information as well as critical thinking and cross-disciplinary correlations with psychological theories and psychotherapy.
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http://dx.doi.org/10.1176/appi.ap.30.5.410DOI Listing
January 2007

A systems approach to behavioral neurobiology: integrating psychodynamics and neuroscience in a psychiatric curriculum.

J Am Acad Psychoanal Dyn Psychiatry 2006 ;34(1):43-74

Office of the Air Force Surgeon General, Directorate of Modernization.

In the practice of medicine, an understanding of the biological functioning of organs and organ systems is the basis for theories of pathology and clinical practice. If psychoanalysis is to be accepted by the medical and psychiatric community, it must be based on a sophisticated understanding of the organ from which mental and emotional experiences emanate and use scientifically acceptable language. Each approach to psychotherapy has its own vocabulary for describing neuropsychological processes. Neurobiological vocabulary provides the various factions "neutral ground" upon which to carry on a multidisciplinary integrative dialogue. An understanding of behavioral neuroscience allows the therapist to look beyond the labels that spawn division and identify unifying biological principles that are described in a variety of ways in a multitude of theories. We contend that the neural network/representational approach to neurobiology views human mental experience as the result of multiple complex integrated systems, and is therefore holistic and antireductionistic in its perspective. Such a biologically informed psychotherapy facilitates integration of skill sets and flexibility in technique. With these principles in mind, the therapist can base his or her approach to the patient based on these principles rather than on devotion to one particular "school" or another. Because behavioral neuroscience supports many of the basic tenets of psychoanalytic theory, such an integrative psychotherapy would be psychodynamically informed. In this paper, we outline some of the ideas we present in our neuroscience course and how we relate biological concepts with some core principles of psychodynamics and psychotherapy.
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http://dx.doi.org/10.1521/jaap.2006.34.1.43DOI Listing
September 2006

The limitations of magnetic resonance angiography in the diagnosis of renal artery stenosis: comparative analysis with conventional arteriography.

J Vasc Surg 2005 Mar;41(3):462-8

Division of Vascular Surgery, University of Arizona Health Science Center, Tucson, AZ 85724, USA.

Purpose: Gadolinium-enhanced magnetic resonance angiography (MRA) is commonly used as a screening modality for the detection of renal artery stenosis. However, evidence supporting its utility in clinical practice is lacking; few rigorous studies have compared MRA with contrast arteriography (CA). After making anecdotal clinical observations that MRA sometimes overestimated the degree of renal artery stenosis, we decided to determine the interobserver variability, sensitivity, specificity, and diagnostic accuracy of MRA compared with CA.

Methods: From September 1999 to April 2003, we evaluated 68 renal arteries in 34 patients with clinically suspected renal artery stenosis using both MRA and CA. All studies were independently reviewed by four blinded observers. Renal arteries were categorized by MRA as normal, <50%, and >50% stenosis/occlusion. The sensitivity, specificity, and accuracy of MRA detection of renal artery stenosis were compared to CA as the gold standard. Interobserver variability (kappa) was also calculated.

Results: MRA demonstrated 87% sensitivity, 69% specificity, 85% accuracy, 95% negative predictive value, and 51% positive predictive value for the diagnosis of renal artery stenosis. Interobserver agreement was moderate for MRA (kappa = 0.53) and good for CA (kappa = 0.76). In 21 arteries (31%), MRA was falsely positive.

Conclusions: In patients with a high clinical suspicion of renal artery stenosis, MRA is 87% sensitive in the detection of >50% stenosis. However, MRA is relatively nonspecific compared with CA and results in significant overestimation of renal artery stenosis in nearly one third of patients. To reduce unnecessary CA, clinicians should consider supplemental studies.
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http://dx.doi.org/10.1016/j.jvs.2004.12.045DOI Listing
March 2005

Effect of anxiolytics on cognitive flexibility in problem solving.

Cogn Behav Neurol 2004 Jun;17(2):93-7

Ohio State University, Columbus, Ohio, USA.

Objective: Our purpose is to examine the effect of different classes of anxiolytics on cognitive flexibility.

Background: Situational stressors and anxiety impede performance on "creativity" tests requiring cognitive flexibility. Noradrenergic agents have been shown to modulate cognitive flexibility as assessed by performance on anagrams. To determine whether these findings on noradrenergic modulation of cognitive flexibility are specific to the noradrenergic system or are a nonspecific anxiety effect, we compared the effects of propranolol, lorazepam, and placebo on the anagram task.

Methods: Subjects attended 3 test sessions. Prior to each session, subjects were given 1 of the 3 drugs. As in previous research, the natural log of the solution latency of each test item was summed for each test session and compared across drug conditions.

Results: For subjects able to solve the anagrams, solution times after propranolol, but not lorazepam, were significantly lower than after placebo.

Conclusions: Therefore, this suggests that the phenomenon of noradrenergic modulation of cognitive flexibility does not result from a nonspecific anxiolytic effect, but rather is specific to the noradrenergic system.
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http://dx.doi.org/10.1097/01.wnn.0000119240.65522.d9DOI Listing
June 2004

Hyponatremic hypertensive syndrome (HHS) in an 18-month old-child presenting as malignant hypertension: a case report.

BMC Nephrol 2004 Apr 27;5. Epub 2004 Apr 27.

Steele Memorial Children's Research Center, Department of Pediatrics, University of Arizona, Tucson, USA.

Background: The combination of hyponatremia and renovascular hypertension is called hyponatremic hypertensive syndrome (HHS). Malignant hypertension as a presentation has been reported in adults with HHS but is rare in children.

Case Presentation: An eighteen month-old male presented with drowsiness, sudden onset status epilepticus and blood pressure of 210/160. The electrolytes on admission revealed sodium of 120 mEq/L and potassium of 2.1 mEq/L. The peripheral renin activity (PRA) was 172 ng/ml/min (normal 3-11 ng/ml/min) and serum aldosterone level was 91 ng/dl (normal 4 to 16 ng/dl). Patient underwent angioplasty with no success, followed by surgical correction. Two years since the diagnosis, the blood pressure is controlled with labetolol and amlodipine (at less than sixth of the pre-operative dosages). The PRA is 2.4 ng/ml/min and aldosterone 15.5 ng/dl. The child not only had three renal arteries on left but all of them were stenosed which to best of our knowledge has not been described.

Conclusion: As uncommon as HHS with malignant hypertension may be in adults it is under-reported in children and purpose of the case report is to raise its awareness.
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http://dx.doi.org/10.1186/1471-2369-5-5DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC420241PMC
April 2004

A new look at outcomes after infrainguinal bypass surgery: traditional reporting standards systematically underestimate the expenditure of effort required to attain limb salvage.

J Vasc Surg 2004 Feb;39(2):330-5

Vascular Surgery Section, University of Arizona Health Sciences Center, Tucson, AZ 70121, USA.

Background: Graft patency, limb salvage, and mortality are the traditional means of assessing the outcome of infrainguinal bypass surgery (IBS). However, these measures underestimate patient morbidity and fail to consider the entire spectrum of treatment required to restore the patients to their premorbid state. The aim of this study was to quantify the efforts required to achieve limb salvage by assessing three nontraditional outcomes: (1). index limb reoperation rate in 3 months, (2). hospital readmission rate in the first 6 months after IBS, and (3). wound-healing time.

Methods: We retrospectively analyzed 318 IBSs performed at a single institution. Repeat operations for limb or graft-related problems and readmissions within 6 months of the initial operation were recorded. When available, wound-healing time was determined. Pertinent demographics and comorbidities were subjected to univariate and multivariate analysis to determine risk factors for adverse outcomes.

Results: Seventy-two percent of patients underwent IBS for critical limb ischemia (CLI), and 84% had below-knee popliteal or distal bypasses. Among those who underwent IBS for CLI, 48.9% of patients required at least one reoperation within 3 months. Within 6 months, 49.3% of patients required hospital readmission. Time to heal exceeded 3 months in 54% of patients. After multivariate analysis, tissue loss and minority status were significant risk factors for reoperation within 3 months. Tissue loss and renal failure increased the odds for readmission within 6 months. Diabetes was the sole risk factor for prolonged wound healing.

Conclusions: IBS for limb salvage is often complicated by prolonged recovery and multiple reoperations and readmissions. Traditional reporting standards for limb salvage operations need modification to reflect the true outcome of such procedures.
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http://dx.doi.org/10.1016/j.jvs.2003.10.020DOI Listing
February 2004

What you get out of memory depends on the question you ask.

J Exp Psychol Learn Mem Cogn 2003 Sep;29(5):797-812

The Key Centre for Human Factors and Applied Cognitive Psychology, University of Queensland, Brisbane, Queensland 4072, Australia.

Following study, participants received 2 tests. The 1st was a recognition test; the 2nd was designed to tap recollection. The objective was to examine performance on Test 1 conditional on Test 2 performance. In Experiment 1, contrary to process dissociation assumptions, exclusion errors better predicted subsequent recollection than did inclusion errors. In Experiments 2 and 3, with alternate questions posed on Test 2, words having high estimates of recollection with one question had high estimates of familiarity with the other question. Results supported the following: (a) the 2-test procedure has considerable potential for elucidating the relationship between recollection and familiarity; (b) there is substantial evidence for dependency between such processes when estimates are obtained using the process dissociation and remember-know procedures; and (c) order of information access appears to depend on the question posed to the memory system.
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http://dx.doi.org/10.1037/0278-7393.29.5.797DOI Listing
September 2003

Is early postoperative duplex scan surveillance of leg bypass grafts clinically important?

J Vasc Surg 2003 Mar;37(3):495-500

Division of Vascular Surgery, University of Arizona Health Sciences Center, 1501 N. Campbell Avenue, Tucson, AZ 85724, USA.

Purpose: The typical leg bypass surveillance program begins with a duplex scan evaluation of the vein graft 3 months after surgery; studies are repeated every 3 months during the first year of follow-up and are fully reimbursed by our Medicare carrier. Some authors have recommended early (before discharge or first postoperative visit) duplex scanning to identify high-risk grafts. However, the natural history of velocity disturbances detected with early scans is unclear, and furthermore, such studies are not reimbursed by Medicare.

Methods: We reviewed all infrainguinal vein bypass grafts prospectively entered into a surveillance protocol that included an early (<6 weeks) duplex scan study. Routine completion angiography was performed at the initial operation in all patients. Early duplex scan results, the need for graft revision, and detailed follow-up of these bypass grafts were analyzed.

Results: Early duplex scans were performed in 224 bypass grafts placed in 204 patients. Early scans were abnormal (peak systolic velocity [PSV], >200 cm/s) in 58 grafts (26%). Six grafts of the 58 (10.3%; 2.7%) with an early abnormal duplex scan and unrepaired defects occluded during the follow-up period. Thirty grafts were revised on the basis of the initial early scan; 23 of these revisions were performed for critical or rapidly progressive lesions in the first 3 postoperative months. Seven lesions progressed more slowly and were repaired at a mean of 8 months after surgery. Interestingly, 22 flow abnormalities (37%) resolved or stabilized despite a PSV of more than 300 cm/s in six cases (27%). Clear duplex scan evidence of regression or progression of these early flow abnormalities occurred within 3 months in 51/58 cases (88%). A total of 68 grafts (30%) were revised during the entire study period; 30 of these (44%) were on the basis of the early abnormal scan.

Conclusion: Despite normal completion arteriography, early graft velocity abnormalities are strikingly common and were detected in 26% of the 224 infrainguinal vein grafts in this series. These lesions were clinically important because 52% necessitated revision. Surprisingly, however, 38% of these early flow disturbances resolved, despite a PSV of more than 300 cm/s in 27% of cases. Early duplex scan surveillance singularly detects a clinically significant subgroup of grafts that need revision. The possible origin of these early lesions deserves further inquiry, but on the basis of its clinical yield, we recommend that early duplex scan surveillance of infrainguinal bypass grafts should be routine and should be considered for Medicare reimbursement.
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http://dx.doi.org/10.1067/mva.2003.115DOI Listing
March 2003

Central beta-adrenergic modulation of cognitive flexibility.

Neuroreport 2002 Dec;13(18):2505-7

Department of Psychiatry, University of Colorado Health Science Center, Denver, CO 80262, USA.

Situational stressors and anxiety impede performance on creativity tests requiring cognitive flexibility. Preliminary research revealed better performance on a task requiring cognitive flexibility, the anagram task, after propranolol (beta-adrenergic antagonist) than after ephedrine (beta-adrenergic agonist). However, propranolol and ephedrine have both peripheral and central beta-adrenergic effects. In order to determine whether noradrenergic modulation of cognitive flexibility is a centrally or peripherally mediated phenomenon, we compared the effects of propranolol (peripheral and central beta-blocker), nadolol (peripheral beta-blocker), and placebo on anagram task performance. Solution latency scores for each subject were compared across the drug conditions. Anagram solution latency scores after propranolol were significantly lower than after nadolol. This suggests a centrally mediated modulatory influence of the noradrenergic system on cognitive flexibility.
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http://dx.doi.org/10.1097/00001756-200212200-00025DOI Listing
December 2002

Distal revascularization-interval ligation: a durable and effective treatment for ischemic steal syndrome after hemodialysis access.

J Vasc Surg 2002 Aug;36(2):250-5; discussion 256

Section of Vascular Surgery, The University of Arizona Health Sciences Center, Tucson, AZ 85724, USA.

Purpose: The treatment of hemodialysis access-induced ischemic steal syndrome is challenging. Despite promising early results with the distal revascularization-interval ligation (DRIL) procedure, the operation has not been widely adopted because of concerns about its complexity and long-term efficacy. The purpose of this report was to determine the efficacy and durability of the DRIL procedure in relieving hand ischemia and in maintaining access patency in the setting of hemodialysis access-induced ischemia.

Methods: A retrospective review was performed of all patients who underwent the DRIL procedure for access-induced ischemia. Demographic information was compiled, as were data regarding access and bypass patency, limb salvage, and patient survival. Arteriovenous access and brachial artery bypass patency rates were determined with life-table methods.

Results: Between 1995 and 2001, we performed 55 DRIL procedures in 52 patients (35 women and 17 men; mean age, 60.8 years; range, 30 to 86 years). The indications for surgery were ischemic pain in 27 patients, tissue loss in 20 patients, loss of neurologic function in four patients, and pain on hemodialysis in one patient. Most patients (92%) had diabetes. The mean interval from access placement to DRIL was 7.4 months (range, 1 to 84 months). The mean follow-up interval was 16 months (range, 1 to 67 months). The brachial artery bypass primary patency rate was 80% at 4 years, and the arteriovenous access primary patency rate was 83% at 1 year. Forty-seven of 52 patients (90%) had substantial or complete relief of ischemic hand symptoms, and 15 of 20 patients with digital ischemic lesions have healed completely.

Conclusion: DRIL is a durable and effective procedure that reliably accomplishes the twin goals in the treatment of angioaccess-induced ischemia: persistent relief of hand ischemia and continued access patency.
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http://dx.doi.org/10.1067/mva.2002.125025DOI Listing
August 2002
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