Diagnostic efficacy of stereotactic biopsies in intracranial tuberculomas

Intracranial giant tuberculoma: A 7-year institutional experience and literature review

BACKGROUND

Intracranial tuberculomas are infrequent with a lower morbidity and mortality compared to tubercular meningitis. Giant intracranial tuberculomas are rarer but important differentials for intracranial space-occupying lesions causing focal neurological deficits depending on anatomical location and size.

METHODS

Histopathologically confirmed giant intracranial tuberculomas selected based on institutional size criteria (<12 Years-old: ≥25 mm; 12-18 Years-old: ≥35 mm; ≥18 Years-old: ≥40 mm) were retrospectively reviewed and analyzed for clinical features, radiology, surgical management, and outcomes in patients admitted from 2015 to 2022.

RESULTS

Ten patients were included (Males:Females = 3:7; Age: 8-68 Years, Average: 30.1 Years). Mean duration of symptoms was 2.84 months. Two patients demonstrated active systemic tuberculosis. Previous tubercular infections included pulmonary involvement in four, meningeal in three, and a cerebellar tuberculoma in one patient. Cerebrospinal fluid analysis in five patients demonstrated no tubercle bacilli. Seven lesions were supratentorial and three infratentorial. Giant tuberculomas demonstrated profound T2 hypointensity, sub-marginal T2 hyperintense crescents, and significant perilesional vasogenic edema. Craniotomy and excision were mainstay except in one case treated only with ventriculoperitoneal shunting. Three additional patients underwent ventriculoperitoneal shunting for hydrocephalus. One patient died from aspiration pneumonia and sepsis following a postoperative seizure. Anti-Tubercular Therapy (ATT) was advised for 18 months. Follow up ranged from 4 to 18 months. One patient was medically managed for ATT-induced hepatitis, hepatic encephalopathy, and coincidental paradoxical reaction. Remainder of patients showed complete resolution of symptomatology and absence of new symptoms till latest follow up.

CONCLUSION

Clinical course of giant tuberculomas differ from non-giant variants in characteristic radiology, more intensive ATT, and possibility for partial debulking/excision.

Diagnostic and Neurological Overview of Brain Tuberculomas: A Review of Literature

Tuberculosis is a disease caused by a bacteria named Mycobacterium tuberculosis (M. tb). It is estimated by World Health Organization (WHO) that nearly a quarter of the world's population is infected. Tuberculoma of the brain is one of the most severe extrapulmonary forms that affects patients younger than 40 years of age. Brain parenchymal tuberculoma develops in nearly one of 300 non-treated cases of pulmonary tuberculosis cases. In endemic regions, tuberculomas account for as many as 50% of all intracranial masses. Tuberculoma results in a hematogenous spread of M. tb from an extracranial source. Tuberculomas can mimic a variety of diseases and can present themselves in a subacute or chronic course, from asymptomatic to severe intracranial hypertension. Diagnosis is based on computed tomography (CT) scan and magnetic resonance imaging (MRI) studies with a similar ring-enhancing lesion. Treatment is primarily medical, and the duration for brain tuberculoma can vary from six to 36 months. In certain cases, surgery is recommended.

What pulmonologists need to know about extrapulmonary tuberculosis

Extrapulmonary tuberculosis (EPT) can affect all organs. Its diagnosis is often challenging, especially when the lung is not involved. Some EPT locations, such as when the central nervous system is involved, are a medical emergency, and some have implications for treatment options and length. This review describes clinical features of EPT, diagnostic tests and treatment regimens.

Extrapulmonary tuberculosis can affect any organ, can be potentially life threatening or disabling, poses diagnostic difficulties and may change the type and length of treatment. Looking for concomitant pulmonary tuberculosis is essential.https://bit.ly/2YEaRVb

Isolated brainstem tuberculomas

BACKGROUND

Isolated brainstem tuberculomas are rare lesions and account for up to 5% of all intracranial tuberculomas in endemic areas. The difficulties in diagnosis and management of this condition are sparsely reported. The aim of this study is to illustrate the nuances in managing brainstem tuberculomas, define prognosis, and demonstrate a shift in management strategies with newer imaging modalities.

METHOD

A retrospective review of 14 patients diagnosed and treated with a diagnosis of 'isolated brainstem tuberculoma' between 2011 and 2015 was done. Diagnosis was made after combining the findings at clinical history, examination, as well as imaging features. Patients were treated with steroids for 6 weeks or until they made a meaningful clinical recovery, and antitubercular therapy (ATT) for a minimum of 18 months or until there was resolution of the tuberculoma. Confirmation of tubercular pathology was done by observing if response to treatment resulted in clinical improvement, which happened in all of our cases.

RESULTS

Mean age at diagnosis was 24.7 years and nine were males. Twelve patients had a combination of cranial nerve deficits with pyramidal weakness or sensory symptoms. Mean duration of symptoms was 4.7 months and tests for human immunodeficiency virus (HIV) infection were negative in all patients. Only two patients had a previous history of tubercular meningitis. Most lesions were located in the pons with size ranging from 1 to 22.2 cm³. Eight patients showed complete resolution of the lesion at latest follow-up and the rest were still on ATT. Mean duration of ATT received for resolution of the lesion was 22 months. Almost all of our patients improved clinically on steroids and ATT.

CONCLUSIONS

Intracranial tuberculomas may present with or without meningitis. A high index of suspicion is essential, especially in endemic areas. A combination of clinical symptoms, investigations, and imaging features help in coming to a diagnosis. Biopsy of a brainstem lesion is fraught with complications. Antitubercular therapy has a very good prognosis, though the duration of therapy required may be longer.

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.

[Extrapulmonary tuberculosis]

Each year, there are more than eight million new cases of tuberculosis and 1.3 million deaths. There is a renewed interest in extrapulmonary forms of tuberculosis as its relative frequency increases. Among extrapulmonary organs, pleura and lymph nodes are the most common. Their diagnosis is often difficult and is based on clinical, radiological, bacteriological and histological findings. Extrapulmonary lesions are paucibacillary and samplings, in most cases, difficult to obtain, so diagnosis is often simply presumptive. Nucleic acid amplification tests, which are fast and specific, have greatly facilitated the diagnosis of some forms of extrapulmonary tuberculosis. However, their sensitivity is poor and a negative test does not eliminate the diagnosis. Treatment is the same as for pulmonary forms, but its duration is nine to 12 months for central nervous system and for bone tuberculosis. Corticosteroids are indicated in meningeal and pericardial localizations. Complementary surgery is used for certain complicated forms.

Optochiasmatic tuberculoma as the sole manifestation of late recurrent tuberculosis

Brain tuberculomas account for 10-20% of space occupying brain lesions in developing countries. Most lesions are observed at time of tuberculosis diagnosis or soon after starting treatment. We herein describe a 32 year-old patient with a 14-month history of headache and progressive visual loss. Her past medical history revealed pulmonary tuberculosis treated eight years before. A brain MRI showed a T1- and T2-weighted isointense contrast-enhancing lesion in the optic chiasm. A presumptive diagnosis of optochiasmatic tuberculoma was made and isoniazid, rifampin, pyrazinamide, and ethambutol were started. Despite treatment, the patient evolved to blindness. The prompt recognition of this condition is extremely important since the presence of optochiasmal enhancement is associated with blindness in patients with tuberculosis.

Pathological features of intracranial germinomas with reference to fibrous tissue and granulomatous change

Intracranial germinomas are accompanied occasionally by a significant granulomatous change and abundant fibrous tissue, and this has made their pathological diagnosis difficult. However, the incidence of the granulomatous reaction and the presence of fibrous tissue together with their clinical characteristics in intracranial germinomas have not been fully investigated. Twenty-four germinomas, none of which had received preoperative treatment, were clinicopathologically examined. The location of the tumor was the pineal region (5 cases), the suprasellar region (13 cases), multiple lesions (2 cases), the basal ganglia region (1 case), and other regions (3 cases). Histologically, the germinomas could be divided into two types: (1) type A (18 cases) consisted mainly of large neoplastic cells and small lymphocytes, showing a two-cell pattern; (2) type B (6 cases) consisted predominantly of fibroinflammatory tissues containing occasional neoplastic cells (5/6 cases) and, rarely, neoplastic cells (1/6 cases). Perioperatively, two-cell-pattern germinomas (type A) were characterized as soft tumors and fibroinflammatory germinomas (type B) as hard tumors. Thus, the fibroinflammatory type B accounted for 25% of the intracranial germinomas. Although there were no topographical and clinical differences between the two types, we conclude that immunohistological studies to detect neoplastic germ cells are warranted in cases of small stereotactic biopsies of hard type B tumors.

THE SURGICAL MANAGEMENT OF INFECTIONS INVOLVING THE CEREBRUM

OBJECTIVE

Infection involving the cerebrum is a true neurosurgical emergency that requires rapid diagnosis and appropriate surgical and medical intervention to achieve good clinical outcome.

METHODS

Because of the potential for devastating neurological sequelae, it is imperative that neurosurgeons be involved in the diagnosis and management of these serious conditions once an infection is suspected. With the advent of computed tomography and magnetic resonance imaging, it is now possible to detect an infectious process early in its course and follow the response to therapy. Although significantly more effective than in the past, antimicrobial therapy alone is insufficient to eradicate most intracranial infections, especially in the presence of compression or displacement of the cerebrum. Surgery remains an essential part of the management of intracranial infection because of its ability to provide immediate relief from pressure on neural structures and thereby result in clinical improvement.

RESULTS

The most common infections affecting the brain, namely, cranial epidural abscess, subdural empyema, brain abscess, viral infection, tuberculosis, and neurocysticercosis, can each be associated with significant mass effect on the cerebrum that is greatly reduced through surgery. This relief, in combination with newer antimicrobial agents that have an improved ability to cross the blood brain barrier, has led to a reduction in the infection-related morbidity and mortality rates associated with intracranial infections.

CONCLUSION

Combining advanced imaging and surgical techniques in the form of intraoperative magnetic resonance image-guided neurosurgery may further enhance clinical outcomes in these once uniformly fatal diseases.

Endoscopic options in management of posterior third ventricular tumors

OBJECTIVE

A spectrum of both radiosensitive and radio-resistant lesions occurs in the region of the posterior third ventricle (PTV). Most of these are associated with hydrocephalus requiring a cerebrospinal fluid diversion procedure. The present study aims to assess the effectiveness of endoscopic biopsy and third ventriculostomy (ETV) in these patients.

MATERIALS AND METHODS

Twenty-four patients with PTV lesions with moderate to severe hydrocephalus were managed prospectively. All patients underwent ETV and biopsy of the lesion during the same procedure. The ETV could be performed in all patients, where as in 23, a successful biopsy could be obtained. The ETV was successful in 22 patients; it failed in 2 patients requiring shunt insertion. A positive biopsy was obtained in all the patients (pinealocytoma 4, pinealoblastoma 10, embryonal cell carcinoma 1, germinoma 2, oligodendroglioma 1, astrocytoma 2, tuberculoma 4). All patients were subsequently managed with further surgery, radiation, and chemotherapy either alone or in combination depending on the pathology. One patient with a tumor bed hematoma required clot evacuation. The follow-up period ranged from 12 to 36 months. Two patients died, one during hospital stay with a tumor bed hematoma and another at 6 months follow-up due to extensive leptomeningeal spread.

CONCLUSIONS

The high yield of endoscopic biopsy (100%) and success of ETV (91%) emphasizes its role in management of the diverse group of PTV lesions in arriving at the optimal definitive management.

Intracranial tuberculomas developing while on therapy for pulmonary tuberculosis

We describe the case of a south Asian man who developed symptomatic intracranial tuberculomas while on therapy for pulmonary tuberculosis. The development or progression of intracranial tuberculomas during the course of appropriate antituberculous therapy has been recognised previously. We review the epidemiology, pathophysiology, diagnosis, and treatment of this paradoxical phenomenon. Although the aetiology of this reaction is unknown, it may be related to an enhanced immune response during the course of therapy. Routine brain imaging for all patients diagnosed with tuberculosis is not recommended; however, in patients presenting with new neurological findings, neuroimaging is clearly warranted. Stereotactic brain biopsy should be done whenever the diagnosis of an intracranial tuberculoma is in doubt. When intracranial tuberculomas become symptomatic, antituberculous therapy generally does not need to be changed. Corticosteroids are indicated in all symptomatic cases.

Tuberculoma Mimicking Falx Meningioma-Case Report-

A 25-year-old male presented with an intracranial tuberculoma mimicking falx meningioma manifesting as right lower monoparesis. The patient had a past history of pulmonary tuberculosis, cured by antituberculous therapy. Computed tomography and magnetic resonance (MR) imaging showed a lesion mimicking a falx meningioma. Surgery achieved subtotal resection. Histological and biochemical examinations revealed the surgical specimen was tuberculoma. He was treated with antituberculous therapy, and his gait disturbance disappeared. Follow-up MR imaging showed no regrowth.