A craniotomy is a surgical procedure where a section of the skull, known as a bone flap, is temporarily removed to expose the brain. This bone flap is carefully taken out using specialized tools and typically replaced after the neurosurgery. The primary purpose of a craniotomy is to allow neurosurgeons direct access to the brain to treat various conditions, whether located deep within the brain or on its surface.
Addressing Brain Tumors and Abnormal Growths
Craniotomies are frequently performed to address brain tumors, both benign and malignant, as well as cysts and abscesses. The procedure allows for the removal of these growths, which alleviates symptoms caused by pressure on the brain or surrounding tissues. Removing as much of the tumor as safely possible is often the goal, helping to slow progression and relieve symptoms. For brain abscesses, which are pus-filled pockets caused by infection, a craniotomy allows for their drainage or complete removal, relieving pressure and preventing spread.
This surgical approach also enables the collection of tissue samples, known as biopsies, for accurate diagnosis. Analyzing these samples helps determine the type and characteristics of the growth, guiding further treatment.
Surgeons use imaging, such as MRI or CT scans, to precisely locate the tumor and guide the procedure. An awake craniotomy may be employed if the tumor is near areas controlling vital functions like speech or movement. This technique allows neurosurgeons to map brain functions in real-time, minimizing damage to critical areas.
Correcting Vascular Malformations and Bleeds
Craniotomies play a significant role in treating conditions involving blood vessels within the brain. This includes addressing cerebral aneurysms, which are balloon-like bulges on artery walls that can rupture and cause bleeding. During a craniotomy, a neurosurgeon can perform microsurgical clipping, placing a tiny metal clip at the base of the aneurysm to block blood flow and prevent rupture or re-bleeding.
Another condition treated via craniotomy is arteriovenous malformations (AVMs), which are abnormal tangles of blood vessels that can lead to hemorrhage or seizures. The procedure allows for the precise removal of these malformations, aiming to eliminate the abnormal blood flow without damaging healthy brain tissue. Surgical removal offers an immediate cure if the entire AVM is resected.
Craniotomies are also performed to evacuate hematomas, which are blood clots that can form within or around the brain, often following a stroke or injury. These include epidural hematomas, subdural hematomas, and intracerebral hematomas. The procedure involves removing the bone flap to access and clear these life-threatening blood collections, thereby relieving pressure on the brain.
Managing Traumatic Injuries and Other Conditions
Craniotomies are crucial for managing severe traumatic brain injuries (TBIs). The procedure can be used to repair depressed skull fractures, where bone fragments are pushed inward, and to remove foreign objects embedded in the brain. This surgical intervention helps to restore the skull’s integrity and prevent further damage or infection.
The procedure also serves to relieve dangerously high intracranial pressure (ICP) resulting from brain swelling after trauma. By creating an opening in the skull, the pressure on the brain can be alleviated, preventing severe neurological damage. In cases of significant brain swelling, the bone flap might be left out temporarily in a procedure called a craniectomy, to allow the brain to expand, and then replaced in a later surgery.
Beyond traumatic injuries, craniotomies are performed for certain cases of epilepsy that do not respond to medication. The surgery aims to remove or modify the specific area of the brain responsible for generating seizures, while preserving essential functions. If the seizure-generating area is located near critical brain regions, an awake craniotomy may be performed to monitor brain function during the procedure. Craniotomy can also be used for specific types of hydrocephalus, a condition involving excess cerebrospinal fluid, by creating new pathways for fluid flow.