Craniotomy

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Craniotomy
Craniotomy Arachnoid.jpg
ICD-9-CM 01.2
MeSH D003399
eMedicine 1890449

A craniotomy is a surgical operation in which a bone flap is temporarily removed from the skull to access the brain. Craniotomies are often critical operations, performed on patients who are suffering from brain lesions, such as tumors, blood clots, removal of foreign bodies such as bullets, or traumatic brain injury (TBI), and can also allow doctors to surgically implant devices, such as deep brain stimulators for the treatment of Parkinson's disease, epilepsy, and cerebellar tremor. The procedure is also used in epilepsy surgery to remove the parts of the brain that are causing epilepsy.

Contents

Craniotomy is distinguished from craniectomy (in which the skull flap is not immediately replaced, allowing the brain to swell, thus reducing intracranial pressure) and from trepanation, the creation of a burr hole through the cranium in to the dura mater.

Procedure

Diagram of the elements of a craniotomy. Diagram showing a craniotomy CRUK 063.svg
Diagram of the elements of a craniotomy.

Human craniotomy is usually performed under general anesthesia but can be also done with the patient awake using a local anaesthetic; the procedure, typically, does not involve significant discomfort for the patient. In general, a craniotomy will be preceded by an MRI scan which provides an image of the brain that the surgeon uses to plan the precise location for bone removal and the appropriate angle of access to the relevant brain areas. The amount of skull that needs to be removed depends on the type of surgery being performed. The bone flap is mostly removed with the help of a cranial drill and a craniotome, then replaced using titanium plates and screws or another form of fixation (wire, suture, etc.) after completion of the surgical procedure. In the event the host bone does not accept its replacement, an artificial piece of skull, often made of PEEK, is substituted. (The PEEK appliance is routinely modeled by a CNC machine capable of accepting a high resolution MRI computer file in order to provide a very close fit, in an effort to minimize fitment issues, and therefore minimizing the duration of the cranial surgery.)[ citation needed ]

Complications

Bacterial meningitis or viral meningitis occurs in about 0.8 to 1.5% of individuals undergoing craniotomy. [1] Postcraniotomy pain is frequent and moderate to severe in nature. This pain has been controlled through the use of scalp infiltrations, nerve scalp blocks, parecoxib, and morphine, morphine being the most effective in providing analgesia.

According to the Journal of Neurosurgery, Infections in patients undergoing craniotomy: risk factors associated with post-craniotomy meningitis, their clinical studies indicated that "the risk for meningitis was independently associated with perioperative steroid use and ventricular drainage".

Within the 334 procedures that they had conducted from males and females, their results concluded that traumatic brain injuries were the predominant causes of bacterial meningitis.

At least 40% of patients became susceptible to at least one infection, creating more interconnected risk factors along the way. From the Infectious Diseases Clinic Erasme Hospital, there had been reports of infections initially beginning from either the time of surgery, skin intrusion, hematogenous seeding, or retrograde infections.

Cerebrospinal fluid shunt (CSF) associates with the risk of meningitis due to the following factors: pre-shunt associated infections, post-operative CSF leakage, lack of experience from the neurosurgeon, premature birth/young age, advanced age, shunt revisions for dysfunction, and neuroendoscopes.

The way shunts are operated on each patient relies heavily on the cleanliness of the site. Once bacteria penetrates the area of a CSF, the procedure becomes more complicated.

The skin is especially necessary to address because it is an external organ. Scratching the incision site can easily create an infection due to there being no barrier between the open air and wound.

Aside from scratching, decubitus ulcer and tissues near the shunt site are also leading pathways for infection susceptibility. [2]

It is also common to give patients seven days of anti-seizure medications post operatively. Traditionally this has been phenytoin, but now is increasingly levetiracetam as it has a lower risk of drug-drug interactions. [3] [4]

See also

Related Research Articles

<span class="mw-page-title-main">Brain abscess</span> Medical condition

Brain abscess is an abscess within the brain tissue caused by inflammation and collection of infected material coming from local or remote infectious sources. The infection may also be introduced through a skull fracture following a head trauma or surgical procedures. Brain abscess is usually associated with congenital heart disease in young children. It may occur at any age but is most frequent in the third decade of life.

<span class="mw-page-title-main">Neurosurgery</span> Medical specialty of disorders which affect any portion of the nervous system

Neurosurgery or neurological surgery, known in common parlance as brain surgery, is the medical specialty concerned with the surgical treatment of disorders which affect any portion of the nervous system including the brain, spinal cord and peripheral nervous system.

<span class="mw-page-title-main">Trepanning</span> Surgically drilling a hole in the skull

Trepanning, also known as trepanation, trephination, trephining or making a burr hole, is a surgical intervention in which a hole is drilled or scraped into the human skull. The intentional perforation of the cranium exposes the dura mater to treat health problems related to intracranial diseases or release pressured blood buildup from an injury. It may also refer to any "burr" hole created through other body surfaces, including nail beds. A trephine is an instrument used for cutting out a round piece of skull bone to relieve pressure beneath a surface.

<span class="mw-page-title-main">Hydrocephalus</span> Abnormal increase in cerebrospinal fluid in the ventricles of the brain

Hydrocephalus is a condition in which an accumulation of cerebrospinal fluid (CSF) occurs within the brain. This typically causes increased pressure inside the skull. Older people may have headaches, double vision, poor balance, urinary incontinence, personality changes, or mental impairment. In babies, it may be seen as a rapid increase in head size. Other symptoms may include vomiting, sleepiness, seizures, and downward pointing of the eyes.

<span class="mw-page-title-main">Lumbar puncture</span> Procedure to collect cerebrospinal fluid

Lumbar puncture (LP), also known as a spinal tap, is a medical procedure in which a needle is inserted into the spinal canal, most commonly to collect cerebrospinal fluid (CSF) for diagnostic testing. The main reason for a lumbar puncture is to help diagnose diseases of the central nervous system, including the brain and spine. Examples of these conditions include meningitis and subarachnoid hemorrhage. It may also be used therapeutically in some conditions. Increased intracranial pressure is a contraindication, due to risk of brain matter being compressed and pushed toward the spine. Sometimes, lumbar puncture cannot be performed safely. It is regarded as a safe procedure, but post-dural-puncture headache is a common side effect if a small atraumatic needle is not used.

<span class="mw-page-title-main">Cerebral edema</span> Excess accumulation of fluid (edema) in the intracellular or extracellular spaces of the brain

Cerebral edema is excess accumulation of fluid (edema) in the intracellular or extracellular spaces of the brain. This typically causes impaired nerve function, increased pressure within the skull, and can eventually lead to direct compression of brain tissue and blood vessels. Symptoms vary based on the location and extent of edema and generally include headaches, nausea, vomiting, seizures, drowsiness, visual disturbances, dizziness, and in severe cases, death.

<span class="mw-page-title-main">Intracranial pressure</span> Pressure exerted by fluids inside the skull and on the brain

Intracranial pressure (ICP) is the pressure exerted by fluids such as cerebrospinal fluid (CSF) inside the skull and on the brain tissue. ICP is measured in millimeters of mercury (mmHg) and at rest, is normally 7–15 mmHg for a supine adult. The body has various mechanisms by which it keeps the ICP stable, with CSF pressures varying by about 1 mmHg in normal adults through shifts in production and absorption of CSF.

<span class="mw-page-title-main">Electrocorticography</span>

Electrocorticography (ECoG), a type of intracranial electroencephalography (iEEG), is a type of electrophysiological monitoring that uses electrodes placed directly on the exposed surface of the brain to record electrical activity from the cerebral cortex. In contrast, conventional electroencephalography (EEG) electrodes monitor this activity from outside the skull. ECoG may be performed either in the operating room during surgery or outside of surgery. Because a craniotomy is required to implant the electrode grid, ECoG is an invasive procedure.

<span class="mw-page-title-main">Cranioplasty</span>

Cranioplasty is a surgical operation on the repairing of cranial defects caused by previous injuries or operations, such as decompressive craniectomy. It is performed by filling the defective area with a range of materials, usually a bone piece from the patient or a synthetic material. Cranioplasty is carried out by incision and reflection of the scalp after applying anaesthetics and antibiotics to the patient. The temporalis muscle is reflected, and all surrounding soft tissues are removed, thus completely exposing the cranial defect. The cranioplasty flap is placed and secured on the cranial defect. The wound is then sealed.

<span class="mw-page-title-main">Decompressive craniectomy</span> Neurosurgical procedure to treat swelling

Decompressive craniectomy is a neurosurgical procedure in which part of the skull is removed to allow a swelling or herniating brain room to expand without being squeezed. It is performed on victims of traumatic brain injury, stroke, Chiari malformation, and other conditions associated with raised intracranial pressure. Use of the surgery is controversial.

<span class="mw-page-title-main">Cerebral shunt</span> Surgical implant to treat hydrocephalus

A cerebral shunt is a device permanently implanted inside the head and body to drain excess fluid away from the brain. They are commonly used to treat hydrocephalus, the swelling of the brain due to excess buildup of cerebrospinal fluid (CSF). If left unchecked, the excess CSF can lead to an increase in intracranial pressure (ICP), which can cause intracranial hematoma, cerebral edema, crushed brain tissue or herniation. The drainage provided by a shunt can alleviate or prevent these problems in patients with hydrocephalus or related diseases.

Cerebrospinal fluid rhinorrhoea refers to the drainage of cerebrospinal fluid through the nose (rhinorrhoea). It is typically caused by a basilar skull fracture, which presents complications such as infection. It may be diagnosed using brain scans, and by testing to see if discharge from the nose is cerebrospinal fluid. Treatment may be conservative, but usually involves neurosurgery.

Post-traumatic epilepsy (PTE) is a form of acquired epilepsy that results from brain damage caused by physical trauma to the brain. A person with PTE experiences repeated post-traumatic seizures more than a week after the initial injury. PTE is estimated to constitute 5% of all cases of epilepsy and over 20% of cases of acquired epilepsy.

<span class="mw-page-title-main">External ventricular drain</span> Medical device

An external ventricular drain (EVD), also known as a ventriculostomy or extraventricular drain, is a device used in neurosurgery to treat hydrocephalus and relieve elevated intracranial pressure when the normal flow of cerebrospinal fluid (CSF) inside the brain is obstructed. An EVD is a flexible plastic catheter placed by a neurosurgeon or neurointensivist and managed by intensive care unit (ICU) physicians and nurses. The purpose of external ventricular drainage is to divert fluid from the ventricles of the brain and allow for monitoring of intracranial pressure. An EVD must be placed in a center with full neurosurgical capabilities, because immediate neurosurgical intervention can be needed if a complication of EVD placement, such as bleeding, is encountered.

Traumatic brain injury can cause a variety of complications, health effects that are not TBI themselves but that result from it. The risk of complications increases with the severity of the trauma; however even mild traumatic brain injury can result in disabilities that interfere with social interactions, employment, and everyday living. TBI can cause a variety of problems including physical, cognitive, emotional, and behavioral complications.

Scalp reconstruction is a surgical procedure for people with scalp defects. Scalp defects may be partial or full thickness and can be congenital or acquired. Because not all layers of the scalp are elastic and the scalp has a convex shape, the use of primary closure is limited. Sometimes the easiest way of closing the wound may not be the ideal or best way. The choice for a reconstruction depends on multiple factors, such as the defect itself, the patient characteristics and surgeon preference.

<span class="mw-page-title-main">Aqueductal stenosis</span> Narrowing of the aqueduct of Sylvius

Aqueductal stenosis is a narrowing of the aqueduct of Sylvius which blocks the flow of cerebrospinal fluid (CSF) in the ventricular system. Blockage of the aqueduct can lead to hydrocephalus, specifically as a common cause of congenital and/or obstructive hydrocephalus.

Awake craniotomy is a neurosurgical technique and type of craniotomy that allows a surgeon to remove a brain tumor while the patient is awake to avoid brain damage. During the surgery, the neurosurgeon performs cortical mapping to identify vital areas, called the "eloquent brain", that should not be disturbed while removing the tumor.

<span class="mw-page-title-main">Cranial drill</span> Tool for drilling simple burr holes (trepanation) or for creating larger openings in the skull

A cranial drill, also known as a craniotome, is a tool for drilling simple burr holes (trepanation) or for creating larger openings in the skull. This exposes the brain and allows operations like craniotomy and craniectomy to be done. The drill itself can be manually or electrically driven, and primarily consists of a handpiece and a drill bit which is a sharp tool that has a form similar to Archimedes' screw, this instrument must be inserted into the drill chuck to perform holes and remove materials. The trepanation tool is generally equipped with a clutch which automatically disengages once it touches a softer tissue, thus preventing tears in the dura mater. For larger openings, the craniotome is an instrument that has replaced manually pulled saw wires in craniotomies from the 1980s.

Alloplasty is a surgical procedure performed to substitute and repair defects within the body with the use of synthetic material. It can also be performed in order to bridge wounds. The process of undergoing alloplasty involves the construction of an alloplastic graft through the use of computed tomography (CT), rapid prototyping and "the use of computer-assisted virtual model surgery." Each alloplastic graft is individually constructed and customised according to the patient's defect to address their personal health issue. Alloplasty can be applied in the form of reconstructive surgery. An example where alloplasty is applied in reconstructive surgery is in aiding cranial defects. The insertion and fixation of alloplastic implants can also be applied in cosmetic enhancement and augmentation. Since the inception of alloplasty, it has been proposed that it could be a viable alternative to other forms of transplants. The biocompatibility and customisation of alloplastic implants and grafts provides a method that may be suitable for both minor and major medical cases that may have more limitations in surgical approach. Although there has been evidence that alloplasty is a viable method for repairing and substituting defects, there are disadvantages including suitability of patient bone quality and quantity for long term implant stability, possibility of rejection of the alloplastic implant, injuring surrounding nerves, cost of procedure and long recovery times. Complications can also occur from inadequate engineering of alloplastic implants and grafts, and poor implant fixation to bone. These include infection, inflammatory reactions, the fracture of alloplastic implants and prostheses, loosening of implants or reduced or complete loss of osseointegration.

References

  1. van de Beek D, Drake JM, Tunkel AR (January 2010). "Nosocomial Bacterial Meningitis". New England Journal of Medicine. 362 (2): 146–154. doi:10.1056/NEJMra0804573. PMID   20071704. S2CID   20506761.
  2. Hansen, Morten S; Brennum, Jannick; Moltke, Finn B.; Dahl, Jørgen B. (December 2011). "Pain treatment after craniotomy: where is the (procedure-specific) evidence? A qualitative systematic review". European Journal of Anaesthesiology. 28 (12): 821–829. doi: 10.1097/EJA.0b013e32834a0255 . PMID   21971206. S2CID   54568552.
  3. Szaflarski, J. P; K. S Sangha; C. J Lindsell; L. A Shutter (2010). "Prospective, randomized, single-blinded comparative trial of intravenous levetiracetam versus phenytoin for seizure prophylaxis". Neurocritical Care. 12 (2): 165–172. doi:10.1007/s12028-009-9304-y. PMID   19898966. S2CID   207368104.
  4. Temkin, N. R; S. S Dikmen; A. J Wilensky; J. Keihm; S. Chabal; H. R Winn (1990). "A randomized, double-blind study of phenytoin for the prevention of post-traumatic seizures". New England Journal of Medicine. 323 (8): 497–502. doi: 10.1056/nejm199008233230801 . PMID   2115976.