Basilar skull fracture
If there is a fracture or break in the cranial or skull bones, it is called a skull fracture. When the base of the skull is involved in a head injury, it is a basilar skull fracture or basal skull fracture. It is also known as depressed skull fracture and linear skull fracture. This linear fracture is rare and occurs in only 4% of patients with severe head injury. Falls, injuries caused by penetrating external objects like knives, hammers or axe or gunshot wounds may result in skull fractures. It can also occur when the skull hits a solid object with considerable force. Basilar skull fracture can be called a linear fracture at the base of the skull. Usually, dural tear is associated with this type of fracture. This fracture occurs at specific points on the skull base. While analyzing skull fractures, it is seen that 19-221% of all skull fractures happen to be basilar skull fractures.
There may be a traumatic brain injury when the skull is fractured. The area of the brain injured and the severity of injury is diagnosed by examining the fracture. If bacteria enter inside the skull through this fracture of the skull, it will lead to infection. Sudden blow to the back of the head can also result in a basilar skull fracture.
After a head injury, if there is a leak of a clear fluid from the nose or ears, it indicates that the clear fluid is cerebrospinal fluid (CSF) that surrounds the brain. CSF drains out through the ears or nose, when the skull is fractured and the Meninges or the covering of the brain is torn. The typical nasal drainage due to allergies, cold or crying is different from this drainage of CSF. It is also an indication of a fracture of the frontal bone or the base of the skull i.e. sphenoid or temporal bone or of the ethmoid bones (bones that support the nose and sinuses).
If bleeding from the ears or nose is not due to a cut or a direct blow, it may be an indication of a fracture of the base of the skull. Determine the cause of the bleeding by washing the blood thoroughly and see if the bleeding is from a cut or not. Ascertain the source of bleeding from the ear. It is an indication of a skull fracture if a nose bleed does not stop with home treatment. If bruising or dislocation develops within 24 hours after a head injury, it also indicates a basilar skull fracture. Often bleeding within the skull may occur with a basilar skull fracture. This condition may lead to infection.
Diagnosis is made with laboratory check of the clear dripping fluid for the presence of CSF. A CT scan of the head with the focus on bones can reveal the extent of damage to the bones. CSF otorrhea and bruising over the mastoids commonly known as 'battle sign' is an indication of a fracture of the petrous temporal bone. Rhinorrhea and bruising around the eyes (raccoon eyes) are noticed with anterior cranial fossa fractures. Depending on an associated intracranial pathologic condition, the Glasgow Coma Score and loss of consciousness may differ from patient to patient. Temporary deafness is a possibility but it resolves in about three weeks.
Hemotympanum and mucosal edema in the middle ear fossa cause this temporary hearing loss. Basilar skull fractures sometimes leads to meningitis in some patients. If the bones around the foramen magnum are broken, there is a risk of damage to the blood vessels and nerves exiting the hole.
Chiari malformations or CM are structural defects in the cerebellum. The cerebellum and parts of the brain stem rest in an indented space at the lower rear region of the skull. This is situated above a funnel-like opening (called the foramen magnum) to the spinal cord. When a part of the cerebellum is found located below the foramen magnum, it is called Chiari malformation.
Causes of Chiari malformations
When the bony space is smaller than normal, this causes the cerebellum and brain stem to be pushed downward into the foramen magnum and into the upper spinal canal, thereby blocking the flow of cerebrospinal fluid that surrounds and cushions the brain and spinal cord.
It can also be caused by structural defects in the brain and spinal cord during fetal development due to genetic mutations or lack of proper vitamins or nutrients in the maternal diet. This is called primary CM or congenital CM.
It is also caused later in life if the spinal fluid is drained excessively from the lumbar and thoracic areas of the spine due to injury or infection. This is acquired CM or secondary CM. However, primary is more common than secondary CM.
Types of Chiari malformations
They are classified into different types depending upon the severity of the disorder.
Type 1 involves extension of the cerebellar tonsils in the foramen magnum involving brain stem. This commonly occurs in adolescence or adulthood.
Type II is called classic CM and it involves extension of both cerebellar and brain stem tissue into the foramen magnum.
Type III is the most serious form of CM. Here the cerebellum and brain stem protrude or herniate through the foramen magnum and into the spinal cord.
Type IV involves an incomplete or underdeveloped cerebellum, a condition known as cerebellar hypoplasia. This is a rare form of CM.
There is yet another form of this disorder which some researchers call as Type 0, in which there is no protrusion of the cerebellum through the foramen magnum but headache and other symptoms are present.
Neck pain, balance problems, muscle weakness, numbness and other abnormal feelings in arms and legs, dizziness, vision problems, difficulty in swallowing, buzzing in the ears, hearing loss, vomiting, insomnia, depression or headache made worse by coughing or straining are some common symptoms.
Symptoms may change from one person to another depending upon the degree of CSF buildup. Patients with type I CM may not have symptoms at all. Adolescents and adults who have CM but no symptoms initially may later in life develop symptoms such as difficulty in swallowing, irritability when being fed, vomiting, arm weakness, a stiff neck, breathing problems, developmental delays and inability to gain weight.
CM is also sometimes associated with certain hereditary syndromes that affect neurological and skeletal abnormalities and disorders that affect bone formation and growth.
It is estimated that the condition occurs in about one in every 1000 births. However, increased use of diagnostic imaging has shown that CM may be much more common. CM occurs more often in women than in men and Type II malformations are more prevalent in certain groups including people of Celtic descent.
As many exhibit no symptoms, their malformations are discovered only during the course of diagnosis or treatment for another disorder. The doctor performs a physical exam and checks the person's memory, cognition, balance, touch, reflexes, sensation and motor skills.
X ray of the head and neck is done to produce images of bones and certain tissues. Though these cannot reveal a CM, they can identify abnormalities that are associated with CM. a and MRI are most often suggested..
Some CMs are asymptomatic and do not interfere with a person's daily activities of daily living and in some cases, medications are used to ease certain symptoms including pain.
Surgery is the treatment option to correct functional disturbances or halt the progression of damage to the central nervous system. Surgery can help reduce symptoms. More than one surgery may be needed to treat the condition. There are different types of surgery performed on adults with CM to create more space for the cerebellum and to relieve pressure on the spinal column.
Surgery involves making an incision at the back of the head and removing a small portion of the bottom of the skull to correct the irregular bony structure. This surgical technique involves destroying tissue with high-frequency electrical currents. Spinal Laminectomy involves surgical removal of the arched, bony roof of the spinal canal to increase the size of the spinal canal and relieve pressure on the spinal cord and nerve roots.
Sometimes, the surgeon makes an incision in the dura to examine the brain and spinal cord. Additional tissue may be added to the dura to create more space for the flow of CSF. Infants may require surgery to reposition the spinal cord and close the opening in the back.
Hydrocephalus is treated with a shunt system that drains excess fluid and relieves pressure from the head. An alternative surgical treatment to improve the flow of CSF is by making a small perforation in the floor of the third ventricle and the CSF is diverted to relieve pressure. Surgeons may open the spinal cord and insert a shunt to drain a syringomyelia. A small catheter is inserted into the syrinx for continued drainage.
Post surgery follow-up
Since surgery involves risk, including the possibility of infection, fluid in the brain, cerebrospinal fluid leakage or problems in wound healing, it is recommended to discuss the pros and cons with the doctor when deciding whether surgery is necessary or not. Surgery reduces symptoms in most people but if nerve injury in the spinal cord has already occurred then this procedure will not reverse the damage. Regular follow up post surgery with examinations by the doctor and periodic imaging tests to assess the outcome of surgery and flow of cerebrospinal fluid is essential.
Syphilis Test VDRL
The syphilis test, VDRL is used to diagnose syphilis. The nontreponemal test is usually performed on blood but may be done on a serum sample or cerebro-spinal fluid (CSF). The test checks for an antibody that can be produced while infected with syphilis. Syphilis test VDRL is not very useful for detecting syphilis in very early or advanced stages. The test is also used to monitor patients' response to syphilis treatment. Syphilis VDRL test can result in false positive result even in the absence of infection due to recent immunization, other bacterial and viral infections and certain chronic conditions (e.g. liver disease, malignancy). Hence, a confirmatory test, the FTA-ABS test is done to check for syphilis-specific antibodies. Though no special preparation is required on the part of an individual who is to be tested, health care officials recommend abstaining from alcohol consumption 24 hours before a VDRL test.
Bibliography / Reference
Collection of Pages - Last revised Date: March 23, 2019