Sami Obaid

Mycobacterium bovis spondylodiscitis after intravesical Bacillus Calmette-Guérin therapy.

Background: Intravesical instillations of live-attenuated Bacillus Calmette-Guérin (BCG) are a well-known and effective method for prevention and treatment of bladder carcinoma and carcinoma in situ. Although considered a safe procedure with rare side effects, local and systemic complications may occur. While long bone ostemolyelitis has been well described, very few reports of BCG spondylodiscitis exist in the literature. Case Description: A 67-year-old man developed low back pain, anorexia, and weight loss 11 months after a 6-week course of intravesical BCG instillations for the treatment of bladder carcinoma in situ. Imaging studies revealed L1-L2 spondylodiscitis with epidural and bilateral psoas abscesses. Tissue cultures obtained by percutaneous computed tomography-guided aspiration were positive for Mycobacterium bovis. Despite triple antituberculous therapy (isoniazid, rifampin, and ethambutol), clinical and radiological progression occurred. Therefore, L1 and L2 corpectomies with extensive debridement were performed, followed by 360° anterior-posterior instrumented fusion. After 20 months of follow-up, the patient remains asymptomatic and recurrence-free. Conclusion: Mycobacterium bovis spondylodiscitis is a rare complication of intravesical BCG therapy. Although medical therapy with antituberculous agents is the first-line treatment, surgical decompression, debridement, and stabilization may be necessary in refractory cases.

Minimally invasive removal of a giant extradural lumbar foraminal schwannoma.

Background: Purely extradural lumbar schwannomas are rare lesions. Resection traditionally requires an open laminectomy and ipsilateral complete facectomy. Recent reports have demonstrated safety and efficacy of removal of these tumors using mini-open access devices with expandable retractors. We report a case of a giant L3 schwannoma successfully resected through a minimally invasive approach using the non-expandable Spotlight tubular retrator (Depuy Spine). Case Description: A 77-year-old woman presented with a history of chronic right leg pain, paresthesias and proximal right leg weakness. Magnetic Resonance imaging (MRI) scan revealed a large dumbbell-shaped extradural foraminal lesion at the L3–L4 level with significant extraforaminal extension. The patient underwent a minimally invasive gross total resection (GTR) of the tumor using an 18-mm Spotlight tubular retractor system. Pathology confirmed the lesion to be a benign schwannoma. Postoperatively, the patients symptoms resolved and she was discharged from the hospital on the second postoperative day. Postoperative MRI showed no residual tumor. The patient returned to normal activities after 2 weeks and remained asymptomatic with no neurological deficits at final 6 months follow-up. Conclusion: Giant lumbar extradural schwannomas can be safely and completely resected using minimally invasive surgery without the need for facectomy or subsequent spinal fusion.

A new method using Raman spectroscopy for in vivo targeted brain cancer tissue biopsy

Modern cancer diagnosis requires histological, molecular, and genomic tumor analyses. Tumor sampling is often achieved using a targeted needle biopsy approach. Targeting errors and cancer heterogeneity causing inaccurate sampling are important limitations of this blind technique leading to non-diagnostic or poor quality samples, and the need for repeated biopsies pose elevated patient risk. An optical technology that can analyze the molecular nature of the tissue prior to harvesting could improve cancer targeting and mitigate patient risk. Here we report on the design, development, and validation of an in situ intraoperative, label-free, cancer detection system based on high wavenumber Raman spectroscopy. This optical detection device was engineered into a commercially available biopsy system allowing tumor analysis prior to tissue harvesting without disrupting workflow. Using a dual validation approach we show that high wavenumber Raman spectroscopy can detect human dense cancer with >60% cancer cells in situ during surgery with a sensitivity and specificity of 80% and 90%, respectively. We also demonstrate for the first time the use of this system in a swine brain biopsy model. These studies set the stage for the clinical translation of this optical molecular imaging method for high yield and safe targeted biopsy.

Chronic subdural haematomas in elderly population. Neurosurgical aspects and focus on the single-burr hole technique performed under assisted local anaesthesia

Abstract Objective: Chronic subdural haematomas (CSDH) is a common pathology that usually affects the elderly population. The incidence of CSDH has recently been increasing with the expansion of the aging population. The objective of our study was to evaluate the outcome following surgical drainage of CSDH in elderly patients. Materials and methods: We performed a retrospective analysis of 455 consecutive patients with CSDHs over a 5-year period. Among them, all 121 patients older than 80-year old were included in the study. Clinical status, comorbidities, type of surgical technique and outcome were analyzed. Outcome at last follow-up was measured using the Markwalder grading score and the Glasgow outcome scale. Results: Patients ranged from 80- to 94-year old with a median age of 84 years (range 80–94). Ninety-eight percent of patients were surgically treated by a small burr hole under assisted local anaesthesia. About 69.2% of patients improved post-operatively. The mortality rate was 6.8%. Conclusion: CSDH is a common pathology in the elderly population. Patients with CSDHs often have comorbodities that need to be considered in deciding whether surgical treatment is indicated. When surgery is elected, small craniostomy techniques performed under assisted local anesthesia is safe and should be favored in this frail population.

Using the trans-lamina terminalis route via a pterional approach to resect a retrochiasmatic craniopharyngioma involving the third ventricle

Retrochiasmatic craniopharyngiomas involving the anterior third ventricle are challenging to access. Although the pterional approach is a common route for suprasellar lesions, when the craniopharyngioma extends behind the chiasma into the third ventricle, access is even more difficult, and the lamina terminalis may offer a good working window. The translamina terminalis approach provides direct access to the retrochiasmatic portion of the tumor with minimal brain retraction and no manipulation of the visual nerves. In this video, we emphasize the utility of using the lamina terminalis corridor to resect the retrochiasmatic intraventricular portion of a craniopharyngioma. The video can be found here: https://youtu.be/hrLNC0hDKe4 .

Endoscopic third ventriculostomy for obstructive hydrocephalus due to intraventricular hemorrhage.

BACKGROUND Although endoscopic third ventriculostomy (ETV) is the first-line treatment for obstructive hydrocephalus due to various pathologies, its role in hemorrhage-related obstructive hydrocephalus is poorly defined. We report our experience with ETV for hemorrhage-related obstructive hydrocephalus, demonstrate it feasibility, and discuss potential advantages over more conventional treatment modalities. METHODS We performed a retrospective analysis of 78 consecutive patients who underwent ETV in our institution between January 2003 and January 2011. We identified 17 consecutive patients who underwent ETV for obstructive hydrocephalus related to intraventricular hemorrhage (IVH). RESULTS ETV was performed in 9 men and 8 women (mean age: 58 years; range: 42-79). All patients had IVH (n = 17), either alone (n = 3) or with intracranial hemorrhage (n = 4) or subarachnoid hemorrhage (SAH) (n = 10). Endoscopic clot evacuation was performed in seven cases (41%). External ventricular drain (EVD) was avoided in two patients. 15 patients had external EVD, and EVD wean was performed on average 5 days post-ETV. Two patients died in the early postoperative period (< 1 month) from the initial cerebral insult. For the 15 surviving patients, the average modified Rankin Scale (mRS) at last follow-up (15 months; range: 1-48) was 2.4. Thus most surviving patients were independent (mRS < 3). Of those 15 patients, one died (malignancy) at last follow-up. Twelve patients (80%) were ventriculoperitoneal shunt-free. The three shunt-dependent patients had significant SAH (100%). CONCLUSION ETV with or without endoscopic clot evacuation is feasible for patients with hemorrhage-related obstructive hydrocephalus. Potential advantages include avoiding or reducing duration of EVD placement and preventing ventriculoperitoneal shunt placement. Further large prospective randomized trials are needed to evaluate the safety and efficacy of ETV with or without clot evacuation for IVH-related obstructive hydrocephalus.

Arteriovenous malformation of the pineal gland

Dear Editor, We would like to bring to your readers’ attention a case of an arteriovenous malformation (AVM) of the pineal gland that was confirmed on histopathological examination following successful surgical removal. To our knowledge, a compact nidus located purely within the pineal gland has been reported only twice, without histopathological demonstration [6, 10]. We wish to emphasize the impact that precise identification of a deep central AVM’s location has on its therapeutic management. To our knowledge, this is the first report of a histopathologically proven intraparenchymal pineal AVM. A 50-year-old woman presented with intraventricular hemorrhage and hydrocephalus. Magnetic resonance imaging (MRI) revealed an AVM of the posterior third ventricle fed by both posterolateral choroidal arteries (PLChA) and draining into an ectatic vein of Galen (VG) (Fig. 1a, b). A flow-related aneurysm of the right PLChA was identified as the probable site of rupture and it was embolized. The AVM was then resected through a supracerebellar-infratentorial approach. The postoperative course was uneventful and there was no residual AVM on postoperative angiography. Histopathological examination confirmed that the AVM’s compact nidus was entirely located within the pineal parenchyma (Fig. 1c). Although there is no consensus on the optimal treatment of ruptured deep central AVMs, the precise location of the AVM may guide towards an optimal treatment plan including: observation, surgical removal, stereotactic radiosurgery (SRS), endovascular therapy (EVT), or a combination of these modalities. The key issue in the therapeutic decision process is the risk associated with AVM accessibility. Lower-risk accessible lesions may be treated with surgery, whereas higher-risk lesions are more prone to be treated with SRS or ETV, with or without additional surgery or complementary SRS [1–3, 5–10]. In his classification of deep central AVMs, Yasargil [10] included a pineal AVM case in the group of mesencephalic AVMs. Another case of pineal AVM has since been reported, and it too was considered to belong to the dorsal midbrain group of AVMs [6]. It is important, however, to recognize that AVMs of the pineal gland are distinct from AVMs of the midbrain or other deep central structures (e.g., thalamus). Although surgical resection of pineal gland AVMs can be performed safely, intraparenchymal AVMs located deep in the thalamus or midbrain are expected to harbor greater surgical risk [1–3, 5–10]. Knowledge of the exact location of deep central AVMs is also a major determinant of its surgical approach. Whereas pineal gland AVMs and superior colliculi AVMs are readily accessible through a supracerebellar-infratentorial approach, this route offers less optimal exposure below the level of the superior colliculus [4]. Recognizing the existence of a pineal gland AVM is important; it influences the choice of treatment modality and surgical approach. Intraparenchymal pineal AVMs should be distinguished from AVMs of other deepseated locations (e.g., midbrain) and from the grouping of heterogeneous AVMs that make up so-called pineal region AVMs. A. G. Weil : S. Obaid :N. McLaughlin :M. W. Bojanowski (*) Department of Surgery, Division of Neurosurgery, Centre Hospitalier de l’Universite de Montreal (CHUM), Hôpital Notre-Dame, 1560 rue Sherbrooke Est, Montreal, QC, Canada H2L 4M1 e-mail: michel.bojanowski.chum@ssss.gouv.qc.ca

Minimally invasive costotransversectomy for the resection of large thoracic dumbbell tumors

Abstract Background: Due to their important size and complex localization, the management of thoracic dumbbell tumors is challenging, frequently requiring the need for an anterior approach. Our study aims to first report the feasibility and safety of a single-stage posterior minimally invasive procedure in achieving complete resection of voluminous thoracic dumbbell tumors. Methods: We retrospectively reviewed the medical records of five consecutive patients, who underwent the minimally invasive resection of a type III thoracic dumbbell tumor in our institution between March 2007 and March 2012. There were two men and three women, with a mean age at diagnosis of 57 years (range 41–68 years). After the placement of a non-expandable tubular retractor under fluoroscopic control, a costotransversectomy was achieved. By moving the retractor in all directions, the tumor was largely exposed and resected with the cavitron ultrasonic surgical aspirator. Clinical and radiological monitoring was performed before discharge, at 6 months, 1 year and 2 years. Results: No major intraoperative complication was reported. Gross total resection was achieved in four patients. The mean operative time was 219 mins (range 75–540 mins) and the mean estimated blood loss was 230 ml (range 50–500 ml). No postoperative complication was reported. The mean length of hospital stay was 3.6 days (range 2–6 days) and all patients were discharged home. Histological analysis confirmed the diagnosis of grade 1 schwannoma in four patients and revealed a hemangiopericytoma in one patient. No tumor recurrence was noted with a mean follow up period of 46 months (range 32–54 months). Conclusion: Thoracic dumbbell tumors can be safely and completely resected using a single-stage minimally invasive procedure. The costotransversectomy can be performed through a non-expandable retractor allowing sufficient access to all parts of the tumor.

Iodinated Contrast Encephalopathy

A 39-year-old, left-handed woman with right temporal lobe epilepsy was admitted for an intracarotid sodium amobarbital procedure (Wada test) to establish language and memory representation of each hemisphere and hence determine if she was suitable for a right anterior temporal lobectomy. This procedure involves catheterization of a carotid artery in a first session (and the other in another session) via the femoral artery before amobarbital injection and, therefore, includes an angiogram of the carotid vasculature using a contrast agent. Following left intracarotid injection of iopamidol contrast agent, she manifested a rapid decrease in consciousness and progressive right hemiplegia, requiring intubation and admission to the intensive care unit. Continuous electroencephalogram monitoring showed severe left hemispheric slowing. Initial brain magnetic resonance imaging (MRI) showed left hemispheric edema suggestive of iodinated contrast encephalopathy (Figure 1). Her level of consciousness and motor strength markedly improved within 2 weeks and neuropsychological deficits resolved over the following months. A repeat neuropsychological evaluation 15 months later showed significant improvement of cognitive function, albeit with some mild language deficits and psychomotor slowing. Serial followups over the next 2 years revealed gradual regression of the MRI abnormalities (Figure 2). Iodinated contrast encephalopathy is an uncommon, usually self-limiting and reversible complication after angiography. The mechanism of neurotoxicity is thought to be a temporary disruption of the blood–brain barrier by the iodinated contrast and parenchymal inflammation. The most frequent clinical presentations are transient cortical blindness, seizures, cognitive dysfunctions, and focal neurological deficits including sensorimotor impairments. Although severe and long-lasting in our patient, most reported cases have lasted less than 2 to 3 hours. Risk factors for iodinated contrast encephalopathy include hypertension and renal failure. Common neuroimaging findings are contrast enhancement and oedema of the cortex, which can be found in up to 54% of computed tomography scans performed within 2 hours of the event. Brain MRI scans more frequently reveal a pattern of focal or diffuse cortical T2-weighted

Praxis-induced reflex seizures mainly precipitated by writing due to a parietal focal cortical dysplasia ☆

We report the case of a 23-year-old left-handed woman with medically intractable praxis-induced reflex seizures mainly precipitated by writing. Selective resection of subtle end-of-sulcus cortical dysplasia in the right inferior parietal lobule resulted in freedom from seizures. To the best of our knowledge, this is the first case of praxis-induced reflex seizures mainly precipitated by writing in which a focal lesion was found and treated successfully by surgery.