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Dive into the research topics where Yahia Z. Al-Tamimi is active.

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Featured researches published by Yahia Z. Al-Tamimi.


World Neurosurgery | 2010

A Review of Delayed Ischemic Neurologic Deficit Following Aneurysmal Subarachnoid Hemorrhage: Historical Overview, Current Treatment, and Pathophysiology

Yahia Z. Al-Tamimi; Nicolas M. Orsi; Audrey Quinn; Shervanthi Homer-Vanniasinkam; Stuart Ross

Delayed ischemic neurologic deficit (DIND) is a serious and poorly understood complication of aneurysmal subarachnoid hemorrhage. Although advances in treatment have improved prognosis for these patients, long-term clinical outcomes remain disappointing. Historically, angiographic vasospasm was thought to result in a DIND, although an increasing body of evidence suggests that this is an oversimplification, because interventions that have effectively targeted angiographic vasospasm have not improved outcome. Consequently, the relationship between angiographic vasospasm and neurologic outcome may be associative rather than causative. Although our understanding of the underlying molecular processes and pathophysiology is improving, responsible mediators or pathways have yet to be identified. The aim of this review is to summarize the key historical events that have helped shape our understanding of the pathophysiology of this phenomenon (microcirculation, autoregulation, microthrombosis, inflammation, apoptosis, spreading depolarization, oxidative stress) and to present the evidence underlying current treatment strategies (hemodynamic therapy, oral nimodipine, endovascular therapy, statins, cerebrospinal fluid drainage, thrombolysis, magnesium) and the translational and clinical research investigating DIND.


Stroke | 2012

Lumbar Drainage of Cerebrospinal Fluid After Aneurysmal Subarachnoid Hemorrhage: A Prospective, Randomized, Controlled Trial (LUMAS)

Yahia Z. Al-Tamimi; Deepti Bhargava; Richard G. Feltbower; Gregory Hall; Anthony Goddard; Audrey Quinn; Stuart Ross

Background and Purpose— A single-center prospective randomized controlled trial has been conducted to determine if lumbar drainage of cerebrospinal fluid after aneurysmal subarachnoid hemorrhage reduces the prevalence of delayed ischemic neurological deficit and improves clinical outcome. Methods— Patients with World Federation of Neurological Surgeons Grade 1 to 3 aneurysmal subarachnoid hemorrhage and modified Fisher Grades 2, 3, 4, and 3+4 were randomized to either the study group of standard therapy plus insertion of a lumbar drain or the control group of standard therapy alone. The primary outcome measure was the prevalence of delayed ischemic neurological deficit. Results— Two hundred ten patients with aneurysmal subarachnoid hemorrhage (166 female, 44 male; median age, 54 years; interquartile range, 45–62 years) were recruited into the control (n=105) and study (n=105) groups of the trial. World Federation of Neurological Surgeons grade was: 1 (n=139), 2 (n=60), and 3 (n=11); Fisher grade was: 2 (n=87), 3 (n=85), and 4 (n=38). The prevalence of delayed ischemic neurological deficit was 35.2% and 21.0% in the control and study groups, respectively (P=0.021). The prevalence of a modified Rankin Scale score of 4, 5, or 6 at Day 10 and 6 months, respectively, was 62.5% and 18.6% in the control group and 44.8% and 19.8% in the study group (P=0.009 and 0.83, respectively). Conclusions— Lumbar drainage of cerebrospinal fluid after aneurysmal subarachnoid hemorrhage has been shown to reduce the prevalence of delayed ischemic neurological deficit and improve early clinical outcome but failed to improve outcome at 6 months after aneurysmal subarachnoid hemorrhage. Clinical Trial Registration— URL: www.clinicaltrials.gov. Unique identifier: NCT00842049.


British Journal of Neurosurgery | 2012

Comparison of acrylic and titanium cranioplasty

Yahia Z. Al-Tamimi; Priyank Sinha; Mili Trivedi; Craig Robson; Tamara A. Al-Musawi; Naveed Hossain; Christopher Mumford; Gerry Towns

Introduction. There are many indications for cranioplasty with an increasing incidence partly attributable to an increase in decompressive craniectomy following trauma and stroke. The aim of this study was to compare the survival of acrylic and titanium cranioplasties used in our department. Materials and methods. Retrospective cohort study of 126 patients who underwent cranioplasty between 1997 and 2007. A comparison was made between those with acrylic (n = 61) and titanium (n = 65) cranioplasties. There was no significant difference in age and length of time between craniectomy and cranioplasty between the two groups. The indications for titanium cranioplasty tended to be classified as ‘high risk’ indications including trauma and stroke. A higher rate of pre-existing infection was noted in the acrylic group. Mean follow-up was 97.2 and 34 months for acrylic and titanium cranioplasties respectively. Results. Mean survival (95% confidence intervals) was 135 months (134–153) and 92 months (82–102) for acrylic and cranioplasty respectively. Out of 13 failures, only two were associated with pre-existing infection. Overall cumulative survival was better for acrylic cranioplasty although this difference did not reach statistical significance. Discussion. Although survival of acrylic cranioplasty appears to be better than titanium plates, there is no statistical significance. Acrylic has the advantage of being able to be applied at the time of surgery without any planning and does not cause artefact on future imaging. Titanium cranioplasty is strong, light-weight and inert and can be fashioned in the pre-operative setting.


Journal of Neurosurgery | 2008

Patients with autosomal-recessive osteopetrosis presenting with hydrocephalus and hindbrain posterior fossa crowding.

Yahia Z. Al-Tamimi; Atul Tyagi; Paul Chumas; Darach Crimmins

Osteopetrosis is a heterogeneous group of disorders characterized by abnormal bone sclerosis. As a result, patients often require input regarding various neurological complications. Although autosomal-recessive osteopetrosis has been associated with hydrocephalus, it has not been linked to hindbrain abnormalities. The authors present 3 cases of auto-somal-recessive osteopetrosis in patients who presented with hydrocephalus. In each of these patients, cerebrospinal fluid diversion procedures were required and hindbrain compression developed. To date, only 1 patient has needed craniocervical decompression due to symptomatic brainstem compression.


BMJ Open | 2014

Self-perceived health status following aneurysmal subarachnoid haemorrhage: a cohort study.

Audrey Quinn; Deepti Bhargava; Yahia Z. Al-Tamimi; Matthew J Clark; Stuart Ross; Alan Tennant

Objective The objective of the study was to assess the long-term self-reported health status and quality of life (QoL) of patients following an aneurysmal subarachnoid haemorrhage (ASAH) using a self-completed questionnaire booklet. Design A two-cohort study. Setting A regional tertiary neurosurgical centre. Participants 2 cohorts of patients with ASAH treated between 1998 and 2008 and followed up at approximately 1 year. Interventions Routine care. Primary and secondary outcomes A range of standardised scales included: AKC Short Sentences Test, the Barthel Index, the Self-Report Dysexecutive Questionnaire, the Everyday Memory Questionnaire, Stroke Symptom Checklist, Wimbledon Self-Report Scale, Modified Rankin Score (MRS) and a new Stroke-QoL. The data from summated scales were fit to the Rasch measurement model to validate the summed score. Results 214 patients (48%) returned the questionnaires; the majority (76%) had a World Federation of Neurosurgeons grade of 1 or 2. The most frequent aneurysm type was that of the anterior communicating artery (28%) with approximately 90% of aneurysms of the anterior circulation. Of those previously in full or part-time employment, 48.9% were unemployed at follow-up. All summated scales satisfied the Rasch measurement model requirements, such that their summed scores were a sufficient statistic. Given this, one-third of patients were noted to have a significant mood disorder and 25% had significant dysexecutive function. Patients with an MRS of 3, 4 or 5 had significantly worse scores on most outcome measures, but a significant minority of those with a score of zero had failed to return to work and displayed significant mood disorder. Conclusions A range of self-reported cognitive and physical deficits have been highlighted in a cohort of patients with ASAH. While the MRS has been shown to provide a reasonable indication of outcome, in routine clinical follow-up it requires supplementation by instruments assessing dysexecutive function, memory and mood.


British Journal of Neurosurgery | 2013

Occurrence and distribution of pilomyxoid astrocytoma

Deepti Bhargava; Priyank Sinha; Paul Chumas; Yahia Z. Al-Tamimi; A. Shivane; Aruna Chakrabarty; Surash Surash; F. Novegno; Darach Crimmins; Atul Tyagi

Abstract Purpose. To know the occurrence and distribution of Pilomyxoid Astrocytomas amongst tumours previously diagnosed histologically as Pilocytic Astrocytoma and to assess the clinical impact of this new entity. Methods. Retrospective Diagnostic review of all cases histologically diagnosed as WHO Grade I Astrocytoma at a single Neurosurgical unit between 1990 and 2003. Results. Of a total of 91 cases identified, 9 were found to have Pilomyxoid histology. Of these, 8 were children (mean age 3.33 years) and 1 adult. 6 tumours were hypothalamochiasmatic in location. The clinical course of Pilomyxoid tumours was aggressive marked by maturation, multiple recurrences and disease control was rarely achieved with single treatment modality as opposed to typical pilocytics. The overall survival of the pilomyxoid group was not statistically different from the pilocytic tumours. Conclusions. Encompassing all age-groups and locations, Pilomyxoid Astrocytomas constitute about 10% of all tumours previously diagnosed as Pilocytic Astrocytoma. Nearly two-thirds are hypothalamo-chiasmatic in location. Knowledge of this entity is essential for appropriate aggressive treatment and follow-up.


Journal of Clinical Neuroscience | 2010

A comparison of the outcome of aneurysmal subarachnoid haemorrhage before and after the introduction of an endovascular service

Yahia Z. Al-Tamimi; Maleeha Ahmad; Sophie E. May; Mohammed H. Bholah; Jacqueline Callear; Anthony Goddard; Audrey Quinn; Stuart Ross

There has been a rapid change from predominantly surgical to endovascular treatment of ruptured intracranial aneurysms giving the opportunity to assess change in patient outcome during this transition. We identified and followed 139 patients with subarachnoid haemorrhage (SAH) treated in the year prior to (group 1) and following (group 2) the introduction of an endovascular service in a retrospective, cross-sectional study. A total of 78.7% of patients in group 1 underwent surgical treatment, 10.7% underwent endovascular treatment and 10.7% received no treatment, whereas patients in group 2 received 29.7%, 65.7% and 4.7%, respectively. MRS scores were obtained in 91% of patients in group 1 and in 89% of patients in group 2. A total of 30.7% and 24.0% of patients had a poor outcome in groups 1 and 2 respectively (p=0.34). The overall change in the management of ruptured cerebral aneurysms in the post-International Subarachnoid Aneurysm Trial (ISAT) era has not significantly changed cross-sectional outcome, although absolute differences appear to reflect difference in outcome noted in the ISAT.


British Journal of Neurosurgery | 2011

The Isadora syndrome: A case report of cervical, oesophageal and tracheal transection in a go-karting accident

Maleeha Ahmad; Priyank Sinha; Yahia Z. Al-Tamimi; Deborah Sylvester; Atilla Dezso; Jake Timothy

We report a case of cervical spine, tracheal and oesophageal trauma from a go-karting injury caused by the patients scarf catching in the vehicles wheel. We discuss the significance of the pre-hospital and operative management of this potentially life-threatening injury by a multi-specialty surgical team. The importance of health and safety issues in recreational sports is highlighted in view of the increasing incidence of cervical spine trauma over past two decades.


Acta neurochirurgica | 2011

New Modalities to Assess Efficacy of Triple-H Therapy: Early Experience

Deepti Bhargava; Yahia Z. Al-Tamimi; Audrey Quinn; Stuart Ross

The traditional axiom that vasospasm induced reduction of blood flow leads to poor tissue oxygenation and ischaemic cellular injury culminating in delayed neurological deficits has been challenged and the efficacy of triple H therapy in reversal of the above is debated. In this study we assess cerebral physiology before and during onset of DIND and with application of triple H therapy with real time neuro-monitoring tools. Patients with Fisher grade 3/4/3 + 4/rebleed were consented. Probes for measuring rCBF, pTiO2, and Microdialysis parameters - glucose, glycerol, lactate, and pyruvate were inserted at time of coiling/clipping. Subsequent monitoring was done in HDU/ITU setting. Return of parameters to baseline was regarded as effective triple H therapy. Study is ongoing and the current paper presents our experience with first five patients. The results suggest safety and feasibility of multimodal monitoring in clinical setting to establish an understanding of relationship between clinical symptoms, brain perfusion, oxygenation, and metabolism in real time to test and guide therapy in future.


World Neurosurgery | 2017

Low-Grade Glioma with Foci of Early Transformation Does Not Necessarily Require Adjuvant Therapy After Radical Surgical Resection

Yahia Z. Al-Tamimi; Martin S. Palin; Tufail Patankar; Jeremy Macmullen-Price; Daniel O'Hara; Carmel Loughrey; Aruna Chakrabarty; Azzam Ismail; Paul Roberts; Hugues Duffau; Paul Chumas

BACKGROUND Low-grade glioma (LGG) is a slow-growing tumor often found in young adults with minimal or no symptoms. As opposed to true low-grade lesions such as dysembryoplastic neuroepithelial tumors, they are associated with continuous growth and inevitable malignant transformation. METHODS Case series of patients who have had en bloc resection of LGG with foci of anaplasia found embedded within the tumor specimen and not at margins. Patients were offered and agreed to a conservative approach avoiding adjuvant therapy. RESULTS In the current case series, we describe a small subset of LGG that have shown foci of high-grade glioma but have shown behavior and growth tendencies similar to LGG after radical surgical resection. No patient to date has shown recurrent disease requiring adjuvant therapy. CONCLUSIONS This case series supports the use of early aggressive surgical treatment of grade II gliomas that are premalignant. It acts as proof of concept that after radical resection, the presence of small foci of transformation embedded within grade II tumor may be treated with close radiologic surveillance rather than immediate adjuvant therapy.

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Paul Chumas

Leeds General Infirmary

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Audrey Quinn

Leeds General Infirmary

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Stuart Ross

Leeds General Infirmary

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Atul Tyagi

Leeds General Infirmary

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Hugues Duffau

University of Montpellier

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