Endoscopic third ventriculostomy in post-tubercular meningitic hydrocephalus

Surgery for Central Nervous System Tuberculosis in Children

Tuberculosis (TB) is the second most common cause of death due to a single infectious agent worldwide after COVID-19. Central nervous system tuberculosis is widely prevalent in the world, especially in the developing countries and continues to be a socioeconomic problem. It is highly devastating form of tuberculosis leading to unacceptable levels of morbidity and mortality despite appropriate antitubercular therapy. The clinical symptoms are varied and nonspecific. They can be easily overlooked. Tuberculous meningitis is the most common presentation and its sequelae viz. vasculitis, infarction and hydrocephalus can be devastating. The ensuing cognitive, intellectual, and endocrinological outcome can be a significant source of morbidity and mortality, especially in resource constrained countries. Early diagnosis and treatment of tuberculous meningitis and institution of treatment is helpful in limiting the course of disease process. The diagnosis of CNS tuberculosis remains a formidable diagnostic challenge. The microbiological methods alone cannot be relied upon. CSF diversion procedures need to be performed at the appropriate time in order to achieve good outcomes. Tuberculous pachymeningitis and arachnoiditis are morbid sequelae of tuberculous meningitis. Tuberculomas present as mass lesions in the craniospinal axis. Tuberculous abscess can mimic pyogenic abscess and requires high index of suspicion. Calvarial tuberculosis is seen in children and responds well to antituberculous chemotherapy. Tuberculosis of the spinal cord is seen similar to intracranial tuberculosis in pathogenesis but with its own unique clinical manifestations and management. Multidrug-resistant tuberculosis is a formidable problem, and alternate chemotherapy should be promptly instituted. The pathogenesis, clinical features, diagnosis, and management of central nervous system tuberculosis in children are summarized. Heightened clinical suspicion is paramount to ensure prompt investigation. Early diagnosis and treatment are essential to a gratifying outcome and prevent complications.

Success and complication rates of endoscopic third ventriculostomy for tuberculous meningitis: a systematic review and meta-analysis

Because ventriculoperitoneal shunt (VPS) insertion for patients with hydrocephalus from tuberculous meningitis (TBM) can be complicated by shunt infection and malfunction, endoscopic third ventriculostomy (ETV) has been proposed as an alternative. The aim of this review was to determine the success, technical failure, and complication rates of ETV in TBM in a meta-analysis and determine which factors are predictive of outcome. The PubMed, Scopus, and CENTRAL databases were searched from inception to April 2020 for case series, cohort studies, or randomized controlled trials reporting success, technical failure, or complication rates. For studies with individual patient data available, logistic regression analysis was done to determine whether age, sex, clinical grade, and type of hydrocephalus on imaging was predictive of outcome. Eight studies with a total of 174 patients were included in the review. Using random-effects modeling, the pooled estimate of success rate was 59% (95% CI 50-68%), with low heterogeneity (I² = 30%). The technical failure and complication rates were 5% and 15%, respectively, but these variables had moderate heterogeneity. In 36 patients with individual patient data, a non-communicating type of hydrocephalus on imaging was associated with an odds ratio of 5.90 (95% CI 1.1-32.9, p = 0.043) for success. In summary, ETV for TBM had a pooled success rate of 59%, technical failure rate of 5%, and complication rate of 15%. An imaging finding of non-communicating hydrocephalus was associated with increased success. High-quality randomized, prospective studies using VPS insertion as control are needed to further define the role of ETV in TBM.

Complex hydrocephalus (combination of communicating and obstructive type): an important cause of failed endoscopic third ventriculostomy

Background

Hydrocephalus can be classified as purely obstructive, purely communicating or due to combinations of pathologies (obstruction in addition to defective absorption). Endoscopic third ventriculostomy (ETV) as an alternative to shunt procedures is an established treatment for obstructive hydrocephalus. However, patients who have combination of pathologies (complex hydrocephalus) could result in failure of ETV in spite of a patent stoma. The aim of this study was to prospectively evaluate the incidence of complex hydrocephalus in patients with obstructive hydrocephalus who failed an endoscopic third ventriculostomy.

Findings

Seventy one patients of obstructive hydrocephalus who underwent ETV in our institution were included in this study. Aetiology of hydrocephalus included congenital aqueductal stenosis in 42 and tubercular meningitis (TBM) in 29 patients. Failure of ETV was seen in 15 (21%) patients. These 15 patients included 6 (14.3%) from the congenital group and 9 (31.0%) patients from the TBM group. Iohexol CT ventriculography confirmed a patent stoma (suggesting a complex hydrocephalus) in 10 (66.7%) out of the 15 failed ETV cases. The incidence of complex hydrocephalus was more common in TBM group (8/29 patients, 27.60%) compared to congenital group (2/42 patients, 4.8%). The complex hydrocephalus patients with a patent ETV stoma were successfully managed by a lumbar peritoneal (LP) shunt.

Conclusion

Ten out of the 71 patients (14%) with obstructive hydrocephalus who underwent an ETV had a complex hydrocephalus, which was the major (66.7%) cause for failure of ETV. Improving methods to detect the exact type of hydrocephalus pre-operatively could increase success rate of ETV and avoid an unnecessary operative procedure (ETV).