Diagnosis
Diagnosis of CSF leakage can be done by various imaging techniques, chemical tests of bodily fluid discharged from a head orifice, or clinical examination. The use of CT, MRI, and assays are the most common types of CSF leak instrumental tests. Many CSF leaks do not show up on imaging and chemical assays, thus such diagnostic tools are not definitive to rule out CSF leaks. A clinician may often depend upon patient history and exam to diagnose, for example: discharge of excessive amount of clear fluid from the nose upon bending over, the increase in headache following a Valsalva maneuver or the reduction of headache when the patient takes a prone position are positive indicators. A clinical exam is often used as a means to diagnose CSF leaks. Improved patient response to conservative treatment may further define a positive diagnosis. The lack of clinician awareness of the signs -symptoms and ailments- of a CSF leak is the greatest challenge to proper diagnosis and treatment, in particular: the loss of the orthostatic characteristic of headache and that every chronic CSF leaker will have a unique symptom set that as a whole contributes to the underlying condition, and diagnosis of, a CSF leak. The primary place of first complaint to a physician is a hospital emergency room. Up to 94% of those with SCSFLS are initially misdiagnosed. Incorrect diagnoses include migraines, meningitis, Chiari malformation, and psychiatric disorders. The average time from onset of symptoms until definitive diagnosis is 13 months.
The set of symptoms associated with a sCSF leak is referred to as a spontaneous cerebrospinal fluid leak syndrome (SCSFLS). A sCSF leak is uncommon but not rare, affecting at least one in 20,000 people and many more who go undiagnosed every year. On average, the condition develops at age 42, and women are twice as likely to be affected. Some people with a sCSF leak have a chronic leak of cerebrospinal fluid despite repeated patching attempts, leading to long-term disability due to pain and being unable to be upright, and surgery is often needed. SCSFLS was first described by German neurologist Georg Schaltenbrand in 1938 and by American neurologist Henry Woltman of the Mayo Clinic in the 1950s. Classification
Spontaneous cerebrospinal fluid leaks are classified into two main types: cranial leaks, and spinal leaks. The vast majority of leaks are spinal. Cranial leaks occur in the head, and in some of these cases, CSF can leak from the nose, or from the ear. Spinal leaks occur when one or more holes form in the dura along the spinal cord. Both cranial and spinal spontaneous CSF leaks cause neurological symptoms as well as spontaneous intracranial hypotension, diminished volume, and pressure of the cranium. While this symptom can be referred to as intracranial hypotension, the intracranial pressure may be normal, with the underlying issue instead being low CSF volume.