442
’
Letters to the Editor
condensed overview of the field of VIR, allowing attendees to learn about the scope of the field and to ask questions of practicing physicians and trainees. Although traditional medical education may allow for glimpses of IR, a dedicated symposium helps emphasize that VIR is a dynamic field, involving numerous organ systems and pathologic processes, while still allowing for patient interaction. Although only 11% of attendees (six of 55) identified themselves as being very familiar with VIR before the symposium, this number increased to 35% (18 of 51) after the event. As training for IR transitions in the coming years, earlier identification and recruitment of talent will be critical to ensure the prosperity of the field. Students are eager to learn more about this exciting and evolving field of medicine, and, irrespective of their future specialty choice, enhanced awareness of procedures and scope of practice of interventional radiologists will help elicit better patient care.
REFERENCES 1. Society of Interventional Radiology. Society of Interventional Radiology Hails Affirmation of Specialty’s Role in Patient Care. [press release] September 12, 2012. 2. Di Salvo DN, Clarke PD, Cho CH, Alexander EK. Redesign and implementation of the radiology clerkship: from traditional to longitudinal and integrative. J Am Coll Radiol 2014; 11(4):413–420. 3. Mulligan P, McIntosh E, Mccullough M, Kim HS. Medical student interventional radiology symposium: the emory experience. JVIR 2013; 24(4):S160–S161. 4. Baerlocher MO, Asch M. Protecting the future: attracting interventional radiology trainees- a medical student’s perspective. Can Assoc Radiol J 2006; 57:147–151.
Cassinotto and Lapuyade
’
JVIR
Institutional review board approval was granted for the preparation of this report. A 56-year-old man was admitted to our hospital for management of acute pancreatitis after several months of worsening weight loss, vomiting, and upper abdominal pain. Arterial phase computed tomography (CT) images showed a pancreatic cephalic pseudocyst with hemorrhagic content (Fig 1) surrounded by a network of tortuous arteries associated with early filling of the portal vein. There were no signs of portal hypertension. A pancreatic head AVM was suspected, and the patient was scheduled for surgical resection. The surgical procedure was canceled after a second episode of severe acute pancreatitis associated with acute myocardial infarction. After endovascular management of the cardiac disease, our multidisciplinary team offered the patient an endovascular embolization of the pancreatic AVM. A 5-F long sheath (Destination; Terumo [Tokyo, Japan]) was placed into the abdominal aorta using a right femoral approach. Selective arteriography confirmed the pancreatic head AVM with arterial feeders originating mainly from the hepatic artery and the superior mesenteric artery, an abnormal dense arterial network entwining the pancreatic head, and early filling of the portal vein through enlarged drainage veins (Fig 2). Selective embolization of AVM feeding branches was performed using ethylene vinyl alcohol copolymer (Onyx18; Covidien) injected via a 2.4-F microcatheter (Progreat; Terumo) (Fig 3). The Onyx volumes used for embolization included 3.5 mL in pancreaticoduodenal arcades arising from the inferior pancreaticoduodenal artery, 2 mL in the gastroduodenal artery, and 0.5 mL into the dorsal pancreatic artery arising from the
Pancreatic Arteriovenous Malformation Embolization with Onyx From: Christophe Cassinotto, MD Bruno Lapuyade, MD Department of Diagnostic and Interventional Imaging (C.C., B.L.) Centre Hospitalier Universitaire de Bordeaux 1 Avenue de Magellan 33604 Pessac, France INSERM U1053 (C.C.) University of Bordeaux Bordeaux, France
Editor: Arteriovenous malformations (AVMs) involving digestive organs are rare. We report the case of a patient with a congenital pancreatic AVM that was diagnosed after recurrent episodes of acute pancreatitis and managed using ethylene vinyl alcohol copolymer (Onyx; Covidien, Dublin, Ireland) embolization. Neither of the authors has identified a conflict of interest. http://dx.doi.org/10.1016/j.jvir.2014.11.036
Figure 1. Pancreatic head AVM responsible for acute pancreatitis with a hemorrhagic pseudocyst of the pancreatic head. Arterial phase CT scan with multi-intensity projection reconstruction in the axial plane shows the hemorrhagic pseudocyst of the pancreatic head (asterisk) surrounded by a racemose intrapancreatic vascular network and large drainage veins (arrows).
Volume 26
’
Number 3
’
March
’
2015
common hepatic artery. The procedure required approximately 3.5 hours, with 56 minutes of fluoroscopy. Final angiograms confirmed the absence of residual AVM nidus arising from the hepatic artery (Fig 4). Superior mesenteric artery angiography showed
Figure 2. Arteriography confirming the diagnosis of pancreatic head AVM. Selective angiography of the inferior pancreaticoduodenal artery shows the contrast medium bolus flowing from an abnormal arterial network (stars) directly into the portal venous system via large drainage veins (arrows). PV ¼ portal vein.
Figure 3. Selective arteriography of the gastroduodenal artery. After Onyx embolization of the pancreaticoduodenal arcades arising from the superior mesenteric artery, gastroduodenal artery angiography shows the arteries feeding the right portion of the AVM (white stars) with the persistence of shunting. PV ¼ portal vein.
443
a persistent small nidus in the plane of the uncus but with no visible feeding arteries. Upper endoscopy performed 1 week later revealed a large hemicircumferential ulcer of the external wall of the second duodenal portion without bleeding. Small black filaments were seen embedded beneath the mucosa, likely representing Onyx. Proton pump inhibitors were prescribed. We percutaneously drained a right retroperitoneal abscess 3 weeks after the procedure, which was attributed to an infected pancreatic fluid collection. The latter was attributed to the severe acute pancreatitis that had occurred before AVM embolization. The patient was discharged 5 weeks after the procedure when his cardiac status was satisfactory and after regaining sufficient weight. At the 8-month follow-up evaluation, the patient had recovered good performance and nutritional status and no longer had symptoms. Catheter angiography and a multiphase CT scan demonstrated complete regression of the pancreatic AVM and no visible draining veins or shunting to the portal vein (Fig 5). The diagnosis of AVM in the digestive organs has been made more frequently with progress in medical imaging. Although pancreatic AVM can be seen in patients with Osler-Weber-Rendu syndrome, most cases are congenital (1). Pancreatic AVM is considered asymptomatic when diagnosed incidentally, but most cases are found after gastrointestinal or pancreatic bleeding secondary to portal hypertension or rupture of abnormal vessels. Pancreatic AVMs may also lead to acute pancreatitis with pseudocysts, as in our patient.
Figure 4. Final celiac angiogram shows no residual AVM nidus arising from the hepatic artery. Onyx has filled much of the nidus and its feeding arteries, including the anterior (white arrowhead) and posterior (black arrowhead) pancreaticoduodenal arcades, the gastroduodenal artery (black arrow), and the dorsal pancreatic artery (white arrow).
444
’
Letters to the Editor
Ravi et al
’
JVIR
type of procedure. This technique could be considered as an efficient therapeutic option for the management of patients with pancreatic AVM when surgical resection is not feasible or to facilitate surgical resection and prevent hemorrhage.
ACKNOWLEDGMENT We thank Professor Vincent Vidal for his tips and tricks.
REFERENCES 1. Chou SC, Shyr YM, Wang SE. Pancreatic arteriovenous malformation. J Gastrointest Surg 2013; 17:1240–1246. 2. Guimaraes M, Wooster M. Onyx (ethylene-vinyl alcohol copolymer) in peripheral applications. Semin Intervent Radiol 2011; 28:350–356. 3. Grasso RF, Cazzato RL, Luppi G, et al. Pancreatic arteriovenous malformation involving the duodenum embolized with ethylene-vinyl alcohol copolymer (Onyx). Cardiovasc Intervent Radiol 2012; 35:958–962.
Figure 5. Superior mesenteric artery angiogram obtained at 8month follow-up evaluation. Anteroposterior view shows no recurrence of the AVM; no nidus or shunting is visible.
Embolization of the AVM was technically difficult because there were many arterial feeders of different sizes. Permanent embolic agents should be used for embolization of the arterial bed of the AVM nidus. In this setting, Onyx seemed to be the most effective embolic agent. Although N-butyl cyanoacrylate has been used as an embolic agent, Onyx seemed safer to us in the setting of a complex procedure with many embolization sites given its short solidification time and lower risk of catheter obstruction (2). Another potential advantage of Onyx over N-butyl cyanoacrylate is that it may be injected over a longer period, perhaps allowing more efficient filling of the nidus. Grasso et al (3) first described the use of Onyx for embolization of a pancreatic head AVM diagnosed on the basis of gastrointestinal bleeding in a 48-yearold man. After the procedure, the patient experienced abdominal pain for 15 days, after which endoscopy revealed two duodenal ulcers. Our patient also had a large duodenal ulcer. Although this complication was asymptomatic, there is a high risk of ischemic duodenal ulcerations or necrosis after complete embolization of pancreaticoduodenal arcades. Patients should systematically receive preventive pharmacologic gastric protection. No subsequent episodes of pancreatitis occurred after embolization of the AVM either during the prolonged initial hospital stay or during 8 months of follow-up. In this reported case, Onyx embolization resulted in complete regression of the AVM. However, the risk of duodenal infarction or ulcer appears to be high after this
Ultrasound-Guided Angio-Seal Deployment From: Rajeev Ravi, MBBS, FRCR Tze Y. Chan, MBChB, FRCR Usman H. Shaikh, MBChB, FRCR Richard G. McWilliams, MB, FRCR, EBIR Interventional Radiology Department Royal Liverpool University Hospital Prescot Street Liverpool L7 8XP, United Kingdom
Editor: The use of the Angio-Seal (St. Jude Medical, St. Paul, Minnesota) vascular closure device after retrograde and antegrade femoral artery puncture is well described in the literature (1,2). Minor complications after AngioSeal closure include bleeding, hematoma, and pain. Major complications from the Angio-Seal after common femoral artery (CFA) puncture owing to occlusion and dissection of the femoral artery have been reported (3,4). Technical failure of Angio-Seal closure after antegrade puncture of the CFA can occur as a result of entrapment of the polymer anchor in smaller caliber vessels such as the superficial femoral artery and profunda femoris artery, especially where there is origin stenosis of these vessels. This situation is more likely to occur in low CFA punctures where the tip of the Angio-Seal delivery sheath lies within the superficial femoral artery or profunda femoris artery. Entrapment of the polymer anchor can also occur in the presence of posterior vessel wall plaque. As a result, the anchor may be trapped in a small artery or within plaque leading to intraluminal None of the authors have identified a conflict of interest. http://dx.doi.org/10.1016/j.jvir.2014.10.011
’
Letters to the Editor
condensed overview of the field of VIR, allowing attendees to learn about the scope of the field and to ask questions of practicing physicians and trainees. Although traditional medical education may allow for glimpses of IR, a dedicated symposium helps emphasize that VIR is a dynamic field, involving numerous organ systems and pathologic processes, while still allowing for patient interaction. Although only 11% of attendees (six of 55) identified themselves as being very familiar with VIR before the symposium, this number increased to 35% (18 of 51) after the event. As training for IR transitions in the coming years, earlier identification and recruitment of talent will be critical to ensure the prosperity of the field. Students are eager to learn more about this exciting and evolving field of medicine, and, irrespective of their future specialty choice, enhanced awareness of procedures and scope of practice of interventional radiologists will help elicit better patient care.
REFERENCES 1. Society of Interventional Radiology. Society of Interventional Radiology Hails Affirmation of Specialty’s Role in Patient Care. [press release] September 12, 2012. 2. Di Salvo DN, Clarke PD, Cho CH, Alexander EK. Redesign and implementation of the radiology clerkship: from traditional to longitudinal and integrative. J Am Coll Radiol 2014; 11(4):413–420. 3. Mulligan P, McIntosh E, Mccullough M, Kim HS. Medical student interventional radiology symposium: the emory experience. JVIR 2013; 24(4):S160–S161. 4. Baerlocher MO, Asch M. Protecting the future: attracting interventional radiology trainees- a medical student’s perspective. Can Assoc Radiol J 2006; 57:147–151.
Cassinotto and Lapuyade
’
JVIR
Institutional review board approval was granted for the preparation of this report. A 56-year-old man was admitted to our hospital for management of acute pancreatitis after several months of worsening weight loss, vomiting, and upper abdominal pain. Arterial phase computed tomography (CT) images showed a pancreatic cephalic pseudocyst with hemorrhagic content (Fig 1) surrounded by a network of tortuous arteries associated with early filling of the portal vein. There were no signs of portal hypertension. A pancreatic head AVM was suspected, and the patient was scheduled for surgical resection. The surgical procedure was canceled after a second episode of severe acute pancreatitis associated with acute myocardial infarction. After endovascular management of the cardiac disease, our multidisciplinary team offered the patient an endovascular embolization of the pancreatic AVM. A 5-F long sheath (Destination; Terumo [Tokyo, Japan]) was placed into the abdominal aorta using a right femoral approach. Selective arteriography confirmed the pancreatic head AVM with arterial feeders originating mainly from the hepatic artery and the superior mesenteric artery, an abnormal dense arterial network entwining the pancreatic head, and early filling of the portal vein through enlarged drainage veins (Fig 2). Selective embolization of AVM feeding branches was performed using ethylene vinyl alcohol copolymer (Onyx18; Covidien) injected via a 2.4-F microcatheter (Progreat; Terumo) (Fig 3). The Onyx volumes used for embolization included 3.5 mL in pancreaticoduodenal arcades arising from the inferior pancreaticoduodenal artery, 2 mL in the gastroduodenal artery, and 0.5 mL into the dorsal pancreatic artery arising from the
Pancreatic Arteriovenous Malformation Embolization with Onyx From: Christophe Cassinotto, MD Bruno Lapuyade, MD Department of Diagnostic and Interventional Imaging (C.C., B.L.) Centre Hospitalier Universitaire de Bordeaux 1 Avenue de Magellan 33604 Pessac, France INSERM U1053 (C.C.) University of Bordeaux Bordeaux, France
Editor: Arteriovenous malformations (AVMs) involving digestive organs are rare. We report the case of a patient with a congenital pancreatic AVM that was diagnosed after recurrent episodes of acute pancreatitis and managed using ethylene vinyl alcohol copolymer (Onyx; Covidien, Dublin, Ireland) embolization. Neither of the authors has identified a conflict of interest. http://dx.doi.org/10.1016/j.jvir.2014.11.036
Figure 1. Pancreatic head AVM responsible for acute pancreatitis with a hemorrhagic pseudocyst of the pancreatic head. Arterial phase CT scan with multi-intensity projection reconstruction in the axial plane shows the hemorrhagic pseudocyst of the pancreatic head (asterisk) surrounded by a racemose intrapancreatic vascular network and large drainage veins (arrows).
Volume 26
’
Number 3
’
March
’
2015
common hepatic artery. The procedure required approximately 3.5 hours, with 56 minutes of fluoroscopy. Final angiograms confirmed the absence of residual AVM nidus arising from the hepatic artery (Fig 4). Superior mesenteric artery angiography showed
Figure 2. Arteriography confirming the diagnosis of pancreatic head AVM. Selective angiography of the inferior pancreaticoduodenal artery shows the contrast medium bolus flowing from an abnormal arterial network (stars) directly into the portal venous system via large drainage veins (arrows). PV ¼ portal vein.
Figure 3. Selective arteriography of the gastroduodenal artery. After Onyx embolization of the pancreaticoduodenal arcades arising from the superior mesenteric artery, gastroduodenal artery angiography shows the arteries feeding the right portion of the AVM (white stars) with the persistence of shunting. PV ¼ portal vein.
443
a persistent small nidus in the plane of the uncus but with no visible feeding arteries. Upper endoscopy performed 1 week later revealed a large hemicircumferential ulcer of the external wall of the second duodenal portion without bleeding. Small black filaments were seen embedded beneath the mucosa, likely representing Onyx. Proton pump inhibitors were prescribed. We percutaneously drained a right retroperitoneal abscess 3 weeks after the procedure, which was attributed to an infected pancreatic fluid collection. The latter was attributed to the severe acute pancreatitis that had occurred before AVM embolization. The patient was discharged 5 weeks after the procedure when his cardiac status was satisfactory and after regaining sufficient weight. At the 8-month follow-up evaluation, the patient had recovered good performance and nutritional status and no longer had symptoms. Catheter angiography and a multiphase CT scan demonstrated complete regression of the pancreatic AVM and no visible draining veins or shunting to the portal vein (Fig 5). The diagnosis of AVM in the digestive organs has been made more frequently with progress in medical imaging. Although pancreatic AVM can be seen in patients with Osler-Weber-Rendu syndrome, most cases are congenital (1). Pancreatic AVM is considered asymptomatic when diagnosed incidentally, but most cases are found after gastrointestinal or pancreatic bleeding secondary to portal hypertension or rupture of abnormal vessels. Pancreatic AVMs may also lead to acute pancreatitis with pseudocysts, as in our patient.
Figure 4. Final celiac angiogram shows no residual AVM nidus arising from the hepatic artery. Onyx has filled much of the nidus and its feeding arteries, including the anterior (white arrowhead) and posterior (black arrowhead) pancreaticoduodenal arcades, the gastroduodenal artery (black arrow), and the dorsal pancreatic artery (white arrow).
444
’
Letters to the Editor
Ravi et al
’
JVIR
type of procedure. This technique could be considered as an efficient therapeutic option for the management of patients with pancreatic AVM when surgical resection is not feasible or to facilitate surgical resection and prevent hemorrhage.
ACKNOWLEDGMENT We thank Professor Vincent Vidal for his tips and tricks.
REFERENCES 1. Chou SC, Shyr YM, Wang SE. Pancreatic arteriovenous malformation. J Gastrointest Surg 2013; 17:1240–1246. 2. Guimaraes M, Wooster M. Onyx (ethylene-vinyl alcohol copolymer) in peripheral applications. Semin Intervent Radiol 2011; 28:350–356. 3. Grasso RF, Cazzato RL, Luppi G, et al. Pancreatic arteriovenous malformation involving the duodenum embolized with ethylene-vinyl alcohol copolymer (Onyx). Cardiovasc Intervent Radiol 2012; 35:958–962.
Figure 5. Superior mesenteric artery angiogram obtained at 8month follow-up evaluation. Anteroposterior view shows no recurrence of the AVM; no nidus or shunting is visible.
Embolization of the AVM was technically difficult because there were many arterial feeders of different sizes. Permanent embolic agents should be used for embolization of the arterial bed of the AVM nidus. In this setting, Onyx seemed to be the most effective embolic agent. Although N-butyl cyanoacrylate has been used as an embolic agent, Onyx seemed safer to us in the setting of a complex procedure with many embolization sites given its short solidification time and lower risk of catheter obstruction (2). Another potential advantage of Onyx over N-butyl cyanoacrylate is that it may be injected over a longer period, perhaps allowing more efficient filling of the nidus. Grasso et al (3) first described the use of Onyx for embolization of a pancreatic head AVM diagnosed on the basis of gastrointestinal bleeding in a 48-yearold man. After the procedure, the patient experienced abdominal pain for 15 days, after which endoscopy revealed two duodenal ulcers. Our patient also had a large duodenal ulcer. Although this complication was asymptomatic, there is a high risk of ischemic duodenal ulcerations or necrosis after complete embolization of pancreaticoduodenal arcades. Patients should systematically receive preventive pharmacologic gastric protection. No subsequent episodes of pancreatitis occurred after embolization of the AVM either during the prolonged initial hospital stay or during 8 months of follow-up. In this reported case, Onyx embolization resulted in complete regression of the AVM. However, the risk of duodenal infarction or ulcer appears to be high after this
Ultrasound-Guided Angio-Seal Deployment From: Rajeev Ravi, MBBS, FRCR Tze Y. Chan, MBChB, FRCR Usman H. Shaikh, MBChB, FRCR Richard G. McWilliams, MB, FRCR, EBIR Interventional Radiology Department Royal Liverpool University Hospital Prescot Street Liverpool L7 8XP, United Kingdom
Editor: The use of the Angio-Seal (St. Jude Medical, St. Paul, Minnesota) vascular closure device after retrograde and antegrade femoral artery puncture is well described in the literature (1,2). Minor complications after AngioSeal closure include bleeding, hematoma, and pain. Major complications from the Angio-Seal after common femoral artery (CFA) puncture owing to occlusion and dissection of the femoral artery have been reported (3,4). Technical failure of Angio-Seal closure after antegrade puncture of the CFA can occur as a result of entrapment of the polymer anchor in smaller caliber vessels such as the superficial femoral artery and profunda femoris artery, especially where there is origin stenosis of these vessels. This situation is more likely to occur in low CFA punctures where the tip of the Angio-Seal delivery sheath lies within the superficial femoral artery or profunda femoris artery. Entrapment of the polymer anchor can also occur in the presence of posterior vessel wall plaque. As a result, the anchor may be trapped in a small artery or within plaque leading to intraluminal None of the authors have identified a conflict of interest. http://dx.doi.org/10.1016/j.jvir.2014.10.011
