Stentgraft Implantation for the Treatment of Postoperative Hepatic Artery Pseudoaneurysm

Purpose

Hepatic artery pseudoaneurysms are a rare but potentially life-threatening complication of major pancreaticobiliary surgery. We evaluated the safety and efficacy of endovascular stentgraft implantation for the management of such vascular lesions.

Materials and Methods

Between May 2013 and October 2015, ten patients with postoperative hepatic artery pseudoaneurysm, of which eight presented with active hemorrhage, were treated with endovascular stentgraft implantation. All patients had undergone major pancreatic or hepatic surgery before (pylorus-preserving pancreaticoduodenectomy, pancreatectomy, hemihepatectomy, extended hemihepatectomy). The pseudoaneurysms were diagnosed 13–202 days after surgery and were associated with postsurgical complications (e.g., leakage of pancreaticojejunal anastomosis).

Results

In 9/10 patients, the pseudoaneurysm was completely excluded via stentgraft implantation. In 1/10 patient, the pseudoaneurysm ruptured during the procedure and was successfully treated by immediate open surgery. In 1/10 patient, a second intervention was performed after 6 days because of rebleeding; this was successfully treated by implantation of a second overlapping stentgraft. Mean follow-up time is 51 days. None of the patients died due to stentgraft- or aneurysm-related complications. Further episodes of hemorrhage were not observed. In one patient, clinically asymptomatic complete occlusion of the stentgraft was discovered at follow-up imaging.

Conclusion

Stentgraft implantation is a safe and effective technique to treat hepatic artery pseudoaneurysms related to major pancreatic or hepatic surgery, especially in the setting of acute hemorrhage.

     

Endovascular intervention for management of pancreatitis-related bleeding: a retrospective analysis of thirty-seven patients at a single institution

PURPOSE

The aim of this study was to assess the outcome of endovascular intervention for pancreatitis-related hemorrhage at a single institution.

METHODS

From January 2000 to October 2012, thirty-seven patients underwent endovascular intervention for the management of pancreatitis-related hemorrhage. The underlying etiology of the disease, clinical symptoms and laboratory findings, abnormalities seen on computed tomography, and details regarding the endovascular procedures were assessed, as were the outcome of each procedure and procedure-related complications.

RESULTS

A total of 41 endovascular procedures were performed in 37 patients. The splenic artery (34.8%) was the most commonly treated artery, and pseudoaneurysm was the most commonly detected abnormality on digital subtraction angiography (78.3%). Transcatheter embolization was performed in the majority of patients (95.1%), while two patients were treated with stent-grafts. Successful hemostasis without rebleeding was achieved in 34 patients (91.9%). Two cases of rebleeding were successfully treated by reintervention. Focal splenic infarction, which developed in eight patients, was either asymptomatic or accompanied by mild, transient fever. Splenic abscess was the only major complication occurring in three patients. Two of these patients died from resulting sepsis, while the third recovered after antibiotic treatment.

CONCLUSION

Endovascular management is effective for achieving hemostasis in patients with pancreatitis-related bleeding and demonstrates low recurrence and mortality rates.Serious bleeding complications have been reported to occur in up to 14.5% of patients with acute and exacerbated chronic pancreatitis and are potentially fatal when left untreated (1). Computed tomography (CT) serves an important role in the diagnosis of pancreatitis-related hemorrhage, demonstrating radiologic features such as the presence of hematomas, hemorrhagic pseudocysts, extravasation of contrast media or the formation of arterial pseudoaneurysms. Timely intervention, either surgical or endovascular, is essential in this clinical setting, especially for active bleeding or pseudoaneurysm formation. Even though the latter may sometimes be clinically silent, arterial pseudoaneurysms are widely considered to be life-threatening “time-bombs” due to their risk of rupture (2–4). The mortality rate of bleeding pseudoaneurysms has been reported to reach as high as 40% when managed conservatively (5).Endovascular treatment has advantages over surgery for managing complications related to pancreatitis. It is less invasive and can be performed in patients with comorbidities who are contraindicated for surgery. Even for those without surgical contraindications, surgery is often difficult owing to severe inflammatory change around the pancreas. Traditionally, the mainstay of endovascular treatment has been transcatheter embolization. More recently, stent-graft placement for exclusion of arterial rupture and pseudoaneurysms has gained popularity. Current literature suggests that such endovascular techniques are effective in achieving hemostasis in patients, and the outcomes are comparable or superior to those of surgery (2, 6, 7). However, despite the widespread popularity of endovascular treatment, the literature is mostly limited to case reports and small case series. We have performed a web-based search of the literature and have found a surprisingly limited number of publications comprising more than a handful of patients in a single study. By performing this retrospective, single-center study, we aim to provide firmer evidence in support of endovascular intervention as the first-line treatment for the management of pancreatitis-related hemorrhage.     

Stent-graft treatment of traumatic carotid artery dissecting pseudoaneurysm

Introduction

Traumatic pseudoaneurysm of the internal carotid artery (ICA) is a rare but serious complication following blunt or penetrating trauma. These lesions are difficult to repair surgically. Endovascular management, including parent vessel occlusion, bare stent placement, and stent-assisted coil placement, are reported to be safe and effective but have certain disadvantages. Placement of covered stent grafts has been recently reported but without enough follow-up results to achieve consensus.

Methods

In this investigation, we present our experience with seven cases of traumatic ICA dissecting pseudoaneurysm treated with stent graft with follow-up between 1 and 33 months.

Results

Among the seven patients, one patient died due to septic shock 7 days after stenting. Follow-up angiography or Doppler ultrasound of the other six patients revealed optimal result with occluded pseudoaneurysm without restenosis of the ICA.

Conclusions

Our results suggest that placement of stent grafts is a safe and effective method for treating ICA traumatic-dissecting pseudoaneurysm.     

Diagnostic accuracy of computed tomography angiography in detection of post traumatic renal vascular injury

Objectives

To evaluate accuracy of computed tomography angiography (CTA) in evaluation of post traumatic renal vascular injury.

Percutaneous Transabdominal Approach for the Treatment of Endoleaks after Endovascular Repair of Infrarenal Abdominal Aortic Aneurysm

Objective

The purpose of this study was to evaluate the technical feasibility and clinical efficacy of percutaneous transabdominal treatment of endoleaks after endovascular aneurysm repair.

Materials and Methods

Between 2000 and 2007, six patients with type I (n = 4) or II (n = 2) endoleaks were treated by the percutaneous transabdominal approach using embolization with N-butyl cyanoacrylate with or without coils. Five patients underwent a single session and one patient had two sessions of embolization. The median time between aneurysm repair and endoleak treatment was 25.5 months (range: 0-84 months). Follow-up CT images were evaluated for changes in the size and shape of the aneurysm sac and presence or resolution of endoleaks. The median follow-up after endoleak treatment was 16.4 months (range: 0-37 months)

Results

Technical success was achieved in all six patients. Clinical success was achieved in four patients with complete resolution of the endoleak confirmed by follow-up CT. Clinical failure was observed in two patients. One eventually underwent surgical conversion, and the other was lost to follow-up. There were no procedure-related complications.

Conclusion

The percutaneous transabdominal approach for the treatment of type I or II endoleaks, after endovascular aneurysm repair, is an alternative method when conventional endovascular methods have failed.     

Endovascular treatment of abdominal aortic paraanastomotic pseudoaneurysms after surgical reconstruction

Purpose

To evaluate the efficacy of endovascular treatment of paraaortic postoperative abdominal aortic pseudoaneurysms.

Materials and methods

From April 1996 to November 2007 five men with paraaortic postoperative abdominal aortic pseudoaneurysm underwent endovascular treatment. Average age was 64.2 years (range 54-73). The average time interval between the primary surgery and endovascular treatment was 12.4 years (4 months-23 years). Three patients were treated by aortouniiliacal stentgrafts and two patients by tube stentgrafts.

Results

Technical success rate was 100%. Pseudoaneurysms were primarily excluded from circulation without perioperative complications in all patients. At follow-up (mean 38.5 months) there were no deaths and no endoleaks. In one patient thrombosis of stentgraft was found and it was successfully treated by thrombectomy. All pseudoaneurysms still continued to be excluded from circulation in the last follow-up.

Conclusion

Endovascular treatment is minimally invasive, effective and safe option of surgery for paraaortic postoperative pseudoaneurysms.     

A Less Invasive Approach for Ruptured Aneurysm with Intracranial Hematoma: Coil Embolization Followed by Clot Evacuation

Objective

The presence of an intracerebral hematoma from a ruptured aneurysm is a negative predictive factor and it is associated with high morbidity and mortality rates even though clot evacuation followed by the neck clipping is performed. Endovascular coil embolization is a useful alternative procedure to reduce the surgical morbidity and mortality rates. We report here on our experiences with the alternative option of endovascular coil placement followed by craniotomy for clot evacuation.

Materials and Methods

Among 312 patients who were admitted with intracerebral subarachnoid hemorrhage during the recent three years, 119 cases were treated via the endovascular approach. Nine cases were suspected to show aneurysmal intracerebral hemorrhage (ICH) on CT scan and they underwent emergency cerebral angiograms. We performed immediate coil embolization at the same session of angiographic examination, and this was followed by clot evacuation.

Results

Seven cases showed to have ruptured middle cerebral artery (MCA) aneurysms and two cases had internal carotid artery aneurysms. The clinical status on admission was Hunt-Hess grade (HHG) IV in seven patients and HHG III in two. Surgical evacuation of the clot was done immediately after the endovascular coil placement. The treatment results were a Glasgow Outcome Scale score of good recovery and moderate disability in six patients (66.7%). No mortality was recorded and no procedural morbidity was incurred by both the endovascular and direct craniotomy procedures.

Conclusion

The results indicate that the coil embolization followed by clot evacuation for the patients with aneurysmal ICH may be a less invasive and quite a valuable alternative treatment for this patient group, and this warrants further investigation.     

Renal Artery Embolization Using a New Liquid Embolic Material Obtained by Partial Hydrolysis of Polyvinyl Acetate (Embol): Initial Experience in Six Patients

Objective

To evaluate the therapeutic efficacy of a new liquid embolic material, Embol, in embolization of the renal artery.

Materials and Methods

Embol is a new embolic material obtained by partial hydrolysis of polyvinyl acetate mixed in absolute ethanol and Iopromide 370 and manufactured by Schering Korea, Kyonggido, Korea. Six patients who underwent embolization of the renal artery using Embol were evaluated. Four were male and two were female and their ages ranged from 11 to 70 (mean, 53) years. Clinical and radiologic diagnoses referred for renal artery embolization were renal cell carcinoma (n = 3), renal angiomyolipoma (n = 2) and pseudoaneurysm of the renal artery (n = 1). After selective renal angiography, Embol was injected through various catheters, either with or without a balloon occlusion catheter. Changes in symptoms and blood chemistry which may have been related to renal artery embolization with Embol were analyzed.

Results

The six patients showed immediate total occlusion of their renal vascular lesions. One of the three in whom renal cell carcinoma was embolized with Embol underwent radical nephrectomy, and the specimen thus obtained revealed 40% tumor necrosis. In the two patients with angiomyolipomas, the tumors decreased in size and abdominal pain subsided. Bleeding from pseudoaneurysm of the renal artery was successfully controlled. Four patients showed symptoms of post-embolization syndrome, and one of these also showed increased levels of blood urea nitrogen and creatinine. One patient experienced transient hypertension.

Conclusion

Embol is easy to use, its radiopacity is adequate and it is a safe and effective embolic material which provides immediate and total occlusion of renal vascular lesions.     

Transcatheter Arterial Embolization of Arterial Esophageal Bleeding with the Use of N-Butyl Cyanoacrylate

Objective

To evaluate the clinical efficacy and safety of a transcatheter arterial embolization (TAE) with N-butyl cyanoacrylate (NBCA) for the treatment of arterial esophageal bleeding.

Materials and Methods

Between August 2000 and April 2008, five patients diagnosed with arterial esophageal bleeding by conventional angiography, CT-angiography or endoscopy, underwent a TAE with NBCA. We mixed NBCA with iodized oil at ratios of 1:1 to 1:4 to supply radiopacity and achieve a proper polymerization time. After embolization, we evaluated the angiographic and clinical success, recurrent bleeding, and procedure-related complications.

Results

The bleeding esophageal artery directly originated from the aorta in four patients and from the left inferior phrenic artery in one patient. Although four patients had an underlying coagulopathy at the time of the TAE, angiographic and clinical success was achieved in all five patients. In addition, no procedure-related complications such as esophageal infarction were observed during this study.

Conclusion

NBCA can be an effective and feasible embolic agent in patients with active arterial esophageal bleeding, even with pre-existing coagulopathy.     

Post-Operative Hemorrhage after Myomectomy: Safety and Efficacy of Transcatheter Uterine Artery Embolization

Objective

To evaluate the safety and clinical efficacy of transcatheter uterine artery embolization (UAE) for post-myomectomy hemorrhage.

Materials and Methods

We identified eight female patients (age ranged from 29 to 51 years and with a median age of 37) in two regional hospitals who suffered from post-myomectomy hemorrhage requiring UAE during the time period from 2004 to 2012. A retrospective review of the patients'' clinical data, uterine artery angiographic findings, embolization details, and clinical outcomes was conducted.

Results

The pelvic angiography findings were as follows: hypervascular staining without bleeding focus (n = 5); active contrast extravasation from the uterine artery (n = 2); and pseudoaneurysm in the uterus (n = 1). Gelatin sponge particle was used in bilateral uterine arteries of all eight patients, acting as an empirical or therapeutic embolization agent for the various angiographic findings. N-butyl-2-cyanoacrylate was administered to the target bleeding uterine arteries in the two patients with active contrast extravasation. Technical and clinical success were achieved in all patients (100%) with bleeding cessation and no further related surgical intervention or embolization procedure was required for hemorrhage control. Uterine artery dissection occurred in one patient as a minor complication. Normal menstrual cycles were restored in all patients.

Conclusion

Uterine artery embolization is a safe, minimally invasive, and effective management option for controlling post-myomectomy hemorrhage without the need for hysterectomy.     

Internal Thoracic Artery Collateral to the External Iliac Artery in Chronic Aortoiliac Occlusive Disease

Objective

To evaluate the incidence and angiographic findings of the collateral pathway involving the internal thoracic artery in patients with chronic aortoiliac occlusive disease.

Materials and Methods

Between March 2000 and Februrary 2001, 124 patients at our hospital underwent angiographic evaluation of chronic aortoiliac occlusive disease, and in 15 of these complete obstruction or severe stenosis of the aortoiliac artery was identified. The aortograms and collateral arteriograms obtained, including internal thoracic arteriograms, as well as the medical records of the patients involved, were evaluated.

Results

In nine patients there was complete occlusion of the infrarenal aorta, or diffuse stenosis of 75% or more in the descending thoracic aorta, and in the other six, a patent aorta but complete occlusion or stenosis of 75% or more of the common iliac artery was demonstrated. Collateral perfusion via hypertrophied internal thoracic arteries and rich anastomoses between the superior and inferior epigastric arteries, reconstituting the external iliac artery, were noted in all fifteen patients, regardless of symptom duration, which ranged from six months to twelve years.

Conclusion

In patients with chronic aortoiliac occlusive disease, the internal thoracic artery, along with visceral collaterals and those from the contralateral side, is one of the major parietal collateral pathways.     

Internal Iliac Artery Embolization during an Endovascular Aneurysm Repair with Detachable Interlock Microcoils

Objective

The purpose of this study was to evaluate the effectiveness of detachable interlock microcoils for an embolization of the internal iliac artery during an endovascular aneurysm repair (EVAR).

Materials and Methods

A retrospective review was conducted on 40 patients with aortic aneurysms, who had undergone an EVAR between January 2010 and March 2012. Among them, 16 patients were referred for embolization of the internal iliac artery for the prevention of type II endoleaks. Among 16 patients, 13 patients underwent embolization using detachable interlock microcoils during an EVAR. Computed tomographic angiographies and clinical examinations were performed during the follow-up period. Technical success, clinical outcome, and complications were reviewed.

Results

Internal iliac artery embolizations using detachable interlock microcoils were technically successful in all 13 patients, with no occurrence of procedure-related complications. Follow-up imaging was accomplished in the 13 cases. In all cases, type II endoleak was not observed with computed tomographic angiography during the median follow-up of 3 months (range, 1-27 months) and the median clinical follow-up of 12 months (range, 1-27 months). Two of 13 (15%) patients had symptoms of buttock pain, and one patient died due to underlying stomach cancer. No significant clinical symptoms such as bowel ischemia were observed.

Conclusion

Internal iliac artery embolization during an EVAR using detachable interlock microcoils to prevent type II endoleaks appears safe and effective, although this should be further proven in a larger population.     

Endovascular Management of Iatrogenic Native Renal Arterial Pseudoaneurysms

Purpose

Our purpose was to evaluate iatrogenic renal pseudoaneurysms, endovascular treatment, and outcomes.

Methods

This retrospective study (2003–2011) reported the technical and clinical outcomes of endovascular therapy for renal pseudoaneurysms in eight patients (mean age, 46 (range 24–68) years). Renal parenchymal loss evaluation was based on digital subtraction angiography and computed tomography.

Results

We identified eight iatrogenic renal pseudoaneurysm patients with symptoms of hematuria, pain, and hematoma after renal biopsy (n?=?3), surgery (n?=?3), percutaneous nephrolithotomy (n?=?1), and endoscopic shock-wave lithotripsy (n?=?1). In six patients, the pseudoaneurysms were small-sized (<20?mm) and peripherally located and were treated solely with coil embolization (n?=?5). In one patient, coil embolization was preceded by embolization with 500–700 micron embospheres to control active bleeding. The remaining two patients had large-sized (≥50?mm), centrally located renal pseudoaneurysms treated with thrombin?±?coils. Technical success with immediate bleeding cessation was achieved in all patients. There were no procedure-related deaths or complications (mean follow-up, 23.5 (range, 1–67) months).

Conclusions

Treatment of renal pseudoaneurysms using endovascular approach is a relatively safe and viable option regardless of location (central or peripheral) and size of the lesions with minimal renal parenchymal sacrifice.     

Endovascular management of carotid-cavernous fistulas

Objective To investigate endovascular treatment of traumatic direct carotid-cavernous fistulas （CCF） and their complications such as pseudoaneurysms. Methods： Over a five-year period, 22 patients with traumatic direct CCFs were treated endovascularly in our institution. Thirteen patients were treated once with the result of CCF occluded, 8 twice and 1 three times. Treatment modalities included balloon occlusion of the CCF, sacrifice of the ipsilateral internal carotid artery with detachable balloon, coll embolization of the cavernous sinus and secondary pseudoaneurysms, and covered-stem management of the pseudoaneurysms. Results All the direct CCFs were successfully managed endovascularly. Four patients developed a pseudoaneurysm after the occlusion of the CCF with an incidence of pseudoaneurysm formation of 18.2% （4/22）. A total number of 8 patients experienced permanent occlusion of the ICA with a rate of ICA occlusion reaching 36.4% （8/22）. Followed up through telephone consultation from 6 months to 5 years, all did well with no recurrence of CCF symptoms and signs. Conclusion Traumatic direct CCFs can be successfully managed with endovascular means. The pseudoaneurysms secondary to the occlusion of the CCFs can be occluded with stent-assisted coiling and implantation of covered stents.     

Anatomy of the Sinoatrial Nodal Branch in Korean Population: Imaging with MDCT

Objective

To evaluate, on a retrospective basis, the anatomic characteristics of the arterial supply to the sinoatrial node (SAN) in the Korean population using an ECG-gated multi-detector CT (MDCT).

Materials and Methods

The electrocardiographic-gated MDCTs of 500 patients (258 men and 242 women; age range, 17-83 years; mean age, 58.6 ± 12.04 years) were analyzed retrospectively. In each case, the SAN artery (arteries) was named according to a special nomenclature with regard to origin, course, and termination.

Results

A total of 516 SAN arteries were visualized in 496 patients. The SAN was supplied by a single artery in 476 (96.4%) cases and by 2 arteries in 18 (3.6%) cases. The SAN originated from the right coronary artery in 265 (53.4%) cases and from the left circumflex in 213 (43%) cases.

Conclusion

This study can provide basic data on variations of the SAN artery in the Korean population.     

Endovascular management of iatrogenic renal arterial lesions and clinical outcomes

PURPOSE

We aimed to evaluate iatrogenic renal arterial lesions, including pseudoaneurysm, arteriovenous fistula, and arteriocaliceal fistula, their management by endovascular embolization, and the clinical results.

METHODS

Fifty-five patients (forty males, fifteen females) with a median age of 40 years (range, 8–85 years), who underwent endovascular embolization of iatrogenic renal arterial lesions between March 2003 and December 2013 were included in this retrospective study. Types of iatrogenic lesions and details of embolization procedures were reported. Estimated glomerular filtration rate (eGFR), renal function tests, hemoglobin, and hematocrit levels before and after embolization were recorded and compared.

RESULTS

Median follow-up was 24 months. We identified 53 pseudoaneurysms, 30 arteriovenous fistulas, and 11 arteriocaliceal fistulas in 55 patients, after percutaneous nephrolithotomy (n=26), renal biopsy (n=21), nephrostomy (n=3), renal surgery (n=3), and extracorporeal shock wave lithotripsy (n=2). Median number of pseudoaneurysms was 1 (range, 1–4) with a median size of 7 mm (range, 1.5–35 mm). Fifty-one patients underwent coil embolization. Median number of coils was 5 (range, 2–21) and median renal parenchymal loss was 5% (range, 1%–50%). There were no significant differences between pre- and postoperative eGFR and serum parameters.

CONCLUSION

Iatrogenic renal arterial lesion can be a life threatening condition. Superselective coil embolization is a safe, minimally invasive treatment option with minimal renal parenchymal loss and without significant change in renal function.Iatrogenic renal arterial lesions including pseudoaneurysm (PA), arteriovenous fistula (AVF), and arteriocaliceal fistula (ACF) are rare, but life-threatening conditions (1). The chief symptom usually includes macroscopic hematuria (2, 3). Catheter angiography is the gold standard for both diagnosis and treatment (1).Previous studies have evaluated the iatrogenic renal arterial lesions following partial nephrectomy (1, 3–7), but there were only a few studies on iatrogenic renal arterial lesions following any iatrogenic renal interventions (2). In the present study, to the best of our knowledge, we report the largest series of iatrogenic renal arterial lesions following various renal interventions such as biopsy, percutaneous nephrolithotomy (PCNL), percutaneous nephrostomy, and partial nephrectomy. We focused on clinical presentations, imaging findings, management, and outcomes.     

Prehospital stroke diagnostics based on neurological examination and transcranial ultrasound

Background

Transcranial color-coded sonography (TCCS) has proved to be a fast and reliable tool for the detection of middle cerebral artery (MCA) occlusions in a hospital setting. In this feasibility study on prehospital sonography, our aim was to investigate the accuracy of TCCS for neurovascular emergency diagnostics when performed in a prehospital setting using mobile ultrasound equipment as part of a neurological examination.

Methods

Following a ‘911 stroke code’ call, stroke neurologists experienced in TCCS rendezvoused with the paramedic team. In patients with suspected stroke, TCCS examination including ultrasound contrast agents was performed. Results were compared with neurovascular imaging (CTA, MRA) and the final discharge diagnosis from standard patient-centered stroke care.

Results

We enrolled ‘232 stroke code’ patients with follow-up data available in 102 patients with complete TCCS examination. A diagnosis of ischemic stroke was made in 73 cases; 29 patients were identified as ‘stroke mimics’. MCA occlusion was diagnosed in ten patients, while internal carotid artery (ICA) occlusion/high-grade stenosis leading to reversal of anterior cerebral artery flow was diagnosed in four patients. The initial working diagnosis ‘any stroke’ showed a sensitivity of 94% and a specificity of 48%. ‘Major MCA or ICA stroke’ diagnosed by mobile ultrasound showed an overall sensitivity of 78% and specificity of 98%.

Conclusions

The study demonstrates the feasibility and high diagnostic accuracy of emergency transcranial ultrasound assessment combined with neurological examinations for major ischemic stroke. Future combination with telemedical support, point-of-care analysis of blood serum markers, and probability algorithms of prehospital stroke diagnosis including ultrasound may help to speed up stroke treatment.     

Percutaneous ultrasound-guided thrombin injection for the treatment of iatrogenic femoral artery pseudoaneurysms

Purpose

To audit our experience with ultrasound-guided thrombin injection for the treatment of iatrogenic femoral artery pseudoaneurysms.

Methods

A retrospective study of 85 consecutive patients undergoing percutaneous ultrasound-guided thrombin injection of post-catheterization femoral pseudoaneurysms during the period January 2002 to May 2007.

Results

Pseudoaneurysms had a mean maximum diameter of 3.3 cm (range 1.0-7.6 cm) and a mean neck width of 3.4 mm (range 1.0-7.0 mm). No statistically significant correlation existed between maximum diameter and neck width (Kendall's rank correlation tau b = −0.09, p = 0.5). The median dose of thrombin injected was 425 U (range 100-1500 U). The procedure resulted in complete sac thrombosis in 81 (95%) patients. Seventy-nine pseudoaneurysms thrombosed immediately after one injection, whereas two required a second thrombin injection. There were no procedural complications. The maximum diameter of the pseudoaneurysm was predictive of procedural success (Wilcoxon's rank sum test, p = 0.001) and of the 5 patients with a pseudoaneurysm measuring ≥6 cm, ultrasound-guided thrombin injection was unsuccessful in 4 (4/5 versus 0/80, p < 0.0001, Fisher's exact test). Three of these necessitated implantation of a stent-graft, whereas one required repeated thrombin injection and coil placement. In contrast, the pseudoaneurysm neck width did not seem to relate to the success of the procedure.

Conclusion

Percutaneous ultrasound-guided thrombin injection of is a quick, effective and safe treatment for iatrogenic femoral pseudoaneurysms. For larger pseudoaneurysms, although it is worth attempting more than one thrombin injection, endovascular repair may eventually be required.     

Aortic Branch Artery Pseudoaneurysms Associated with Intramural Hematoma: When and How to Do Endovascular Embolization

Purpose

To describe when and how to perform endovascular embolization of aortic branch artery pseudoaneurysms associated with type A and type B intramural hematoma (IMH) involving the descending thoracic and abdominal aorta (DeBakey I and III) that increased significantly in size during follow-up.

Materials and Methods

Sixty-one patients (39 men; mean ± standard deviation age 66.1 ± 11.2 years) with acute IMH undergoing at least two multidetector computed tomographic examinations during follow-up for 12 months or longer were enrolled. Overall, 48 patients (31 men, age 65.9 ± 11.5) had type A and type B IMH involving the descending thoracic and abdominal aorta (DeBakey I and III).

Results

Among the 48 patients, 26 (54 %; 17 men, aged 64.3 ± 11.4 years) had 71 aortic branch artery pseudoaneurysms. Overall, during a mean follow-up of 22.1 ± 9.5 months (range 12–42 months), 31 (44 %) pseudoaneurysms disappeared; 22 (31 %) decreased in size; two (3 %) remained stable; and 16 (22 %) increased in size. Among the 16 pseudoaneurysms with increasing size, five of these (three intercostal arteries, one combined intercostobronchial/intercostal arteries, one renal artery), present in five symptomatic patients, had a significant increase in size (thickness >10 mm; width and length >20 mm). These five patients underwent endovascular embolization with coils and/or Amplatzer Vascular Plug. In all patients, complete thrombosis and exclusion of aortic pseudoaneurysm and relief of back pain were achieved.

Conclusion

Aortic branch artery pseudoaneurysms associated with type A and type B IMH involving the descending thoracic and abdominal aorta (DeBakey I and III) may be considered relatively benign lesions. However, a small number may grow in size or extend longitudinally with clinical symptoms during follow-up, and in these cases, endovascular embolization can be an effective and safe procedure.     

Intra-arterial high signals on arterial spin labeling perfusion images predict the occluded internal carotid artery segment

Purpose

Arterial spin labeling (ASL) involves perfusion imaging using the inverted magnetization of arterial water. If the arterial arrival times are longer than the post-labeling delay, labeled spins are visible on ASL images as bright, high intra-arterial signals (IASs); such signals were found within occluded vessels of patients with acute ischemic stroke. The identification of the occluded segment in the internal carotid artery (ICA) is crucial for endovascular treatment. We tested our hypothesis that high IASs on ASL images can predict the occluded segment.

Methods

Our study included 13 patients with acute ICA occlusion who had undergone angiographic and ASL studies within 48 h of onset. We retrospectively identified the high IAS on ASL images and angiograms and recorded the occluded segment and the number of high IAS-positive slices on ASL images. The ICA segments were classified as cervical (C1), petrous (C2), cavernous (C3), and supraclinoid (C4).

Results

Of seven patients with intracranial ICA occlusion, five demonstrated high IASs at C1–C2, suggesting that high IASs could identify stagnant flow proximal to the occluded segment. Among six patients with extracranial ICA occlusion, five presented with high IASs at C3–C4, suggesting that signals could identify the collateral flow via the ophthalmic artery. None had high IASs at C1–C2. The mean number of high IAS-positive slices was significantly higher in patients with intra- than extracranial ICA occlusion.

Conclusion

High IASs on ASL images can identify slow stagnant and collateral flow through the ophthalmic artery in patients with acute ICA occlusion and help to predict the occlusion site.