Hosam Al-Jehani

Superficial Anastomotic Veins : Neurosurgical View Depending on 251 Craniotomies

BACKGROUND Superficial anastomotic veins (SAVs) have been studied extensively but little attention has been paid to clinical studies. The aim of this study is to provide variations in the drainage patterns of SAVs depending on the intraoperative findings. METHODS A total of 251 craniotomies due to intractable temporal lobe epilepsy were performed between 1972 and 1987 at the Montreal Neurological Institute. The courses of the three largest SAVs including the vein of Trolard (VT), vein of Labbe (VL) and superficial Sylvian vein (SSV) were studied. RESULTS All three veins showed variable courses. The most common predominant vein was the combination of the VL + SSV. The VT and VL were frequently coursed at the level of the central vein and middle temporal vein, respectively. On the right hemisphere the SSV was the predominant type while the VL tended to be predominant on the left hemisphere. A combination of VL and SSV was predominant in patients with right and/or left hemispheric dominance. CONCLUSIONS The SAVs showed considerable variation in their courses and it is difficult to define an exact pattern although some courses showed constant directions. Attention should be paid not to damage these veins since in a considerable number of cases a single dominant vein may be responsible for draining a majority of the lateral surface of cerebral hemisphere.

Peripheral Nerve Stimulation for Chronic Neurogenic Pain

Peripheral nerve stimulation (PNS) has been used for the treatment of neuropathic pain for more than 40 years. Recent interest in the utilization of this technique stems from the many modifications of the original procedure and the refinement of the available hardware. This rendered the procedure less traumatic and more effective, and thus more widely accepted as a neuromodulation technique for the treatment of various chronic pain syndromes including post-traumatic and postsurgical neuropathy, occipital neuralgia, and complex regional pain syndromes, and in relatively new indications for neuromodulation, such as migraines and daily headaches, cluster headaches. We present a review of the principle and indications for the use of PNS, and review our single institution experience that comprises 24 peripheral nerve stimulators as well as 8 occipital nerve stimulators over 13 years. We review the protocol of our approach including the surgical nuances for our implantation technique. Collaborative efforts in future research will lead to a growth in our clinical experience with the utilization of PNS and will help in identifying the best candidates for it. This, along with the development and refinement of the available hardware would lead to a more specific patient selection for each modality of treatment, increasing the efficacy and success of the intended treatment.

Fahr's Disease Presenting with Aneurysmal Subarachnoid Hemorrhage

Fahrs disease is a rare disorder of slowly progressive cognitive, psychiatric, and motor decline associated with idiopathic basal ganglia calcification (IBGC) and widespread calcification in the brain and cerebellum. Acute presentation of IBGC is most often as a seizure disorder; however, we present a case of an acute IBCG presentation in which the cause of the deterioration was an aneurysmal subarachnoid hemorrhage.

Functional results of electrical cortical stimulation of the lower sensory strip

The aim of this paper is to provide functional results obtained from electrical cortical stimulation of the lower postcentral gyrus in patients who underwent either lesional or non-lesional epilepsy surgery. Group I (n=393) included those patients with gliosis or normal tissue and Group II (n=107) included patients with space-occupying lesions. For cortical stimulation, a unipolar voltage-controlled electrode was used. The tongue, lip, and hand/finger sequences over the lower postcentral gyrus lateromedially in both groups were in agreement with classic teaching. The presence of structural lesions, such as tumors and dysplasia, did not affect the vertical representation of the body parts on the lower sensory strip. Individual variations, which included mosaicism over the sensory strip, were frequent. Whether the functional variability and mosaicism within the sensory cortex result from a pathological condition or not remains to be elucidated in healthy humans using advanced non-invasive brain mapping techniques.

The case for mini-craniotomy in the management of chronic subdural hematoma.

Dear Editor, We read with great interest the study by Chon et al. entitled “Independent predictors for recurrence of chronic subdural hematoma” (Chon KH, Lee JM, Koh EJ, Choi HY, Acta Neurochir (Wien). 2012 Sep;154(9):1541–8) [1], addressing the identification of independent risk factors for the recurrence of chronic subdural hematomas. They found a recurrence rate of 7 %, 21 %, and 38 % for the homogenous, laminar and separated type, respectively. And, 87 % of this recurrence cohort required a second surgery, 10.9 % a third surgery, and 2 % a 4th surgery. One reason for this observed recurrence of chronic subdural hematoma is failure of rapid brain re-expansion owing to the presence of constricting inner membranes. The author describes three surgical approaches to evacuation of chronic subdural hematomas, namely, twist drill craniostomy, burr hole craniostomy, and craniotomy [4]. One burr hole craniotomy with closed-system drainage was used in this study. This approach offers a partial solution to the pathology since it allows for evacuation of the chronic subdural hematoma but does not address the constricting membranes, given the restricted visualization and access possible through a burr hole. By contrast, when craniotomy is concerned, the usual notion is that of a sizable opening to evacuate the subdural collection and avoid injuring the cortical surface. Although an effective of way of treating chronic subdural hematomas, the concern raised with this type of surgery is the recovery time and wound healing concerns in an elderly population usually suffering multiple medical comorbidities [4]. When addressing these patients with chronic subdural hematomas, especially the separated and multiloculated type, we utilize the concept of a “mini-craniotomy”; a small, lazy-S incision to allow for two burr holes to be placed 5–6 cm apart connected with an air drill to create a rectangular craniotomy flap, rarely reported in the literature [2, 3]. This approach allows for excellent visualization of the inner and outer membranes and the cortical surface. It provides sufficient exposure allowing for separation and thermal coagulation of all subdural membranes. Opening of the inner membrane, in our experience, accelerates brain expansion. Achieving this goal through a burr hole craniotomy is accompanied by greater risk. A second advantage of the “mini-craniotomy” is that allows for copious and wide spread lavage of the subdural space. This allows for correction of the osmotic gradients in the subdural space by eliminating the osmotically active subdural blood from fluid pockets. We believe that the “mini-craniotomy” concept in evacuation of chronic subdural hematomas of the elderly is an effective compromise between the “minimally-invasive” burr hole and the aggressive, large craniotomy. It offers a fast and effective method that is well tolerated with minimal surgical morbidity, reducing the need for repeat surgery. Its utilization and effectiveness can only be compared to existing standard approaches in a prospective randomized multiinstitutional fashion. H. Al-Jehani (*) :K. Petrecca Department of Neurology and Neurosurgery, Montreal Neurological Institute and Hospital, McGill University, c/o Luisa Birri, 3801 University Street Montreal, Room 109, Montreal, QC H3A 2B4, Canada e-mail: hosam.aljehani@gmail.com

Basilar artery aneurysm presenting with hemiparkinsonism

Intracranial cerebral aneurysms usually present with subarachnoid hemorrhage from rupture. Less frequently, they may produce symptoms due to a space occupying effect. We report a case of a basilar artery aneurysm presenting with hemiparkinsonism. A 52 year old, left-handed, otherwise healthy male presented to our movement disorders clinic with a one-year history of progressive left hand tremor andmicrographia. Examination demonstrated rest tremor and rigidity of the left arm with no other focal deficits. Carbidopaelevodopa produced mild improvement in the tremor and rigidity. Computed tomography (CT) and magnetic resonance imaging (MRI) revealed a partially thrombosed aneurysm arising from the basilar apex, projecting into the substance of the midbrain at the level of the substantia nigra, associated with hyperintensity of the surrounding area of the midbrain on T2-weighted images, denoting edema. (Fig. 1) Cerebral angiography confirmed the presence of a 10 8 mm saccular aneurysm of the distal basilar artery, projecting into the left side of themidbrain parenchyma, compressing the substantia nigra, and presumably producing his hemiparkinsonism (Figs. 2).

Determining the critical size of intracranial aneurysm predisposing to subarachnoid hemorrhage in the Saudi population.

Introduction: Aneurysmal subarachnoid hemorrhage (SAH) is a devastating event with a high rate of morbidity and mortality. With the improvement of diagnostic modalities and the adoption of different screening strategies, more aneurysms are being diagnosed prior to rupture. Based on large multi-center trials, size has become the most important determinant of treatment decisions. Unfortunately, these studies did not take into account the regional and racial variations, challenging the generalizability of their results. Material and Methods: We conducted a retrospective analysis on a series of 192 patients harboring 213 aneurysms. Results: The critical finding in our study is that the majority of patients presenting with SAH due to ruptured aneurysms are <10 mm in size. Conclusion: Decision to treatment of a given unruptured intracranial aneurysm should be individually assessed and not taken from general international literature as this may mistakenly apply factors from one population to another.

Is decompressive craniectomy detrimental to the treatment and outcome of severe traumatic brain injury

Dear Editor, Intracranial hypertension is a significant factor contributing to the unfavorable outcomes seen in traumatic brain injury (TBI) [1–4]. Since high ICP can often be attributed to brain edema, and be refractory to medical therapy, decompressive craniectomy (DC) has long been considered a potential therapy to overcome this problem. It could potentially provide the needed extracranial space for the edematous brain to expand. This in turn could protect the vital brain structures from mass effect and improve cerebral autoregulation and cerebral blood flow. However, there is great debate regarding this concept [5–11], mainly due to the lack of a randomized trial until recently. We reviewed with much anticipation the results of a DECRA trial by Cooper et al. on decompressive craniectomy for the treatment of severe traumatic brain injury [12]. However, its methodology suffers from many problems that preclude drawing firm and sound conclusions to justify a major shift in clinical practice.

Scedosporium cerebral abscesses after extra-corporeal membrane oxygenation.

BACKGROUND Scedosporial infections are usually encountered in the immunocompromised patients. However, they are now emerging in the immunocompetent population and have an affinity for the central nervous system. They represent a therapeutic challenge, since they are highly resistant to most antifungal medications. METHODS We report the case of an immunocompetent patient with multiple cerebral abscesses secondary to Scedosporium apiospermum following extracorporeal membrane oxygenation (ECMO) and review the literature about this challenging cerebral infection. RESULTS A previously healthy 33-year-old male admitted to the hospital for a community-acquired pneumonia requiring ECMO subsequently developed multiple cerebral abscesses. He was empirically treated with caspofungin, which was changed to voriconazole once surgical aspiration revealed Scedosporium apiospermum. Despite multiple aspirations, decompressive craniectomy to alleviate intracranial pressure, and an appropriate antifungal agent, the patient did not survive this aggressive infection. CONCLUSION Brain abscesses with Scedosporium apiospermum present a therapeutic challenge. High clinical suspicion leading to early appropriate antifungal therapy and combined surgical interventions might improve the prognosis.

CT Perfusion to Guide Placement of Invasive Cerebral Perfusion Monitor in Subarachnoid Hemorrhage Induced Vasospasm

Background Vasospasm is a challenging component of the subarachnoid hemorrhage “syndrome” that is unpredictable and very difficult to monitor using noninvasive or invasive monitoring technologies in neurocritical units. Methods We describe the novel use of computerized tomography perfusion (CTP) imaging to choose proper targets for invasive cerebral blood flow monitors. Results A total of 3 patients are included in this report. CTP parameters were used to generate points of interest to target using invasive cerebral monitoring of the cerebral blood flow and initiate vasodilator therapy and subsequently guide its weaning. Conclusions CTP can be useful in localizing a specific anatomical target for invasive monitoring in subarachnoid hemorrhage patients suffering from vasospasm.