Alok Ranjan

Ascorbic acid and focal cerebral ischaemia in a primate model

SummaryNeuronal cell damage following ischaemia is postulated to be due to free radical induced lipid peroxidation, and ascorbic acid is supposedly an important non-enzymatic scavenger of such free radicals. This study was undertaken to evaluate the protective effect of ascorbic acid on the brain in a primate model after focal cerebral ischaemia. Consumption of ascorbic acid in the monkey brain following ischaemia and its effect on macroscopic infarct size as demonstrated by 2, 3, 5, Triphenyl tetrazolium chloride (TTC) staining were used as parameters.The monkeys in the treated group were given 1 gram ascorbic acid parenterally every day for six days. The mean level of total ascorbic acid in right basal ganglia was 35.1±4.2 μg/mg of protein in the treated group as opposed to 22.9±2.1 μg/mg of protein in the nontreated group both before ischaemia. After right middle cerebral artery occlusion to produce focal cerebral ischaemia, the total ascorbic acid in the right basal ganglia 2 hours post ischaemia was 13.3±3.1 μg/mg of protein in the treated group as opposed to 9±1.6 μg/mg of protein in the untreated group. The average consumption of total ascorbic acid was 21.8 μg/mg of protein in the treated group and 13.9 μg/mg of protein in the nontreated group.Macroscopic infarct size as determined by TTC staining in the right cerebral hemisphere was 11.7±6.9 in treated group whereas it was 24.4±4.4 (expressed as percentage of right hemisphere) in the non-treated group. There was significant reduction in the size of the infarct in the treated group.A short course of mega-dose Ascorbic acid therapy was found to significantly decrease the macroscopic infarct size. Pretreatment with ascorbic acid enhanced its storage and utilization during ischaemia resulting in its protective effect.

Rosette-forming glioneuronal tumors: a report of two cases.

Rosette-forming glioneuronal tumor, a mixed glial and neuronal tumor, is a relatively new entity in tumors of the central nervous system, included in 2007 classification published by World Health Organization (WHO). It was initially described to occur in and around the fourth ventricle; however, recent case series have reported other locations also. Their occurrence in supratentorial and spinal locations has recently been reported. We report two cases of rosette-forming glioneuronal tumors, one in the midbrain and one in a suprasellar location, and review the literature.

Exosomes as a biomarker platform for detecting epidermal growth factor receptor–positive high-grade gliomas

OBJECTIVE High-grade glial brain tumors are often characterized by an elevated expression of the tumorigenic epidermal growth factor receptor variant III ( EGFRvIII). The authors sought to establish a clinically adaptive protocol as a noninvasive diagnostic tool for EGFRvIII detection through serum exosomes. METHODS Purity of serum exosome/RNA was confirmed by electron microscopy and flow cytometry and through an RNA bioanalyzer profile. EGFRvIII amplification was initially established by semiquantitative polymerase chain reaction in tumor tissues and exosomes. Diagnostic performance of EGFRvIII transcript in tissue versus exosome was determined using a 2 × 2 clinical table approach. Overall survival was determined using Kaplan-Meier analysis. RESULTS The EGFRvIII transcript was detected in 39.5% of tumor tissue samples and in 44.7% of their paired serum exosome samples; 28.1% of biopsy tumors coexpressed wild-type EGFR and EGFRvIII. Tissue EGFRvIII amplification served as the reference-positive control for its paired serum expression. The overall clinical sensitivity and specificity of semiquantitative exosome EGFRvIII polymerase chain reaction detection assay in serum were 81.58% (95% CI 65.67%-92.26%) and 79.31% (95% CI 66.65%-88.83%), respectively. Age, sex, tumor location, and side of the body on which the tumor was located had no effect on the detection rate of exosomal EGFRvIII transcript. EGFRvIII expression either in exosomes or tissue correlated with poor survival. CONCLUSIONS The authors established a serum-based method for detection of EGFRvIII in high-grade brain tumors that might serve as an optimal noninvasive method for diagnosing EGFRvIII-positive high-grade gliomas.

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS): A case report and review of literature

Chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (CLIPPERS) is a recently described inflammatory disease of central nervous system with distinct clinical and radiological features. The etiopathogenesis of this rare entity remains to be understood. The histopathological findings closely resemble chronic inflammatory diseases like sarcoidosis and malignancies like lymphoma. With advancements in serology, immunopathology and radiology CLIPPERS is identified as a distinct entity that differs considerably in its clinical presentation, immunopathology, radiological findings and response to steroids. We describe a case that presented to us with progressive quadriparesis and lower cranial nerve deficits whose radiological and pathological findings were consistent with CLIPPERS. The patient had a good outcome with long term immunosuppression.

Endoscopic management of CSF rhinorrhea

BACKGROUND Transnasal endoscopic repair has become the treatment of choice for most anterior cranial and all sphenoid sinus breaches. The aim of this paper is to evaluate the results of endoscopic management of cerebrospinal fluid (CSF) rhinorrhea in a tertiary care center in South India. MATERIALS AND METHODS A retrospective analysis of 40 consecutive patients who underwent endoscopic repair of CSF rhinorrhea between 2010 and 2013 was performed. Endoscopic procedure consisted of defining the defect and removal of mucosa for 3-4 mm surrounding it. Repair was done using septal cartilage (for defects involving sphenoid sinus where sinus was packed with fat), fascia lata, oxidized cellulose, and fibrin sealant. Lumbar drain was placed for 2-4 days in selected cases. A lumbar-peritoneal shunt was inserted in patients with spontaneous CSF rhinorrhea and high opening lumbar CSF pressure. RESULTS Spontaneous CSF leaks were more common in middle-aged females, whereas posttraumatic CSF leaks were common in young adult males. The success rates following first surgery for patients with posttraumatic, spontaneous, and postprocedural CSF leaks were 85.7, 81.8, and 75%, respectively, which improved to 95.7, 100, and 100% following second procedure, respectively. Technical failures, poor graft uptake because of radiation therapy, location of leak in the lateral sphenoid recess, lumbar peritoneal shunt malfunction, and poor healing of skull base fractures were responsible for recurrence of leak. CONCLUSION Team work between neurosurgeons and otorhinolaryngologists with attention to identification of site of leak, preparation of graft bed, securing the graft in place, and postoperative care is critical to achieve a high level of success for endoscopic repair of CSF rhinorrhea.

Stereotactic craniotomy for lesions in eloquent areas

CT compatible stereotactic systems are being increasingly used in the management of intracranial mass lesions. This study deals with the use of BRW stereotactic system for excisional biopsy of small (<30 mm), superficial, solitary cerebral lesions located in eloquent areas. Out of a total of 113 cases of stereotactic craniotomy carried out in the department since 1987, 78 fitted the above criteria. Out of these 78 patients, 70 lesions (90%) were less than 20 mm in size. Local anaesthesia was used in 10 cases (13%) whereas the rest had general anaesthesia. Cortical incision using standard techniques were used in 51 patients (65%), whereas in 27 patients (35%) excisional biopsy was done using trans-sulcal microsurgical techniques. Twenty-one (41%) patients had some degree of neurological deficit in the immediate postoperative period when a cortical incision was used compared to 4 patients (15%) when a trans-sulcal microsurgical excisional biopsy was done (P < 0.05). However, significant neurological deficits were present in 10 cases (12.8%) and all but two had had cortical incisions. When assessed one month after surgery significant residual deficit was present in only 2 patients (2.5%) who had had cortical incisions. There was no postoperative infection or mortality in this series. CT guided stereotactic craniotomy coupled with trans-sulcal microsurgical techniques can be safely used for the excisional biopsy of small superficial lesions located in eloquent areas of the brain.

Arteriovenous fistula of the filum terminale misdiagnosed and previously operated as lower lumbar degenerative disease.

Filum terminale arteriovenous fistula (FTAVF) presenting as a cause of failed back surgery syndrome is a rare entity. We report a 48-year-old male patient who presented with clinical features of a conus medullaris/cauda equina lesion. He had upper and lower motor neuron signs in both the lower limbs with autonomic dysfunction. The patient was misdiagnosed and was operated twice earlier for lumbar canal stenosis and disc prolapse. After reviewing his clinical and radiological findings a diagnosis of FTAVF was made. He underwent surgery and there was a significant improvement in his neurological functions. We discuss the case and review the literature on FTAVFs.