I. What is cranial defect?
Cranial defect is partly due to open cranial trauma or firearm penetrating injury, and partly due to surgical decompression, penetrating damage due to craniosynostosis or removal of craniosynostosis.
Second, how is the cranial defect caused?
1. Open cranial trauma or firearm penetrating injury.
2. Comminuted or depressed skull fractures that cannot be repositioned after reaming surgery.
3. Severe craniocerebral injury or other types of craniocerebral surgery with debridement and decompression as required by the condition.
4. Pediatric growth fracture of the skull.
5. Cranial osteomyelitis and other lesions of the skull itself caused by penetrating cranial destruction or surgery to remove cranial lesions.
What will be the performance of cranial defect?
1. Cranial defects less than 3 cm2 and cranial defects located under the temporal and occipital muscles are mostly without clinical symptoms.
2. Cranial defect syndrome causes headache, dizziness, nausea, loss of muscle strength of limbs, fear of cold, fear of vibration, inattention and other mental symptoms after larger cranial defects.
3. Brain bulge and neurolocalization signs early in cranial defects due to severe cerebral edema, brain tissue dura and cranial defects form myxoid bulge, and embedded in the bone edge, resulting in local ischemic necrosis causing a series of neurolocalization symptoms and signs.
4. The skull defect caused by growth fracture in children is expanding, and osteosclerosis is formed at the periphery of the defect.
4. How to diagnose cranial defect?
1. History of cranial defect caused by trauma, cranial lesion or surgery, etc.
2. What the patient sees on physical examination.
3. Cranial X-ray shows a translucent area at the site of cranial defect.
4. Cranial CT and 3D reconstruction of the skull reveal cerebral edema, brain tissue in the initial stage and brain atrophy, ventricles, ventricular diverticula and encapsulated fluid in the late stage of the skull defect.
Through the above medical history, physical examination and auxiliary examination, the diagnosis is mostly clear and no differentiation is needed.
How to treat skull defect?
Cranial repair is the main treatment strategy.
1. Indications for surgery
(1) Skull defect diameter >3cm.
(2) Skull defect <3cm in diameter, but located in the part that affects the aesthetics.
(3) Those who can induce epilepsy by pressing on the defect and those who have epilepsy associated with meningeal-brain scar formation.
(4) Those who have cranial defect syndrome due to cranial defect, which causes mental burden and affects work and life, and those who require repair.
2. Contraindications for surgery
(1) Intracranial or incisional infection that has been cured for less than six months.
(2) Those whose symptoms of increased intracranial pressure have not been effectively controlled.
(3) Those with severe neurological dysfunction (KPS score <60) or estimated poor prognosis.
(4) Those with extensive scalp scarring resulting in thin scalp and the possibility of poor incision healing or scalp necrosis caused by repair surgery.
3. Timing and basic conditions for surgery
(1) The intracranial pressure has been effectively controlled and stabilized.
(2) The wound is completely healed and free of infection.
(3) In the past, it was mostly advocated that the repair should be done 3-6 months after the first operation, but now it is mostly advocated that the repair should be done 6-8 weeks after the first operation; it is appropriate for the return implantation of the autologous bone flap to be done within 2 months, and the pulling and repositioning method of the subcapsular tendon embedding should not exceed 2 weeks.
(4) Cranial repair is not advocated under 5 years of age because of the rapid growth of the head and tail; 5~10 years of age can be repaired, and it is appropriate to use covered repair, and the repair material should exceed the bone edge by 0.5cm; after 15 years of age, cranial repair is the same as that of adults.
4. Commonly used repair materials are: polymer materials (plexiglass, bone cement, silicone, titanium plate), allogeneic bone materials (less used now), allogeneic materials (such as allogeneic bone decalcification, degreasing and other treatments made of bone matrix gelatin), autologous materials (ribs, scapula, cranial bone, etc.), new materials (high-density porous polyethylene, EH in line with the material artificial bone), at present, the three-dimensional reconstruction of shaped titanium plate is most commonly used.
What is the prognosis of cranial defect?
Common complications after cranial defect repair include subcutaneous fluid, scalp infection, postoperative cerebrospinal fluid leakage, repair material rejection, repair material invagination, repair material fragmentation (Plexiglas), bleeding in the operation area, chronic cutting scalp ulcer (titanium plate) and epilepsy, etc., which should be taken seriously in patient care.