Factors affecting the outcome of neuroendoscopy in patients with tuberculous meningitis hydrocephalus: a preliminary study

Comparison of ventriculoperitoneal shunt versus endoscopic third ventriculostomy in managing hydrocephalus due to tuberculous meningitis: a randomized controlled trial with a 30-day follow-up

Background

Hydrocephalus is a significant complication arising from tuberculous meningitis (TBM). While ventriculoperitoneal shunt (VPS) remains the primary surgical approach for TBM-related hydrocephalus, there is a rising trend in the use of endoscopic third ventriculostomy (ETV).

Materials and methods

This randomized controlled trial, conducted from February 2018 to July 2019, enroled 60 patients aged 20-50 with TBM-related hydrocephalus. Patients underwent either VPS or ETV. Both groups were followed up for a minimum of 30 days, evaluating clinical outcomes and modifications in the modified Vellore grading system. Glasgow Coma Scale (GCS) assessments were conducted at 7-days and 30-day post-surgery for both groups.

Results

The mean GCS scores were comparable between the two groups on the 7th and 30th postoperative days. The association between modified Vellore Grade and treatment modality did not show statistically significant differences (P=1.0 and P=0.3) on the seventh and thirtieth postoperative days respectively.

Conclusions

Both VPS and ETV demonstrate efficacy in managing hydrocephalus secondary to TBM in adult patients. Our 30-day outcomes did not reveal discernible differences between the two procedures. Therefore, considering technical expertise and experience with ETV, it may be considered as the primary choice for cerebrospinal fluid (CSF) diversion in TBM-associated hydrocephalus, owing to its avoidance of several lifelong complications linked with VPS.

Rigid versus flexible neuroendoscopy: a systematic review and meta-analysis of endoscopic third ventriculostomy for the management of pediatric hydrocephalus

OBJECTIVE

Endoscopic third ventriculostomy (ETV), with or without choroid plexus cauterization (±CPC), is a technique used for the treatment of pediatric hydrocephalus. Rigid or flexible neuroendoscopy can be used, but few studies directly compare the two techniques. Here, the authors sought to compare these methods in treating pediatric hydrocephalus.

METHODS

A systematic MEDLINE search was conducted using combinations of keywords: "flexible," "rigid," "endoscope/endoscopic," "ETV," and "hydrocephalus." Inclusion criteria were as follows: English-language studies with patients 2 years of age and younger who had undergone ETV±CPC using rigid or flexible endoscopy for hydrocephalus. The primary outcome was ETV success (i.e., without the need for further CSF diversion procedures). Secondary outcomes included ETV-related and other complications. Statistical significance was determined via independent t-tests and Mood's median tests.

RESULTS

Forty-eight articles met the study inclusion criteria: 37 involving rigid endoscopy, 10 involving flexible endoscopy, and 1 propensity scored-matched comparison. A cumulative 560 patients had undergone 578 rigid ETV±CPC, and 661 patients had undergone 672 flexible ETV±CPC. The flexible endoscopy cohort had a significantly lower average age at the time of the procedure (0.33 vs 0.53 years, p = 0.001) and a lower preoperatively predicted ETV success score (median 40, IQR 32.5-57.5 vs 62.5, IQR 50-70; p = 0.033). Average ETV success rates in the rigid versus flexible groups were 54.98% and 59.65% (p = 0.63), respectively. ETV-related complication rates did not differ significantly at 0.63% for flexible endoscopy and 3.46% for rigid endoscopy (p = 0.30). There was no significant difference in ETV success or complication rate in comparing ETV, ETV+CPC, and ETV with other concurrent procedures.

CONCLUSIONS

Despite the lower expected ETV success scores for patients treated with flexible endoscopy, the authors found similar ETV success and complication rates for ETV±CPC with flexible versus rigid endoscopy, as reported in the literature. Further direct comparison between the techniques is necessary.

Role of Surgical Procedures (VP Shunt and ETV) in Tuberculous Meningitis with Hydrocephalus (TBMH): A Systematic Review

Objective

Hydrocephalus is one of the most common complications of tuberculous meningitis. Various cerebrospinal fluid diversion procedures, endoscopic third ventriculostomy (ETV) and shunt surgery, are performed for the management of the hydrocephalus associated with tuberculous bacterial meningitis (TBM). There is decreased clarity on the type of procedure to be done. So, this study aims at generating knowledge to understand the conditions in which either of the two procedures, ETV and shunt surgery, is a better option and to develop good practice guidelines for the treatment of tubercular meningitis hydrocephalus (TBMH).

Materials and Methods

A systematic search of literature was performed by using PubMed and Cochrane Central Register of Controlled Trials (CENTRAL) for articles published from January 2001 to April 2020. A total of 15 studies were included irrespective of their design and having diagnosis with TBMH treated with ventriculoperitoneal shunt surgery (VPS) or ETV. Then, a systemic review was done regarding outcomes, complications, and recommendations made in different studies.

Results

The total number of patients diagnosed with TBMH was 603; among them, 348 patients had VPS and 255 patients had ETV. In the VPS group, the patient's good outcome varied from 25% to 68% and complication rate ranged from 10% to 43.8%. The average percentage of good outcome in the VPS group was 51.8%. In the ETV group, the patient's good outcome varied from 41% to 77% and complication rate ranged from 10% to 23.5%. The average percentage of good outcome in the ETV group was 68%. There was a significant difference in the average percentage of good outcome in the ETV versus the VPS shunt group (P-value was 0.008).

Conclusion

There was a significant difference in the average percentage of good outcome after ETV than VPS, and complication rate was also slightly lower after ETV than VPS during the chronic phase of illness. So during the acute phase of illness VPS placement is preferred whereas in the chronic burnout phase ETV is preferred because poor anatomy leads to more complications with ETV during the acute phase of the disease.

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.

Endoscopic Treatment of Hydrocephalus with Minimal Resources: Resource Utilization and Indigenous Innovation in Developing Countries like India

CONTEXT

Neuroendoscopic surgeries need specialized equipments, unavailable in neurosurgical departments of majority of public healthcare institutions of India. Aims: Neuroendoscopic treatment of hydrocephalus in the setting of minimal resources using utilization of available resources, inter-departmental co-ordination and indigenous innovations.

METHODS

Study was carried out at a public sector institute of India with scarce resources. Senior author (DKJ) used indigenously designed stainless steel working sheath along with equipments of 'awake endoscopic intubation system' of department of neuroanesthesia and 18 cm, 4 mm, 0° rigid telescope for neuroendoscopic surgeries for various intraventricular pathologies.

RESULTS

Thirty-four neuroendoscopic surgeries in 32 patients were done over last 3 years. There were 18 males and 14 females with average age of 23 years. It included hydrocephalus due to tubercular meningitis (n = 19), neurocysticercosis (NCC) (n = 4), intra-ventricular (n = 2) and para-ventricular (n = 2) space occupying lesions, aqueduct stenosis with (n = 2) or without (n = 1) shunt malfunction and one case each of pyogenic meningitis and right cerebellar infarction. Endoscopic third ventriculostomy (ETV) (n = 28), septostomy (n = 6), removals of cystic lesions (n = 3) and biopsies of intraventricular lesions (n = 2) were done in a total of 34 neuroendoscopic surgeries. Overall there were four failures of ETVs, which were managed by ventriculo-peritoneal shunts. Two mortalities in the study group were unrelated to the surgical procedures.

CONCLUSION

Indigenous innovations and interdisciplinary co-ordination are the way ahead to tackle resource scarcity in public sector healthcare institutions of India in the scenario of plenty of neuroendoscopic trainings opportunities for young neurosurgeons and paucity of equipments required.

A Randomized Study Comparing Endoscopic Third Ventriculostomy versus Ventriculoperitoneal Shunt in the Management of Hydrocephalus Due to Tuberculous Meningitis

Objectives

The objective of this study was to compare safety and efficacy of endoscopic third ventriculostomy (ETV) versus ventriculoperitoneal (VP) shunt in the treatment of hydrocephalus in tuberculous meningitis (TBM) and to assess clinical and radiological profiles of patients with TBM that would be better suited to either VP shunt or ETV.

Methods

This study was a single-center randomized prospective study on 52 patients with TBM hydrocephalus in the pediatric age group (<18 years of age). Patients included in the study were randomized into undergo either VP shunt or ETV. Both groups were followed up for a minimum of 5 months and assessed for success and failure rates as well as procedural complications and neurologic sequelae.

Results

Twenty-six patients underwent ETV with a success rate of 65.4% with six of nine failures occurring within the first 16 days after surgery (median time to failure - 3 days). In the VP shunt group, there was a success rate of 61.54% and a median time to failure of 50 days. Modified Vellore grading was found to be a significant factor in determining outcome in both ETV and VP shunt groups with high-grade TBM consistently associated with poor outcome (odds ratio = 4.2).

Conclusions

ETV can be performed effectively in young children including infants, as well as those with communicating hydrocephalus, high cerebrospinal fluid (CSF) cell counts, and protein levels with a lower rate of failure than that of VP shunt. Hence, ETV should be attempted as the first-choice CSF diversion procedure in hydrocephalus secondary to TBM where technical expertise and experience with this procedure is available as it avoids the myriad of lifelong complications associated with shunts.

Role of endoscopic third ventriculostomy in tuberculous meningitis with hydrocephalus

Hydrocephalus is one of the commonest complications of tuberculous meningitis (TBM). It can be purely obstructive, purely communicating, or due to combinations of obstruction in addition to defective absorption of cerebrospinal fluid (CSF). Endoscopic third ventriculostomy (ETV) as an alternative to shunt procedures is an established treatment for obstructive hydrocephalus in TBM. ETV in TBM hydrocephalus can be technically very difficult, especially in acute stage of disease due to inflamed, thick, and opaque third ventricle floor. Water jet dissection can be helpful in thick and opaque ventricular floor patients, while simple blunt perforation is possible in thin and transparent floor. Lumbar peritoneal shunt is a better option for communicating hydrocephalus as compared to VP shunt or ETV. Intraoperative Doppler or neuronavigation can help in proper planning of the perforation to prevent neurovascular complications. Choroid plexus coagulation with ETV can improve success rate in infants. Results of ETV are better in good grade patients. Poor results are observed in cisternal exudates, thick and opaque third ventricle floor, acute phase, malnourished patients as compared to patients without cisternal exudates, thin and transparent third ventricle floor, chronic phase, well-nourished patients. Some of the patients, especially in poor grade, can show delayed recovery. Failure to improve after ETV can be due to blocked stoma, complex hydrocephalus, or vascular compromise. Repeated lumbar puncture can help faster normalization of the raised intracranial pressure after ETV in patients with temporary defect in CSF absorption, whereas lumbar peritoneal shunt is required in permanent defect. Repeat ETV is recommended if the stoma is blocked. ETV should be considered as treatment of choice in chronic phase of the disease in obstructive hydrocephalus.

Surgery for brain tuberculosis: a review

The two main manifestations of brain tuberculosis that require surgery are hydrocephalus associated with tuberculous meningitis (TBMH) and brain tuberculomas. TBMH most often responds to medical therapy but surgery is required promptly for those who fail medical therapy. Both ventriculoperitoneal (VP) shunt and endoscopic third ventriculostomy (ETV) are valid options although the latter is more often successful in patients with chronic hydrocephalus than in those with acute meningitis. Patients with TBMH are more prone to complications following VP shunt than other patients. The outcome of these patients is determined by the Vellore grade (I to IV) of the patients prior to surgery with those in good grades (I and II) having a better outcome and those in the worst grade (IV) having a high mortality in excess of 80 %. Patients with brain tuberculomas present clinically with features of a brain mass, indistinguishable clinically from other pathologies. CT and MR features might provide a probable diagnosis of a tuberculoma but most often a histological diagnosis is desirable. Empiric medical therapy is reserved for a small number of patients. Although the treatment of brain tuberculomas is essentially medical, surgery is required when the diagnosis is in doubt, to reduce raised intracranial pressure or local mass effect and to obtain tissue for culture and sensitivity studies. Stereotactic biopsy, stereotactic craniotomy and excision of superficial small tuberculomas and microsurgery are all procedures used to manage brain tuberculomas. The outcome in patients with brain tuberculomas is good if the tuberculous bacillus is sensitive to the anti-tuberculous therapy. The duration of therapy is debated but we suggest at least 18 months of combination therapy with three or four anti-tuberculous drugs and continue the therapy till the tuberculoma has resolved on neuro-imaging.

Infektionen

In diesem Kapitel werden zunächst die für die Neurointensivmedizin wesentlichen bakteriellen Infektionen (Meningitis, spinale und Hirnabszesse, Spondylodiszitis, septisch-embolische Herdenzephalitis) abgehandelt, die trotz gezielt eingesetzter Antibiotika und neurochirurgischer Therapieoptionen noch mit einer erheblichen Morbidität und Mortalität behaftet sind. Besonderheiten wie neurovaskuläre Komplikationen, die Tuberkulose des Nervensystems, Neuroborreliose, Neurosyphilis und opportunistische Infektionen bei Immunsuppressionszuständen finden hierbei besondere Berücksichtigung. Der zweite Teil dieses Kapitels behandelt akute und chronische Virusinfektionen des ZNS sowie in einem gesonderten Abschnitt die HIVInfektion und HIV-assoziierte Krankheitsbilder sowie Parasitosen und Pilzinfektionen, die in Industrieländern seit Einführung der HAART bei HIV zwar eher seltener, aber mit zunehmender Globalisierung auch in unseren Breiten immer noch anzutreffen sind.

[Treatment of intractable tuberculous meningitis using intrathecal isoniazid administration and steroid pulse therapy; a report of two cases]

Tuberculous meningitis (TbM) is a neurological emergency condition that requires prompt initiation of treatment. The standard initial treatment for TbM is often insufficient for producing remission because the anti-tuberculosis agent may cause severe side effects, or vasculitis and hydrocephalus may induce an intractable state. Moreover, it is difficult to distinguish paradoxical expansion from its own deterioration. We treated 2 cases of adult TbM by using multidisciplinary therapy, including methyl prednisolone pulse and intrathecal isoniazid administration. Both cases had not been diagnosed as pulmonary or other tuberculosis, and cerebrospinal fluid (CSF) culture and polymerase chain reaction at approximately 1 week after hospitalization identified the cases as TbM. We administered the standard initial treatment recommended by the British Infection Society guidelines for adults, but both cases deteriorated and showed elevation of intracranial pressure. We indwelled a lumbar drainage for Case 1 and an Ommaya reservoir for Case 2. We removed CSF and administrated isoniazid regularly using each of the drainage devices, added streptomycin, and increased the steroid dose including addition of steroid pulse therapy. Both cases improved, and their neurological dysfunction did not persist. After the induction of an intractable state occurs due to TbM, we are likely to assume poor prognosis and neurological sequelae. However, our experience in these cases showed amelioration of the symptoms leading to the rehabilitation of these patients in society.

Tuberculous meningitis

Tuberculous (TB) meningitis is common in resource-poor communities but also occurs in developed countries where the diagnosis is frequently delayed because of unfamiliarity with the disease. TB meningitis develops whenever a small intracranial tuberculoma (Rich focus) ruptures causing predominantly basal meningitis. This results in hydrocephalus, cranial nerve palsies, and ischemic brain injury secondary to tuberculous vasculitis. The primary source of TB is usually the lung. Early diagnosis is difficult because patients tend to present subacutely with nonspecific symptoms such as fever, cough, vomiting, listlessness, and failure to thrive. Lumbar puncture typically shows clear and colorless CSF with a low, predominantly lymphocytic, leukocytosis and raised protein and low glucose levels. Decision to treat is mostly clinical because of difficulty in demonstrating TB bacilli on routine smear and time needed for culture. A positive TB contact, Mantoux skin test, chest radiograph, CT/MRI brain scan, PCR for tuberculosis on CSF, and demonstration of TB bacilli from extraneural sources are invaluable in supporting a diagnosis of TB meningitis. Current World Health Organization guidelines recommend treatment with a four-drug regimen for 2 months, followed by a two-drug regimen for 10 months, the total duration of treatment being 12 months. Corticosteroids reduce mortality without changing neurological morbidity. Outcome relates closely to age and stage of disease.

Effects of the implantation of Ommaya reservoir in children with tuberculous meningitis hydrocephalus: a preliminary study

OBJECTIVE

The role of Ommaya reservoir implantation in children with tuberculous meningitis hydrocephalus (TBMH) has been seldomly reported. Therefore, we performed this study to determine the role of the Ommaya reservoir in the treatment of children with TBMH.

METHODS

We retrospectively analyzed the effects of Ommaya reservoir implantation in 12 children with TBMH. Intracapsular puncture of the reservoir was performed for draining the cerebrospinal fluid and the TBM was treated by intraventricular injection of isoniazid.

RESULTS

The ideal treatment outcome was observed in nine (75 %) of the 12 children; two (16.7 %) children developed serious disabilities and one of them (8.3 %) eventually died. The treatment method was effective for all six (100 %) children with Palur grade II TBM but showed no effect in three (50 %) children with grade III and IV TBM. The number of leukocytes in the cerebrospinal fluid decreased to 20 × 10(6)/L (75 %) within 2 weeks after implantation of the reservoirs. Finally, the Ommaya reservoirs in eight children were removed but were retained in four children. Four children had to undergo ventriculoperitoneal shunt.

CONCLUSION

Ommaya reservoir implantation has been shown to be effective in treating children with TBMH. This method may be largely suitable for children with early grade II TBM or partly in children with grade III TBM who have mild or moderate hydrocephalus that can alleviate after short-term treatment. Thus, a good proportion of children who undergo Ommaya reservoir implantation can avoid ventriculoperitoneal shunt surgery.

Endoscopic observations of blocked ventriculoperitoneal (VP) shunt: a step toward better understanding of shunt obstruction and its removal

OBJECTIVES

Most of our understanding of ventriculoperitoneal (VP) shunt blockage (ventricular end) is based on in vitro studies of blocked VP shunts. Not much information is available regarding the in vivo changes that occur in the tube and in the surrounding ventricle. The primary aim of our study was to observe and analyse these changes, directly, through the endoscope, in patients with blocked shunts undergoing an endoscopic third ventriculostomy (ETV). Based on these findings, we have also suggested criteria for safe removal of the VP shunt tube following ETV.

MATERIAL AND METHODS

ETV was performed with standard technique in patients with blocked VP shunt. The ventricular end of the shunt tube was inspected through the endoscope, for changes in ventricle linings as well as in the shunt tube. These changes were correlated with the age of the patient, etiology of HC, type or make of the shunt tube, duration of shunt placement to ETV and the CSF findings.

RESULTS

Fifty-three patients of blocked VP shunt underwent ETV from July 2006 to April 2010. Thirty patients had Chhabra (CH) V P Shunt (Surgiwear, India) and 23 had ceredrain (CD) shunt (Hindustan Latex, India). The age of the patients ranged from 2 months to 60 years (mean--13.33 years.). Various causes of hydrocephalus (HC) included congenital hydrocephalus (aqueductal stenosis) in 18 patients, post-meningitis hydrocephalus (PMH) in 32 cases, neuro-cysticercosis (NCC) in 2 patients and intraventricular haemorrhagic (IVH) in 1 patient. Clinical and radiological improvement occurred in 33 (62.21%), and 24 (45%) patients, respectively. Freedom from shunt was attained in 20 (38%) patients. The changes around the shunt tube were seen in 41 (77%). Hyperaemia and neovascularised ependyma was seen in 20 (37%) and 15 (28%) patients. Encasement of the tube was seen in 41%. Ependymal growth and neovascularised shunt tubes were noticed in 15% each. Choroid plexus blocking the tube was seen in only four cases (7%). VP shunt was revised in 14 patients (26.4%). Patient with infective etiology had more changes (p < 0.005). Age, CSF findings and make of shunt tube had no relation with endoscopic observations (p< 0.02).

CONCLUSIONS

ETV has a role in shunt failures. It can offer patient a chance of shunt free life. Endoscopic observation of shunt tube and ventricle can unfold several interesting in vivo findings pertaining to shunt obstruction. Shunt should only be removed if there are no adhesions and neovascularisation.

Role of ventriculoperitoneal shunt surgery in grade IV tubercular meningitis with hydrocephalus

PURPOSE

Hydrocephalus is a common complication of tuberculous meningitis (TBM) in children. The role of ventriculoperitoneal shunt (VPS) placement in grade IV patients is controversial. The aim of this study is to investigate the clinical value of VPS placement for patients with grade IV TBM with hydrocephalus (TBMH).

METHODS

This study was carried out on children with grade IV TBMH from January 2006 to January 2011 in Xiangya Hospital, China. All patients were given VPS placement combined with medicine treatment. External ventricular drainage (EVD) was performed only in the presence of severe biochemical derangements or brainstem dysfunction requiring correction before shunt surgery. Outcomes were divided into normal, mild sequelae, severe sequelae, death, or vegetable status.

RESULTS

A total of 19 children with grade IV TBMH were recruited into the study. The average follow-up period was 29 months. Three of the 19 patients expired, four patients had a full recovery, eight had slight sequelae, and four had severe sequelae. Six complications related to the shunt surgery were seen among the patients.

CONCLUSIONS

This study demonstrates that direct ventriculoperitoneal shunt surgery could improve the outcome of grade IV TBMH. The response to EVD is not a reliable indication for selecting patients who would benefit from shunt surgery.

Infektionen

Trotz Weiterentwicklung moderner Antibiotika in den letzten Jahren sind die Letalitätszahlen der bakteriellen (eitrigen) Meningitis weiterhin hoch; Überlebende haben häufig neurologische Residuen. Die ungünstigen klinischen Verläufe der bakteriellen Meningitis sind meist Folge intrakranieller Komplikationen, wie z. B. eines generalisierten Hirnödems, einer zerebrovaskulären arteriellen oder venösen Beteiligung oder eines Hydrozephalus.

Overview of post-infective hydrocephalus

INTRODUCTION

Post-infective hydrocephalus refers to accumulation of fluid within the cranial cavity (hydrocephalus) secondary to either pyogenic or tuberculous meningitis. Whereas in the former condition, fibrous adhesions develop in the ventricles and arachnoid villi, in the latter, the fibrosis is mainly basal.

METHODS

This is a review of the author's personal series as well as published literature on post-infective hydrocephalus.

CONCLUSION

The aim of treatment in hydrocephalus following pyogenic meningitis is to sterilize the cerebrospinal fluid (CSF) and then to drain the ventricles after conversion of a multiloculated cavity into a single cavity. In hydrocephalus associated with tuberculous meningitis, CSF diversion is not always necessary and should be reserved for cases where clinical deterioration occurs pari passu with increase in ventricular size and intraventricular pressure.

HIV-associated tuberculous meningitis--diagnostic and therapeutic challenges

HIV-associated tuberculous meningitis (TBM) poses significant diagnostic and therapeutic challenges and carries a dismal prognosis. In this review, we present the clinical features and management of HIV-associated TBM, and compare this to disease in HIV-uninfected individuals. Although the clinical presentation, laboratory findings and radiological features of TBM are similar in HIV-infected and HIV-uninfected patients, some important differences exist. HIV-infected patients present more frequently with extra-meningeal tuberculosis and systemic features of HIV infection. In HIV-associated TBM, clinical course and outcome are influenced by profound immunosuppression at presentation, emphasising the need for earlier diagnosis of HIV infection and initiation of antiretroviral treatment.

Minimally invasive neurosurgery for cerebrospinal fluid disorders

This article focuses on minimally invasive approaches used to address disorders of cerebrospinal fluid (CSF) circulation. The author covers the primary CSF disorders that are amenable to minimally invasive treatment, including aqueductal stenosis, fourth ventricular outlet obstruction (including Chiari malformation), isolated lateral ventricle, isolated fourth ventricle, multiloculated hydrocephalus, arachnoid cysts, and tumors that block CSF flow. General approaches to evaluating disorders of CSF circulation, including detailed imaging studies, are discussed. Approaches to minimally invasive management of such disorders are described in general, and for each specific entity. For each procedure, indications, surgical technique, and known outcomes are detailed. Specific complications as well as strategies for their avoidance and management are addressed. Lastly, future directions and the need for structured outcome studies are discussed.

Tuberculous meningitis

Tuberculous meningitis is a severe form of extrapulmonary tuberculosis. The exact incidence and prevalence are not known. In countries with high burden of pulmonary tuberculosis, the incidence is expected to be proportionately high. Children are much more vulnerable. Human immunodeficiency virus-infected patients have a high incidence of tuberculous meningitis. The hallmark pathological processes are meningeal inflammation, basal exudates, vasculitis and hydrocephalus. Headache, vomiting, meningeal signs, focal deficits, vision loss, cranial nerve palsies and raised intracranial pressure are dominant clinical features. Diagnosis is based on the characteristic clinical picture, neuroimaging abnormalities and cerebrospinal fluid changes (increased protein, low glucose and mononuclear cell pleocytosis). Cerebrospinal fluid smear examination, mycobacterial culture or polymerase chain reaction is mandatory for bacteriological confirmation. The mortality and morbidity of tuberculous meningitis are exceptionally high. Prompt diagnosis and early treatment are crucial. Decision to start antituberculous treatment is often empirical. WHO guidelines recommend a 6 months course of antituberculous treatment; however, other guidelines recommend a prolonged treatment extended to 9 or 12 months. Corticosteroids reduce the number of deaths. Resistance to antituberculous drugs is associated with a high mortality. Patients with hydrocephalus may need ventriculo-peritoneal shunting. Bacillus Calmette-Guérin vaccination protects to some degree against tuberculous meningitis in children.

Update on tuberculosis of the central nervous system: pathogenesis, diagnosis, and treatment

Tuberculous meningitis is the most dangerous form of tuberculosis, yet our understanding of disease pathogenesis is based upon studies performed in the 1920s, our diagnostic methods are dependent upon those developed in the 1880 s, and our treatment has advanced little since the introduction of isoniazid in the 1950s. The authors focus this review on three important questions. First, how does Mycobacterium tuberculosis reach the brain? Second, what is the best way of identifying patients who require early empiric antituberculosis therapy? Third, what is the best way of managing tuberculous hydrocephalus?

British Infection Society guidelines for the diagnosis and treatment of tuberculosis of the central nervous system in adults and children

SUMMARY AND KEY RECOMMENDATIONS: The aim of these guidelines is to describe a practical but evidence-based approach to the diagnosis and treatment of central nervous system tuberculosis in children and adults. We have presented guidance on tuberculous meningitis (TBM), intra-cerebral tuberculoma without meningitis, and tuberculosis affecting the spinal cord. Our key recommendations are as follows: 1. TBM is a medical emergency. Treatment delay is strongly associated with death and empirical anti-tuberculosis therapy should be started promptly in all patients in whom the diagnosis of TBM is suspected. Do not wait for microbiological or molecular diagnostic confirmation. 2. The diagnosis of TBM is best made with lumbar puncture and examination of the cerebrospinal fluid (CSF). Suspect TBM if there is a CSF leucocytosis (predominantly lymphocytes), the CSF protein is raised, and the CSF:plasma glucose is <50%. The diagnostic yield of CSF microscopy and culture for Mycobacterium tuberculosis increases with the volume of CSF submitted; repeat the lumbar puncture if the diagnosis remains uncertain. 3. Imaging is essential for the diagnosis of cerebral tuberculoma and tuberculosis involving the spinal cord, although the radiological appearances do not confirm the diagnosis. A tissue diagnosis (by histopathology and mycobacterial culture) should be attempted whenever possible, either by biopsy of the lesion itself, or through diagnostic sampling from extra-neural sites of disease e.g. lung, gastric fluid, lymph nodes, liver, bone marrow. 4. Treatment for all forms of CNS tuberculosis should consist of 4 drugs (isoniazid, rifampicin, pyrazinamide, ethambutol) for 2 months followed by 2 drugs (isoniazid, rifampicin) for at least 10 months. Adjunctive corticosteroids (either dexamethasone or prednisolone) should be given to all patients with TBM, regardless of disease severity. 5. Children with CNS tuberculosis should ideally be managed by a paediatrician with familiarity and expertise in paediatric tuberculosis or otherwise with input from a paediatric infectious diseases unit. The Children's HIV Association of UK and Ireland (CHIVA) provide further guidance on the management of HIV-infected children (www.chiva.org.uk). 6. All patients with suspected or proven tuberculosis should be offered testing for HIV infection. The principles of CNS tuberculosis diagnosis and treatment are the same for HIV infected and uninfected individuals, although HIV infection broadens the differential diagnosis and anti-retroviral treatment complicates management. Tuberculosis in HIV infected patients should be managed either within specialist units by physicians with expertise in both HIV and tuberculosis, or in a combined approach between HIV and tuberculosis experts. The co-administration of anti-retroviral and anti-tuberculosis drugs should follow guidance issued by the British HIV association (www.bhiva.org).