Preparation for Management of Tuberculosis of the Central Nervous System in Children
Indications for Management
Most can be managed medically: Patients with TB meningitis, tuberculomas, or abscesses without focal deficits and with a GCS of 15 can usually be managed medically.
Worsening neurological condition or poor response to medical management: If focal deficits develop or the GCS deteriorates, or if the disease does not respond to medical treatment over time, then surgery is considered with antibiotics and steroids. The prior use of the combination of serial lumbar puncture, diuretics, and steroid therapy may suffice while the early response to chemotherapy is evaluated.
Brain abscesses: Rarely, tuberculomas coalesce and liquefy to cause tuberculous cerebral abscesses that may necessitate surgery. Early surgical drainage and chemotherapy are considered the most appropriate treatment for TB abscesses and can be therapeutic as well as diagnostic (24). Surgery should be carefully planned and individualized according to the patient’s clinical condition, anatomic localization, and number of lesions. Early anti-TB therapy must be considered in all cases of suspected TB abscess even before surgery to reduce the risk of postoperative meningitis. An open surgical excision is an appropriate treatment option for large, multiloculated cerebellar lesions that cause brain herniation and also for those that do not respond to aspiration, while stereotactic-guided aspiration is preferred in eloquent or deep-seated areas such as the hypothalamus, thalamus, or deep temporal regions to prevent severe neurological sequelae. The main disadvantages of the latter option are the need for repeated procedures in as many as 70% of patients and the high risk of rupture into ventricles or the subarachnoid space, which could lead to ventricular ependymitis or meningitis and worsening of neurological deficits. An early surgical procedure can improve the efficacy of anti-TB therapy, promote a better clinical response after reduction of bacillary load, and reduce mortality (43).
Spinal tuberculomas and abscesses: Spinal tuberculosis associated with paraparesis responds well to medical treatment (which may include corticosteroids) if the MRI shows relatively preserved cord size and edema with predominantly fluid compression. Patients with extradural compression by a tuberculoma or abscess, but with little fluid component compressing or constricting the cord, probably need early surgical decompression (3, 22, 44, 45).
Antibiotics: Anti-TB therapy helps to reduce the inflammatory response, leading to opening of the CSF pathways.
Steroids: See Adjuvant Therapies.
Diuretics: For individuals with communicating hydrocephalus, the addition of acetazolamide and furosemide to standard anti-TB therapy is superior to antibiotics alone. Mannitol can be used only for acute decompensation and is not recommended for more than 72 hours due to the occurrence of rebound intracranial hypertension. Acetazolamide (100 mg/kg) and furosemide (1 mg/kg) can be given for longer periods of up to 1 month. The addition of these drugs was significantly more effective in achieving normal ICP.
Lumbar puncture: For those with hydrocephalus and in poor health, serial LPs may be done to manage elevated ICPs and also document clinical improvement. Only those patients who improve are usually considered for definitive treatment of their hydrocephalus with a ventricular shunt. Follow-up serial LPs are also done on patients with TB meningitis to document changes occurring in the CSF during the course of treatment. Normalization of the CSF then serves to confirm the response to therapy (46).
CNS complications can complicate anesthesia: In management of CNS TB, potential complications include associated elevated ICP, hydrocephalus, vasculitis, acute seizures, fever, and hyponatremia. Aggressive and appropriate treatment of these complications can minimize the secondary brain injury and improve the chance of a good outcome. Associated pulmonary TB might have other considerations.
Devices to Be Implanted
No special devices: No special devices are needed. Routine devices as needed for shunt surgery or EVD placement are used.
Operating microscope: If a deep lesion or lesion close to eloquent tissue requires surgery, then an operating microscope can be considered for better illumination and visualization of the surgical field.
Intraoperative navigation: Real-time neuronavigation with high-quality 3D ultrasound, intraoperative ultrasound, and Stealth navigation have all been used in the surgical excision of lesions and the placement of a ventriculoperitoneal shunt. Neuromonitoring may be used for lesions in eloquent areas. ETV has also been used in patients with hydrocephalus with the hope that if a foreign body insertion could be avoided, the accompanying complications of a shunt (infection, blockage, extrusion, abdominal pseudocysts, skin erosion over shunt components) could also be avoided.