Tamer Hassan

Tamer Hassan
Alexandria University | AU · Department of Neurosurgery

MD, PhD

About

53
Publications
19,096
Reads
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761
Citations
Additional affiliations
February 2014 - December 2016
Alexandria University
Position
  • Professor
Description
  • Principal investigator of the Research Center of computational Neurovascular Biomechanics
April 2001 - April 2005
Kohnan Hospital
Position
  • doctor student
Description
  • PhD degree and Japan neurosurgical board study
January 1993 - present
Alexandria Faculty of Medicine
Position
  • Professor (Associate)

Publications

Publications (53)
Article
Full-text available
Background and purpose Coronavirus disease 2019 (COVID-19) is associated with a small but clinically significant risk of stroke, the cause of which is frequently cryptogenic. In a large multinational cohort of consecutive COVID-19 patients with stroke, we evaluated clinical predictors of cryptogenic stroke, short-term functional outcomes and in-hos...
Preprint
Full-text available
Background: spontaneous obliteration of cerebral arteriovenous malformations is uncommon but could occur after partial embolization. Materials and methods: A retrospective study of 140 patients that underwent embolization for cerebral AVMs from 2005 to August 2019 using liquid embolic agents. The angiographic outcome of patients was classified as r...
Article
Background and purpose: Coronavirus disease 2019 (COVID-19) is associated with a small but clinically significant risk of stroke, the cause of which is frequently cryptogenic. In a large multinational cohort of consecutive COVID-19 patients with stroke, we evaluated clinical predictors of cryptogenic stroke, short-term functional outcomes and in-ho...
Article
Full-text available
Background: In developing countries like Egypt, the clinical workflow of stroke management is poorly established due to the lack of awareness of the stroke patients concerning their need of therapeutic intervention and the poor identification of facilities equipped to treat stroke. Hence, establishing a stroke system of care in developing countries...
Article
Full-text available
Although endovascular catheter embolization (ECE) has been accepted as a therapeutic option for arteriovenous malformations (AVMs) in children and adolescents, considerable and substantial data are still lacking regarding the outcomes of CE for AVMs. This study aimed to clarify the outcomes and the complications of ECE for the treatment of AVM in p...
Article
Full-text available
Background and purpose Coronavirus disease 2019 (COVID-19) is associated with a small but clinically significant risk of stroke, the cause of which is frequently cryptogenic. In a large multinational cohort of consecutive COVID-19 patients with stroke, we evaluated clinical predictors of cryptogenic stroke, short-term functional outcomes and in-hos...
Article
Full-text available
Background purpose: Vein of Galen aneurysmal malformations (VGAM) may carry life-threatening and catastrophic sequelae in children. Their clinical presentations are differently variable between cardiac and cerebral syndromes. There may be a possible relationship between the Galenic angioarchitecture and the clinical presentation. We aimed to study...
Article
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Background and Objectives: Its well known that the COVID-19 is disease causes a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), less known that the COVID-19 can attach the brain through the olfactory nerve in the nasal cavity and damage neurons that control breathing of central nervous system (CNS). The aim of this study is to underst...
Article
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Despite the plethora of published studies on intracranial aneurysms (IAs) hemodynamic using computational fluid dynamics (CFD), limited progress has been made towards understanding the complex physics and biology underlying IA pathophysiology. Guided by 1733 published papers, we review and discuss the contemporary IA hemodynamics paradigm establish...
Article
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Computational fluid dynamics (CFD) studies of intracranial hemodynamics often use Newtonian viscosity model to close the shear rate term in the Navier-Stokes equation. This is based on a commonly accepted hypothesis which state that non-Newtonian effects can be neglected in intracranial blood flow. This study aims to examine the validity of such hy...
Conference Paper
Full-text available
The formation and growth of cerebral aneurysm (CA) involves numerous complex biological, biochemical and mechanobiological processes. Vascular endothelium is largely affected by hemodynamics. The response of endothelial cells (EC) to shear stress has been identified as the prime initiator of CA formation and growth. This paper presents a critical o...
Article
Background and objectives: The present study is focused on correlation of parent vessels and Neck diameters with Acoma aneurysmal depth and growth direction. The study principally aims to suggest new classification of Acoma-located aneurysms based on physical characteristics of parent vessels. Methods: Retrospective analysis of 155 patients with...
Article
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Background: spinal cord arterio-venous fistulas are rare cause of progressive myelopathy. The predictive factors of their outcome after endovascular or surgical treatment are still controversial. Materials and methods: Twenty patients were diagnosed with spinal arterio-venous fistulas; 13 of them had dural and 7 had perimedullary fistulas (1 Dor...
Article
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Background Data: Open lumbar microdiscectomy has been considered the gold standard in the management of lumbar disc herniation (LDH) because of its favorable outcomes in long-term follow up. Nowadays, minimally invasive discectomy is gaining recognition due to its advantages. The advantages endoscopic lumbar discectomy includes clear visualization,...
Article
Background: Solid cerebellar hemangioblastomas are highly vascular lesions and may cause catastrophic hemorrhage during excision. Methods: This retrospective study enrolled 10 patients (7 men and 3 women, with a mean age of 38.2 ± 12.5 years) with solid cerebellar hemangioblastomas. All patients had a solitary tumor and underwent surgical resect...
Article
Full-text available
Background Cavernous sinus (CS) fistulas are classified into traumatic and spontaneous. Traumatic carotid–cavernous fistulas (CCFs) are usually direct internal carotid artery (ICA) high-flow fistulas; whereas spontaneous CCFs are usually dural, low-flow fistulas and generally possess less severe symptoms than direct carotid–cavernous fistulas. Met...
Conference Paper
Full-text available
NTRODUCTION - OBJECTIVE:The management of basilar artery fenestration aneurysms (BAFAs) is challenging due to their location and difficult configuration. METHOD:Retrospective study of patients with BAFAs from May 2006 to March 2012 was done. We encountered 8 patients with 11 aneurysms. The mean age was 61.5 ± 14.3 (mean ± SD). 3 were presented with...
Conference Paper
Full-text available
Blood hemodynamics studies is becoming a significant tool for facilitating diagnosis and rupture risk assessment of cerebral aneurysms. The purpose of this study is to present a comparative study between Newtonian and non-Newtonian blood viscosity models for simulating the hemodynamic wall shear stress (WSS) of cerebral aneurysms. The non-Newtonian...
Article
Full-text available
Introduction: Spinal cord arteriovenous malformations and fistulae are rare vascular lesions than can lead to myelopathy that is at many instances overlooked during diagnosing the cause of progressive myelopathy and weakness. Treatment options involve either endovascular embolization, surgical disconnection or a combination of both. This study aim...
Article
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Background and Importance: Aneurysm formation after superficial temporal artery (STA)-middle cerebral artery (MCA) bypass is a rare condition with only a handful of cases reported in the literature with various presentations and management strategies. Various theories have been postulated to explain such rare complication and to determine whether i...
Article
Full-text available
Spontaneous pure acute bilateral subdural haematoma (ASDH) without intraparenchymal or subarachnoid haemorrhage caused bya ruptured cerebral aneurysm is extremely rare. It can follow rupture of different aneurysms specially located in anterior incisural space; the most frequently encountered location is the PcoA aneurysms as demonstrated in the pre...
Article
Full-text available
Giant intracranial aneurysms are rare disorders that represent only 5 % of all intracranial aneurysms; they have a wide variety of presentations including rupture, embolic effects, and mass effect symptoms that can mislead the diagnosis to tumors rather than aneurysms. Their treatment is difficult and carries higher morbidity and mortality than usu...
Article
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Background: Traumatic carotid pseudoaneurysms are a rare cause of intractable recurrent epistaxis following a head trauma that is usually treated after a delay by days or even months. Their management includes various options, surgical or endo-vascular, depending on the clinical situation and the angio-graphic findings in the patient, with a prefer...
Article
Background: Functional evaluation of the feeder vessels of the arteriovenous malformations (AVMs) through the super-se-lective cerebral angiography route reveals which tolerable and intolerable arteries are safe for embolization. Propofol is an-other agent, in place of amobarbital, for the provocative test. The purpose of this study was to show our...
Article
Background: Vein of Galen aneurysmal malformations are a rare entity of vascular malformations that present themselves in neonates and infants by congestive heart failure in early days of life or later on by hydrocephalus and macrocephaly; very few reports exist on their presentation in adulthood. Case Presentation: In this case report, we review a...
Article
Full-text available
Background: Traumatic carotid pseudoaneurysms are a rare cause of intractable recurrent epistaxis following a head trauma that is usually treated after a delay by days or even months. Their management includes various options, surgical or endo-vascular, depending on the clinical situation and the angio-graphic findings in the patient, with a prefer...
Article
BACKGROUND: Embolization is a safe curative tool in low-grade arteriovenous malformations (AVMs). N-butyl cyanoacrylate (NBCA) and Onyx are comparable to each other depending on the lesion characteristics. METHODS: Starting in 2003, 70 patients (31 males, 39 females; mean age, 29.7 y; range, 7 to 72 y) with intracranial AVMs were embolized with NBC...
Article
Full-text available
Aneurysms presented with mass effect are traditionally treated by surgical clipping to decompress their mass effect. The aim of this work is to discuss the efficiency of endovascular techniques in treating 47 patients with variable sizes of intracranial aneurysms presented with mass effect and/or cranial nerve palsy. There were 47 patients with 47...
Article
Full-text available
OBJECTIVE:: Unlike intraventricular hemorrhage (IVH) occurring in neonates, the natural history of IVH in adults is yet to be clarified. Restoration of patency of the ventricular pathway and avoidance of development of hydrocephalus are the main goals in therapy of IVH. The aim of this study was to assess the natural history, presentations, and evo...
Article
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Magnesium, one of the essential trace elements, plays important roles in maintaining both normal cellular and body functions. S100 calcium-binding protein B (S100B) has been used as a marker of glial damage in several neurological disorders. Thirty patients with ruptured intracranial aneurysms treated by clipping are included. The patients were ran...
Article
Objective: To present our experience in balloon test occlusion (BTO) for giant carotid aneurysms under hypotensive challenge and neuroleptic analgesia. Methods: Twenty-five patients with giant carotid aneurysms underwent BTO. Only patients who showed absence of any neurological deficits for 20 minutes under normal blood pressure repeated the test f...
Article
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We describe our experience in balloon test occlusion for giant carotid or basilar aneurysms under hypotension. Twenty-four patients underwent balloon test occlusion (BTO) during the year 2008. Only patients showed absence of any neurological deficits after 20 minutes under normal tension then another 20 minutes under hypotension were considered tol...
Article
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Objective: Hypertensive intracerebral hematoma is a neurosurgical emergency that has a high mortality and morbidity. Common locations include putaminal, thalamic, cerebellar, and pontine. The aim of this study is to identify easily applicable guidelines for surgical and nonsurgical treatment. Methods: Seventy-seven cases with hypertensive intracere...
Article
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Stent deployment across the aneurysmal neck has been established as one of the endovascular methods to treat intracranial aneurysms with or without coils. The purpose is to study the possible adverse effects of deployment of the new flow-diverter stent-like devices (FD) on the flow characteristics of saccular aneurysm models. Numerical simulations...
Article
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Parent vessel plays an important role in aneurysm formation and rupture. The diameter of either the A1 arteries is the peculiar key controlling the flow of the anterior communicating artery (ACOMA) aneurysms (ANs). The purpose is to study the effect of parent vessel dominancy, that is, the diameter of the A1 artery, on the flow characteristics of t...
Article
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We present our experience with managing 13 cases of vein of Galen aneurysm with a special focus on endovascular strategies. This clinical review deals with the multivariable clinical presentation of vein of Galen aneurysms and the role of transarterial endovascular treatment. Thirteen patients diagnosed with vein of Galen aneurysms have been review...
Article
Full-text available
The authors created a simple, broadly applicable classification of saccular intracranial aneurysms into three categories: sidewall (SW), sidewall with branching vessel (SWBV), and endwall (EW) according to the angiographically documented patterns of their parent arteries. Using computational flow dynamics analysis (CFDA) of simple models representi...
Article
The authors report their experience in endovascular treatment of basilar artery (BA) trunk aneurysms by intra-aneurysmal and BA occlusion. Four patients were referred to our hospital from 1995 until 2002 with variable clinical presentations and radiologic appearances. All the patients were subjected for tolerability to balloon BA occlusion test to...
Article
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We present a relatively simple approach that physicians can use to reconstruct cerebral vessels as 3D numerical grids or computational replicas. The method accurately duplicates their geometry to provide computer simulations of their blood flow. Initial images were obtained by using any medical imaging technique, such as MR angiography, CT angiogra...
Article
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We applied computational fluid dynamics (CFD) analysis to assess 3D digital subtraction angiography findings in a patient with a giant vertebrobasilar aneurysm to simulate and compare the consequences of left and right vertebral artery occlusion. The balloon occlusion test suggested that occlusion of the right vertebral artery is the better way to...
Article
Cervical myelopathy induced by vascular compression is rare. We report a case caused by bilateral persistence of the first intersegmental arteries (a vertebral artery anomaly). Myelopathy was successfully treated with vascular decompression. A 66-year-old woman presented with gradually worsening paroxysmal neck and arm pain. Magnetic resonance imag...
Article
Full-text available
We applied computational fluid dynamic (CFD) analysis on the numerical grid of a 3D rotational digital subtraction angiogram obtained in a 22-year-old male patient, with an accidentally discovered vein of Galen malformation associated with single feeder aneurysm, to understand the flow pattern through the two aneurysms and improve our general under...
Article
Full-text available
An unusual case of prolactin-producing adenoma with extensive amyloid deposition is reported to clarify its radiological, intraoperative, and light- and electron-microscopic findings. A 41-year-old female patient complained of amenorrhea persisting for 20 years. Magnetic resonance imaging (MRI) revealed a pituitary adenoma, which included low-inten...

Projects

Projects (5)
Project
Increasing the research activities from MENA+ region in the field of Cerebrovascular disorders and Neuro-intervention to reveal different aspects of our region extending from west to far west across more than 17 countries with about 1 billion population capacity.