Introduction

Surgically removing a part of the bone of the skull is called craniotomy, this procedure can be done using specialized tools to expose the brain for different reasons.¹ The procedure varies according to the size and complexity, neurosurgeons perform the craniotomy and may need to cooperate with otologic, head-and-neck, reconstructive and oculoplastic surgeons. To treat some medical conditions that happen in the brain, doctors may need direct access to it, this is why craniotomy plays an important role in treating brain tumours, aneurysms, hematomas (blood clots), traumatic head injury, and foreign objects.²

Craniotomy was originally named according to the cranium (area of the skull) to be removed or create a small hole in it. A craniotomy is not just important in the modern century, it has been also documented in history, it is one of the oldest medical interventions in history up to 8,000 years ago. Hippocrates wrote about craniotomy in a book dedicated to head injuries in addition to recommending performing it within the first three days of head trauma.³

Anatomy and Physiology

It is a fact that the human skull is one of the best examples of armour in the human body. Made from several individual plates of bone, it protects the brain, the complex organ responsible for central operations such as thinking, emotion, feelings, and recall. These bony plates are named: the frontal bone (forehead), the parietal bones (top and sides), the occipital bone at the back of the skull, the temporal bones that contain the hearing organs, the sphenoid and ethmoid bones that are located at the base of the skull⁴. In a craniotomy, a neurosurgeon cuts a small portion of the skull with great precision, often avoiding an invasive procedure. This opens up a window through which surgeons can get into particular parts of the brain for procedures such as the surgical removal of tumours, evacuation of blood clots or to treat epilepsy. Craniotomy involves the removal of a small portion of the skull, and depending on the location, different brain functions may be compromised. For instance, frontal craniotomy may alter decision-making capacity or personality; temporal craniotomy, hearing or language. It helps surgeons to know the area to be operated on or removed and enables patients to look for information on the dangers or advantages, which may be associated with the particular area of the brain.¹

Indications for Craniotomy

Craniotomy plays a crucial role in many medical conditions that require controlling the intracranial pressure or removing undesirable contents like tumours as well as foreign bodies. The operation is indicated in the following clinical setting:⁵

• To control and decrease the intracranial pressure
• To manage intraoperative cerebral swelling
• To correct or remove arteriovenous malformation
• To treat epilepsy
• To implant deep brain stimulators
• To remove hematoma
• To drain an abscess
• To remove a tumour

Types of Craniotomy

Different types of craniotomy procedures vary according to many factors like the size and the part of the skull bone,⁶ the most common craniotomies include: 

• Awake craniotomy

In this type of craniotomy, the medical team awakens the patient from the anaesthesia in the operating room to check his response.⁷

• Trans-labyrinthine Craniotomy

The location of Trans-labyrinthine Craniotomy is behind the ear in the scalp, this procedure aims to remove a part of the inner ear bone and the mastoid.

• Orbito-zygomatic Craniotomy

In Orbito-zygomatic Craniotomy, the surgeon targets aneurysms and removes difficult tumours by creating an incision behind the hairline removing the bone that forms the contour of the orbite and the cheeks.

• Eyebrow Craniotomy

In this procedure, the surgeon performs an incision in the eyebrow to access the tumours that are located in the front. 

• Keyhole Craniotomy

This craniotomy involves creating a small hole behind the ear to allow the surgeons access and remove the lesions located deeply in the brain.

• Stereotactic craniotomy

This type requires to be guided by instruments such as computerized tomography (CT) or magnetic resonance imaging (MRI).

• Pterional Craniotomy

Mainly is performed to access and remove tumours, by making an incision at the junction point of 4 bones within the skull (frontal, temporal, sphenoid, and parietal).

Preoperative Considerations

Before undergoing a craniotomy

Which involves removing part of the skull to access the brain thorough preparation is essential. This process includes crucial steps to ensure the safety of the patients and achieve favourable outcomes.

Initial Assessment

The journey begins with an evaluation conducted by a neurologist. This assessment involves reviewing the patient's history conducting examinations and performing tests to identify the underlying condition. Imaging techniques such, as Magnetic Resonance Imaging (MRI)⁸ and Computed Tomography (CT) scans are crucial in this phase. These imaging studies help surgeons pinpoint the location of concern and strategize for the craniotomy procedure.

Preparing for Surgery

Preoperative preparations extend beyond imaging studies. Blood tests and assessments of heart function are conducted to ensure that the patient can safely undergo anaesthesia and surgery. Depending on cases additional tests like brain mapping may be performed to identify brain functions that must be preserved during surgery.⁹

Assessing Risks and Benefits

The conversation phase between the surgeon and the patient is essential. The surgeon explains the risks associated with the surgery, such as bleeding, infection or cognitive impairments. They also discuss expected benefits, like tumour removal and seizure control. This consent form helps patients take a role in making decisions about their healthcare.

Surgical Procedure

During a craniotomy, a complex procedure is performed in which a part of the skull is temporarily removed to get access to the brain. The patient is given anaesthesia. Positioned according to the specific area that needs attention. A precise cut is made in the scalp followed by drilling or cutting to create a separated bone piece. This piece is then slightly lifted to expose the brain. Specialized microscopes and surgical tools are utilized for the operation, which may include tasks such as removing tumours draining clots or treating epilepsy. Throughout the procedure, brain activity is closely monitored using signals to ensure safety. Finally, the bone piece is fixed with plates and screws before closing up the scalp with stitches. After surgery, close observation for infections and providing recovery support are essential.¹⁰

Postoperative Care and Recovery

After a craniotomy, the main focus turns towards ensuring a recovery. In the Intensive Care Unit (ICU) patients are closely monitored for signs, infections and bleeding. Medications such as painkillers and anti-inflammatory drugs are used to manage pain and swelling. Rehabilitation typically starts with physical and occupational therapy sessions tailored to each individual. This personalized approach helps patients regain strength, coordination and cognitive abilities that may have been affected by the surgery. Speech therapy might also be recommended for any communication challenges. Long-term follow-up is essential. Regular visits to the doctor help to track the progress and address any concerns. The time it takes to recover varies depending on the complexity of the surgery and the patient's overall health. With commitment and assistance, most patients can expect an improvement in their functionality.^11,12

Risks and Complications

As we already acknowledged craniotomy is a powerful brain surgery for addressing tumours blood clots and various neurological issues. It is essential to be aware of the risk factors associated with it.

The risks involved in surgery encompass infections and bleeding which can have consequences. Additionally, there is a possibility of complications such as seizures or stroke. The location of the surgery can also influence cognitive and motor functions. For instance, undergoing a lobe craniotomy could impact memory or decision-making abilities. The impact on one's emotional well-being after undergoing brain surgery can be substantial.¹³ Individuals might encounter feelings of worry, sadness or alterations in their behaviour. Although, these potential outcomes should not be overlooked improvements in methods and thorough preparation work towards reducing these effects. Seeking advice from a physician and a neuropsychologist can provide patients with insights into the risks and advantages associated with craniotomy, tailored to their circumstances.

Summary

A craniotomy is a high-powered procedure used by neurosurgeons to treat a variety of brain conditions. Despite its complexity advancements, techniques and careful planning have greatly enhanced safety and outcomes. This article offers an overview of craniotomy covering its background, different types and factors to consider before surgery. By being aware of the risks and benefits patients can actively engage in decision-making with their healthcare team. Through preparation, surgeons, and dedicated rehabilitation efforts craniotomy can lead to improved neurological function and a higher quality of life.