Orthostatic headaches Alok Tyagi West of Scotland Regional Headache service Institute of Neurological Sciences Southern General Hospital Glasgow

Orthostatic headaches; Definition Headache that comes on shortly after attaining the upright posture and resolves / improves on lying flat. A classic orthostatic headache is a post dural puncture headache Also seen spontaneously

Overview Clinical presentation ; Headache patterns Other neurological symptoms Investigations ; MRI Management ; Conservative Epidural blood patch

CSF facts Sites of CSF Production; Choroid Plexus Extra-Choroidal Sources Ependymal Layer Brain Parenchyma Spinal Subarachnoid Space Sites of CSF absorption; Arachnoid villi Lymphatic drainage Brain capillaries Choroid plexus Mean CSF volume 157+/-59 ml Spinal CSF volume 49 +/ CSF formed at the rate of 0.35 ml/min

CSF flow

The volume – pressure curve Steiner LA, Andrews PJ. Br J of Anaesth (1): 26–38

Monro-Kellie hypothesis

Wolff’s Headache 2007

Headaches due to low CSF pressure Post dural (post lumbar) puncture headache CSF fistula headache Headache due to spontaneous low CSF pressure

Diagnostic criteria A. Diffuse and/or dull headache that worsens within 15 minutes after sitting or standing, fulfilling criterion D and with 1 of the following: 1. Neck stiffness 2. Tinnitus 3. Hypacusia 4. Photophobia 5. Nausea B. At least 1 of the following: 1. Evidence of low CSF pressure on MRI (eg, pachymeningeal enhancement) 2. Evidence of CSF leakage on conventional myelography, CT myelography, or cisternography 3. CSF opening pressure 60 mm H2O C. No history of dural puncture or other cause of CSF fistula D. Headache resolves within 72 hours after epidural blood patching

Epidemiology Prevalance of 1 in 50,000 in the community In A/E 5 in 100,000 Female:Male=1.5:1 Peak incidence at around 40 yrs of age

Headache patterns in low CSF pressure states Orthostatic headaches (present when upright, relieved by recumbency) Orthostatic headaches evolving in months to chronic lingering headaches Exertional headaches without any orthostatic features Acute thunder clap–like onset of orthostatic headaches Second half of the day headaches (often with some orthostatic features)

Other clinical features of low CSF pressure states Common; Pain or stiff feeling of neck—sometimes orthostatic Nausea, sometimes emesis—often orthostatic Horizontal diplopia (unilateral or bilateral sixth cranial nerve palsy) Third and fourth cranial nerve palsies (much less common than sixth cranial nerve palsy) Dizziness Change in hearing (muffled, distant, distorted, echoed) Visual blurring Photophobia

Etiology of low CSF pressure state Unknown cause (most often) Weakness of the dural sac A. Meningeal diverticula B. Abnormalities of connective tissue Dural tear from spondylosis or disc herniation Trivial trauma Altered distribution of cranio-spinal elasticity (increased compliance of the lumbo-sacral CSF space) Schievink WI. JAMA May 17;295(19):

Head MRI abnormalities in low CSF pressure states Diffuse pachymeningeal enhancement Descent (‘‘sagging’’ or ‘‘sinking’’) of the brain Descent of cerebellar tonsils (may mimic Type I Chiari) Obliteration of some of the subarachnoid cisterns (ie, prepontine or perichiasmatic cisterns) Crowding of the posterior fossa Enlargement of the pituitary Flattening or ‘‘tenting’’ of the optic chiasm Subdural fluid collections (typically hygromas, infrequently hematomas) Engorged cerebral venous sinuses Decrease in size of the ventricles (ventricular collapse) Increase in anteroposterior diameter of the brainstem Mokri B. Neurol Clin Feb;22(1):55-74

MRI brain can be normal in up to 20 % of patients with a headache due to a low CSF pressure state. Mokri B. Mayo Clin Proc.1999;74:

Demonstration of a spinal CSF leak CT myelogram Radionuclide cisternography MR imaging MR myelography

Myelography Early and delayed CT scans need to be performed Multiple levels may need to be scanned Majority of the leaks are at the cervico-thoracic junction or in the thoracic spine Multiple spontaneous CSF leak are common Mokri B. Neurol Clin Feb;22(1):55-74 MRI myelography can be used to identify the site of CSF leak. Vanopdenbosch LJ et al. J Neurol Neurosurg Psychiatry Jun 20 (epub) Wang YF et al. Neurology Dec 1;73(22):1892-8

Spine MRI abnormalities in low CSF pressure states Extra-arachnoid fluid collections (often extending across several levels) Extradural extravasation of fluid (extending to paraspinal soft tissues) Meningeal diverticula Identification of level of the leak (not uncommonly) Identification of the actual site of the leak (very uncommonly) Spinal pachymeningeal enhancement Engorgement of spinal epidural venous plexus

STIR T2

Sensitivity of spinal MRI in the diagnosis of low CSF pressure states is 94 % Watanabe et al. Am J Neuroradiol Jan: 30(1):

CSF findings in low CSF pressure states The variability is considerable CSF pressures are less than 6 cm of water but can be unmeasurable. The CSF pressure can be normal CSF cell count can be high (upto 100 cells) CSF protein can be high (upto 1 gm) CSF glucose is never abnormal

Conservative treatment CSF leaks can resolve spontaneously and some patients may not require any treatment Bed rest Treatments with no evidence base; Hydration Abdominal binder Caffeine (oral or iv) Steroids Theophylline

Epidural blood patch (EBP) Treatment of choice for patients who fail conservative treatment The success rate with each epidural blood patch (when site of CSF leak is unknown) is about 30% There is a higher likelihood of long-term (5 year) resolution of SIH symptoms if patients are treated with EBP rather than conservative measures (??)

Possible mechanisms of action of EBP A replacement of CSF volume by blood An early effect due to volume replacement, a result of dural tamponade A reduction of CSF absorption probably by restriction of CSF flow A latent effect probably from sealing of the leak A reversal of the CSF-blood gradient within the epidural space A decrease in the compliance of the lower spinal CSF space probably a result of dural stiffening Schievink WI. Cephalalgia Dec;28(12):

EBP; The procedure ml blood is injected after which the patient should be placed in a Trendelenburg position for minutes The injection should be terminated at the first patient complaint of pain, back pressure, or headache Complications from an epidural blood patch are backache, neckache, dizziness, auditory disturbances, signs of meningeal irritation, epidural infection, and nerve root compression. Rarely an adhesive arachnoiditis may result If the first blood patch fails a large volume patch should be given ( ml) An interval of 5 days is recommended between blood patches

Level of EBP If the level of the CSF leak is not known a lumbar epidural blood patch should be given first. If the level of the CSF leak is not known and a lumbar epidural blood patch has failed a thoraco-lumbar blood patch should be given. If the CSF leak is localised to the thoracic level a directed thoracic blood patch should be given If the CSF leak is localised to the cervical level a directed cervical blood patch should be given

Management of refractory low CSF pressure states Continuous epidural saline infusion Epidural infusion of Dextran Epidural injection of fibrin glue CSF shunting Intrathecal fluid infusion Surgical repairs of the leak

Indications for surgery for low CSF pressure states Symptoms severe enough to warrant surgical treatment Site of the leak has been identified Symptoms refractory to less invasive measures Mokri B. Cephalalgia 2008 Dec; 28(12);

Complications in low CSF pressure states Cerebral venous sinus thrombosis Savoiardo M. J Neurol Sep;253(9): Subdural haematomas requiring intervention de Noronha RJ. J Neurol Neurosurg Psychiatry Jun;74(6): Epidural blood patch related

Prognosis Group 1Group2Group 3Group 4 Headaches Onsetgradualacutegradual Severitymoderateseveremildmoderate Past historyno yes Other symptoms IHS criteriayes Neurological findingsno yes MRI Brain abnormalyes (any)yes (subdurals)yes (any) Progressresolved no resolutionresolved Mea et al 2009

Conclusions 1 Orthostatic headaches are the hallmark presenting feature of low CSF pressure states Consider a low CSF pressure state as the cause of a chronic daily headache or a new daily persistent headache Ask for an MRI head with contrast if headache is orthostatic

A significant proportion of low CSF pressure headaches do probably resolve with conservative management / time Consider epidural blood patch in patients with low CSF pressure headaches if conservative measures fail Milder symptoms of prolonged duration less likely to resolve completely Conclusions 2