spontaneous cerebrospinal fluid leak (SCSFL) is a medical condition in which the cerebrospinal fluid (CSF) surrounding the human brain and spinal cord leaks out of the surrounding protective dural sac for no apparent reason. A spontaneous CSF leak, as opposed to traumatically caused CSF leaks, arises idiopathically Connective tissue theory Various scientists and physicians have suggested that SCSFLS may be the result of an underlying connective tissue disorder affecting the spinal dura It may also run in families and be associated with aoic aneurysms and joint hypermobility. 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 SCSFLS exhibit features of Marfan syndrome, including tall stature, hollowed chest (pectus excavatum), joint hypermobility and arched palate. However, these patients do not exhibit any other Marfan syndrome presentations. 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 hea 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 hypeension 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 repoed 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 Ref Harrison20th edition pg 2345