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the mortality and morbidity from cvst in various prospective studies range between 8.8% and 44.4% .
conditions predisposing to dural sinus thrombosis include puerperium , trauma , malignancy , disseminated intravascular coagulation , hypercoagulable states , infections , medications ( e.g. , synthetic steroids and contraceptive hormones ) , connective tissue disorders , and dehydration .
headache is the most common symptom ( 8090% ) , other common presentations are focal or generalized seizures , focal neurological deficits , and alteration in sensorium .
occlusions in the superficial venous system are better tolerated and has a better prognosis than thrombosis in the deep venous system because of the extensive collateral supply .
the treatment is aimed at opening up of the occluded sinuses by systemic anticoagulation and giving antiedema measures in the acute phase .
surgical decompression may be the option in cases with a large infarct volume and midline shift . in cases where there is no significant improvement following systemic anticoagulation , direct thrombolysis and mechanical thrombectomy can be considered . here
, we review the techniques and indications for endovascular treatment of cvst and long - term results in 8 cases of dural venous sinus thrombosis ( dvst ) that underwent mechanical thrombectomy with penumbra device with or without concurrent balloon angioplasty and chemical thrombolysis .
out of the 243 cases of acute cvt treated in a quaternary level teaching hospital over a period of 4 years , 8 underwent mechanical thrombectomy using the penumbra system , with or without concurrent balloon angioplasty and chemical thrombolysis .
the ages ranged from 2040 years , with all the patients being females . in all 8 patients , the common presenting feature was headache [ table 1 ] . in 5/8 patients
, there was involvement of the superficial venous system , and in the rest there was involvement of the superficial and deep system .
seven out of 8 cases had venous infarct on the magnetic resonance imaging ( mri ) before endovascular thrombectomy was performed [ figure 1 ] .
clinical and radiological profile mri brain showing areas of restricted diffusion in deep white matter of bilateral frontal lobes ( arrow ) in both diffusion ( a ) and adc maps ( b ) suggestive of infarcts .
there is extensive subacute thrombosis of the entire superior sagittal sinus ( straight arrow ) , both transverse sinuses ( curved arrow ) , straight sinus ( thin arrow ) , and multiple cortical veins in the mrv images ( c - e ) all patients were initially managed medically , systemic anticoagulation ( intravenous unfractionated heparin ) was started to keep the target ptt > 1.5 times the control .
anticonvulsants were started in patients who presented with seizures and also were given prophylatically to others with large venous infarcts involving the cerebral cortex .
all patients were treated for raised intracranial pressure with acetazolamide ( dose ranging from 250 mg thrice a day to 500 mg thrice day ) , intravenous dexamethasone , and hypertonic ( 3% ) saline .
these patients were taken up for endovascular thrombectomy after clinical and radiological worsening . in 5 out of 8 cases ,
balloon angioplasty was concurrently used along with the penumbra system ( penumbra , alameda , usa ) . in the remaining 3 cases , however ,
transarterial cerebral angiography was not routinely performed to survey the dvst detail , except when required .
penumbra mechanical clot retrieval was done with additional balloon angioplasty and chemical thrombolysis were carried out on as required basis . a 6f envoy guide catheter (
codman & shurtleff , inc , raynham , ma , usa ) was first advanced through the femoral vein and placed at the base of the skull .
the blocked dural sinuses were approached using an anteroposterior , lateral , or a combination of both projections . using a 300 cm 0.014 in microwire , a 032 
penumbra reperfusion microcatheter was advanced retrogradely into the anterior two - thirds of the superior sagittal sinus . to disrupt the thrombus , 5 mg tpa , or 2l urokinase
was administered or a 35 mm balloon angioplasty was performed up to 23 times from the distal to the proximal end of the occlusion to sufficiently extract the thrombus . then using a penumbra reperfusion catheter  separator combination ,
thrombus extraction was performed [ figures 25 ] . in cases where there was no significant angiographic recanalization of the sinus after 2 or 3 passes of the penumbra device along with thrombolysis / angioplasty , the procedure was discontinued .
thrombolysis was done by angioplasty ( a ) with a 3 mm  10 cm balloon ( arrow ) followed by mechanical thrombectomy ( b ) with a penumbra catheter system ( arrow ) .
no significant recanalization of superior sagittal sinus ( arrow ) , transverse , and sigmoid sinuses in the post - thrombolysis venogram ( c ) mrv done 5 days after thrombolysis ( a - c ) shows partial resolution of thrombus in the superior sagittal sinus ( straight arrow ) , transverse sinus ( curved arrow ) , and straight sinus with residual filling defects .
mrv done two and a half years later ( d ) shows near complete recanalization of the superior sagittal sinus ( straight arrow ) , transverse ( curved arrow ) and sigmoid sinuses , and straight sinus non - contrast ct brain axial images shows hyperdense area ( arrow ) in the parasagittal aspect of right high parietal region suggestive of a haemorrhagic infarct ( a ) mri brain done the next day shows heterogeneous lesion ( arrows ) in flair and t2 ( b - d ) with blooming on swi ( e ) in right parasagittal parietal region keeping with a infarct with haemorrhagic transformation .
mrv shows filling defects in the superior sagittal sinus ( straight arrow ) , right transverse ( curved arrow ) and sigmoid sinuses ( f and g ) .
ct brain done 6 days later shows ( h ) increase in haemorrhagic component in the right high fronto - parietal region ( straight arrow ) and new hypodense lesion in left high fronto - parietal region ( curved arrow ) with small foci of haemorrhage thrombolysis was done by balloon angioplasty ( a ) using a 3 mm  4 cm balloon ( arrow ) followed by mechanical thrombectomy ( b ) using a penumbra thrombectomy device ( arrow ) .
post - thrombolysis venogram ( c ) shows minimal recanalization of the anterior superior sagittal sinus ( arrow ) and angiogram ( d ) showed no flow in the anterior superior sagittal sinus but a patent posterior segment of superior sagittal sinus medical management was continued in all patients .
a repeat magnetic resonance venography ( mrv ) was performed if the patient showed no significant clinical improvement after 23 days .
after discharge , the patient was followed up with , mrs score assessment and fundal examination .
there were no hemorrhagic events during or after the procedure in any of the patients , nor any immediate or late endovascular - related complications was detected .
good improvement was noted at 6 months with mrs 02 in 5/8 ( 62% ) cases [ table 2 ] .
patients were followed for a mean of 14.5 months ( range : 3 months to 26 months ) ; there were no new neurological events during the follow - up period .
venous sinus thrombosis is a rare and potentially life - threatening condition , with a 30-day fatality rate of 3.4% in a multicentre international prospective study .
intravenous anticoagulation with heparin , followed by oral anticoagulation is the front - line treatment .
when the clinical condition fails to respond despite standard medical management , endovascular therapy can be undertaken .
all 8 patients described here were young , otherwise healthy individuals with severe and progressive neurological symptoms in spite of standard medical therapy . before the era of mechanical thrombectomy devices ,
found that local thrombolysis was associated with a non - negligible incidence of major bleeding complications , including intracranial bleeding , potentially affecting patient outcome . in this study ,
urokinase was used because it was readily available and less expensive than rtpa . in only one case
the use of mechanical thrombectomy with or without concurrent chemical thrombolysis has been reported using other devices , such as balloon angioplasty , the angiojet rheolytic catheter ( possis medical , minneapolis , minnesota , usa ) , the merci retriever device ( concentric medical , mountain view , california , usa ) , and the solitaire fr retrieval device ( covidien , irvine , ca , usa ) , with each having their own inherent limitations . in 3 out of 8 cases ,
thrombolysis was combined with balloon angioplasty and mechanical thrombectomy to aid in clot retrieval . here ,
we report possibly the largest series using the penumbra system for mechanical thrombectomy in dvst .
the penumbra system is a modification of the manual proximal aspiration technique and consists of a dedicated reperfusion catheter connected to a pump , which applies continuous aspiration . a microwire with an olive - shaped tip called the separator
is used to clear the tip of the reperfusion catheter from clot fragments to avoid obstruction .
the ps has shown safety and efficacy in the mechanical treatment of acute ischemic stroke due to thromboembolism . in this report
, the procedures utilized a 0.41 or 0.32 inch penumbra system reperfusion catheter based on the ease of the wire to traverse the thrombus .
balloon angioplasty augmentation was performed in cases where the penumbra system separator did not macerate the clot independently to allow optimum aspiration using the reperfusion catheter .
while most cases did not demonstrate significant recanalization in the immediate post - thrombolysis imaging , they showed improvement in their clinical course after the procedure as well as significant resolution in the follow - up imaging [ figures 3d and 6 ] . there were no intraprocedural complications and no procedure - related complications postoperatively .
the mean follow - up period in this study was 14.5 months , which is unique compared to other similar studies .
none of the patients had recurrent dural sinus thrombosis during the follow - up period .
a multicentre randomized controlled trial may be required to measure the clinical efficacy on a large sample size .
mrv done 4 months later ( a and b ) showed near complete recanalization of the superior sagittal sinus ( straight arrow ) , right transverse ( curved arrow ) , and sigmoid sinuses
cerebral venous sinus thrombosis is a rare but life - threatening condition that demands timely diagnosis and therapy . in cases of rapidly declining neurological status despite standard therapy of systemic anticoagulation
, mechanical thrombectomy appears to be a safe and effective method when used alone or in combination with catheter - directed chemical thrombolysis .
background : in dural venous sinus thrombosis ( dvst ) , the mortality ranges 530% . deep venous system involvement and septic dural sinus thrombosis 
 have a higher mortality rate . in acute occlusion , collateral flow may not be established , which may result in significant edema and mass effect . 
 endovascular interventions may be considered as a treatment option in appropriate high - risk patients with dvst.materials and methods : eight patients with magnetic resonance imaging ( mri)-confirmed dural sinus thrombosis , who did not respond to the conventional standard medical treatment , were subsequently treated with mechanical thrombectomy using the penumbra system. in all cases , medical treatment including anticoagulants were continued following the procedure for a minimum period of 1 year.results:recanalization of the dural sinus thrombosis was achieved in all 8 cases . 
 there were no immediate or late endovascular - related complications . 
 one death occurred due to an unrelated medical event . at 6 months 
 , there was notable improvement in the modified rankin score ( mrs ) , with 5/8 ( 62% ) patients achieving mrs of 2 or less . 
 the follow - up ranged between 3 months and 26 months ( mean : 14.5 months ) , and there were no new neurological events during the follow - up period.conclusion:cerebral venous sinus thrombosis is a rare but life - threatening condition that demands timely diagnosis and therapy . in cases of rapidly declining neurological status despite standard therapy with systemic anticoagulation and anti - edema measures , 
 mechanical thrombectomy could be a lifesaving and effective option . in this study 
 , good outcomes were observed in the majority of patients at long - term follow up .