Amandeep Kumar

Distraction, compression, and extension reduction of basilar invagination and atlantoaxial dislocation: a novel pilot technique.

BACKGROUND The management of basilar invagination (BI) and atlantoaxial dislocation (AAD) is a challenge. OBJECTIVE To describe a new innovative method to reduce BI and AAD through a single-stage posterior approach. METHODS Thirty-five patients had irreducible BI and AAD (May 2010 to April 2012). In all patients, reduction of AAD and BI was achieved by using an innovative method of distraction and spacer placement, followed by compression and extension. A C1 lateral mass/C2 translaminar screw was performed in cases where the C1 arch was not assimilated, and occipito-C2 translaminar screw fixation was performed in cases where the C1 arch was assimilated. RESULTS Thirty-two of 35 (94%) patients improved clinically and 2 patients had stable symptoms (mean Nurick postoperative score = 1.4; preoperative score = 3.7). AAD reduced completely in 33/35 patients and >50% in 2. BI improved significantly in all patients. Solid bone fusion was demonstrated in 24 patients with at least 1-year follow-up (range, 12-39 months; mean, 19.75 + 7.09 months). The duration of surgery was 80 to 190 minutes, and blood loss was 90 to 500 mL (mean, 170 ± 35 mL). There was 1 death because of cardiac etiology and 1 morbidity (wound infection). CONCLUSION Distractive compressive extension and reduction of BI and AAD seems to be an effective and safe method of treatment. It is different from the earlier described techniques, because it is the first procedure that uses a spacer not, only for distraction, but also as a pivot to perform extension to reduce the AAD.

Prognostic value of MIB-1, p53, epidermal growth factor receptor, and INI1 in childhood chordomas

BACKGROUND Chordomas are slow-growing tumors and most commonly involve the sacrum and clivus. Multiple recurrences are frequent. Childhood chordomas are rare and often show exceptionally aggressive behavior, resulting in short survival and a high incidence of metastatic spread. OBJECTIVE This study examined the histologic features and immunohistochemical profile of pediatric chordomas and compared them with their adult counterparts. METHODS Nine pediatric and 13 adult cases were included in the study. Childhood chordomas were classified into conventional, atypical, and poorly differentiated types. Immunohistochemistry was performed for cytokeratin, epithelial membrane antigen, vimentin, S100, brachyury, p53, INI1, epidermal growth factor receptor (EGFR), and CD117. Cytogenetic analyses were performed in a subset of tumors for SMARCB1/INI1 locus on 22q chromosome by fluorescent in situ hybridization (FISH) and analysis of the SMARCB1/INI1 gene sequence. RESULTS All tumors showed expression of cytokeratin, epithelial membrane antigen, S100, vimentin, brachyury, and EGFR. Atypical morphology, p53 expression, higher MIB-1 labelling index (LI), and INI1 loss were more frequently seen in pediatric chordomas as compared with adults. None of the tumors showed CD117 expression. No point mutation in the SMARCB1/INI1 gene was noted in the tumors examined; however, 4 pediatric and 1 adult chordoma showed loss of this locus on FISH analysis. CONCLUSIONS A subset of pediatric chordomas with atypical histomorphologic features needs to be identified, as they behave in an aggressive manner and require adjuvant therapy. Pediatric chordomas more frequently show p53 expression, INI1 loss, and higher MIB-1 LI as compared with adults, whereas EGFR expression is common to both.

The role of neuronavigation-guided functional MRI and diffusion tensor tractography along with cortical stimulation in patients with eloquent cortex lesions.

Abstract Objective. To effectively combine functional MRI (fMRI), diffusion tensor tractography (both guided by neuronavigation) along with cortical stimulation (CS) for surgery of eloquent cortex (EC) lesions. Materials and methods. Fifteen patients with lesions adjacent to the eloquent motor and sensory cortex were included. Preoperative fMRI and diffusion tensor imaging were performed and then integrated into the neuronavigation system. Intraoperative CS of sensory/motor cortex was performed to localize the EC under awake condition and this was correlated with areas active on fMRI utilizing neuronavigation. For excision of the deeper structures, CS, and tractography guided by neuronavigation were utilized. Results. A total of 127 cortical sites were evaluated with CS in 15 patients. The overall sensitivity, specificity, and accuracy of fMRI were 79%, 85%, and 82%, respectively, keeping the areas positive on CS as a referential parameter. Tractography helped in resecting the deeper areas of the tumor, but was not very accurate due to brain shift. However, it was useful in roughly assessing the deeper areas close to the long tracts. The risk of developing persistent neurological deficits was 6%. Pathologies included gliomas in ten patients, cavernous malformation in two patients, meningioma in one patient, and focal cortical dysplasia and Dysembryonic neuroepithelial tumor in one patient each. Near total excision was achieved in 7/10 (> 95% excision) gliomas and a total excision in all others lesions. Conclusions. Lesions directly over the EC present a special surgical challenge. The challenge lies in excising these lesions without producing any deficits. These goals may be achieved better by combined use of multimodal neuronavigation (fMRI and tractography) and intraoperative mapping with CS under awake conditions.

Thoracic extraosseous, epidural, cavernous hemangioma: Case report and review of literature

A 40-year-old male presented with mid-thoracic backache and progressive, ascending, spastic, paraparesis for one year. Magnetic resonance imaging demonstrated an extraosseous, extradural mass, without any bone invasion at the T2-T4 vertebral levels, located dorsal to the thecal sac. The spinal cord was compressed ventrally. The lesion was totally excised after a T2-T4 laminectomy. Histopathological examination revealed a cavernous hemangioma. The authors reported this case and reviewed the literature, to explain why extraosseous, extradural, cavernous hemangiomas should be considered in the differential diagnosis of extradural thoracic compressive myelopathy.

Severe valproate induced hyperammonemic encephalopathy successfully managed with peritoneal dialysis

Valproic acid (VPA) is a commonly used drug for epilepsy, psychiatric disorders and migraine and is frequently used in neurosurgical intensive care units. Though most of its side-effects are mild and transient, certain idiosyncratic side-effects have been attributed to VPA. Valproate induced hyperammonemia (VIH) is one such side-effect. VIH can produce symptoms of encephalopathy known as valproate induced hyperammonemic encephalopathy (VHE). VIH and VHE usually respond to withdrawal of VPA. However, in some cases VHE can be unresponsive to supportive measures and severe enough to be life-threatening. In such cases, dialysis can be used to rapidly reverse hyperammonemia and VHE and can prove to be a lifesaving measure. We report such a case of VIH and life-threatening VHE in a postoperative neurosurgical patient that was managed successfully with peritoneal dialysis.

Umbilical CSF fistula: a rare complication of ventriculoperitoneal shunt

SummaryAn umbilical CSF fistula following a ventriculoperitoneal shunt is an extremely rare complication. We report a 28-year-old man who presented with leak of clear fluid from the umbilicus, one month after a ventriculo-peritoneal shunt revision. Shuntogram revealed communication between umbilicus and abdominal end of the catheter. He was managed successfully with shunt exteriorization, antimeningitic treatment, and later shunt re-insertion.

Fatal Superior Sagittal Sinus and Torcular Thrombosis After Vestibular Schwannoma Surgery: Report of a Rare Complication and Review of the Literature

BACKGROUND Cerebral venous sinus thrombosis (CVST) is a rare condition with the potential to cause severe morbidity and mortality. CVST can also occur after vestibular schwannoma (VS) surgery with the thrombosis of transverse and sigmoid sinus. However, there is not a single report of superior sagittal sinus (SSS) thrombosis after VS surgery reported in the literature. CASE DESCRIPTION A 45-year-old woman presented to our center with large left-sided solid cystic VS. On admission she was dehydrated, and after clinical stabilization, she underwent gross total excision of tumor through left retromastoid suboccipital craniotomy after cerebrospinal fluid drainage through an external ventricular drain. Surgery was uneventful, but postoperatively she had an episode of seizure. Immediate postoperative computed tomography (CT) brain scan was normal with good operative cavity. However, 24 hours later, she developed left-sided motor deficit, and a repeat CT scan showed right frontal parenchymal hemorrhage with intraventricular extension. On further evaluation, magnetic resonance venography showed entire SSS thrombosis, with patent bilateral transverse and sigmoid sinuses. She was not started on the anticoagulants in view of intracranial hemorrhage. Subsequently, she underwent right-sided decompressive craniectomy because there was progressive deterioration in her Glasgow Coma Scale, and she succumbed despite all efforts. Retrospectively, dehydration and intracranial hypotension could be likened to her sinus thrombosis. CONCLUSIONS This case underscores the significance of adequate optimization of the patients prior to surgery, besides adequate operative skills to avoid this rare but serious complication of SSS and torcular thrombosis after VS surgery.

Congenital spinal lipomas: Role of prophylactic surgery

Introduction: Congenital spinal lipomas constitute an important group of lesions causing tethered cord syndrome. Management of these lesions is challenging and role of prophylactic surgery for these lesions is still controversial. Hence, current study was undertaken with the aim to evaluate the role of prophylactic surgery in the management of these lesions. Materials and Methods: A total of 147 consecutive patients, treated over a period of 10 years (January 2001–December 2010), are retrospectively analyzed. Results: In our study, 93 patients had conus lipomas, 26 had filum lipomas and 28 had only lipomeningomyelocele. Boys and girls were almost equally represented. The age of patients at the time of surgery ranged from 15 days to 34 years with an average of 62 months (5.2 years). Neurological deficits were present in 101 (68) patients. The patients with neurological deficits were older in comparison to those neurologically intact (average age 6.2 versus 2.8 years, respectively). Difference in age between the two groups was statistically significant (P value 0.03). Neurological deterioration was observed in 8 (5) patients following surgery, out of which six patients developed transient deterioration and only two, had persisting deficits. None of the neurologically asymptomatic patients developed persistent neurological deficits. In the symptomatic group, nine patients (9) showed improvement in neurological status after surgery. Conclusions: In authors view, prophylactic surgery for congenital spinal lipomas is safe and effective. However, a well designed randomized controlled trial, to definitely and objectively prove the usefulness of prophylactic surgery is needed.

The Role of Endoscopic Lavage in Recalcitrant Multidrug-Resistant Gram-Negative Ventriculitis Among Neurosurgical Patients

INTRODUCTION Ventriculitis is a serious infection associated with high mortality even when both intravenous (IV) and intrathecal (IT) antibiotics are administered. Poor outcome in patients with ventriculitis indicates the need to be more aggressive in our attempts to expeditiously eradicate the infection. The purpose of this study was to evaluate the role of endoscopic lavage (EL) in patients with severe purulent ventriculitis, unresponsive to IV and IT antibiotics. METHODS All consecutive patients with severe ventriculitis caused by multidrug-resistant gram-negative bacteria, undergoing EL after failure of prolonged courses of IV and IT antibiotics, were included in the study. The outcome in all these patients was otherwise expected to be uniformly dismal. RESULTS There were 5 males and 2 females. The age range was one month to 45 years. All patients had frank intraventricular pus. Acinetobacter baumannii was the most common organism grown in cultures. Two patients had multiple bacterial growth in cerebrospinal fluid cultures. The duration of pre-EL IV/IT antibiotics ranged from 3 to 8 weeks. Microbiological cure was achieved in all (7/7) and clinical cure in 86% of patients (6/7). One patient died despite achieving cerebrospinal fluid sterilization 3 months later as a result of progressive white matter edema. CONCLUSIONS The addition of IT antibiotics has resulted in improved outcome in patients with ventriculitis; however, some patients continue to be unresponsive to antibiotics. EL can play a complementary role in eradicating such recalcitrant infections. EL should be considered in any patient with ventriculitis, if infection persists even after ∼7-10 days of IVand IT antibiotics.

Contralateral Anterior Interhemispheric Transparaterminal Gyrus Approach for Thalamopeduncular Pilocytic Astrocytoma in an Adult: Technical Report.

BACKGROUND Thalamopeduncular gliomas arise at the junction of the thalamus and cerebral peduncle and constitute a subgroup of thalamic gliomas. These are surgically challenging lesions because of close proximity to important neural structures including corticospinal tracts (CSTs) and the thalamus. These tumors usually displace CSTs anterolaterally or extend to the lateral ventricular surface. Such tumors can be removed by either temporal or transventricular approaches. However, if CSTs cover the entire lateral surface of tumor and tumor does not extend to the ventricular surface, temporal and transventricular approaches cannot be used because the trajectories of both approaches would pass through normal eloquent structures (CSTs and thalamus), and consequently there would be a very high risk of postoperative neurologic deficits developing. CASE DESCRIPTION A 50-year-old woman presented with contralateral hemiparesis. Radiologic evaluation revealed a right Thalamopeduncular glioma that displaced CSTs laterally and was covered by normal thalamus superiorly. Some CST fibers passed through the tumor. Because both lateral and superior surfaces were covered by eloquent structures, we used an anterior interhemispheric transparaterminal gyrus approach to access the tumor successfully and achieved subtotal excision. The patient had transient neurologic deterioration postoperatively that recovered to preoperative level within 2 weeks. CONCLUSIONS The anterior interhemispheric transparaterminal gyrus approach has not been described previously for accessing brainstem lesions. This approach can be used to access tumors of the cerebral peduncle that displace CSTs laterally and are covered by normal thalamus superiorly. The anterior interhemispheric transparaterminal gyrus approach adds to the armamentarium of neurosurgeons for treatment of cerebral peduncular lesions.