16/04/18 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks Pedro Vilela Lisbon - Portugal Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • CSF pressure diseases: • Background • Etiology and Physiopathology • Incidence; prevalence; clinical presentation Summary • Imaging findings • Treatment 1 16/04/18 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • CSF physiology and pressure measurements: • CSF volume – Production: 0.35-0.6mL/min (500-600mL/day) – Volume: 160 mL » ~25% à ventricles » ~75% à subarachnoid space (intracranial and spinal) Background • CSF pressure – Similar to the ICP (intracranial pressure) – Fluctuates ( including during the day) » Monro-Kellie doctrine CSF and CBV have reciprocal changes in order to maintain a normal intracranial pressure (ICP) – Varies: 60 - 250 mmH2O (280 mmH2O in children) Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • CSF physiology and pressure measurements: • CSF volume – Production: 0.35-0.6mL/min (500-600mL/day) – Volume: 160 mL » ~25% à ventricles » ~75% à subarachnoid space (intracranial and spinal) Background • CSF pressure – Similar to the ICP (intracranial pressure) Changes on the CSF volume will – Fluctuates ( including during the day) induce CBV variation at the » Monro-Kellie doctrine CSF and CBV have reciprocal changes in order to maintain venous side (since the veins a normal intracranial pressure (ICP) are more elastic / compressible – Varies: 60 - 250 mmH2O (280 mmH2O in children) and have lower pressure 2 16/04/18 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • CSF physiology and pressure measurements: • CSF opening pressure – Hypertension: > 250 mm H2O (children > 280 mm H2O) – Hypotension: < 60 mm H2O (horizontal Background or lateral decubitus; sitting) » Aliquorrhoea (negative or non- measurable pressure) » Sitting the patient there is an increase of the CSF pressure in normal patients à in intracranial hypotension the CSF pressure maintains < 60 mmH2O From: Lancet Neurol 2015; 14: 655–68 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • CSF physiology and pressure measurements: Arterial flow ArterioVenous (arterial+venous) flow Venous flow Background From Capel C et al T. Heldt (ed.), Intracranial Pressure & Neuromonitoring XVI, Acta Neurochirurgica Supplement, Vol. 126, 2018 3 16/04/18 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • CSF physiology and pressure measurements: Arterial flow ArterioVenous (arterial+venous) flow Venous flow Background ArterioVenous (arterial+venous) flow CSF flow From Capel C et al T. Heldt (ed.), Intracranial Pressure & Neuromonitoring XVI, Acta Neurochirurgica Supplement, Vol. 126, 2018 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • CSF physiology and pressure measurements: CSF and Cerebral flow are Arterial flow closely related: CSF flow secondarily (and passively) due to cerebral blood volume changes Venous flow Systole Background à increase inflow due to arterial flow à Not immediately compensated by venous (out)flow (is delayed CSF flow 90-100ms) à Compensated by immediate CSF outflow From Capel C et al T. Heldt (ed.), Intracranial Pressure & Neuromonitoring XVI, Acta Neurochirurgica Supplement, Vol. 126, 2018 4 16/04/18 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • Intracranial CSF pressure changes: • Types: Low-pressure / High-pressure • Clinical presentation: Headaches • Causes: Idiopathic or Symptomatic (secondary) Background – Idiopathic intracranial hypotension à CSF leak – Idiopathic intracranial hypertension à (?) • If untreated à severe complications: – blindness (CSF hypertension) – coma (CSF hypo and hypertension) Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • Intracranial hypertension: • Background • Etiology and Physiopathology • Incidence; prevalence; clinical presentation Summary • Imaging findings • Treatment 5 16/04/18 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • Intracranial CSF pressure changes: IC Hypertension • Causes: • Hydrocephalus • Intracranial mass • Brain “oedema”; Etiology toxic; inflammatory; infectious lesions • Venous outflow obstruction • Idiopathic From: Lancet Neurol 2015; 14: 655–68 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): – Pseudotumor cerebri – Benign intracranial hypertension (... not always benign ...) • Definition: – Chronic elevation of ICP » Headache + Papilledema + no localizing neurologic signs + normal CSF composition Diagnostic criteria » No definable cause (no secondary cause of ICP increase) hydrocephalus, hypertensive encephalopathy / PRESS, mass lesion, traumatic brain injury, infection, ischemic stroke, venous outflow obstruction, venous thrombosis, metabolic/ drugs (hypoxemia, hypercapnia, hypervitaminosis A, acute liver failure,...), fever, seizures • Imaging: R/O secondary causes of intracranial hypertension 6 16/04/18 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): Diagnostic criteria From Friedman D et al Neurology 2013 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): – Diagnostic criteria Headache Papilledema High CSF opening pressure Diagnostic criteria CSF normal From: Lancet Neurol 2015; 14: 655–68 7 16/04/18 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): Revised diagnostic criteria for the pseudotumor cerebri syndrome in adults and children 2013 Diagnostic criteria From Friedman D et al Neurology 2013 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): • Hypotheses » Increase brain water content (and increase brain volume) » Excess CSF production » Reduced CSF absorption » Increased intra abdominal/thoracic pressure (obesity) » Increase venous pressure Etiology • Venous stenosis (seems to be secondary to increased ICP) » Inflammatory / Immunologic • some cases CSF: presence of oligoclonal bands; increase cytokines » Cellular / molecular dysfunction: • Dysregulation of aquaporin 1 and 4 receptors • Dysregulation of mitochondria • Dysregulation of signaling leptins 8 16/04/18 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • Intracranial hypertension: • Background • Etiology and Physiopathology • Incidence; prevalence; clinical presentation Summary • Imaging findings • Treatment Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH): • Prevalence – Community-based: 1 per 100 000 – Gender: adults F > M (5-15 : 1) (men 10% of cases) » No gender predominance in prepubertal children – All ages (pediatric à elderly): Peak 3 rd decade of life (20-42 y/o) Prevalence – Increased prevalence » Female » Obesity (high BMI) – present > 70% of cases • BMI correlates with CSF opening pressure (? increased intra-abdominal/thoracic pressure) » Sleep apnea » Vitamin A toxicity » Withdrawal of steroid therapy 9 16/04/18 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • Idiopathic Intracranial hypertension (IIH):R – Clinical presentation • Severe headache (> 90% of cases) – Bilateral (mimics migraine) » Constant or fluctuating » Aggravates: Valsalva maneuver, coughing, bending over or lying (increases the intacranial pressure) • Visual complains (~50-75%) – Bilateral Papilloedema » blurred vision, photopsia, or transient visual obscuration L » absent in rare cases (specially in male gender) – IIH without Clinical presentation papilloedema à more frequently associated with dural sinus stenosis – Optic nerve atrophy (bilateral) » associated to longstanding papilloedema • Other associated symptoms: » Diplopia (unilateral or bilateral VI cranial nerve palsy) » Pulsatile tinnitus » Nausea, vomiting (~50%) » Less common: neck or back pain, depression, mild cognitive impairment Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks • Intracranial hypertension: • Background • Etiology and Physiopathology • Incidence; prevalence; clinical presentation Summary • Imaging findings • Treatment 10 16/04/18 Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks – Imaging findings (MRI) from Hartmann AJP et al JCN 2016 – Dural sinus (transverse sinus) stenosis – superior to 50% -(~ 93-97%) – Eye » Posterior globe flattening - (~ 45 - 98%) » Distention of the perioptic subarachnoid space – nerve sheath > 5.5 - 6mm (~ 45 - 89%) » Protrusion of the optic papillae (~ 3- 59%) » Enhancement / Bright DWI spot at the optic nerve head (~ 2 – 50%) – Empty (partially empty) sella (~ 80-83%) from Ducrus A et al Lancet N 2015 Imaging findings » protrusion of the subarachnoid space in the cavum sellae – Other » “Meningocele” and enlargement of Meckel cave, foramen ovale, » “Slit” ventricles » Tonsillar herniation Brain-Degenerative: Intracranial hypertension, hypotension and CSF-leaks – Imaging findings (MRI) – Dural sinus (transverse sinus) stenosis – superior to 50% -(~ 93-97%) – Eye » Posterior globe flattening - (~ 45 - 98%) » Distention of the perioptic subarachnoid space – nerve sheath > 5.5 - 6mm (~ 45 - 89%) » Protrusion of the optic papillae (~ 3- 59%) » Enhancement / Bright DWI spot at the optic nerve head (~ 2 –