Publications by authors named "Goodarz Golmirzaie"

5 Publications

  • Page 1 of 1

Brain network motifs are markers of loss and recovery of consciousness.

Sci Rep 2021 Feb 16;11(1):3892. Epub 2021 Feb 16.

School of Physical and Occupational Therapy, McGill University, Montreal, Canada.

Motifs are patterns of inter-connections between nodes of a network, and have been investigated as building blocks of directed networks. This study explored the re-organization of 3-node motifs during loss and recovery of consciousness. Nine healthy subjects underwent a 3-h anesthetic protocol while 128-channel electroencephalography (EEG) was recorded. In the alpha (8-13 Hz) band, 5-min epochs of EEG were extracted for: Baseline; Induction; Unconscious; 30-, 10- and 5-min pre-recovery of responsiveness; 30- and 180-min post-recovery of responsiveness. We constructed a functional brain network using the weighted and directed phase lag index, on which we calculated the frequency and topology of 3-node motifs. Three motifs (motifs 1, 2 and 5) were significantly present across participants and epochs, when compared to random networks (p < 0.05). The topology of motifs 1 and 5 changed significantly between responsive and unresponsive epochs (p-values < 0.01; Kendall's W = 0.664 (motif 1) and 0.529 (motif 5)). Motif 1 was constituted of long-range chain-like connections, while motif 5 was constituted of short-range, loop-like connections. Our results suggest that anesthetic-induced unconsciousness is associated with a topological re-organization of network motifs. As motif topological re-organization may precede (motif 5) or accompany (motif 1) the return of responsiveness, motifs could contribute to the understanding of the neural correlates of consciousness.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1038/s41598-021-83482-9DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7887248PMC
February 2021

Access to Multimodal Pain Management for Patients with Chronic Pain: an Audit Study.

J Gen Intern Med 2021 Mar 6;36(3):818-820. Epub 2020 May 6.

Center for Clinical Management and Research, Ann Arbor VA Hospital, Ann Arbor, MI, USA.

View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1007/s11606-020-05866-3DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7947134PMC
March 2021

Phenotypic features of patients with complex regional pain syndrome compared with those with neuropathic pain.

Reg Anesth Pain Med 2019 Jul 5. Epub 2019 Jul 5.

Department of Anesthesiology, University of Michigan, Ann Arbor, Michigan, USA

Introduction: We hypothesized that patients with complex regional pain syndrome (CRPS) would describe a more negative pain phenotype including higher pain severity, more neuropathic pain descriptors, more centralized pain symptoms, poorer physical function, and more affective distress when compared with patients with neuropathic pain of the extremities not meeting CRPS criteria.

Materials And Methods: This was a retrospective cross-sectional study conducted at a tertiary pain center. The sample included 212 patients who met Budapest Criteria for CRPS and 175 patients with neuropathic pain of the extremities who did not meet criteria. All patients completed a packet of questionnaires before their initial visit containing validated outcome measures assessing pain severity, pain interference, physical functioning, depression, anxiety, and catastrophizing.

Results: Patients with CRPS reported higher physical disability (p=0.022) and more neuropathic pain symptoms (p=0.002) than patients not meeting CRPS criteria, but the groups did not otherwise differ significantly. There were no significant differences in pain severity or affective distress, despite power analyses suggesting the ability to detect small to medium effect sizes (d=0.29; w=0.14). Subanalyses of differences in neuropathic pain symptoms revealed that patients with CRPS, compared with patients not meeting CRPS criteria, were more likely to report pain with light touch (p=0.003), sudden pain attacks (p=0.003), pain with cold or heat (p=0.002), sensation of numbness (p=0.042), and pain with slight pressure (p=0.018).

Discussion: Counter to our hypothesis, the present study suggests that patients with CRPS do not have a worse clinical phenotype compared with patients not meeting CRPS criteria, with the exception of higher physical disability and more neuropathic pain symptoms. This corresponds to recent evidence that patients with CRPS are similar to other patient populations with chronic pain.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1136/rapm-2019-100511DOI Listing
July 2019

Network Efficiency and Posterior Alpha Patterns Are Markers of Recovery from General Anesthesia: A High-Density Electroencephalography Study in Healthy Volunteers.

Front Hum Neurosci 2017 28;11:328. Epub 2017 Jun 28.

Center for Consciousness Science, University of Michigan Medical SchoolAnn Arbor, MI, United States.

Recent studies have investigated local oscillations, long-range connectivity, and global network patterns to identify neural changes associated with anesthetic-induced unconsciousness. These studies typically employ anesthetic protocols that either just cross the threshold of unconsciousness, or induce deep unconsciousness for a brief period of time-neither of which models general anesthesia for major surgery. To study neural patterns of unconsciousness and recovery in a clinically-relevant context, we used a realistic anesthetic regimen to induce and maintain unconsciousness in eight healthy participants for 3 h. High-density electroencephalogram (EEG) was acquired throughout and for another 3 h after emergence. Seven epochs of 5-min eyes-closed resting states were extracted from the data at baseline as well as 30, 60, 90, 120, 150, and 180-min post-emergence. Additionally, 5-min epochs were extracted during induction, unconsciousness, and immediately prior to recovery of consciousness, for a total of 10 analysis epochs. The EEG data in each epoch were analyzed using source-localized spectral analysis, phase-lag index, and graph theoretical techniques. Posterior alpha power was significantly depressed during unconsciousness, and gradually approached baseline levels over the 3 h recovery period. Phase-lag index did not distinguish between states of consciousness or stages of recovery. Network efficiency was significantly depressed and network clustering coefficient was significantly increased during unconsciousness; these graph theoretical measures returned to baseline during the 3 h recovery period. Posterior alpha power may be a potential biomarker for normal recovery of functional brain networks after general anesthesia.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.3389/fnhum.2017.00328DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC5487412PMC
June 2017

Time Since Inciting Event Is Associated With Higher Centralized Pain Symptoms in Patients Diagnosed With Complex Regional Pain Syndrome.

Reg Anesth Pain Med 2016 Nov/Dec;41(6):731-736

From the Division of Pain Medicine and the Back and Pain Center, Department of Anesthesiology, University of Michigan, Ann Arbor, MI.

Background And Objectives: We hypothesized that patients with complex regional pain syndrome (CRPS) with a longer time since their inciting event would demonstrate more symptoms of centralized pain.

Methods: We conducted a cross-sectional analysis of 160 patients with CRPS using validated measures of pain, negative mood, and functioning at the time of their new patient evaluation. The 2011 Fibromyalgia Survey Criteria is a validated self-report measure of widespread body pain and comorbid symptoms (eg, trouble thinking, headaches). The measure was used as a surrogate for centralized pain symptoms. Univariate analyses and multivariate linear regression models were used to assess the associations between patient characteristics and the duration of CRPS.

Results: The cohort was divided into tertiles based on the time since the inciting event (<12 months; 1-3 years; >3 years) for univariate comparisons. Unlike the other measures of pain, mood, and function, the fibromyalgia survey score was significantly associated with a longer duration of symptoms. In a multivariate model adjusting for age and sex, each year since the inciting event was associated with an increase of 0.28 in fibromyalgia survey score (Est 0.28; 95% confidence interval, 0.11-0.46; P = 0.002). The finding was distinct from self-reported spread of CRPS symptoms, which was not different based on time since the inciting event.

Conclusions: Our findings suggest that the longer the patients have CRPS the more likely they are to report symptoms suggestive of centralized pain. These data may explain why some patients with a longer duration of CRPS do not respond to peripherally directed therapies.
View Article and Find Full Text PDF

Download full-text PDF

Source
http://dx.doi.org/10.1097/AAP.0000000000000483DOI Listing
April 2018