Spontaneous intracranial hypotension (SIH) is a rare condition that causes increased intracranial pressure due to decrease of cerebrospinal fluid within the cranial cavity. It is most commonly caused by a spinal fluid leak leading to peri-cranial headaches, visual disturbances and other symptoms. Here, we will be discussing the causes and symptoms, diagnosis, prevention and treatment of spontaneous intracranial hypotension.
Causes and Symptoms of Spontaneous Intracranial Hypotension
Causes
SIH is mainly caused by a spontaneous spinal fluid leak, which is primary or secondary. Primary SIH arises from spontaneous spinal fluid leak and secondary SIH occurs due to a known cause such as a trauma, neurosurgery, or spinal surgery. In rare cases, SIH is caused by spontaneous canalization of a meningeal lymphatic vessel that is associated with the periosteum of the vertebrae.
Symptoms
SIH typically exhibits with peri-cranial headaches that are aggravated by going in an upright position, nausea, vomiting, blurred vision, and vertigo. A person may also experience neck stiffness, tinnitus, hearing loss, spinal pain and cranial nerve palsies. These symptoms may vary from person to person due to cause of the SIH.
Diagnosis of Spontaneous Intracranial Hypotension
Magnetic Resonance Imaging (MRI)
MRI is the most commonly used imaging technique for the diagnosis of spontaneous intracranial hypotension. It helps identify the presence of fluid collection in the head or a dural tear. A dural tear is a tear of the dura mater, the tough tissue that surrounds the brain and spinal cord. This tear can lead to a spinal fluid leak that causes SIH.
Lumbar Puncture and Pressure Measurement
A lumbar puncture, or spinal tap, is an invasive procedure and is used to diagnose SIH. It involves inserting a needle into the lower spine lumbar region to collect the cerebrospinal fluid (CSF). The pressure of the CSF is then measured and compared to normal values. A decrease in pressure is indicative of CSF leak which is associated with SIH.
Prevention and Treatment of Spontaneous Intracranial Hypotension
Prevention
Preventive measures for SIH include avoiding activities that can lead to a spinal fluid leak, such as sports that involve contact with other participants. It is also important to wear a helmet while doing strenuous activities.
Treatment
The treatment of SIH mainly involves conservative methods and surgery. In cases where SIH occurs secondary to spinal tumors or trauma, conservative methods include bed rest and administration of analgesics, such as non-steroidal anti-inflammatory drugs (NSAIDs) and steroids. The goal of surgery is to repair the dural tear that caused the CSF leak. The tear is either repaired with sutures or by inserting a patch over the tear.
People Also Ask
What is a CT scan for SIH?
A CT scan is used to look for compression of the brain caused by SIH. It can also detect spinal abnormalities that are associated with the condition such as CSF leaks.
Can SIH be cured?
Yes, SIH can be cured through conservative measures or surgery. Bed rest and painkillers can be used to provide relief from the symptoms while surgical methods can be used to repair the spinal fluid leak.
What is the difference between SIH and IIH?
The difference between SIH and IIH is that SIH is caused by a decrease in cerebrospinal fluid (CSF) pressure due to a spinal fluid leak while IIH is caused by increased CSF pressure due to idiopathic increased intracranial pressure.
What is the prognosis for SIH?
The prognosis for SIH is usually good if diagnosed and treated early. The typical recovery time is usually within weeks or months and most people with SIH have no permanent deficits or complications.
What should I do if I think I have SIH?
If you think that you may have SIH, it is important to seek medical attention immediately. Your doctor will be able to confirm the diagnosis with a series of tests and provide you with the necessary treatment.
Final Words
Spontaneous Intracranial Hypotension (SIH) is a rare condition in which the normal cerebrospinal fluid pressure within the cranial cavity is decreased due to a spontaneous spinal fluid leak. The symptoms include peri-cranial headaches, visual disturbances, nausea, vomiting and vertigo. Diagnosis is usually done by MRI, CT scan and lumbar puncture and treatment is geared towards the underlying cause of the condition. It is important to seek medical attention as soon as possible if you suspect that you may be suffering from SIH.