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Paper text:
hepatic encephalopathy due to intrahepatic portosystemic venous shunts ( ipsvs ) without portal hypertension is a rare condition .
ipsvs is a vascular anomaly , which is defined as a communication between the portal and systemic venous circulations , measuring more than 1 mm in diameter and being at least partially located inside the liver .
interventional treatment for ipsvs is required if the conservative treatments ( restriction of protein and administration of nonabsorbable antibiotics and lactulose ) for hepatic encephalopathy are not sufficiently effective .
because of the invasiveness of surgical interventions , such as shunt ligation , hepatic resection , or liver transplantation , transcatheter embolization of the causative vessel has been widely used for the last 3 decades [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 ] . to our knowledge ,
only 2 case reports [ 3 , 5 ] in which multiple ipsvs in both hepatic lobes with hepatic encephalopathy were treated by transcatheter embolization have been published in english - language literature .
in addition , in both of these cases , transileocolic obliteration was performed through a small abdominal incision , with the patient under general anesthesia . here , we report a case diagnosed with hepatic encephalopathy due to congenital multiple ipsvs in both hepatic lobes , which were successfully treated by percutaneous transhepatic obliteration .
a 67-year - old woman presented with orientation disturbance , bradykinesia , and vomiting for 2 weeks at another hospital , where she had undergone rehabilitation for cerebellar infarction .
brain computed tomography ( ct ) in the hospital revealed no findings that could account for the symptoms . because of a gradual progression in her symptoms
other laboratory tests related to liver function revealed alanine aminotransferase 14 iu / l , aspartate aminotransferase 16
iu / l , alkaline phosphatase 347 iu / l , lactate dehydrogenase 273 iu / l , cholinesterase 137 iu / l , total bilirubin 1.4 mg / dl , albumin 2.7 g / dl , international normalized ratio of prothrombin time 1.60 ( after oral administration of warfarin ) , and a platelet count of 126  10/l .
there was no evidence of underlying liver diseases , such as hepatitis b , hepatitis c , and primary biliary cirrhosis .
. enhanced ct images revealed multiple direct communications between portal and hepatic veins ( fig 1 ) .
thus , we diagnosed this patient with hepatic encephalopathy due to congenital multiple ipsvs . in spite of conservative therapies , including low - protein diet , administration of lactulose , branched - chain amino acids , and kanamycin , and control of defecation
, there was no sufficient reduction in the patient 's serum ammonia levels or improvement in her symptoms .
after an intrahepatic portal vein branch was punctured with sonographic guidance under local anesthesia , a 6-fr sheath introducer ( s - one sheath , terumo clinical supply , gifu , japan ) was inserted into a right portal vein branch .
digital subtraction angiography from the main portal trunk showed multiple portosystemic venous shunts ( fig 2a ) .
the portal venous pressure was 10.0 ( normal range , 510 ) mm hg . a 5-fr balloon catheter ( selecon mp ii , terumo clinical supply ) was inserted into each portal vein branch , and a microcatheter ( progreat  , terumo clinical supply ) was coaxially advanced into the shunt point .
twenty - one detachable coils ( idc , boston scientific , watertown , ma , usa ) and 42 pushable coils ( tornado coil , cook , bloomington , in , usa ) were deployed during balloon inflation .
when ten shunt vessels were embolized , portal venous pressure was elevated to 18.1 mm hg .
accordingly , we decided to complete the procedure , although there were a number of residual shunt vessels ( fig 2b ) .
on the next day of the endovascular shunt closure , the serum ammonia level normalized .
although the patient continued the oral administration of lactulose , branched - chain amino acids , and kanamycin , neither hyperammonemia nor consciousness disorders occurred during the 5-year follow - up period after embolization ( fig 3 ) .
in addition , upper gastrointestinal endoscopy showed no evidence of esophagogastric varices , which suggested a progression of portal hypertension .
although ipsvs usually occurs in patients who have liver cirrhosis or liver trauma , it rarely originates congenitally .
this embryonal anomaly is thought to occur because of persistent anastomoses between cranial and caudal hepatic sinusoids , which comprise vitelline veins and the umbilical vein .
most patients live asymptomatically while young . however , the incidence of hepatic encephalopathy increases with age because of a decreasing tolerance to ammonia in the aged brain .
in addition , the shunt ratio is also related to the development of hepatic encephalopathy .
classified ipsvs into four types on the basis of anatomical variations in the shunt vessels of the liver : type 1 , a single large vessel connecting the portal vein or its right branch to the inferior vena cava ; type 2 , a localized peripheral shunt between the peripheral branches of the portal vein and hepatic veins in one hepatic segment ; type 3 , peripheral portal and hepatic veins connecting through an aneurysm ; type 4 , multiple communications between peripheral portal and hepatic veins diffusely distributed in both lobes . due to the presence of multiple portosystemic venous shunts in both lobes
, the case presented here corresponds to type 4 , which is the rarest type .
interventional treatment for ipsvs should be considered when patients are symptomatic and refractory to medications . since being first reported by ohtomo et al .
, transcatheter embolization has been accepted as a noninvasive and effective treatment for symptomatic ipsvs [ 1 , 2 , 3 , 4 , 5 , 6 , 7 , 8 , 9 ] . the technical approaches of transcatheter embolization for ipsvs include transileocolic , percutaneous transhepatic , and retrograde transcaval embolization . although transileocolic obliteration is feasible for the patients who have multiple shunts in both lobes , as in the present case , this procedure is invasive because a small abdominal incision under general anesthesia is required .
we initially planned to perform the retrograde transcaval approach from the right internal jugular vein because of its noninvasive nature .
however , it was difficult to advance the catheter into the shunt vessels , and antegrade portography could not be performed with this approach .
. however , normal serum ammonia levels were maintained , and no episode of consciousness disorder occurred for 5 years after embolization .
elevated portal venous pressure by a sudden blockage of shunt vessels may cause symptoms such as ascites and bleeding of esophagogastric varices . hence ,
patient follow - up with upper gastrointestinal endoscopy and contrast - enhanced ct scan after embolization is necessary for detecting portal hypertension - related complications .
in addition , we consider it important to monitor the portal venous pressure during the procedure to determine the correct end point . in conclusion ,
we present a case of a patient with hepatic encephalopathy due to congenital multiple ipsvs in both hepatic lobes , which were successfully treated by percutaneous transhepatic obliteration .
transcatheter embolization may be considered an effective therapy for patients who have symptomatic and refractory ipsvs .
hepatic encephalopathy due to intrahepatic portosystemic venous shunts ( ipsvs ) in a non - cirrhotic condition is rare . here 
 we report a rare case of a patient with congenital multiple ipsvs successfully treated by percutaneous transhepatic obliteration . 
 the patient was a 67-year - old woman who presented to our hospital with progressive episodes of consciousness disorder and vomiting . 
 laboratory tests revealed hyperammonemia ( 192.0 g / dl ) , and computed tomography revealed multiple ipsvs in both lobes . 
 there was no evidence of underlying liver disease or hepatic trauma . 
 transcatheter embolization for ipsvs was performed because conservative therapy was not sufficiently effective . 
 after endovascular shunt closure , hepatic encephalopathy improved . the serum ammonia level normalized during the 5-year follow - up period . 
 thus , transcatheter embolization may be an effective therapy for patients with symptomatic and refractory ipsvs . 
 careful follow - up is necessary for portal hypertension - related complications after transcatheter embolization for ipsvs .