Publications by authors named "Nancy J Fischbein"

76 Publications

Microsurgical Resection of an Orbital Arteriovenous Malformation With Intraoperative Digital Subtraction Angiography.

Ophthalmic Plast Reconstr Surg 2020 Sep 22. Epub 2020 Sep 22.

Department of Ophthalmology, Byers Eye Institute, Stanford University School of Medicine.

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http://dx.doi.org/10.1097/IOP.0000000000001815DOI Listing
September 2020

Radiographic surveillance of abdominal free fat graft in complex parotid pleomorphic adenomas: A case series.

Heliyon 2020 May 4;6(5):e03894. Epub 2020 May 4.

Department of Otolaryngology - Head and Neck Surgery, Stanford University School of Medicine, Stanford, CA, USA.

Background: Free abdominal fat transfer is commonly used to restore facial volume and improve cosmesis after parotidectomy for pleomorphic adenomas. We describe the radiographic characteristics of these grafts on follow-up imaging.

Methods: Medical records of four patients who underwent parotidectomy with abdominal fat graft in 2016 and had follow up imaging available were retrospectively analyzed. An otolaryngologist and neuroradiologist reviewed imaging studies, evaluated the fat grafts, and monitored for residual or recurrent disease.

Results: The abdominal fat was successfully grafted in all four patients. Post-operative baseline magnetic resonance imaging and additional surveillance imaging showed fat grafts with minimal volume loss. However, there was development of irregular enhancement consistent with fat necrosis in two of the four patients.

Conclusions: Radiographic surveillance of free fat graft reconstruction after pleomorphic adenoma resection shows minimal contraction in size but development of fat necrosis. Recognition of expected changes should help avoid confusion with residual or recurrent disease, reassuring both patient and treating physician.
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http://dx.doi.org/10.1016/j.heliyon.2020.e03894DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7210407PMC
May 2020

Risks of Neoplasia and Malignancy in Surgically Resected Cystic Parotid Lesions.

Otolaryngol Head Neck Surg 2020 01 3;162(1):79-86. Epub 2019 Dec 3.

Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, California, USA.

Objectives: To evaluate the risks of neoplasm and malignancy in surgically treated cystic parotid masses compared with solid or mixed lesions and to evaluate the performance of fine-needle aspiration (FNA) in parotid cysts.

Study Design: Retrospective cross-sectional study.

Setting: Single-institution academic tertiary care center.

Subjects And Methods: Patients without a history of human immunodeficiency virus or head and neck cancer who underwent parotidectomy for parotid masses and had preoperative imaging to characterize lesions as cystic, solid, or mixed (ie, partially cystic and partially solid). We assessed the risks of neoplasia and malignancy, adjusting for age, sex, race/ethnicity, facial nerve weakness, and history of malignancy. We also evaluated the sensitivity and specificity of FNA.

Results: We included 308 patients, 27 of whom had cystic parotid masses (5 simple and 22 complex). Cystic masses were less likely to be neoplastic compared to solid or mixed masses (44% vs 97%; odds ratio [OR], 0.03; 95% confidence interval [CI], 0.01-0.07); however, there was no difference in the risk of malignancy (22% vs 26%; OR, 0.81; 95% CI, 0.32-2.10). Cystic masses were more likely to yield nondiagnostic FNA cytology results, but for diagnostic samples, FNA was 86% sensitive and 33% specific for diagnosing neoplasia and 75% sensitive and 83% specific for diagnosing malignancy.

Conclusion: In our population, cystic masses undergoing surgery were less likely to be neoplastic but had a similar risk of malignancy as solid masses. The risk of malignancy should be considered in the management of cystic parotid masses.
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http://dx.doi.org/10.1177/0194599819889699DOI Listing
January 2020

Automated Detection of Intracranial Large Vessel Occlusions on Computed Tomography Angiography: A Single Center Experience.

Stroke 2019 10 9;50(10):2790-2798. Epub 2019 Sep 9.

Department of Radiology, University of Melbourne, Parkville, Australia (R.B.).

Background and Purpose- Endovascular thrombectomy is highly effective in acute ischemic stroke patients with an anterior circulation large vessel occlusion (LVO), decreasing morbidity and mortality. Accurate and prompt identification of LVOs is imperative because these patients have large volumes of tissue that are at risk of infarction without timely reperfusion, and the treatment window is limited to 24 hours. We assessed the accuracy and speed of a commercially available fully automated LVO-detection tool in a cohort of patients presenting to a regional hospital with suspected stroke. Methods- Consecutive patients who underwent multimodal computed tomography with thin-slice computed tomography angiography between January 1, 2017 and December 31, 2018 for suspected acute ischemic stroke within 24 hours of onset were retrospectively identified. The multimodal computed tomographies were assessed by 2 neuroradiologists in consensus for the presence of an intracranial anterior circulation LVO or M2-segment middle cerebral artery occlusion (the reference standard). The patients' computed tomography angiographies were then processed using an automated LVO-detection algorithm (RAPID CTA). Receiver-operating characteristic analysis was used to determine sensitivity, specificity, and negative predictive value of the algorithm for detection of (1) an LVO and (2) either an LVO or M2-segment middle cerebral artery occlusion. Results- CTAs from 477 patients were analyzed (271 men and 206 women; median age, 71; IQR, 60-80). Median processing time was 158 seconds (IQR, 150-167 seconds). Seventy-eight patients had an anterior circulation LVO, and 28 had an isolated M2-segment middle cerebral artery occlusion. The sensitivity, negative predictive value, and specificity were 0.94, 0.98, and 0.76, respectively for detection of an intracranial LVO and 0.92, 0.97, and 0.81, respectively for detection of either an intracranial LVO or M2-segment middle cerebral artery occlusion. Conclusions- The fully automated algorithm had very high sensitivity and negative predictive value for LVO detection with fast processing times, suggesting that it can be used in the emergent setting as a screening tool to alert radiologists and expedite formal diagnosis.
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http://dx.doi.org/10.1161/STROKEAHA.119.026259DOI Listing
October 2019

Comparison of T2*GRE and DSC-PWI for hemorrhage detection in acute ischemic stroke patients: Pooled analysis of the EPITHET, DEFUSE 2, and SENSE 3 stroke studies.

Int J Stroke 2020 02 10;15(2):216-225. Epub 2019 Jul 10.

Department of Radiology, Stanford University, Stanford, CA, USA.

Aims: The objective of this study was to compare the diagnostic performance of the baseline pre-contrast images of dynamic susceptibility contrast perfusion-weighted imaging (DSC-PWI) with conventional T2*gradient recalled echo (GRE) imaging for detection of hemorrhage in acute ischemic stroke patients.

Material And Methods: T2*GRE and DSC-PWI from 393 magnetic resonance imaging scans from 221 patients enrolled in three prospective stroke studies were independently evaluated by two readers blinded to clinical and other imaging data. Agreement between T2*GRE and DSC-PWI for the presence of hemorrhage, and acute hemorrhagic transformation, was assessed using the kappa statistic. Inter-reader agreement was also assessed using the kappa statistic.

Results: Agreement between the baseline images of DSC-PWI and T2*GRE regarding the presence of hemorrhage was almost perfect (k : 0.90, 95% confidence interval 0.86-0.95 and k : 0.91, 95% confidence interval 0.87-0.96). Agreement between the sequences was still higher for detection of acute hemorrhagic transformation (k : 0.94, 95% confidence interval 0.91-0.98 and k : 0.95, 95% confidence interval 0.92-0.98). Inter-reader agreement for detection of hemorrhage was also almost perfect for both T2*GRE (k: 0.95, 95% confidence interval 0.91-0.98) and DSC-PWI (k: 0.96, 95% confidence interval 0.93-0.99). Acute hemorrhagic transformation detected on T2*GRE was missed on DSC-PWI by one or both readers in 5/393 (1.3%) scans.

Conclusion: The almost perfect statistical agreement between DSC-PWI and conventional T2*GRE suggests that DSC-PWI is sufficient for hemorrhage screening prior to thrombolysis in stroke patients. T2*GRE can therefore be omitted when DSC-PWI is included, thereby shortening the acute ischemic stroke magnetic resonance imaging protocol and expediting treatment. ClinicalTrials.gov Identifier: NCT02586415.
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http://dx.doi.org/10.1177/1747493019858781DOI Listing
February 2020

Neuroimaging selection for thrombectomy in pediatric stroke: a single-center experience.

J Neurointerv Surg 2019 Sep 16;11(9):940-946. Epub 2019 May 16.

Department of Radiology, Division of Neuroimaging & Neurointervention, Stanford University School of Medicine, Stanford, CA, USA.

Background: The extended time window for endovascular therapy in adult stroke represents an opportunity for stroke treatment in children for whom diagnosis may be delayed. However, selection criteria for pediatric thrombectomy has not been defined.

Methods: We performed a retrospective cohort study of patients aged <18 years presenting within 24 hours of acute large vessel occlusion. Patient consent was waived by our institutional IRB. Patient data derived from our institutional stroke database was compared between patients with good and poor outcome using Fisher's exact test, t-test, or Mann-Whitney U-test.

Results: Twelve children were included: 8/12 (66.7%) were female, mean age 9.7±5.0 years, median National Institutes of Health Stroke Scale (NIHSS) 11.5 (IQR 10-14). Stroke etiology was cardioembolic in 75%, dissection in 16.7%, and cryptogenic in 8.3%. For 2/5 with perfusion imaging, Tmax >4 s appeared to better correlate with NIHSS. Nine patients (75%) were treated: seven underwent thrombectomy alone; one received IV alteplase and thrombectomy, and one received IV alteplase alone. Favorable outcome was achieved in 78% of treated patients versus 0% of untreated patients (P=0.018). All untreated patients had poor outcome, with death (n=2) or severe disability (n=1) at follow-up. Among treated patients, older children (12.8±2.9 vs 4.2±5.0 years, P=0.014) and children presenting as outpatient (100% vs 0%, P=0.028) appeared to have better outcomes.

Conclusions: Perfusion imaging is feasible in pediatric stroke and may help identify salvageable tissue in extended time windows, though penumbral thresholds may differ from adult values. Further studies are needed to define criteria for thrombectomy in this unique population.
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http://dx.doi.org/10.1136/neurintsurg-2019-014862DOI Listing
September 2019

Arterial-spin labeling MRI identifies residual cerebral arteriovenous malformation following stereotactic radiosurgery treatment.

J Neuroradiol 2020 Feb 15;47(1):13-19. Epub 2019 Jan 15.

Department of Radiology, Neuroimaging and Neurointervention Division, Stanford University Hospital, 300, Pasteur Drive, Stanford, CA 94305, US.

Background And Purpose: Brain arteriovenous malformation (AVM) treatment by stereotactic radiosurgery (SRS) is effective, but AVM obliteration following SRS may take two years or longer. MRI with arterial-spin labeling (ASL) may detect brain AVMs with high sensitivity. We determined whether brain MRI with ASL may accurately detect residual AVM following SRS treatment.

Materials And Methods: We performed a retrospective cohort study of patients who underwent brain AVM evaluation by DSA between June 2010 and June 2015. Inclusion criteria were: (1) AVM treatment by SRS, (2) follow-up MRI with ASL at least 30 months after SRS, (3) DSA within 3 months of the follow-up MRI with ASL, and (4) no intervening AVM treatment between the MRI and DSA. Four neuroradiologists blindly and independently reviewed follow-up MRIs. Primary outcome measure was residual AVM indicated by abnormal venous ASL signal.

Results: 15 patients (12 females, mean age 29 years) met inclusion criteria. There were three posterior fossa AVMs and 12 supratentorial AVMs. Spetzler-Martin (SM) Grades were: SM1 (8%), SM2 (33%), SM3 (17%), SM4 (25%), and SM5 (17%). DSA demonstrated residual AVM in 10 patients. The pooled sensitivity, specificity, positive predictive value, and negative predictive value of venous ASL signal for predicting residual AVM were 100% (95% CI: 0.9-1.0), 95% (95% CI: 0.7-1.0), 98% (95% CI: 0.9-1.0), and 100% (95% CI: 0.8-1.0), respectively. High inter-reader agreement as found by Fleiss' Kappa analysis (k = 0.92; 95% CI: 0.8-1.0; P < 0.0001).

Conclusions: ASL is highly sensitive and specific in the detection of residual cerebral AVM following SRS treatment.
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http://dx.doi.org/10.1016/j.neurad.2018.12.004DOI Listing
February 2020

Intracranial Hemorrhage Imaging.

Semin Ultrasound CT MR 2018 Oct 27;39(5):441-456. Epub 2018 Feb 27.

Department of Radiology, Stanford University School of Medicine, Stanford, CA.

Intracranial hemorrhage is a medical event frequently encountered in the clinical practice of radiology that has significant potential for patient morbidity and mortality. The expedient and accurate identification of intracranial hemorrhage as well as elucidation of the underlying cause can assist in optimizing the care of these patients. In this review, we attempt to familiarize the reader with the imaging appearance of multiple types of intracranial hemorrhage, both intra-axial and extra-axial and utilizing both computed tomography and magnetic resonance imaging, as well as to provide a framework for assessment of the underlying cause of the hemorrhage.
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http://dx.doi.org/10.1053/j.sult.2018.01.003DOI Listing
October 2018

Practical Pearl: Use of MRI to Differentiate Pseudo-subarachnoid Hemorrhage from True Subarachnoid Hemorrhage.

Neurocrit Care 2018 08;29(1):113-118

Department of Neurosurgery, Stanford University School of Medicine, Stanford University Medical Center, 300 Pasteur Dr. MC5327, Stanford, CA, 94303, USA.

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http://dx.doi.org/10.1007/s12028-018-0547-3DOI Listing
August 2018

Clinical and Arterial Spin Labeling Brain MRI Features of Transitional Venous Anomalies.

J Neuroimaging 2018 05 4;28(3):289-300. Epub 2017 Dec 4.

Department of Radiology, Neuroimaging and Neurointervention, Stanford University Medical Center, Stanford, CA.

Background And Purpose: Transitional venous anomalies (TVAs) are rare cerebrovascular lesions that resemble developmental venous anomalies (DVAs), but demonstrate early arteriovenous shunting on digital subtraction angiography (DSA) without the parenchymal nidus of arteriovenous malformations (AVMs). We investigate whether arterial spin labeling (ASL) magnetic resonance imaging (MRI) can distinguish brain TVAs from DVAs and guide their clinical management.

Methods: We conducted a single-center retrospective review of patients with brain parenchymal DVA-like lesions with increased ASL signal on MRI. Clinical histories and follow-up information were obtained. Two readers assessed ASL signal location relative to the vascular lesion on MRI and, if available, the presence of arteriovenous shunting on DSA.

Results: Thirty patients with DVA-like lesions with increased ASL signal were identified. Clinical symptoms prompted MRI evaluation in 83%. Symptoms did not localize to the venous anomaly in 90%. Ten percent presented with acute symptoms, only one of whom presented with hemorrhage. ASL signal in relation to the venous anomaly was identified in: 50% in the adjacent parenchyma, 33% in the lesion, 7% in a distal draining vein/sinus, and 10% in at least two of these sites. Follow-up DSA confirmed arteriovenous shunting in 71% of ASL-positive venous anomalies. Interrater agreement was very good (κ = .81-1.0, P < .001).

Conclusion: A DVA-like lesion with increased ASL signal likely represents a TVA with arteriovenous shunting. Our study indicates that these lesions are usually incidentally detected and have a lower risk of hemorrhage than AVMs. ASL-MRI may be a useful tool to identify TVAs and guide further management of patients with TVAs.
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http://dx.doi.org/10.1111/jon.12487DOI Listing
May 2018

Fusion of Computed Tomography and PROPELLER Diffusion-Weighted Magnetic Resonance Imaging for the Detection and Localization of Middle Ear Cholesteatoma.

JAMA Otolaryngol Head Neck Surg 2016 10;142(10):947-953

Department of Otolaryngology-Head and Neck Surgery, Stanford University, Stanford, California.

Importance: A method to optimize imaging of cholesteatoma by combining the strengths of available modalities will improve diagnostic accuracy and help to target treatment.

Objective: To assess whether fusing Periodically Rotated Overlapping Parallel Lines With Enhanced Reconstruction (PROPELLER) diffusion-weighted magnetic resonance imaging (DW-MRI) with corresponding temporal bone computed tomography (CT) images could increase cholesteatoma diagnostic and localization accuracy across 6 distinct anatomical regions of the temporal bone.

Design, Setting, And Participants: Case series and preliminary technology evaluation of adults with preoperative temporal bone CT and PROPELLER DW-MRI scans who underwent surgery for clinically suggested cholesteatoma at a tertiary academic hospital. When cholesteatoma was encountered surgically, the precise location was recorded in a diagram of the middle ear and mastoid. For each patient, the 3 image data sets (CT, PROPELLER DW-MRI, and CT-MRI fusion) were reviewed in random order for the presence or absence of cholesteatoma by an investigator blinded to operative findings.

Main Outcomes And Measures: If cholesteatoma was deemed present on review of each imaging modality, the location of the lesion was mapped presumptively. Image analysis was then compared with surgical findings.

Results: Twelve adults (5 women and 7 men; median [range] age, 45.5 [19-77] years) were included. The use of CT-MRI fusion had greater diagnostic sensitivity (0.88 vs 0.75), positive predictive value (0.88 vs 0.86), and negative predictive value (0.75 vs 0.60) than PROPELLER DW-MRI alone. Image fusion also showed increased overall localization accuracy when stratified across 6 distinct anatomical regions of the temporal bone (localization sensitivity and specificity, 0.76 and 0.98 for CT-MRI fusion vs 0.58 and 0.98 for PROPELLER DW-MRI). For PROPELLER DW-MRI, there were 15 true-positive, 45 true-negative, 1 false-positive, and 11 false-negative results; overall accuracy was 0.83. For CT-MRI fusion, there were 20 true-positive, 45 true-negative, 1 false-positive, and 6 false-negative results; overall accuracy was 0.90.

Conclusions And Relevance: The poor anatomical spatial resolution of DW-MRI makes precise localization of cholesteatoma within the middle ear and mastoid a diagnostic challenge. This study suggests that the bony anatomic detail obtained via CT coupled with the excellent sensitivity and specificity of PROPELLER DW-MRI for cholesteatoma can improve both preoperative identification and localization of disease over DW-MRI alone.
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http://dx.doi.org/10.1001/jamaoto.2016.1663DOI Listing
October 2016

Design and rationale of a prospective, multi-institutional registry for patients with sinonasal malignancy.

Laryngoscope 2016 09 10;126(9):1977-80. Epub 2016 Jun 10.

Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Stanford, California, U.S.A.

Objectives/hypothesis: Assessment of patients with sinonasal malignancy is challenging due to the low disease incidence and diverse histopathology. The current literature is composed mainly of retrospective studies with heterogeneous cohorts, and the rarity of cases limits our understanding of disease characteristics and treatment outcomes. We describe the development of a prospective, multi-institutional registry that utilizes cloud-based computing to evaluate treatment outcomes in patients with sinonasal cancer.

Methods: A web-based, secure database was built to prospectively capture longitudinal outcomes and quality-of-life (QoL) data in patients diagnosed with sinonasal malignancy. Demographics, tumor staging, and treatment outcomes data are being collected. The Sinonasal Outcome Test-22 and University of Washington Quality of Life Questionnaire are administered at presentation and at recurring intervals. To date, seven institutions are participating nationally.

Conclusion: This prospective, multi-institutional registry will provide novel oncological and QoL outcomes on patients with sinonasal malignancy to inform management decisions and disease prognostication. The application of cloud-based computing facilitates secure multi-institutional collaboration and may serve as a model for future registry development for the study of rare diseases in otolaryngology.

Level Of Evidence: 2C Laryngoscope, 126:1977-1980, 2016.
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http://dx.doi.org/10.1002/lary.25996DOI Listing
September 2016

Abducens Nerve Avulsion and Facial Nerve Palsy After Temporal Bone Fracture: A Rare Concomitance of Injuries.

World Neurosurg 2016 Apr 23;88:689.e5-689.e8. Epub 2015 Dec 23.

Department of Neurosurgery, Stanford University School of Medicine, Stanford, California, USA.

Background: Avulsion of the abducens nerve in the setting of geniculate ganglion injury after temporal bone fracture is unreported previously. We discuss clinical assessment and management of a patient with traumatic avulsion of cranial nerve (CN) VI in the setting of an ipsilateral CN VII injury after temporal bone fracture and call attention to this unusual injury.

Case Description: A 26-year-old man suffered a temporal bone fracture after a motor vehicle accident and developed diplopia and right-sided facial droop. Six weeks after the accident, the patient was readmitted with worsening diplopia and ipsilateral facial weakness. He demonstrated absent lateral gaze on the right suggestive of either restrictive movement or right.

Cn Vi Deficit: In addition, he had right-sided facial palsy graded as 6/6 House-Brackmann. High-resolution computed tomography demonstrated a right-sided longitudinal otic capsule-sparing temporal bone fracture that propagated into the facial nerve canal and geniculate fossa. Magnetic resonance imaging revealed discontinuity of the right CN VI between the pons and the Dorello canal, as well as injury to the ipsilateral geniculate ganglion. CN VII was intact proximally, from the pons through the internal auditory canal. Consensus was reached to proceed with conservative management. At 13 months after injury, the patient reported 1/6 House-Brackmann with no improvement in CN VI function.

Conclusions: This case illustrates 2 subtle findings on imaging with potential therapeutic implications, notably the role of surgical intervention for facial nerve palsy.
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http://dx.doi.org/10.1016/j.wneu.2015.11.076DOI Listing
April 2016

Ameloblastoma: a clinical review and trends in management.

Eur Arch Otorhinolaryngol 2016 Jul 30;273(7):1649-61. Epub 2015 Apr 30.

Division of Head and Neck Surgery, Department of Otolaryngology, Stanford University, 801 Welch Rd., MC 5739, Stanford, CA, 94305, USA.

Ameloblastoma is a rare odontogenic neoplasm of the mandible and maxilla, with multiple histologic variants, and high recurrence rates if improperly treated. The current mainstay of treatment is wide local excision with appropriate margins and immediate reconstruction. Here we review the ameloblastoma literature, using the available evidence to highlight the change in management over the past several decades. In addition, we explore the recent molecular characterization of these tumors which may point towards new potential avenues of personalized treatment.
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http://dx.doi.org/10.1007/s00405-015-3631-8DOI Listing
July 2016

Prognostic value of a qualitative brain MRI scoring system after cardiac arrest.

J Neuroimaging 2015 May-Jun;25(3):430-7. Epub 2014 Jul 15.

Stanford Neurocritical Care Program, Stanford Stroke Center, Stanford University Medical Center, Department of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA.

Background And Purpose: To develop a qualitative brain magnetic resonance imaging (MRI) scoring system for comatose cardiac arrest patients that can be used in clinical practice.

Methods: Consecutive comatose postcardiac arrest patients were prospectively enrolled. Routine MR brain sequences were scored by two independent blinded experts. Predefined brain regions were qualitatively scored on the fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted imaging (DWI) sequences according to the severity of the abnormality on a scale from 0 to 4. The mean score of the raters was used. Poor outcome was defined as death or vegetative state at 6 months.

Results: Sixty-eight patients with 88 brain MRI scans were included. Median time from the arrest to the initial MRI was 77 hours (IQR 58-144 hours). At 100% specificity, the "cortex score" performed best in predicting unfavorable outcome with a sensitivity of 55%-60% (95% CI 41-74) depending on time window selection. When comparing the "cortex score" with historically used predictors for poor outcome, MRI improved the sensitivity for poor outcome over conventional predictors by 27% at 100% specificity.

Conclusions: A qualitative MRI scoring system helps assess hypoxic-ischemic brain injury severity following cardiac arrest and may provide useful prognostic information in comatose cardiac arrest patients.
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http://dx.doi.org/10.1111/jon.12143DOI Listing
February 2016

Association of developmental venous anomalies with perfusion abnormalities on arterial spin labeling and bolus perfusion-weighted imaging.

J Neuroimaging 2015 Mar-Apr;25(2):243-250. Epub 2014 Apr 9.

Department of Radiology, Stanford University and Stanford University Medical Center, Stanford, CA.

Background And Purpose: To investigate the frequency and characteristics of developmental venous anomaly (DVA)-associated perfusion abnormalities on arterial spin labeling (ASL) and bolus perfusion-weighted imaging (PWI) and discuss their potential causes.

Methods: We reviewed brain MR reports to identify all DVAs reported on studies performed between 2009 and 2012. DVA location and findings on PWI and/or ASL imaging were assessed by visual inspection. Sizes of DVAs were categorized as small (<15 mm), medium (15-25 mm), and large (>25 mm). For ASL, signal in the DVA, surrounding parenchyma, or associated draining vein was recorded. For PWI, changes on hemodynamic maps (cerebral blood volume [CBV], cerebral blood flow [CBF], mean transit time [MTT], and normalized time-to-peak of the residue function [Tmax]) were evaluated. Coexisting vascular malformations in association with DVAs were also identified.

Results: Six hundred and fifty-two DVAs were identified in 632 subjects. Of these, 121 underwent both perfusion modalities, 15 only PWI, and 127 only ASL. ASL abnormalities were seen in 21/248 (8%), including signal in a draining vein (2/21, 10%), in the DVA (11/21, 52%), and in the parenchyma (8/21, 38%). On PWI, the majority of DVAs demonstrated abnormalities (108/136, 79%), typically increased CBF, CBV, MTT, and Tmax. There was no association between DVA size and presence of ASL signal (P = .836). Borderline statistical significance was found between DVA size and presence of PWI abnormality (P = .046). No relationship was found between the presence of a coexisting vascular malformation and presence of ASL (P = .468) or PWI abnormality (P = .745).

Conclusions: Perfusion changes with DVAs are common on PWI but uncommon on ASL. PWI findings are expected based on the anatomy and physiology of DVAs and are accentuated by gradient echo acquisition. DVAs with intrinsic ASL signal or signal in draining veins may be associated with arteriovenous shunting (transitional lesions).
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http://dx.doi.org/10.1111/jon.12119DOI Listing
April 2016

Bilateral internal carotid artery occlusion associated with the antiphospholipid antibody syndrome.

Case Rep Neurol 2014 Jan 5;6(1):50-4. Epub 2014 Mar 5.

Department of Neurology and Neurological Sciences and the Stanford Stroke Center, Calif., USA.

A 39-year-old woman presented with a right-hemispheric stroke 1 year after she had suffered a left-hemispheric stroke. Her diagnostic workup was notable for bilateral occlusions of the internal carotid arteries at their origins and a positive lupus anticoagulant antibody test. There was no evidence of carotid dissection or another identifiable cause for her carotid occlusions. These findings suggest that the antiphospholipid antibody syndrome may be implicated in the pathological changes that resulted in occlusions of the extracranial internal carotid arteries. Young stroke patients who present with unexplained internal carotid artery occlusions may benefit from testing for the presence of antiphospholipid antibodies.
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http://dx.doi.org/10.1159/000360473DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3975723PMC
January 2014

Ultrahigh-resolution imaging of the human brain with phase-cycled balanced steady-state free precession at 7 T.

Invest Radiol 2014 May;49(5):278-89

From the Department of Radiology, Stanford University, Stanford, CA.

Objectives: The objectives of this study were to acquire ultra-high resolution images of the brain using balanced steady-state free precession (bSSFP) at 7 T and to identify the potential utility of this sequence.

Materials And Methods: Eight volunteers participated in this study after providing informed consent. Each volunteer was scanned with 8 phase cycles of bSSFP at 0.4-mm isotropic resolution using 0.5 number of excitations and 2-dimensional parallel acceleration of 1.75 × 1.75. Each phase cycle required 5 minutes of scanning, with pauses between the phase cycles allowing short periods of rest. The individual phase cycles were aligned and then averaged. The same volunteers underwent scanning using 3-dimensional (3D) multiecho gradient recalled echo at 0.8-mm isotropic resolution, 3D Cube T2 at 0.7-mm isotropic resolution, and thin-section coronal oblique T2-weighted fast spin echo at 0.22 × 0.22 × 2.0-mm resolution for comparison. Two neuroradiologists assessed image quality and potential research and clinical utility.

Results: The volunteers generally tolerated the scan sessions well, and composite high-resolution bSSFP images were produced for each volunteer. Rater analysis demonstrated that bSSFP had a superior 3D visualization of the microarchitecture of the hippocampus, very good contrast to delineate the borders of the subthalamic nucleus, and relatively good B1 homogeneity throughout. In addition to an excellent visualization of the cerebellum, subtle details of the brain and skull base anatomy were also easier to identify on the bSSFP images, including the line of Gennari, membrane of Liliequist, and cranial nerves. Balanced steady-state free precession had a strong iron contrast similar to or better than the comparison sequences. However, cortical gray-white contrast was significantly better with Cube T2 and T2-weighted fast spin echo.

Conclusions: Balanced steady-state free precession can facilitate ultrahigh-resolution imaging of the brain. Although total imaging times are long, the individually short phase cycles can be acquired separately, improving examination tolerability. These images may be beneficial for studies of the hippocampus, iron-containing structures such as the subthalamic nucleus and line of Gennari, and the basal cisterns and their contents.
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http://dx.doi.org/10.1097/RLI.0000000000000015DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4311399PMC
May 2014

Radiologic assessment of retropharyngeal node involvement in oropharyngeal carcinomas stratified by HPV status.

Radiother Oncol 2013 Nov 5;109(2):293-6. Epub 2013 Oct 5.

Department of Radiation Oncology, Stanford University, USA.

Radiation of retropharyngeal nodes (RPN) results in increased toxicities. This study assessed characteristics associated with RPN involvement in 165 oropharynx cancer patients. Factors associated with involvement were stage N2c-3 disease and stage N2b disease with either advanced T-stage, ⩾3 involved cervical LN, and ⩾1 involved contralateral LN, or lateral/posterior subsites.
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http://dx.doi.org/10.1016/j.radonc.2013.09.001DOI Listing
November 2013

Natural history and prognostic value of corticospinal tract Wallerian degeneration in intracerebral hemorrhage.

J Am Heart Assoc 2013 Aug 2;2(4):e000090. Epub 2013 Aug 2.

Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA.

Background: The purpose of this study was to define the incidence, imaging characteristics, natural history, and prognostic implication of corticospinal tract Wallerian degeneration (CST-WD) in spontaneous intracerebral hemorrhage (ICH) using serial MR imaging.

Methods And Results: Consecutive ICH patients with supratentorial ICH prospectively underwent serial MRIs at 2, 7, 14, and 21 days. MRIs were analyzed by independent raters for the presence and topographical distribution of CST-WD on diffusion-weighted imaging (DWI). Baseline demographics, hematoma characteristics, ICH score, and admission National Institute of Health Stroke Score (NIHSS) were systematically recorded. Functional outcome at 3 months was assessed by the modified Rankin Scale (mRS) and the motor-NIHSS. Twenty-seven patients underwent 93 MRIs; 88 of these were serially obtained in the first month. In 13 patients (48%), all with deep ICH, CST-WD changes were observed after a median of 7 days (interquartile range, 7 to 8) as reduced diffusion on DWI and progressed rostrocaudally along the CST. CST-WD changes evolved into T2-hyperintense areas after a median of 11 days (interquartile range, 6 to 14) and became atrophic on MRIs obtained after 3 months. In univariate analyses, the presence of CST-WD was associated with poor functional outcome (ie, mRS 4 to 6; P=0.046) and worse motor-NIHSS (5 versus 1, P=0.001) at 3 months.

Conclusions: Wallerian degeneration along the CST is common in spontaneous supratentorial ICH, particularly in deep ICH. It can be detected 1 week after ICH on DWI and progresses rostrocaudally along the CST over time. The presence of CST-WD is associated with poor motor and functional recovery after ICH.
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http://dx.doi.org/10.1161/JAHA.113.000090DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3828779PMC
August 2013

Improved sleep MRI at 3 tesla in patients with obstructive sleep apnea.

J Magn Reson Imaging 2013 Nov 6;38(5):1261-6. Epub 2013 Feb 6.

Department of Radiology, Stanford University, Stanford, California, USA; VA Palo Alto Health Care System, Palo Alto, California, USA.

Purpose: To describe a real-time MR imaging platform for synchronous, multi-planar visualization of upper airway collapse in obstructive sleep apnea at 3 Tesla (T) to promote natural sleep with an emphasis on lateral wall visualization.

Materials And Methods: A real-time imaging platform was configured for sleep MR imaging which used a cartesian, partial k-space gradient-echo sequence with an inherent temporal resolution of 3 independent slices every 2 s. Combinations of axial, mid-sagittal, and coronal scan planes were acquired. The system was tested in five subjects with polysomnography-proven obstructive sleep apnea during sleep, with synchronous acquisition of respiratory effort and combined oral-nasal airflow data.

Results: Sleep was initiated and maintained to allow demonstration of sleep-induced, upper airway collapse as illustrated in two subjects when using a real-time, sleep MR imaging platform at 3T. Lateral wall collapse could not be visualized on mid-sagittal imaging alone and was best characterized on multiplanar coronal and axial imaging planes.

Conclusion: Our dedicated sleep MR imaging platform permitted an acoustic environment of constant "white noise" which was conducive to sleep onset and sleep maintenance in obstructive sleep apnea patients at 3T. Apneic episodes, specifically the lateral walls, were more accurately characterized with synchronous, multiplanar acquisitions.
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http://dx.doi.org/10.1002/jmri.24029DOI Listing
November 2013

Impact of positron emission tomography/computed tomography surveillance at 12 and 24 months for detecting head and neck cancer recurrence.

Cancer 2013 Apr 7;119(7):1349-56. Epub 2012 Dec 7.

Department of Otolaryngology-Head and Neck Surgery, Stanford University School of Medicine, Palo Alto, CA, USA.

Background: In head and neck cancer (HNC), 3-month post-treatment positron emission tomography (PET)/computed tomography (CT) reliably identifies persistent/recurrent disease. However, further PET/CT surveillance has unclear benefit. The impact of post-treatment PET/CT surveillance on outcomes is assessed at 12 and 24 months.

Methods: A 10-year retrospective analysis of HNC patients was carried out with long-term serial imaging. Imaging at 3 months included either PET/CT or magnetic resonance imaging, with all subsequent imaging comprised of PET/CT. PET/CT scans at 12 and 24 months were evaluated only if preceding interval scans were negative. Of 1114 identified patients, 284 had 3-month scans, 175 had 3- and 12-month scans, and 77 had 3-, 12-, and 24-month scans.

Results: PET/CT detection rates in clinically occult patients were 9% (15 of 175) at 12 months, and 4% (3 of 77) at 24 months. No difference in outcomes was identified between PET/CT-detected and clinically detected recurrences, with similar 3-year disease-free survival (41% vs 46%, P = .91) and 3-year overall survival (60% vs 54%, P = .70) rates. Compared with 3-month PET/CT, 12-month PET/CT demonstrated fewer equivocal reads (26% vs 10%, P < .001). Of scans deemed equivocal, 6% (5 of 89) were ultimately found to be positive.

Conclusions: HNC patients with negative 3-month imaging appear to derive limited benefit from subsequent PET/CT surveillance. No survival differences were observed between PET/CT-detected and clinically detected recurrences, although larger prospective studies are needed for further investigation.
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http://dx.doi.org/10.1002/cncr.27892DOI Listing
April 2013

Moyamoya disease can masquerade as multiple sclerosis.

Neurologist 2012 Nov;18(6):398-403

Departments of Neurology and Neurological Sciences, Stanford University School of Medicine, Stanford, CA, USA.

Background: Moyamoya disease (MM) is a rare disorder of the cerebral arterial circulation, whereas multiple sclerosis (MS) is a relatively common immune-mediated attack on central myelin. Despite the differences in pathogenesis, the 2 disorders share some clinical features which can lead to diagnostic confusion: both can affect young adults, cause intermittent neurological symptoms, and show multifocal abnormalities on brain imaging.

Objective: To emphasize the need for early consideration of MM in the differential diagnosis of MS-spectrum disorders.

Methods: Chart reviews and individual case analyses.

Results: We present detailed descriptions of 3 patients with MM, and summary data on 8 additional cases, in which there was diagnostic confusion with MS, with delays in treatment ranging from 2 months to 19 years (median=4 y).

Conclusions: MM can be misdiagnosed as MS, leading to delay in correct treatment. We highlight the clinical and radiologic features which allow differentiation of these conditions early in the course, when treatment can have maximum benefit.
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http://dx.doi.org/10.1097/NRL.0b013e31826a99a1DOI Listing
November 2012

Evaluating the utility of non-echo-planar diffusion-weighted imaging in the preoperative evaluation of cholesteatoma: a meta-analysis.

Laryngoscope 2013 May 28;123(5):1247-50. Epub 2012 Sep 28.

Department of Otolaryngology-Head and Neck Surgery, Stanford University, Stanford, California 94305-5739, USA.

Objectives/hypothesis: To describe the accuracy of non-echo-planar diffusion-weighted magnetic resonance imaging (DW MRI) in identifying middle ear cholesteatoma.

Study Design: A meta-analysis of the published literature.

Methods: A systematic review of the literature was performed to identify studies in which patients suspected of having middle ear cholesteatoma underwent DW MRI scans prior to surgery. A meta-analysis of the included studies was performed.

Results: Ten published articles (342 patients) met inclusion criteria. Cholesteatoma was confirmed in 234 patients, of which 204 were detected by DW MRI (true positives) and 30 were not (false negatives). One hundred eight patients did not have cholesteatoma on surgical examination, and of these 100 were correctly identified by MRI (true negatives) whereas eight were not (false positives). The overall sensitivity of DW MRI in detecting cholesteatoma was 0.94 (confidence interval, 0.80-0.98) and specificity 0.94 (confidence interval, 0.85-0.98). DW MRI sequences could not reliably detect cholesteatomas under 3 mm in size.

Conclusions: Non-echo-planar DW MRI is highly sensitive and specific in identifying middle ear cholesteatoma. DW MRI may help to stratify patients into groups of who would benefit from early second-look surgery and those who could be closely observed.

Level Of Evidence: 2a.
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http://dx.doi.org/10.1002/lary.23759DOI Listing
May 2013

Arterial spin labeling imaging findings in transient ischemic attack patients: comparison with diffusion- and bolus perfusion-weighted imaging.

Cerebrovasc Dis 2012 19;34(3):221-8. Epub 2012 Sep 19.

Department of Radiology, Stanford University, Stanford, CA 94305-5488, USA.

Background: Since transient ischemic attacks (TIAs) can predict future stroke, it is important to distinguish true vascular events from non-vascular etiologies. Arterial spin labeling (ASL) is a non-contrast magnetic resonance (MR) method that is sensitive to cerebral perfusion and arterial arrival delays. Due to its high sensitivity to minor perfusion alterations, we hypothesized that ASL abnormalities would be identified frequently in TIA patients, and could therefore help increase clinicians' confidence in the diagnosis.

Methods: We acquired diffusion-weighted imaging (DWI), intracranial MR angiography (MRA), and ASL in a prospective cohort of TIA patients. A subset of these patients also received bolus contrast perfusion-weighted imaging (PWI). Two neuroradiologists evaluated the images in a blinded fashion to determine the frequency of abnormalities on each imaging sequence. Kappa (ĸ) statistics were used to assess agreement, and the χ(2) test was used to detect differences in the proportions of abnormal studies.

Results: 76 patients met the inclusion criteria, 48 (63%) of whom received PWI. ASL was abnormal in 62%, a much higher frequency compared with DWI (24%) and intracranial MRA (13%). ASL significantly increased the MR imaging yield above the combined DWI and MRA yield (62 vs. 32%, p < 0.05). Arterial transit artifact in vascular borderzones was the most common ASL abnormality (present in 51%); other abnormalities included focal high or low ASL signal (11%). PWI was abnormal in 31% of patients, and in these, ASL was abnormal in 14 out of 15 cases (93%). In hemispheric TIA patients, both PWI and ASL findings were more common in the symptomatic hemisphere. Agreement between neuroradiologists regarding abnormal studies was good for ASL and PWI [ĸ = 0.69 (95% CI 0.53-0.86) and ĸ = 0.66 (95% CI 0.43-0.89), respectively].

Conclusion: In TIA patients, perfusion-related alterations on ASL were more frequently detected compared with PWI or intracranial MRA and were most frequently associated with the symptomatic hemisphere. Almost all cases with a PWI lesion also had an ASL lesion. These results suggest that ASL may aid in the workup and triage of TIA patients, particularly those who cannot undergo a contrast study.
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http://dx.doi.org/10.1159/000339682DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7309636PMC
March 2013

Cryptococcal osteomyelitis and meningitis in a patient with non-hodgkin's lymphoma treated with PEP-C.

BMJ Case Rep 2012 Sep 7;2012. Epub 2012 Sep 7.

Department of Internal Medicine, Scripps Clinic/Green Hospital, La Jolla, California, USA.

The authors present the first case report of a patient with lymphoma who developed disseminated cryptococcal osteomyelitis and meningitis while being treated with the PEP-C (prednisone, etoposide, procarbazine and cyclophosphamide) chemotherapy regimen. During investigation of fever and new bony lesions, fungal culture from a rib biopsy revealed that the patient had cryptococcal osteomyelitis. Further evaluation demonstrated concurrent cryptococcal meningitis. The patient's disseminated cryptococcal infections completely resolved after a full course of antifungal treatment. Cryptococcal osteomyelitis is itself an extremely rare diagnosis, and the unique presentation with concurrent cryptococcal meningitis in our patient with lymphoma was likely due to his PEP-C treatment. It is well recognised that prolonged intensive chemotherapeutic regimens place patients at risk for atypical infections; yet physicians should recognise that even chronic low-dose therapies can put patients at risk for fungal infections. Physicians should consider fungal infections as part of the infectious investigation of a lymphopaenic patient on PEP-C.
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http://dx.doi.org/10.1136/bcr.08.2011.4578DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3448757PMC
September 2012

Radiographic evaluation of the tegmen in patients with superior semicircular canal dehiscence.

Otol Neurotol 2012 Sep;33(7):1245-50

Department of Otolaryngology-Head and Neck Surgery, Stanford University, Stanford, California 94305-5739, USA.

Objective: To determine a radiographic association between superior semicircular canal dehiscence (SSCD) and tegmen dehiscence (TD).

Study Design: Retrospective case-control series.

Setting: Tertiary referral center.

Patients: Patients seen between 2003 and 2010 with radiographic SSCD were compared with cochlear implant recipient controls.

Intervention: The tegmen and superior semicircular canal were evaluated on computed tomographic temporal bone scans.

Main Outcome Measure: If detected, the widest point of the SSCD was measured. The tegmen was graded on a 5-point scale. After analysis, a radiographic TD was defined as any single area of absent tegmen greater than 5 mm, multiple areas of absent tegmen, or evidence of meningocele. Age, sex, and body mass index were also noted.

Results: Thirty-eight patients with SSCD and 41 cochlear implant controls were identified. Seventy-six percent (29/38) of patients with unilateral or bilateral SSCD had a radiographic TD on at least 1 side compared with 22% (9/41) of the comparison group. Ninety-four percent (7/18) of patients with bilateral SSCD had a TD on at least 1 side. Patients with SSCD had a 10.2 times (p < 0.001) higher odds of having radiographic TD in either ear compared to the controls. Among patients with any SSCD, for every millimeter increase in the width of dehiscence, the relative risk for any TD increased more than 2-fold (odds ratio, 2.5; p = 0.019). Age, sex, and a body mass index greater than 30 did not confound the association between SSCD and TD.

Conclusion: There is a strong radiologic association between SSCD and TD, suggesting a similar etiologic process. The tegmen should be carefully evaluated in patients with SSCD. We have also proposed a new system for radiographically grading the integrity of the tegmen.
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http://dx.doi.org/10.1097/MAO.0b013e3182634e27DOI Listing
September 2012

Stereotactic radiosurgery for retreatment of gross perineural invasion in recurrent cutaneous squamous cell carcinoma of the head and neck.

Am J Clin Oncol 2013 Jun;36(3):293-8

Department of Radiation Oncology, Division of Medical Oncology, Stanford University, Stanford, CA, USA.

Objectives: To report outcomes, failure patterns, and toxicity after stereotactic radiosurgery (SRS) for recurrent head and neck cutaneous squamous cell carcinoma with gross perineural invasion (GPNI).

Methods: Ten patients who received SRS as part of retreatment for recurrent head and neck cutaneous squamous cell carcinoma with GPNI were included. All patients exhibited clinical and radiologic evidence of GPNI before SRS. Previous treatments included surgery alone in 3 patients and surgery with adjuvant external beam radiotherapy (EBRT) in 7 patients. Retreatment included SRS alone in 2 and EBRT boosted with SRS in 8 patients. Magnetic resonance images were obtained every 3 to 6 months after SRS to track failure patterns.

Results: At a median 22-month follow-up, the 2-year progression-free and overall survival rates were 20% and 50%, respectively. Seven patients exhibited local failures, all of which occurred outside both SRS and EBRT fields. Five local failures occurred in previously clinically uninvolved cranial nerves (CNs). CN disease spreads through 3 distinct patterns: among different branches of CN V; between CNs V and VII; and between V1 and CNs III, IV, and/or VI. Five patients experienced side effects potentially attributable to radiation.

Conclusions: Although there is excellent in-field control with this approach, the rate of out-of-field failures remains unacceptably high. We found that the majority of failures occurred in previously clinically uninvolved CNs often just outside treatment fields. Novel treatment strategies targeting this mode of perineural spread are needed.
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http://dx.doi.org/10.1097/COC.0b013e3182468019DOI Listing
June 2013

Comparison of arterial spin labeling and bolus perfusion-weighted imaging for detecting mismatch in acute stroke.

Stroke 2012 Jul 26;43(7):1843-8. Epub 2012 Apr 26.

Department of Radiology, Stanford University Medical Center, 1201 Welch Road, Mailcode 5488, Stanford, CA 94305-5488, USA.

Background And Purpose: The perfusion-weighted imaging (PWI)-diffusion-weighted imaging (DWI) mismatch paradigm is widely used in stroke imaging studies. Arterial spin labeling (ASL) is an alternative perfusion method that does not require contrast. This study compares the agreement of ASL-DWI and PWI-DWI mismatch classification in patients with stroke.

Methods: This was a retrospective study drawn from all 1.5-T MRI studies performed in 2010 at a single institution. Inclusion criteria were: symptom onset<5 days, DWI lesion>10 mL, and acquisition of both PWI and ASL. DWI and PWI time to maximum>6 seconds lesion volumes were determined using automated software. Patients were classified into reperfused, matched, or mismatch groups. Two radiologists classified ASL-DWI qualitatively into the same categories blinded to DWI-PWI. Agreement between both individual readers and methods was assessed.

Results: Fifty-one studies met the inclusion criteria. Seven cases were excluded (1 due to PWI susceptibility artifact, 2 due to motion, and 4 due to severe ASL border zone sign), resulting in 44 studies for comparison. Interrater agreement for ASL-DWI mismatch status was high (κ=0.92; 95% CI, 0.80-1.00). ASL-DWI and PWI-DWI mismatch categories agreed in 25 of 44 cases (57%). In the 16 of 19 discrepant cases (84%), ASL overestimated the PWI lesion size. In 34 of 44 cases (77%), they agreed regarding the presence of mismatch versus no mismatch.

Conclusions: Mismatch classification based on ASL and PWI agrees frequently but not perfectly. ASL tends to overestimate the PWI time to maximum lesion volume. Improved ASL methodologies and/or higher field strength are necessary before ASL can be recommended for routine use in acute stroke.
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http://dx.doi.org/10.1161/STROKEAHA.111.639773DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3383868PMC
July 2012

Validation that metabolic tumor volume predicts outcome in head-and-neck cancer.

Int J Radiat Oncol Biol Phys 2012 Aug 21;83(5):1514-20. Epub 2012 Jan 21.

Department of Radiation Oncology, Stanford University, Stanford, CA, USA.

Purpose: We have previously reported that metabolic tumor volume (MTV) obtained from pretreatment (18)F-fluorodeoxydeglucose positron emission tomography (FDG PET)/ computed tomography (CT) predicted outcome in patients with head-and-neck cancer (HNC). The purpose of this study was to validate these results on an independent dataset, determine whether the primary tumor or nodal MTV drives this correlation, and explore the interaction with p16(INK4a) status as a surrogate marker for human papillomavirus (HPV).

Methods And Materials: The validation dataset in this study included 83 patients with squamous cell HNC who had a FDG PET/CT scan before receiving definitive radiotherapy. MTV and maximum standardized uptake value (SUV(max)) were calculated for the primary tumor, the involved nodes, and the combination of both. The primary endpoint was to validate that MTV predicted progression-free survival and overall survival. Secondary analyses included determining the prognostic utility of primary tumor vs. nodal MTV.

Results: Similarly to our prior findings, an increase in total MTV of 17 cm(3) (difference between the 75th and 25th percentiles) was associated with a 2.1-fold increase in the risk of disease progression (p = 0.0002) and a 2.0-fold increase in the risk of death (p = 0.0048). SUV(max) was not associated with either outcome. Primary tumor MTV predicted progression-free (hazard ratio [HR] = 1.94; p < 0.0001) and overall (HR = 1.57; p < 0.0001) survival, whereas nodal MTV did not. In addition, MTV predicted progression-free (HR = 4.23; p < 0.0001) and overall (HR = 3.21; p = 0.0029) survival in patients with p16(INK4a)-positive oropharyngeal cancer.

Conclusions: This study validates our previous findings that MTV independently predicts outcomes in HNC. MTV should be considered as a potential risk-stratifying biomarker in future studies of HNC.
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http://dx.doi.org/10.1016/j.ijrobp.2011.10.023DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3337958PMC
August 2012