endovascular treatment of aortic pathologies has become the predominant form of repair.1 ) standard endovascular repair of aortic pathologies , in which the internal iliac artery is generally embolized , can lead to complications , such as buttock claudication , colon ischemia , and erectile dysfunction.2 ) therefore , antegrade flow of the internal iliac artery should be conserved , particularly in young patients . to address this problem , various scalloped , fenestrated , and branched aortic stent grafts have been developed and studied . most of these stent grafts are dedicated iliac branch grafts that require at least a 6-week customization period and are very costly.3 ) also , they are currently unavailable for use in china . modified fenestrated stent grafts ( mfsgs ) are a safe and effective alternative for treatment of patients with juxtarenal aneurysms , for whom no other alternatives are available . only a few cases of mfsg use in the treatment of iliac pathologies have been reported.4 ) the current report describes the treatment of isolated iliac dissection with an mfsg with preservation of the internal iliac artery . a 54-year - old man was admitted with complaints of backache that had lasted two weeks . cross - sectional computed tomography ( ct ) and three - dimensional reconstructed images showed a slightly dilated common iliac artery ( cia ) , as well as dissection from the cia to the external iliac artery with intimal tears in the cia , without dilation of the internal iliac artery ( fig . 1 ) . given the patient 's age , possible inflammatory adhesion around the dissection , absence of dilation of the internal artery , and the desire to minimize the risks of colon ischemia , buttock claudication , and impotence , we proceeded with an attempt at endovascular dissection repair with an mfsg . the modified graft was created using a 16 mm13 mm80 mm endurant stent graft ( medtronic , minneapolis , mn , usa ) . the first six stents of the graft were deployed , leaving the remaining stents loaded in the sheath . a sterile marking pen was used to mark the location of the fenestrations based on both length and clock face measurements that had been previously determined with image reconstruction software ( ge adw4.5 , connecticut , usa ) . an ophthalmologic cautery was used to carefully burn the dacron fabric to create the fenestration ( fig . the stent strut from the original iliac stent graft limb was secured to the polyester graft with continuous 6 - 0 prolene sutures . a longitudinal radiopaque marker was sutured to the polyester graft for orientation just below the position of the fenestrated ostium using 6 - 0 prolene sutures ( ethicon , west somerville , nj , usa ) ( fig . the modified graft was resheathed into the original sheath using interrupted silk sutures to collapse each stent . an aortogram revealed right iliac dissection with intimal tears in the common iliac artery , which was limited to the proximal end of the external iliac artery at the left anterior oblique ( lao ) 40+caudal ( caud ) 15 projection angle ( fig . proper orientation of the graft was confirmed by rotating the mfsg clockwise under fluoroscopy and adjusting the longitudinal radiopaque marker to the level of the internal iliac artery . we placed a 16 mm13 mm80 mm medtronic endurant endograft below the aortic bifurcate with the distal end positioned at the external iliac artery . the aortogram revealed that the iliac dissection successfully excluded and preserved the flow of the internal iliac artery . thus , a 12 mm40 mm fluency cover stent ( bard , karlsruhe , germany ) was placed distally to extend to the landing zone and ballooned with a coda balloon . repeat angiography showed intact flow into the internal iliac artery covering the dissection and a narrowed endoleak iv , while endoleak ib had disappeared ( fig . three - dimensional reconstructed ct images 5 months later revealed no endoleaks and showed a patent right internal iliac artery . the modified graft was created using a 16 mm13 mm80 mm endurant stent graft ( medtronic , minneapolis , mn , usa ) . the first six stents of the graft were deployed , leaving the remaining stents loaded in the sheath . a sterile marking pen was used to mark the location of the fenestrations based on both length and clock face measurements that had been previously determined with image reconstruction software ( ge adw4.5 , connecticut , usa ) . an ophthalmologic cautery was used to carefully burn the dacron fabric to create the fenestration ( fig . the stent strut from the original iliac stent graft limb was secured to the polyester graft with continuous 6 - 0 prolene sutures . a longitudinal radiopaque marker was sutured to the polyester graft for orientation just below the position of the fenestrated ostium using 6 - 0 prolene sutures ( ethicon , west somerville , nj , usa ) ( fig . the modified graft was resheathed into the original sheath using interrupted silk sutures to collapse each stent . an aortogram revealed right iliac dissection with intimal tears in the common iliac artery , which was limited to the proximal end of the external iliac artery at the left anterior oblique ( lao ) 40+caudal ( caud ) 15 projection angle ( fig . proper orientation of the graft was confirmed by rotating the mfsg clockwise under fluoroscopy and adjusting the longitudinal radiopaque marker to the level of the internal iliac artery . we placed a 16 mm13 mm80 mm medtronic endurant endograft below the aortic bifurcate with the distal end positioned at the external iliac artery . the aortogram revealed that the iliac dissection successfully excluded and preserved the flow of the internal iliac artery . thus , a 12 mm40 mm fluency cover stent ( bard , karlsruhe , germany ) was placed distally to extend to the landing zone and ballooned with a coda balloon . repeat angiography showed intact flow into the internal iliac artery covering the dissection and a narrowed endoleak iv , while endoleak ib had disappeared ( fig . three - dimensional reconstructed ct images 5 months later revealed no endoleaks and showed a patent right internal iliac artery . most cases are related to marfan syndrome , pregnancy , fibromuscular dysplasia , alpha-1-antitrypsin deficiency , athletic training , or atherosclerosis . endovascular treatment is becoming more popular in aortic pathologies.5)6)7)8 ) the risks of internal iliac artery embolization have been well described . preservation of pelvic flow is crucial in various circumstances.2)9 ) the advent of fenestrated endovascular aortic repair , which can reduce aortic pathologies while preserving blood flow to major organs through visceral branches by using fenestrated stent grafts ( fsgs ) , increases the possibility for treatment of these aortic pathologies . however , most fsgs are focused on the use of an iliac branch device or in situ fsg for endovascular treatment of iliac / aortoiliac pathologies.3 ) mfsgs are a safe and effective alternative for treatment of patients with juxtarenal aneurysms , in which no other alternatives are available.10 ) in this study , we demonstrated endovascular treatment of iliac / aortoiliac pathologies with an mfsg . the effectiveness of this procedure is exhibited by preservation of the internal iliac artery , which showed favorable patency . to our knowledge , most mfsgs are used for preservation of renal and left subclavian arteries.11)12 ) few cases of mfsg use in the treatment of iliac / aortoiliac pathologies have been reported.4 ) the current report presents our first clinical use of an mfsg for preservation of the internal iliac artery . measurements of the abdominal aorta and iliac arteries , as well as deployment of longitudinal radiopaque marker , were of paramount importance . patient access vessels must be of adequate diameter to accommodate large sheaths and areas of narrowing or tortuosity within the iliac system may prevent device advancement and positioning . hence , the choice of mfsg must be made on a case - by - case basis . several factors supported our use of an mfsg in this case . first , dedicated iliac branch grafts have been developed and tested but are currently unavailable for use because of a lack of approval from the china food and drug administration ; they also require at least 6 weeks for customization and are more complicated than standard endovascular aortic repair . second , in situ fsg is theoretically another endovascular alternative.13 ) so far , in situ fsg has mainly been used to preserve the left subclavian artery ; there are no published reports of an in situ fsg being used to treat iliac / aortoiliac pathologies . finally , the absences of severe vessel tortuosity , iliac anatomies , and internal artery dilatation are prerequisites for the selection of an mfsg . as a result , for this case , use of an mfsg avoids the need to construct a branched limb and may require minimal or no device modifications compared with other cases . the selection of the proper projection angle is a critical step for the mfsg procedure . lao 40+caud 15 , which are optimal projection angles for displaying the tear of iliac dissection , maintained the internal and external iliac arteries in the same plane for the current case . such techniques include sandwich technology and the bell - bottom technique . in the bell - bottom technique , the landing zone is usually located in a diseased segment of the common iliac artery , which can lead to future growth and development of a type ib endoleak and has a 4% reintervention rate.14 ) the sandwich technique may be difficult in patients with short common iliac arteries along with a narrow - caliber external iliac artery on the same side.15 ) this technique would have been a viable alternative in the current case , but the cost of treatment would have increased . in conclusion , we report our first clinical case of mfsg usage for preservation of the internal iliac artery . mfsg use is feasible and can be applied with devices available in most endovascular centers . it may become the best option due to comparative effectiveness and low cost if it can be shown to be just as safe and effective as commercially available custom devices . what 's more , an mfsg may be used in urgent or emergent cases ( symptomatic or ruptured aneurysms ) , in patients considered hemodynamically stable . the success of fenestrated endovascular iliac / aortoiliac pathologies can facilitate treatment of aortic pathologies involving visceral arteries . the short - term follow - up in this case indicated that the technique was successful , but there are still uncertainties regarding the long - term stability of the stent graft . further studies are required to evaluate its long - term effectiveness and assess any possible reinterventions associated with modified fenestrated stent grafts .