Ramesh Sahjpaul - Academia.edu (original) (raw)

Papers by Ramesh Sahjpaul

$Research paper thumbnail of PO214 / #734 Outcomes of Spinal Cord Stimulation for Refractory Angina$

Neuromodulation: Technology at the Neural Interface

Ophthalmic Surgery, Lasers and Imaging Retina, 1996

A rare presentation of intraorbital Hodgkin's lymphoma in a patient without prior history... more A rare presentation of intraorbital Hodgkin's lymphoma in a patient without prior history of systemic disease who complained of episodic monocular visual loss with minimal proptosis is reviewed. The case is further distinguished by intracranial extension of the tumor. A literature review highlights such an unusual event against the background of prior experience. Despite the fact Hodgkin's disease accounts for about 30% of systemic lymphomas, it rarely occurs in the orbit, where non-Hodgkin's lymphomas account for practically all lymphomas studied. Hodgkin's disease has occurred in patients with known systemic disease in its terminal stages and usually with proptosis as the presenting symptom. We present the case of a young man with intraorbital Hodgkin's disease whose presenting symptom was recurrent transient episodes of complete monocular visual loss. His condition was further distinguished by seeding of the skull base and dura by tumor.

The Canadian journal of neurological sciences. Le journal canadien des sciences neurologiques, Jul 11, 2018

Seminars in Neurosurgery, 2002

Manifestation of congenital anomalies of cranio-vertebral junction (CVJ) in the later half of lif... more Manifestation of congenital anomalies of cranio-vertebral junction (CVJ) in the later half of life is unusual and intriguing. Coexisting cervical spondylotic changes with multilevel compression, poorer bone quality as well as less smooth post-surgical recuperation make management of elderly Congenital Atlantoaxial Dislocation/ Basilar Invagination (CAAD/BI) challenging. The clinico-radiological presentation, pathogenesis and outcome are analysed here. radiological evaluation is required in those with additional subaxial compression. Bone quality in elderly is not a deterrent for instrumentation. Fusion eventually occurs in most.

Journal of Neurosurgery Spine, 2008

The Canadian Journal of Neurological Sciences, 2004

Background:Calcium pyrophosphate dihydrate deposition in the cervical spine is infrequently sympt... more Background:Calcium pyrophosphate dihydrate deposition in the cervical spine is infrequently symptomatic. This is especially true at the craniocervical junction and upper cervical spine.Case Report:A 70-year-old previously healthy woman presented with a progressive cervical myelopathy of four months duration.Results:Examination revealed sensorimotor findings consistent with an upper cervical myelopathy. Radiological studies (plain radiographs, computed tomography, and magnetic resonance imaging) revealed C1-2 instability, and a well-defined extradural 3cm x 1cm retro-odontoid mass causing spinal cord compression. Transoral resection of the mass was performed followed by posterior C1-2 stabilization. Histological examination of the mass confirmed calcium pyrophosphate dihydrate deposition. Follow-up examination showed marked clinical and radiological improvement.Conclusion:Although uncommon, calcium pyrophosphate dihydrate deposition disease should be considered in the differential di...

Healthcare Quarterly, 2014

If you were to have an operation tomorrow, would you want your surgical team members to feel comf... more If you were to have an operation tomorrow, would you want your surgical team members to feel comfortable speaking up, to defy hierarchy, to interact with each other just as well as they perform technical aspects of the procedure? Would you want to feel like part of the team? Your answers to these admittedly leading questions are based on the culture of the surgical team and the interdependence of team members and are at the heart of a current debate around the surgical checklist's effectiveness. In British Columbia (BC), many individuals responded to the paper by Urbach et al. (2014) that described the minimal impact on patient mortality after implementation of the surgical safety checklist in Ontario. They wrote to the Surgical Quality Action Network (SQAN) to express their perspectives, and interestingly, some refuted and others supported the conclusions. Given the strong reaction this study created in the surgical community, a number of key stakeholders have prepared a response in order to provide another perspective to the article and emphasize the checklist's value for improving the culture of surgical teams.

The Canadian Journal of Neurological Sciences, 2002

Background:The observation of an intraluminal common carotid artery thrombus overlying a wall def... more Background:The observation of an intraluminal common carotid artery thrombus overlying a wall defect at ultrasonography or angiography is unusual. To our knowledge, there are no previous reports of a free-floating thrombus in the common carotid artery.Case Report:A 45-year-old woman who was previously healthy and on no medications presented with acute hemiparesis and aphasia. Following testing that included carotid duplex and trancranial Doppler ultrasonography, diffusion-weighted magnetic resonance imaging, and digital subtraction angiography, the patient underwent emergency open embolectomy. No underlying wall defect was seen at the time of imaging or surgery. No obvious hypercoagulable state could be identified. Her NIH Stroke Scale score improved from 26 at admission to 2 at three months and 1 at one year.Conclusions:Multimodal imaging may have improved diagnosis and management in this patient with a unique finding. The source of the thrombus remains obscure.

Neurosurgery, 1999

OBJECTIVE A N D IMPORTANCE: Infratentorial empyema, pituitary abscess, and septic cavernous sinus... more OBJECTIVE A N D IMPORTANCE: Infratentorial empyema, pituitary abscess, and septic cavernous sinus thrombophlebitis are all rare and potentially lethal con ditions. The occurrence of all three in a single patient has not previously been described. W e present such a case occurring in a young, otherwise healthy man. C LIN IC A L PRESENTATION: A 26-year-old man w ith a rem ote history of sinusitis developed rapidly progressive headache, fever, right eye pain, swelling, proptosis, and visual im pairm ent. M agnetic resonance imaging demonstrated diffuse pansinusitis, including sphenoid sinusitis, and ex tension of inflam m ation and infection into the adjacent cavernous si nuses, pituitary gland, and posterior fossa. INTERVENTIO N: Urgent drainage of the ethmoid and maxillary sinuses was performed; pus was not identified. The patient continued to deteriorate clinically with worsening of visual acuity. Computed tomography of the head performed the next day revealed worsening hydrocephalus and an enlarging posterior fossa subdural empyema. Urgent ventricular drainage and evacuation of the empyema was performed, and subsequently, the patient's clinical course improved. The microbiology results revealed alpha hemolytic streptococcus and coagulase-negative staphylococcus species. The patient survived but during the follow-up period had a blind right eye and pituitary insufficiency. C O N C L U S IO N : Paranasal sinusitis can have devastating intracranial se quelae. Involvem ent of the adjacent pituitary gland and cavernous sinuses can result in serious neurological m orbidity or m ortality, and retrograde spread of infection through the basal venous system can result in subdural or parenchymal brain involvem ent. A high index of suspicion and aggres sive medical and surgical treatm ent are crucial for patient survival, but the m orbidity rate remains high. O u r patient survived but lost anterior pituitary function and vision in his right eye.

Journal of Neurosurgery, 1998

✓ The authors present the case of a 34-year-old man struck over the left mastoid region by a hock... more ✓ The authors present the case of a 34-year-old man struck over the left mastoid region by a hockey puck, who suffered a fatal rupture of a left vertebral artery berry aneurysm. He became apneic within seconds of the injury and had no brainstem reflex within minutes. The postmortem examination showed massive subarachnoid hemorrhage in the posterior fossa and the remnants of a berry aneurysm near the intradural origin of the left vertebral artery, 11 mm proximal to the posterior inferior cerebellar artery. Rupture of a saccular aneurysm as a result of head trauma is rare. This is the first reported case of a posterior circulation aneurysm rupture as a result of head trauma.

Journal of Neurology, Neurosurgery & Psychiatry, 1994

Ipsilateral third nerve palsy with early pupillary enlargement is an important sign of transtento... more Ipsilateral third nerve palsy with early pupillary enlargement is an important sign of transtentorial herniation from a supratentorial mass lesion. A case of frontal, intraparenchymal haemorrhage is reported in which the first ocular manifestation of transtentorial herniation was enlargement of the contralateral pupil. The ipsilateral pupil dilated only after complete oculomotor palsy of the contralateral eye. After partial frontal lobectomy and removal of blood clot, the ipsilateral third nerve recovered before the contralateral third nerve. Clinical findings localised the contralateral third nerve lesion to an extra-axial site. The possible mechanisms of contralateral third nerve compression are discussed. This seems to be the first example of pupillary enlargement as a false localising sign from a contralateral, supratentorial, intraparenchymal mass lesion.

Epilepsy Research, 2007

Background and purpose: In patients with discordant results, non-localizing EEG, or bitemporal se... more Background and purpose: In patients with discordant results, non-localizing EEG, or bitemporal seizure onset, intracranial monitoring is done to confirm the seizure onset. Our aim was to assess the yield of intracranial recordings in patients with different clinical scenarios. Methods: The records of all patients who underwent prolonged intracranial EEG monitoring (IEM) at the London Health Sciences Centre, University of Western Ontario, Canada, between 1993 and 1999, identified using our EEG patient database in continuous use since December 1972, were reviewed. Patients were analyzed in the following groups according to perceived increasing degrees of uncertainty of epileptic zone localization-group 1: lesion on MRI congruent with focal ictal and interictal scalp EEG, but findings are subtle and of low level of certainty (n = 13), group 2: focal MRI, focal ictal and multifocal interictal scalp EEG (n = 11), group 3: focal MRI, non-localizing or incongruent scalp EEG (n = 73), group 4: normal of multifocal MRI, focal ictal scalp EEG (n = 11), group 5: multifocal MRI, non-localizing scalp EEG (n = 18), and group 6: normal MRI, multifocal scalp EEG (n = 36). Results: One hundred and seventy one patients underwent IEM at the London Health Sciences Centre between 1993 and 1999. All patients had localization-related epilepsy, plus or minus secondary generalization. IEM was helpful overall in 86% of patients, in 69% of group 1, 36% of group 2, 90% of group 3, 81% of group 4, 100 of group 5 and 92% of group 6. Conclusions: Our study shows that the yield of the IEM was higher in the groups of patients with lack of congruence between the MRI and the scalp EEG. The yield was lower in patients with congruent but subtle or uncertain scalp EEG and MRI findings.

Critical Care Medicine, 2012

Acta Neuropathologica, 1997

A fatal case of inadvertent intrathecal entry of an ionic contrast medium during a nephrogram is ... more A fatal case of inadvertent intrathecal entry of an ionic contrast medium during a nephrogram is reported. The patient developed seizures and failed to regain consciousness following the event. Computerized tomography revealed extensive intraventricular and subarachnoid hyperdensity and cerebrospinal fluid analysis revealed markedly elevated protein content. At autopsy a traumatic communication between the kidney and thecal sac was identified. Histopathological examination revealed cytoplasmic shrinkage and eosinophilia, nuclear pyknosis and karyorrhexis in neocortical neurons. Central chromatolysis was seen in brain stem motor nuclei and anterior horn cell neurons. The neuropathological findings appear to be on the basis of direct neurotoxicity from the contrast medium and excitotoxic injury secondary to seizure activity. Inadvertent intrathecal administration of ionic contrast media is a rare occurrence with often fatal consequences despite aggressive medical management.

Journal of neurosurgery. Spine, 2014

Perineural cysts are common lesions of the sacral spine. They have rarely been reported in a pres... more Perineural cysts are common lesions of the sacral spine. They have rarely been reported in a presacral location, leading to their misdiagnosis as a gynecological lesion. The authors report the second such case, in a patient undergoing fenestration of what was presumed to be a benign pelvic cyst, and the resultant high-flow CSF leak that occurred. They describe the clinical presentation and manifestations of intracranial hypotension, as well as the pertinent investigations. They also review the literature for the best management options for this condition. Although they are uncommon, large perineural cysts should be included in the differential diagnosis when examining patients with a pelvic lesion. Appropriate imaging investigations should be performed to rule out a perineural cyst. The CSF leak that occurs from iatrogenic cyst fenestration may not respond to traditional first-line treatments for intracranial hypotension and may require early surgical intervention. The authors would...

Surgical Neurology, 2007

Background: Esophageal perforation from anterior cervical instrumentation migration is an uncommo... more Background: Esophageal perforation from anterior cervical instrumentation migration is an uncommon but potentially highly morbid or even fatal complication. Early recognition and aggressive investigation and treatment are essential to ensure good outcome. Case Description: A 58-year-old man underwent C6 vertebrectomy and C5-7 interbody fusion with a cage and anterior cervical plate. After surgery he developed fever and recurrence of his symptoms and deficits, but was managed expectantly. He was then referred to the author's institution. A barium swallow demonstrated an esophageal fistula (a Gastrograffin swallow was falsely negative) caused by a migrated screw; serial radiographs confirmed its passage through the gastrointestinal tract. Revision surgery was required to repair the perforation and reconstruct the cervicothoracic spine. Intraoperative esophageal injection of methylene blue was helpful in demonstrating the site of leakage. Despite a prolonged postoperative course complicated by pulmonary embolus, the patient recovered with minimal residual deficit, and continues to do well 2 years later. Conclusions: A high index of suspicion followed by aggressive investigation are crucial in the setting of unexpected neck pain, new neurologic deficit, fever, or swallowing difficulties in the early postoperative period after anterior cervical spine instrumentation. If esophageal perforation is suspected, a barium swallow is recommended over Gastrograffin, which, although less irritating to the surrounding tissues, may be falsely negative. Intraoperative methylene blue injection into the esophageal lumen is useful in identifying the site of perforation.

Effet de la dexaméthasone sur la morbidité suite à l'insertion d'électrodes sous-durales-une étud... more Effet de la dexaméthasone sur la morbidité suite à l'insertion d'électrodes sous-durales-une étude randomisée à double insu contrôlée par placebo. Introduction: La surveillance effractive au moyen d'électrodes sous-durales (ÉSD) dans l'investigation de l'épilepsie réfractaire au traitement médical peut être associée à une morbidité postopératoire immédiate dont la céphalée, les nausées, les vomissements, l'hyperthermie et le méningisme. Nous avons évalué si la déxaméthasone administrée pendant la période périopératoire pouvait réduire ces symptômes. Méthodes: Trente patients qui devaient subir l'insertion d'ÉSD ont été répartis de façon aléatoire au traitement à la déxaméthasone une heure avant la chirurgie et à dose décroissante dans les 72 heures après la chirurgie ou à recevoir un placebo. La douleur, le soulagement de la douleur, les nausées, le soulagement des nausées, la température et le méningisme ont été évalués régulièrement en période postopératoire et les besoins en médicaments analgésiques, antipyrétiques et antiémétiques ont été notés. Résultats: Un patient a été exclu du groupe recevant la dexaméthasone à cause de données manquantes. En ce qui concerne la douleur postopératoire, la dexaméthasone semblait être bénéfique, bien que les données n'aient pu être analysées de façon plus poussée à cause d'une interaction entre le traitement et le temps. Le groupe recevant de la dexaméthasone avait une température significativement plus basse ainsi qu'un meilleur score de soulagement des nausées. La différence entre les groupes quant au soulagement de la douleur, aux nausées et au méningisme n'atteignait pas le seuil de la significativité. Les effets bénéfiques de la dexaméthasone avaient un début tardif, une durée limitée et étaient variables pendant la période d'observation. Conclusion: La dexaméthasone semble jouer un rôle dans la réduction immédiate de la morbidité après l'insertion d'ÉSD mais son effet est variable pendant la période postopératoire: le début est retardé et l'effet est d'une durée limitée. D'autres études sont nécessaires pour déterminer quel est le schéma posologique idéal.

The Canadian Journal of Neurological Sciences Le Journal Canadien Des Sciences Neurologiques, May 1, 2000

Awake craniotomy is performed using neurolept analgesia, a term first proposed by De Castro and M... more Awake craniotomy is performed using neurolept analgesia, a term first proposed by De Castro and Mundeleer in 1959 to describe a state of indifference and immobilization produced by the combined administration of the neuroleptic haloperidol and the narcotic analgesic phenoperidine. 1 Following numerous modifications, the combination of droperidol and fentanyl became the most widely used method for producing neurolept analgesia, which is distinguished from neurolept anaesthesia by the preservation of consciousness, although the two terms are often used interchangeably. The technique of awake craniotomy demands, perhaps more so than any other neurosurgical ABSTRACT: In 1886, Victor Horsley excised an epileptogenic posttraumatic cortical scar in a 23-yearold man under general anaesthesia and discussed his choice of anaesthesia: "I have not employed ether in operations on man, fearing that it would tend to cause cerebral excitement; chloroform, of course, producing on the contrary, well-marked depression." His concerns regarding anaesthesia are reiterated 100 years later as evidenced by the ongoing controversy over the choice of anaesthetic in surgical procedures for epilepsy. The current controversies regarding the necessity for local anaesthesia in temporal lobe epilepsy operations concern the utility of electrocorticography in surgical decision making, its relationship to seizure outcome and the value of intraoperative language mapping in dominant temporal lobe resections. The increasing sophistication of pre-operative investigation and localization of both areas of epileptogenesis and normal brain function and the introduction of minimally invasive surgical techniques and smaller focal resections are changing the indications for local anaesthesia in temporal lobe epilepsy. Thus, indications which were previously absolute are now perhaps relative. This article reviews the current indications for craniotomy under local anaesthesia in the surgical treatment of temporal lobe epilepsy. RÉSUMÉ: La crâniotomie sous anesthésie locale: indications et techniques dans le traitement chirurgical de l'épilepsie temporale. En 1886, Victor Horsley a excisé une cicatrice corticale post-traumatique épileptogène chez un jeune homme de 23 ans sous anesthésie générale et a discuté du choix de l'anesthésie: "je n'ai pas utilisé l'éther pour les interventions chez l'homme par crainte de causer de l'excitation cérébrale; le chloroforme, bien entendu, produit au contraire une dépression marquée." Ses inquiétudes concernant l'anesthésie sont réitérées 100 ans plus tard comme en témoigne la présente controverse sur le choix de la substance anesthésique pour la chirurgie de l'épilepsie. Les controverses actuelles concernant la nécessité d'une anesthésie locale dans la chirurgie de l'épilepsie temporale concernent l'utilité de l'électrocorticographie comme aide à la décision au cours de la chirurgie, sa relation aux résultats et sa valeur pour la cartographie du langage pendant l'intervention dans la résection d'un lobe temporal dominant. L'investigation préopératoire de plus en plus sophistiquée, la localisation des zones épileptogènes et des zones normales, l'introduction de techniques chirurgicales très peu effractives et les résections focales plus limitées changent les indications pour l'anesthésie locale dans l'épilepsie temporale. Ainsi, les indications qui étaient antérieurement absolues sont probablement relatives. Cet article revoit les indications actuelles de la crâniotomie sous anesthésie locale dans le traitement chirurgical de l'épilepsie temporale.

Journal of Neuro-Oncology, 1993

We describe a 5 year old boy with a 5.5 cm right frontal lobe brain metastasis from primary clear... more We describe a 5 year old boy with a 5.5 cm right frontal lobe brain metastasis from primary clear cell sarcoma of the kidney without evidence of tumor-associated edema or contrast enhancement on either computed tomography or magnetic resonance imaging. The metastasis regressed but did not disappear with chemotherapy and dexamethasone, and the residual tumor was removed surgically. On histological examination the majority of the tumor was composed of mature connective tissue with a rim of typical renal clear cell sarcoma cells at the brain-tumor interface. The avascular and desmoplastic nature of the metastasis may explain the unusual radiographic features. Brain metastases from this tumor have only infrequently been reported; therefore a brief review of this rare tumor is provided.