Khalil Zahra, M.D Neuro-interventional radiology 1
Disclosure None 2
Outline Etiology and pathogensis Imaging techniques and Features Literature review Treatment modalities Endovascular techniques Long term data review
Idiopathic intracrnial Hypertension( IIH) or Pseudotumor cerebri Primary No definite known etiology and relatively poorly understood Exclude other organic pathology Some imaging Findings at the sella, orbits and brain Treatment options( Endovascular point of view ) Secondary
CRITERIA The current most widely accepted criteria include: 1)signs and symptoms referable only to elevated intracranial pressure (ICP); 2) CSF opening pressure of >25 cm H2O; 3) normal CSF composition; 4) no evidence for mass lesion or other structural cause using modern imaging techniques. 5
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IMAGING ORBIT/Sella Protocol 3 mm Axial T2 with fat suupression. 3 mm STIR coronal covering the orbit and sella Sagittal T1 Axial FLAIR 3D Phase-contrast MRV with velocity encoding at 15cm/s Or Post contrast coronal 3D MRV Venous Morphology and knowledge of normal variants is critical in evaluating the anatomy on angiography 9
Mimics of narrowing on MRV Non-thrombotic Extrensic ( venous compression) or Intrinsic ( arachnoid villi, fibrous septa or intraluminal partitions) Thrombotic ( Sinus thrombosis) 10
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Pathophysiology IIH is controversial. Intracranial venous hypertension leading to decreased CSF reabsorption has been implicated as a potential final common pathway in IIH. Theories: structural abnormalities within arachnoid granulations to dural venous sinus stenosis, or a combination of both. Focal stenosis has been demonstrated in 30 93% of patients using advanced imaging techniques 17
Proposed Pathogenesis 18
Obesity is increasingly perceived as an inflammatory disorder. Cytokines, in particular adipokines, which are specifically produced by adipose tissue, have become a popular research focus. Concentrations of leptin, a product of the obese gene Ob that is involved in weight homoeostasis and appetite regulation, were significantly higher in the CSF of patients with IIH 19
Treatment Modalities Goal is to reduce the CSF pressure Medical management. Therapeutic lumbar puncture and optic nerve sheath fenestration. They have proved to be effective but carry high rates of symptom recurrence or procedural complications. Focal dural venous sinus stenoses have been identified in many patients with IIH Therefor lately stenting of the transvesre sinus stenosis is emerging as a therapeutic option 20
A total of 143 patients with IIH (87% women, mean age 41.4 years, mean body mass index31.6 kg/m2) treated with venous sinus stenting were included in the analysis. Symptoms at initial presentation headache (90%), papilledema (89%), Visual changes (62%) and pulsatile tinnitus (48%). There was a technical success rate of 99% for the stent placement procedure with a total of nine complications (6%). 21
Methods N=128 underwent determination of the pressure gradient across their sinus stenosis prior to stent placement and the mean pressure gradient was 21.8 mm Hg (range 4 160 mm Hg). Location of the stenotic sinus was not reported in enough studies to be relevant to this analysis 22
Follow up Mean 22.3 months 88% of patients experienced improvement in headache, 97% demonstrated improvement or resolution of papilledema. 87% experienced improvement or resolution of visual symptoms and 93% had resolution of pulsatile tinnitus. 23
Conventional treatment Current treatment strategies for IIH are multimodal. Medical treatment including carbonic anydrase-inhibiting diuretics and therapeutic lumbar punctures are the mainstay of treatment and are often effective in patients without severe papilledema However in 2 studies 6 10 years of follow-up, between 38.4% and 45% ofpatients experienced delayed worsening or recurrence of visual symptoms despite optimal medical management. In overweight patients, aggressive weight loss and in some case sgastric bypass procedures have been reported to be effective in reducing ICP and improving visual symptoms 24
Progressive refractory visual symptoms CSF diversion and/or Optic nerve sheath fenestration (ONSF)are indicated to prevent further visual deterioration. Resolution of visual symptoms: shunting : 45% of patients ONSF: 80% of patients Not Risk Free and shunt failure after 1 year can be as high as 75% for lumboperitoneal shunts and 50% for ventriculoperitoneal shunts ONSF: Can carry a 40% complication rate and recurrence of initial visual symptoms in up to 33% of patients 25
Endovascular stents were placed in 142 of the 143 patients (99%), with one patient requiring open surgical stent placement after failed endovascular attempt. 80 of the 116 stents (69%) were placed in the right transverse or sigmoid sinuses. 26
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Retrospective study of 30 patients( Mean age 33)With IIH who underwent stent placement between Oct 2006 and Dec 2012. More than 50% stenosis and a trans-stenosis gradient Follow up catheter angiography 3 months after the procedure 23/30( 77%) follow up imaging was available. 7/30, angiographic follow up of more than 2 yrs( mean of 45 months) 5 required CSF diversion Less than 25% mild in stent stenosis was observed 19/30 had symptomatic improvement ( 70%) with the remaining had persistent symptoms of recurrence following transient improvement. 28
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Some patients may be refractory to stenting and still require permanent CSF diversion. Patients with persistent papilledema post-stenting and highly elevated opening pressure pre-stenting should be followed closely as they are at greatest risk of requiring a shunt and failing stenting. 31
Thank you 32