The evidence of the last decade suggests however, that these leaks result from either a discogenic pathology, such as microspur, osteophyte or intra-dural disc herniation that pierces the dura like a knife, connective tissue disorder (which can often lead to discogenic pathology), or spinal drainage problems.A cerebrospinal fluid leak can be a rare complication of an anterior cervical discectomy and fusion (ACDF). One study suggested a CSF leak to follow from 0.5% of operations. Another study suggests a CSF leak to follow from 1% of operations. In most of these cases repair is successful. Discogenic causes
The most common cause of an intractable "sCSF" leak is discogenic, either from an intra-dural disc herniation, osteophyte or microspur on the disc or vertebral body. "Recent radiological and microsurgical investigations revealed that a calcified, degenerative bony microspur is often the culprit lesion in cases of intractable CSF leaks. Arising from the level of the intervertebrate disk space, these microspurs pierce the ventral dura and produce a slit-like defect a few millimeters in length. These microspurs and the associated CSF leak have to be localized exactly, and then they are amenable to surgical treatment." 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 aortic aneurysms and joint hypermobility.Up to two thirds of those affected demonstrate some type of generalized connective tissue disorder.
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.