A brain abscess is a focal intracranial infection characterized by a localized collection of pus within the brain parenchyma, resulting from bacterial, fungal, or parasitic infection. It represents a serious neurosurgical condition due to its potential for rapid neurological deterioration, raised intracranial pressure, and life-threatening complications. Brain abscesses may arise through contiguous spread from adjacent structures, hematogenous dissemination from distant infection sites, or direct inoculation following trauma or surgery.

Clinical presentation is often subacute and may vary depending on abscess location, size, and rate of progression. Common symptoms include headache, fever, altered mental status, seizures, and focal neurological deficits. Signs of raised intracranial pressure such as vomiting or papilledema may be present in larger lesions. Immunocompromised patients may present atypically, with minimal systemic signs of infection, increasing diagnostic complexity.

Neurosurgical evaluation relies heavily on neuroimaging. Magnetic resonance imaging with contrast typically demonstrates a ring-enhancing lesion with surrounding edema, although differentiation from neoplasm or metastasis may be challenging. Diffusion-weighted imaging plays a critical role in diagnosis by identifying restricted diffusion characteristic of abscess content. Accurate diagnosis is essential to guide timely surgical and medical management.

Management of brain abscess requires a combined neurosurgical and infectious disease approach. Surgical intervention is indicated in selected cases, particularly when abscesses are large, causing mass effect, associated with neurological deterioration, or refractory to medical therapy. Surgical objectives include decompression, reduction of intracranial pressure, microbiological diagnosis, and prevention of rupture into the ventricular system.

Surgical techniques include stereotactic aspiration or open craniotomy depending on abscess location, accessibility, and clinical urgency. The goal is maximal infection control with minimal disruption of surrounding brain tissue. Intraoperative sampling guides targeted antimicrobial therapy, which is continued for an extended duration postoperatively.

Postoperative management involves close neurological monitoring, imaging surveillance, seizure prophylaxis, and long-term antimicrobial therapy. Complications such as recurrence, ventriculitis, or residual neurological deficits require vigilant follow-up.

Brain abscess management demands precise neurosurgical judgment, early intervention, and sustained multidisciplinary care to achieve favorable neurological outcomes.