Which are the causes of Spontaneous Intracranial Hypotension?

Spontaneous Intracranial Hypotension (SIH) is a condition characterized by low cerebrospinal fluid (CSF) pressure in the brain, which can lead to various symptoms and complications. While the exact causes of SIH are not fully understood, several factors have been identified as potential contributors to the development of this condition.

CSF Leak: One of the primary causes of SIH is a cerebrospinal fluid leak. CSF is a clear fluid that surrounds and cushions the brain and spinal cord. When there is a tear or hole in the dura mater (the protective membrane surrounding the brain and spinal cord), CSF can leak out, resulting in decreased CSF pressure. This leak can occur spontaneously, without any apparent injury or trauma.

Connective Tissue Disorders: Certain connective tissue disorders, such as Marfan syndrome and Ehlers-Danlos syndrome, have been associated with an increased risk of developing SIH. These conditions affect the strength and integrity of the connective tissues, including the dura mater, making individuals more susceptible to CSF leaks.

Trauma: While most cases of SIH occur spontaneously, head or spinal trauma can also lead to CSF leaks and subsequent intracranial hypotension. Injuries that cause fractures or tears in the dura mater can disrupt the normal CSF pressure and flow, resulting in SIH.

Spinal Procedures: Certain spinal procedures, such as lumbar punctures (spinal taps) or epidural injections, can occasionally cause CSF leaks and subsequent intracranial hypotension. These procedures involve the insertion of a needle into the spinal canal, and if the dura mater is accidentally punctured or damaged, it can lead to CSF leakage.

Idiopathic: In some cases, the exact cause of SIH remains unknown, and it is referred to as idiopathic intracranial hypotension. It is believed that there may be underlying factors or mechanisms that contribute to the development of CSF leaks and subsequent intracranial hypotension, but they have not yet been fully identified.

It is important to note that while these factors are associated with the development of SIH, not everyone with these risk factors will develop the condition. Additionally, there may be other contributing factors that have not yet been discovered or fully understood.