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Dive into the research topics where Shahram Majidi is active.

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Featured researches published by Shahram Majidi.


Stroke | 2011

The ABCs of Accurate Volumetric Measurement of Cerebral Hematoma

Afshin A. Divani; Shahram Majidi; Xianghua Luo; Fotis Souslian; Jie Zhang; Aviva Abosch; Ramachandra P. Tummala

Background and Purpose— Both initial hematoma volume and hematoma growth are independent predictors of clinical outcomes and mortality among intracerebral hemorrhage patients. The purpose of this study was to evaluate the accuracy of different computed tomography image acquisition protocols and hematoma volume measurement techniques. Methods— We used plastic and cadaveric phantoms to determine the accuracy of different volumetric measurement techniques. We performed both axial and spiral computed tomography scans with 0.75-, 1.5-, 3.0-, and 4.5-mm-thick transverse sections (with no gap). Different measurement techniques (planimetry, ABC/2, and 3D rendering) and different window width/level settings (I, 150/50 versus II, 587/−321) were used to assess generated errors in volumetric calculations. Results— Both axial and spiral computed tomography scans yielded similar percent errors for different slice thicknesses and different measurement techniques. Comparison of different measurement techniques revealed a significant difference in measurement error only from the ABC/2 method as compared with 3D-rendering measurements (P<0.0001). The overall measurement error according to the ABC/2 method was further increased by ≈8% for irregularly shaped hematomas (P=0.0004). A significant percent difference in measurement error was observed between window width/levels I and II for both planimetry (mean difference across all thicknesses, 1.91±3.78, P=0.004) and Analyze software (mean difference across all thicknesses, 6.92±7.29, P<0.0001) methods. Conclusions— A better understanding of the limitations that may affect measurement of hematoma volume is crucial in the assessment of hematoma volume, which is considered an independent marker of clinical outcome.


Stroke | 2011

Consequences of Stroke in Community-Dwelling Elderly The Health and Retirement Study, 1998 to 2008

Afshin A. Divani; Shahram Majidi; Anna M. Barrett; Siamak Noorbaloochi; Andreas R. Luft

Background and Purpose— Stroke survivors are at risk of developing comorbidities that further reduce their quality of life. The purpose of this study was to determine the risk of developing a secondary health problem after stroke. Methods— We performed a case–control analysis using 6 biennial interview waves (1998 to 2008) of the Health and Retirement Study. We compared 631 noninstitutionalized individuals who had a single stroke with 631 control subjects matched for age, gender, and interview wave. We studied sleep problems, urinary incontinence, motor impairment, falls, and memory deficits among the 2 groups. Results— Stroke survivors frequently developed new or worsened motor impairment (33%), sleep problems (up to 33%), falls (30%), urinary incontinence (19%), and memory deficits (9%). As compared with control subjects, the risk of developing a secondary health problem was highest for memory deficits (OR, 2.45; 95% CI, 1.34 to 4.46) followed by urinary incontinence (OR, 1.86; 95% CI, 1.31 to 2.66), motor impairment (OR, 1.61; 95% CI, 1.16 to 2.24), falls (OR, 1.5; 95% CI, 1.12 to 2.0), and sleep disturbances (OR, 1.49; 95% CI, 1.09 to 2.03). In contrast, stroke survivors were not more likely to injure themselves during a fall (OR, 1.14; 95% CI, 0.72 to 1.79). After adjusting for cardiovascular risk factors, social status, psychiatric symptoms, and pain, the risks of falling or developing sleep problems were not different from the control subjects. Conclusions— The risk of developing a secondary health problem that can impact daily life is markedly increased after stroke. A better understanding of frequencies and risks for secondary health problems after stroke is necessary for designing better preventive and rehabilitation strategies.


Journal of Vascular Surgery | 2012

A comparison of outcomes associated with carotid artery stent placement performed within and outside clinical trials in the United States

Adnan I. Qureshi; Saqib A Chaudhry; Haitham M. Hussein; Shahram Majidi; Rakesh Khatri; Gustavo J. Rodriguez; M. Fareed K. Suri

BACKGROUND A discrepancy between characteristics of patients treated with carotid angioplasty and stent placement (CAS) within and outside clinical trials, particularly characteristics with direct impact on clinical outcome, may limit generalization of clinical trial results. The objective of this study was to identify differences in demographic and clinical characteristics and outcomes related to CAS in patients treated within clinical trials and those treated outside clinical trials in a large national cohort. METHODS We determined the frequency of CAS performed within and outside clinical trials and associated in-hospital outcomes using data from the Nationwide Inpatient Survey data files from 2005 to 2009. All the in-hospital outcomes were analyzed after adjusting for potential confounders using multivariate analysis. RESULTS Of the 81,638 patients who underwent CAS, 16,078 (19.6%) underwent the procedure as part of a clinical trial. The mean age of the patients was significantly lower in patients treated with CAS as part of a clinical trial than those treated with CAS outside a clinical trial. The proportion of women and nonwhites was lower among patients treated with CAS as part of a clinical trial. The in-hospital mortality was two-fold higher among patients treated with CAS outside clinical trials (1.12% vs 0.53%; P = .0005). The rate of composite endpoint of stroke, cardiac events, and death was significantly higher among patients treated with CAS outside clinical trials (P = .02). After adjusting for age, gender, presence of renal failure, and hospital bed size, CAS performed as part of a clinical trial was associated with lower rates of in-hospital mortality (odds ratio, 0.467; 95% confidence interval, 0.290-0.751; P = .0017) and composite endpoint of stroke, cardiac events, and death (odds ratio, 0.752; 95% confidence interval, 0.594-0.952; P = .0180). CONCLUSIONS Our results suggest that CAS procedures performed as part of clinical trials was associated with lower rates of in-hospital mortality and composite endpoint of stroke, cardiac events, and death in United States. These findings highlight the need for strategies that ensure appropriate adoption of CAS to ensure that the benefits observed in clinical trials can be replicated in general practice.


Journal of Stroke & Cerebrovascular Diseases | 2013

Validation of intracerebral hemorrhage-specific intensity of care quality metrics.

Adnan I. Qureshi; Shahram Majidi; Saqib A Chaudhry; Mushtaq Qureshi; M. Fareed K. Suri

BACKGROUND Given the considerable variation in care of patients with intracerebral hemorrhage (ICH) among centers that results in differences in outcome among these patients, a new intensity of care quality metrics has been proposed. This study aimed to validate the new ICH-specific intensity of care quality metrics. METHODS A total of 50 consecutive patients with ICH who were admitted within 24 hours of symptom onset were identified. Twenty-six quality indicators related to 18 facets of care were incorporated into a metric providing the variable, definition of the variable, and quality parameter. A score of 1 point was assigned if the quality parameter met the threshold for appropriate performance or if the parameter was not applicable, creating a total score of up to 26 points. The predictive validity of the classification scheme was tested by using the bootstrap method. RESULTS Fourteen of the 50 patients with ICH died during hospitalization (28%). The intensity of care quality metric score ranged from 17 points to 26 points. The mean score was higher in those who survived compared with those who died (23 ± 3 vs 21 ± 2; P = .02). Survival increased with tertile based on higher scores (100%, 67%, and 55%; P = .017). The receiver operating characteristic curve demonstrated a high discriminating ability of intensity of care quality metrics for in-hospital mortality (0.730, 95% confidence interval, 0.591-0.869) and a C-statistic of 0.91 (95% confidence interval, 0.90-0.92). CONCLUSIONS Correlation of the new ICH-specific intensity of care quality metric with in-hospital mortality supports its broader use for improving and standardizing medical care among patients with ICH.


Neuroepidemiology | 2012

Population-based estimates of neuroendovascular procedures: results of a state-wide study.

Adnan I. Qureshi; Saqib A Chaudhry; Shahram Majidi; Mikayel Grigoryan; Gustavo J. Rodriguez; M. Suri

Background: The Brain Attack Coalition identified the availability of neuroendovascular procedures as an essential component of a comprehensive stroke center. Objective: To provide population-based estimates of neuroendovascular procedures. Methods: State-wide estimates of cervicocerebral angiograms, endovascular ischemic stroke treatments, carotid angioplasty and stent placements, intracranial angioplasty and stent placements, endovascular treatment of intracranial aneurysms, and endovascular treatment of intracranial arteriovenous malformations (AVMs) were obtained. We calculated the annual incidence rates of various neuroendovascular and neurosurgical procedures (per 100,000 persons). For the denominator, total persons in each year were categorized in 10-year age intervals. Results: The incidence of carotid endarterectomy (387.6 per 100,000 persons) and carotid stent placement (34.7 per 100,000 persons) peaked at 75–84 years. The incidence of aneurysm embolization also peaked in that population bracket (67.9 per 100,000 persons), yet there was a dramatic reduction in the incidence of surgical aneurysm treatment (3.6 per 100,000 persons) in those aged 75–84 years. There was a prominent reduction in the incidence of all procedures in the population aged ≥85 years, except for intravenous/intra-arterial thrombolytic use in ischemic stroke. The incidence of ischemic stroke increased almost by 50% in the population aged ≥85 years compared to those aged 75–84 years. However, the incidence of endovascular procedures for acute ischemic stroke decreased from 22.8 per 100,000 persons in the population aged 75–84 years to 13.2 per 100,000 persons in the population aged ≥85 years. Conclusions: A marked disproportion of neuroendovascular procedures performed and disease prevalence was noted in persons aged ≥85 years, an increasing segment of the population according to recent Census.


Journal of Neurosurgery | 2013

A 2-fold higher rate of intraventricular hemorrhage–related mortality in African American neonates and infants

Adnan I. Qureshi; Malik M Adil; Negin Shafizadeh; Shahram Majidi

OBJECT Despite the recognition of racial or ethnic differences in preterm gestation, such differences in the rate of intraventricular hemorrhage (IVH), frequently associated with preterm gestation, are not well studied. The authors performed the current study to identify racial or ethnic differences in the incidence of IVH-related mortality within the national population of the US. METHODS Using the ICD-10 codes P52.0, P52.1, P52.2, P52.3, and P10.2 and the Multiple Cause of Death data from 2000 to 2009, the authors identified all IVH-related mortalities that occurred in neonates and infants aged less than 1 year. The live births for whites and African Americans from the census for 2000-2009 were used to derive the incidence of IVH-related mortality for whites and African Americans per 100,000 live births. The IVH rate ratio (RR, 95% confidence interval [CI]) and annual percent change (APC) in the incidence rates from 2000 to 2009 were also calculated. RESULTS A total of 3249 IVH-related mortality cases were reported from 2000 to 2009. The incidence rates of IVH were higher among African American infants (16 per 100,000 live births) than among whites (7.8 per 100,000 live births). African American infants had a 2-fold higher risk of IVH-related mortality compared with whites (RR 2.0, 95% CI 1.2-3.2). The rate of increase over the last 10 years was less in African American infants (APC 1.6%) than in white infants (APC 4.3%). CONCLUSIONS The rate of IVH-related mortality is 2-fold higher among African American than white neonates and infants. Further studies are required to understand the underlying reasons for this prominent disparity in one of the most significant causes of infant mortality.


Neurosurgery | 2012

Aneurysm embolization using detachable coils under intravascular ultrasonography guidance: an in vitro feasibility study.

Shahram Majidi; Rakesh Khatri; Masaki Watanabe; Farhan Siddiq; Saqib A Chaudhry; Adnan I. Qureshi

BACKGROUND Intravascular ultrasonography (IVUS) has been used for guiding intravascular stent placement in interventional cardiology. OBJECTIVE To evaluate the feasibility of aneurysm embolization by using detachable coils under IVUS guidance. METHODS IVUS-guided embolization in conjunction with fluoroscopic imaging and subsequently alone were performed in a silicone model with a side wall aneurysm. IVUS-guided embolization in conjunction with fluoroscopic imaging was also used in an in vitro model of a side wall aneurysm created using sheep vessels. The visibility of the aneurysm, microcatheter, and coils ascertained by the IVUS was graded as excellent, good, or poor based on visualization of these items as distinct structures. The agreement between simultaneously acquired angiographic and IVUS images for detecting increasing intra-aneurysmal coil mass and coil prolapse was assessed in 10 and 6 simultaneously acquired angiographic and IVUS images, respectively. RESULTS IVUS measurements of the aneurysm dimensions strongly correlated with standardized dimensions and measurements acquired by contrast angiography (Pearson coefficient of 0.96 and 0.99 for silicone model and arterial segment model, respectively). IVUS visualization of the aneurysm, microcatheter tip, and coil loops were graded as excellent in the silicone aneurysm model and good in the carotid artery model. The agreement between simultaneously acquired angiographic and IVUS images was very high for detecting increasing intra-aneurysmal coil mass (Spearman rank correlation coefficient of 0.98) and coil prolapse (83% agreement). CONCLUSION IVUS guidance during aneurysm embolization may improve the procedure by providing intravascular aneurysmal measurements and visualization of devices used in the procedure.


Journal of Vascular Surgery | 2012

Feasibility and validation of spinal cord vasculature imaging using high resolution ultrasound

Foad Abd Allah; Shahram Majidi; Masaki Watanabe; Saqib A Chaudhry; Adnan I. Qureshi

BACKGROUND A noninvasive method of visualization of the anterior spinal artery such as ultrasound that can be utilized in emergent or intraoperative settings can reduce the risk of spinal cord ischemia. OBJECTIVE We assessed the feasibility of imaging and characterizing blood flow in the anterior spinal artery using ultrasound with concurrent validation using a cadaveric model. METHODS We developed a protocol for ultrasonographic assessment of anterior spinal artery based on anatomic, morphologic, and physiologic characteristics of anterior spinal artery and determined the feasibility in 24 healthy research participants using high frequency probe (3-9 MHz) through the left lateral paramedian approach in the area between T8 and T12. We ascertained the detection rate, depth of insonation, and flow parameters, including peak systolic velocity, end diastolic velocity, and resistivity indexes for both segmental arteries and anterior spinal artery within the field of insonation. We validated the anatomical landmarks using simultaneous spinal angiography and simulated anterior spinal artery flow in a cadaveric set-up. RESULTS We detected flow in all segmental arteries at different levels of our field of insonation with mean depth (± standard deviation) of insonation at 3.9 ± 0.7 cm identified by characteristic high resistance flow pattern. Anterior spinal artery was detected in 15 (62.5%) research participants at mean depth (± standard deviation) of 6.4 ± 1.2 cm identified by characteristic low resistance bidirectional flow. Age, gender, and body mass index were not correlated with either the detection rate or depth of insonation for anterior spinal artery. Simultaneous spinal angiography and simulated anterior spinal artery flow in a cadaveric set-up confirmed the validity of the anatomic landmarks by demonstrating concordance with results obtained from volunteer research participants. CONCLUSIONS The current study describes a technique for noninvasive imaging of spinal vasculature using ultrasound which may enhance our diagnostic capabilities in emergent and intraoperative settings.


Journal of Ultrasound in Medicine | 2012

Chronologic echogenicity changes and histologic correlates in experimental blood clots a serial sonographic study

Masaki Watanabe; Shahram Majidi; Saqib A Chaudhry; Adnan I. Qureshi

—We performed this study to identify echogenicity changes in clots and their correlations with histologic characteristics over time.


Archive | 2018

Blood Pressure Management in ICH

Shahram Majidi; Adnan I. Qureshi

Elevated systolic blood pressure is very common in patients with acute intracerebral hemorrhage, and it is a well-recognized risk factor for hematoma expansion, neurological deterioration, and poor clinical outcome in these patients. Multiple clinical trials have indicated the safety of acute blood pressure lowering in patients with ICH. However, ATACH II and INTERACT II clinical trials both failed to demonstrate significant improvement in clinical outcome in patients with acute hypertensive intracerebral hemorrhage following intensive blood pressure reduction defined as systolic blood pressure less than 140 mmHg in comparison to standard systolic blood pressure reduction to less than 180 mmHg. It is important to emphasize that the safety and efficacy of intensive blood pressure lowering in patients with unfavorable characteristics such as hematoma volume greater than 30 ml, midline shift, and increased intracranial pressure and patients with lower GCS score remain unclear as overwhelming majority of patients in ATACH II and INTERACT II trials had favorable baseline clinical characteristics. In summary, based on current data and until future trials provide further evidence on safety and efficacy of intensive blood pressure reduction in more specific and individualized subgroups of patients, systolic blood pressure lowering to 140–160 mmHg seems a reasonable blood pressure goal for patients with acute intracerebral hemorrhage.

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Gustavo J. Rodriguez

Texas Tech University Health Sciences Center

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Malik M Adil

University of Minnesota

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M. Suri

University of Minnesota

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