This may be an initial presentation of a spontaneous CSF leak or appear after treatment such as an epidural patch, and likely indicates a slow CSF leak. While high CSF pressure can make lying down unbearable, low CSF pressure due to a leak can be relieved by lying flat on the back.About 50% of people with a CSFL experience neck pain or stiffness, nausea, and vomiting.Other symptoms of a CSF leak include photophobia, dizziness and vertigo, gait disturbances, tinnitus, facial numbness or weakness, visual disturbances, brain fog or difficulties with concentration, neuralgia, fatigue, fluid dripping from the nose or ears,Aural symptoms are also present in many cases of intracranial hypotension due to CSF leak; including muffled hearing, pulsatile tinnitus, hearing loss. Less common symptoms include double vision (due to cranial nerve 6 palsy) or tremor.Movement disorders are uncommon in spontaneous CSF leaks but occasionally can be one of the major components of the clinical presentation.Some cases of chronic intracranial hypotension due to CSF leak may present as personality changes, altered behaviors and impairment of executive functions, similar to behavioral-variant frontotemporal dementia as the frontal and temporal lobes are affected by downward sagging due to reduced intra-cranial pressures.An untreated CSF leak can result in coma or death as late stage findings as the brainstem herniates through the skull base or foramen magnum . Causes
A spontaneous CSF leak is termed so as it has previously been thought to be idiopathic, meaning the cause is unknown.
Marfan syndrome, Ehlers–Danlos syndrome, and autosomal dominant polycystic kidney disease are the three most common connective tissue disorders associated with SCSFLs. Roughly 20% of patients with a SCSFL exhibit features of Marfan syndrome, including tall stature, hollowed chest (pectus excavatum), joint hypermobility and arched palate. However, no other Marfan syndrome presentations are shown. Spinal drainage theory
Some studies have proposed that issues with the spinal venous drainage system may cause a CSF leak. According to this theory, dural holes and intracranial hypotension are symptoms caused by low venous pressure in the epidural space. When inferior limb muscles pump blood towards the heart and pressure in the inferior vena cava vein becomes negative, the network of epidural veins is overdrained, causing CSF to be aspirated into the epidural space. True leaks can form at weak points in the spinal meninges. Therefore, the observed CSF hypotension is a result of CSF hypovolemia and reduced epidural venous pressure. Other causes
Cranial CSF leaks result from intracranial hypertension in a vast majority of cases. The increased pressure causes a rupture of the cranial dura mater, leading to CSF leak and intracranial hypotension. Patients with a nude nerve root, where the root sleeve is absent, are at increased risk for developing recurrent CSF leaks. Lumbar disc herniation has been reported to cause CSF leaks in at least one case. Degenerative spinal disc diseases cause a disc to pierce the dura mater, leading to a CSF leak.CSF leaks can result from a lumbar puncture procedure.