Ranjith K. Moorthy

Management of brain abscess: an overview

Recent advances in neuroimaging have resulted in a marked decrease in morbidity and death due to brain abscesses. The advent of computed tomography-guided stereotaxy has reduced morbidity in patients with deep-seated abscesses. Empirical therapy is best avoided in the present era, particularly given the availability of stereotactic techniques for aspiration and confirmation of diagnosis. Despite these advances, management of abscesses in patients with cyanotic heart disease and in immunosuppressed patients remains a formidable challenge. Unusual as well as more recently recognized pathogens are being isolated from abscesses in immunosuppressed patients. The authors provide an overview of the management of brain abscesses, highlighting their experience in managing these lesions in patients with cyanotic heart disease, stereotactic management of brain abscesses, and management of abscesses in immunosuppressed patients.

The transpedicular approach in the management of thoracic spine tuberculosis: a short-term follow up study.

Study Design. A retrospective descriptive assessment of the clinical and radiologic outcomes of 11 patients who underwent transpedicular decompression for thoracic spine tuberculosis. Objectives. To study the neurologic and radiologic outcomes in patients who underwent transpedicular decompression for thoracic spine tuberculosis. Summary of Background Data. Several approaches have been used in the management of thoracic spine tuberculosis to achieve the goals of decompression of the cord followed by immobilization and antituberculous therapy. These range from conservative regimens of computed tomography-guided biopsy followed by bed rest and drug therapy to radical surgeries that involve extensive debridement of the vertebral body followed by instrumentation. The authors report their experience with a “middle path” regimen of transpedicular decompression followed by external immobilization and antituberculous therapy. Methods. The charts of 11 patients were reviewed retrospectively for clinical outcome, and kyphotic angle was measured on the follow-up radiographs to ascertain progression of kyphosis. Results. There was no worsening of the neurologic status in any patient, and 10 of the 11 patients returned to functional activity. There was no significant progression of kyphosis. Conclusions. Our results show that the transpedicular approach is a viable and safe surgical option for ventral decompression in thoracic spine tuberculosis, followed by chemotherapy for 18 months and immobilization in an alkathene shell for 3 months.

Decompressive craniectomy in cerebral venous thrombosis: a single centre experience

Background Cerebral venous thrombosis (CVT) is an important cause for stroke in the young where the role for decompressive craniectomy is not well established. Objective To analyse the outcome of CVT patients treated with decompressive craniectomy. Methods Clinical and imaging features, preoperative findings and long-term outcome of patients with CVT who underwent decompressive craniectomy were analysed. Results Over 10 years (2002–2011), 44/587 (7.4%) patients with CVT underwent decompressive craniectomy. Diagnosis of CVT was based on magnetic resonance venography (MRV)/inferior vena cava (IVC). Decision for surgery was taken at admission in 19/44 (43%), within 12 h in 5/44 (11%), within first 48 h in 15/44 (34%) and beyond 48 h in 10/44 (22%). Presence of midline shift of ≥10 mm (p<0.0009) and large infarct volume (mean 146.63 ml; SD 52.459, p<0.001) on the baseline scan influenced the decision for immediate surgery. Hemicraniectomy was done in 38/44 (86%) and bifrontal craniectomy in 6/44 (13.6%). Mortality was 9/44 (20%). On multivariate analysis (5% level of significance) age <40 years and surgery within 12 h significantly increased survival. Mean follow-up was 25.5 months (range 3–66 months), 26/35 (74%) had 1 year follow-up. Modified Rankin Scale (mRs) continued to improve even after 6 months with 27/35 (77%) of survivors achieving mRs of ≤2. Conclusions This is the largest series on decompressive craniectomy for CVT in literature to date. Decompressive craniotomy should be considered as a treatment option in large venous infarcts. Very good outcomes can be expected especially if done early and in those below 40 years.

Management of hydrocephalus associated with occipital encephalocoele using endoscopic third ventriculostomy: report of two cases

BACKGROUND Occipital encephalocoele is the most common cranial dysraphism in the western hemisphere and is often complicated by hydrocephalus. Management of hydrocephalus and reducing the CSF pressure is crucial in preventing dehiscence at the site of the encephalocoele repair. METHODS Two female patients had presented with occipital encephalocoeles. The first patient (aged 42 days) had undergone repair of the occipital encephalocoele and then developed hydrocephalus with recurrence of the encephalocoele. The second patient (aged 12 months) had hydrocephalus associated with an occipital encephalocoele at initial presentation.Both the patients underwent endoscopic third ventriculostomy (ETV) through a right frontal burr hole. In the first patient, ETV was performed after shunt dysfunction at the age of 9 months. Because she presented with recurrence of the encephalocoele 15 months later, a repeat endoscopic third ventriculostomy was performed. She required a ventriculoperitoneal shunt during the same admission because of the early failure of the ventriculostomy. In the second patient, it was performed before the encephalocoele repair, both ETV and the repair being conducted under the same anesthesia. ETV was performed using a rigid scope and the perforation in the third ventricular floor was enlarged using a No. 4 Fogarty catheter. RESULTS The first patient had no recurrence of encephalocoele at follow-up of 10 months but she presented with recurrence of the occipital encephalocoele after 15 months. The second patient had no evidence of recurrence at follow-up after 16 months. The lateral and third ventricular volumes had decreased in both the patients at initial follow-up. CONCLUSION ETV can be an effective treatment option for encephalocoele-associated hydrocephalus, even in children under the age of 1 year. It may obviate the need for placement of CSF shunts that have a risk of infection and dysfunction. However, delayed failure of ETV may occur as seen in our first patient, indicating the need for careful and long-term follow-up.

Status of Stereotactic Biopsy in Children with Brain Stem Masses: Insights from a Series of 106 Patients

Background:There is no consensus on the indications for stereotactic biopsy for brain stem masses in children. Objectives: We analyzed the results of stereotactic biopsy for brain stem masses in 106 consecutive children to define current indications for this surgery. Methods: We performed a retrospective review of inpatient summaries, stereotactic worksheets and radiological investigations of 106 consecutive patients, under the age of 18 years, who underwent CT-guided stereotactic biopsies for brain stem lesions between 1987 and 2008. Patients were divided into two eras: era I from 1987 to 1997 and era II from 1998 to 2008. Results: 91 children underwent a biopsy in era I, and 15 had the procedure in era II, this difference clearly indicating the impact of the availability of magnetic resonance imaging. There was no difference in the proportion of diffuse lesions biopsied in both eras. Astrocytoma was the most frequently diagnosed pathology in both eras accounting for nearly 90% of biopsies. Inflammatory masses were diagnosed in less than 10% of patients. There was no mortality or permanent morbidity. Mortality, on follow-up, in children with diffuse low- and high-grade astrocytoma was similar. Conclusions:CT-guided stereotactic biopsy for brain stem masses in children is safe and is presently indicated in ruling out an inflammatory pathology of an enhancing mass of the brain stem.

Conservative antibiotic policy in patients undergoing non-trauma cranial surgery does not result in higher rates of postoperative meningitis: An audit of nine years of narrow-spectrum prophylaxis

Abstract Objective. To audit the efficacy of a conservative prophylactic antibiotic policy in patients undergoing non-trauma cranial surgery. Materials and methods. Prospectively collected infection data in consecutive patients who underwent non-trauma cranial surgeries in one neurosurgical unit between 1 January 2003 and 31 December 2011 were reviewed. Depending on the surgery performed, a one-day course of intravenous chloramphenicol or a single dose of ceftriaxone was used as the prophylactic antibiotic therapy. Patients with clinical and CSF features suggestive of meningitis were considered to have postoperative meningitis if the CSF culture was positive. Results. Bacterial meningitis was diagnosed in 27 (0.8%) of 3401 patients included in the study. Multidrug-resistant (MDR, organisms that were resistant to two or more first line of antibiotics) organisms were grown from CSF in four patients with bacterial meningitis (0.1%). There were two deaths among the 27 patients with successful treatment of meningitis in the other 25 patients. Conclusion. In non-trauma neurosurgical patients undergoing elective cranial procedures, a conservative prophylactic antibiotic policy is effective in achieving low rates of bacterial meningitis with low rates of MDR infections. Therefore, our results make a compelling case for a conservative prophylactic antibiotic policy.

Endoscopic third ventriculostomy for hydrocephalus: A review of indications, outcomes, and complications

Endoscopic third ventriculostomy (ETV) has been in vogue for the past two decades, as a tool in the armamentarium of the neurosurgeon, for the management of hydrocephalus. Its utility has been proven consistently in congenital / acquired aqueductal stenosis, although the outcomes in communicating hydrocephalus as well as hydrocephalus secondary to other etiologies have not been as impressive. It is a relatively safe procedure with the appropriate selection of patients with a low rate of permanent morbidity. This review aims to define the current indications, management outcomes, and complications of ETV.

Changes in cervical spine curvature in pediatric patients following occipitocervical fusion.

ObjectiveThe study aims to assess changes in cervical spine curvature following occipitocervical fusion (OCF) in the pediatric population.MethodsIn a retrospective study, the angle of sagittal curvature and whole cervical spine alignment were determined in the preoperative, immediate postoperative, and follow-up radiographs in 14 patients (<20 years of age) who underwent OCF for developmental atlantoaxial instability between 1995 and 2006. At follow-up, the mean angle of sagittal curvature showed a statistically significant increase from 22+/−10.1° immediately following surgery to 35.9+/−18° at follow-up (p = 0.001). Six patients had exaggerated lordosis (defined as >10° increase in the angle of sagittal curvature). The sagittal curvature angle did not show any worsening in seven patients following removal of the implant.ConclusionsOCF in the pediatric population can result in an increase in the lordotic curvature of the cervical spine that might stabilize following removal of the metal implant within a year of surgery.

Assessment of Memory and New Learning Ability following Stereotaxy-Guided Transcortical Resection of Anterior Third Ventricular Colloid Cysts

In a prospective study, memory and new learning ability functions were assessed pre-operatively (17 patients) and in the early post-operative period (22 patients) at 7–26 days following surgery in patients undergoing stereotactic transcortical excision of their colloid cysts. Pre-operative assessment detected impaired memory in 5 patients, 2 of whom had no memory-related complaints. Impaired new learning ability was detected pre-operatively in 7 patients. There was a statistically non-significant trend towards improvement in the dysfunction scores post-operatively in most patients. No correlation was detected between the cyst size, presence of raised intracranial pressure at presentation, hydrocephalus and the pre-operative dysfunction scores. Stereotactic transcortical resection of colloid cysts does not impair these functions in the majority of patients and might improve these functions in some. In the absence of clinical or radiological predictors of dysfunction of memory and new learning ability, pre-operative neuropsychological assessment has a role in detecting impaired memory and new learning ability in patients with anterior third ventricular colloid cysts who may not even complain of them.

Stereotactic radiosurgery for intracranial arteriovenous malformations: A review

Stereotactic radiosurgery (SRS) has proven to be an effective strategy in the management of intracranial arteriovenous malformations (AVMs) in children and adults over the past three decades. Its application has resulted in lowering the morbidity and mortality associated with treatment of deep-seated AVMs. SRS has been used as a primary modality of therapy as well as in conjunction with embolization and microsurgery in the management of AVMs. The obliteration rate after SRS has been reported to range from 35% to 92%. Smaller AVMs receiving higher marginal doses have obliteration rates of 70% and more. The median follow-up reported in most series is approximately 36-40 months. The median time to obliteration has been reported to be approximately 24-36 months in most series. Radiation-induced neurological complications have been reported in less than 10% of patients, with a 1.5%-6% risk of developing a new permanent neurological deficit. The bleeding rate during the latency to obliteration has been reported to be approximately 5%. This review describes the experience reported in literature with respect to the indications, dosage, factors affecting obliteration rate of AVMs, and complications after SRS.