craniotomy


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Craniotomy

 

Definition

Surgical removal of part of the skull to expose the brain.

Purpose

A craniotomy is the most commonly performed surgery for brain tumor removal. It may also be done to remove a blood clot and control hemorrhage, inspect the brain, perform a biopsy, or relieve pressure inside the skull.

Precautions

Before the operation, the patient will have undergone diagnostic procedures such as computed tomography scans (CT) or magnetic resonance imaging (MRI) scans to determine the underlying problem that required the craniotomy and to get a better look at the brain's structure. Cerebral angiography may be used to study the blood supply to the tumor, aneurysm, or other brain lesion.

Description

There are two basic ways to open the skull:
  • a curving incision from behind the hairline, in front of the ear, arching above the eye
  • at the nape of the neck around the occipital lobe.
The surgeon marks with a felt tip pen a large square flap on the scalp that covers the surgical area. Following this mark, the surgeon makes an incision into the skin as far as the thin membrane covering the skull bone. Because the scalp is well supplied with blood, the surgeon will have to seal many small arteries. The surgeon then folds back a skin flap to expose the bone.
Using a high speed hand drill or an automatic craniotome, the surgeon makes a circle of holes in the skull, and pushes a soft metal guide under the bone from one hole to the next. A fine wire saw is then moved along the guide channel under the bone between adjacent holes. The surgeon saws through the bone until the bone flap can be removed to expose the brain.
After the surgery for the underlying cause is completed, the piece of skull is replaced and secured with pieces of fine, soft wire. Finally, the surgeon sutures the membrane, muscle, and skin of the scalp.

Preparation

Before the surgery, patients are usually given drugs to ease anxiety, and other medications to reduce the risk of swelling, seizures, and infection after the operation. Fluids may be restricted, and a diuretic may be given before and during surgery if the patient has a tendency to retain water. A catheter is inserted before the patient goes to the operating room.
The scalp is shaved in the operating room right before surgery; this is done so that any small nicks in the skin will not have a chance to become infected before the operation.

Aftercare

Oxygen, painkillers, and drugs to control swelling and seizures are given after the operation. Codeine may be given to relieve the headache that may occur as a result of stretching or irritation of the nerves of the scalp that happens during the craniotomy. Some type of drainage from the head may be in place, depending on the reason for the surgery.
Patients are usually out of bed within a day and out of the hospital within a week. Headache and pain from the scalp wound can be controlled with medications.
A craniotomy is the most commonly performed surgery for brain tumor removal. There are two basic ways to open the skull: a curving incision from behind the hairline in front of the ear and at the nape of the neck (figure A). To reach the brain, the surgeon uses a hand drill to make holes in the skull, pushing a soft metal guide under the bone. The bone is sawed through until the bone flap can be removed to expose the brain (figure B).
A craniotomy is the most commonly performed surgery for brain tumor removal. There are two basic ways to open the skull: a curving incision from behind the hairline in front of the ear and at the nape of the neck (figure A). To reach the brain, the surgeon uses a hand drill to make holes in the skull, pushing a soft metal guide under the bone. The bone is sawed through until the bone flap can be removed to expose the brain (figure B).
(Illustration by Electronic Illustrators Group.)
The bandage on the skull should be changed regularly. Sutures closing the scalp will be removed, but soft wires used to reattach the skull are permanent and require no further attention. The patient should avoid getting the scalp wet until all the sutures have been removed. A clean cap or scarf can be worn until the hair grows back.

Risks

Accessing the area of the brain that needs repair may damage other brain tissue. Therefore, the procedure carries with it some risk of brain damage that could leave the patient with some loss of brain function. The surgeon performing the operation can give the patient an assessment of the risk of his or her particular procedure.

Normal results

While every patient's experience is different depending on the reason for the surgery, age, and overall health, if the surgery has been successful, recovery is usually rapid because of the good supply of blood to the area.

Abnormal results

Possible complications after craniotomy include:
  • swelling of the brain
  • excessive intracranial pressure
  • infection
  • seizures

Key terms

Craniotome — A type of surgical drill used to operate on the skull. It has a self-controlled system that stops the drill when the bone is penetrated.

Resources

Books

Younson, Robert M., et al., editors. The Surgery Book: An Illustrated Guide to 73 of the Most Common Operations. New York: St. Martin's Press, 1993.

craniotomy

 [kra″ne-ot´ah-me]
1. any operation on the cranium.
2. puncture of the skull and removal of its contents to decrease the size of the head of a dead fetus and facilitate delivery.

cra·ni·ot·o·my

(krā'nē-ot'ō-mē),
1. Opening into the skull.
2. Formerly used operation for perforation of the head of the fetus, removal of the contents, and compression of the empty skull, when delivery by natural means is impossible.
[cranio- + G. tomē, incision]

craniotomy

(krā′nē-ŏt′ə-mē)
n. pl. cranioto·mies
1. Surgical incision into the skull.
2. The cutting or breaking of the fetal skull to reduce its size for removal when normal delivery is not possible.

craniotomy

Neurosurgery An operation in which an opening is made in the skull, a portion of bone is removed to gain access to the brain, and the bone repositioned

cra·ni·ot·o·my

(krā'nē-ot'ŏ-mē)
Opening into the skull, either by attached or detached craniotomy or by trephination.
[cranio- + G. tomē, incision]

craniotomy

(krā-nē-ŏt′ō-mē)
Enlarge picture
CRANIOTOMY
1. Incision through the cranium to gain access to the brain during neurosurgical procedures. See: illustration

Patient care

Preoperative: Procedures are explained and carried out, including antiseptic shampooing of the hair and scalp, hair removal, insertion of peripheral arterial and venous lines and indwelling urinary catheter, and application of pneumatic compression dressings. The patient is prepared for postoperative recovery in the neurological intensive care unit: the presence of a large bulky head dressing, possibly with drains; use of corticosteroids, antibiotics, and analgesics; use of monitoring equipment; postoperative positioning and exercise regimens; and other specific care measures.

Postoperative: Neurological status is assessed according to protocol (every 15 to 30 min for the first 12 hr, then every hour for the next 12 hr, then every 4 hr or more frequently, depending on the patient's stability). Patterns indicating deterioration are immediately reported. The airway is protected, with gentle suctioning used if necessary. Serum electrolyte values are evaluated daily because decreased sodium, chloride, or potassium can alter neurological status, necessitating a change in treatment. Measures are taken to prevent increased intracranial pressure (ICP), and if level of consciousness is decreased, the airway is protected by positioning the patient on the side. After a supratentorial craniotomy, the patient's head is elevated 15° to 30° to increase venous return and to aid ventilatory effort. After infratentorial craniotomy, the patient is kept flat but log-rolled every 2 hours to reduce complications caused by prolonged bedrest.

The patient is gently repositioned every 2 hr and is encouraged to breathe deeply and cough without straining. Fluid is restricted as prescribed (usually 1500 ml/24 hr) or according to protocol, to minimize cerebral edema and prevent increased ICP and seizures. An NPO (“nothing by mouth”) protocol is maintained for 24 to 48 hr to prevent aspiration and vomiting, which can increase ICP. Wound care is provided as appropriate; dressings are assessed for increased tightness (indicative of swelling); and closed drainage systems are checked for patency and for volume and characteristics of any drainage. Excessive bloody drainage, possibly indicating cerebral hemorrhage, and any clear or yellow drainage, indicating a cerebrospinal fluid leak, is reported to the surgeon. Patients who have had a transphenoidal procedure are restricted from nose-blowing and nasal drainage is checked for the presence of cerebrospinal fluid. The patient is observed for signs of wound infection.

Prescribed stool softeners are also administered to prevent increased ICP from straining during defecation. Before discharge, the patient and family are taught to perform wound care; to assess the incision regularly for redness, warmth, or tenderness; and to report such findings to the neurosurgeon. If self-conscious about appearance, the patient can wear a wig, hat, or scarf until the hair grows back and can apply a lanolin-based lotion to the scalp (but not to the incision line) to keep it supple and to decrease itching as the hair grows. Prescribed medications, such as anticonvulsants, may be continued after discharge.

2. After the death of a fetus, the breaking up of the fetal skull to facilitate delivery in difficult parturition.

craniotomy

Surgical opening of the skull, usually for the purpose of operation on the brain or to relieve dangerous pressure within the skull cavity.

cra·ni·ot·o·my

(krā'nē-ot'ŏ-mē)
Opening into the skull, either by attached or detached craniotomy or by trephination.
[cranio- + G. tomē, incision]
References in periodicals archive ?
Through comparing the effects of endoscopic neurosurgery, stereotactic treatment and craniotomy for 30 patients with cerebral hemorrhage in basal ganglia, Cho et al.
Surface landmarks for the junction between the transverse and sigmoid sinuses: application of the "strategic" burr hole for suboccipital craniotomy. Neurosurgery 2009;65(Suppl 6):S37-41.
I just hope I make it through my op so I can see my kids grow old LORNA PRITCHARD on fears over craniotomy
In accordance with these studies mean time from ictus to craniotomy in our series was 12 hours.
There is no consensus on which is better for surgical intervention-burr hole or craniotomy. Previous publications suggested that craniotomy is superior to burr holes for SDE.[3],[5] Burr-hole drainage has a high recurrence rate and may cause damage to friable hyperemic cortex from the catheter, wash solution, or antibiotics.
The reason for measuring between these anatomic structures was to determine the appropriate craniotomy site without violating important anatomic structures such as the sigmoid sinus.
Richard said: "The craniotomy was scary because they had to remove part of my head and replace it.
A further advantage is to create a 3D printed model of the skull preoperatively, plan the surgery and craniotomy defect (often in tumour surgery) and create a template to draw out the proposed craniotomy during live surgery, as well as create the implant mould of the planned defect.
Based on clinical examination, the decision was to perform a craniotomy and excisional biopsy of the frontal lobe lesion for diagnostic and therapeutic purposes.
In this study,we compared the incidence of SSI at three and 12 months after craniotomy with and without implants, with the objective of analyzing the impact reduction in duration of surveillancewould have on incidence.
Management of anesthesia in awake craniotomy. Minerva Anestesiol 2008; 74: 393-408.
She underwent complete excision of the tumour via a craniotomy and histopathology was confirmatory.