Biomechanics applied to incisional hernia repair - Considering the critical and the gained resistance towards impacts related to pressure.

BACKGROUND: Incisional hernia repair is burdened with recurrence, pain and disability. The repair is usually carried out with a textile mesh fixed between the layers of the abdominal wall. METHODS: We developed a bench test with low cyclic loading. The test uses dynamic intermittent strain resembling coughs. We applied preoperative computed tomography of the abdomen at rest and during Valsalva's maneuver to the individual patient to analyze tissue elasticity. FINDINGS: The mesh, its placements and overlap, the type and distribution of fixation elements, the elasticity of the tissue of the individual and the closure of the abdominal defect-all aspects influence the reconstruction necessary. Each influence can be attributed to a relative numerical quantity which can be summed up into a characterizing value. The elasticity of the tissues within the abdominal wall of the individual patient can be assessed with low-dose computed tomography of the abdomen with Valsalva's maneuver. We established a procedure to integrate the results into a surgical concept. We demonstrate potential computer algorithms using non-rigid b-spline registration and artificial intelligence to further improve the evaluation process. INTERPRETATION: The bench test yields relative values for the characterization of hernia, mesh and fixation. It can be applied to patient care using established procedures. The clinical application in the first ninety-six patients shows no recurrences and reduced pain levels after one year. The concept has been spread to other surgical groups with the same results in another fifty patients. Future efforts will make the abdominal wall reconstruction more predictable.

Strengths and limitations of coronary angiography with turbo high-pitch third-generation dual-source CT.

AIM: To define practical limitations of diagnostic image quality for recently introduced turbo high-pitch scan mode (THP) in third-generation dual-source computed tomography (CT). MATERIALS AND METHODS: Two hundred and twenty-nine consecutive patients undergoing CT coronary angiography were included in this retrospective single-centre analysis. A contrast-enhanced volume dataset was acquired in THP. Image quality of coronary segments was classified as diagnostic or non-diagnostic by three blinded readers. Segments were stated as non-diagnostic if at least one of three readers could neither exclude nor confirm significant stenoses. Multivariable logistic regression was used to assess relationships between number of non-diagnostic segments and common influencing factors. RESULTS: Median effective radiation dose was 0.6 (interquartile range [IQR], 0.4-0.8) mSv overall and 0.3 (IQR, 0.3-0.4) mSv in the 70 kV subgroup of this middle aged, predominantly pre-obese cohort (age: 61 [IQR, 52-67] years; body mass index [BMI]: 26 [IQR, 23-29] kg/m2) with a low-moderate median Agatston score (AS) 0 (IQR, 0-70). Diagnostic image quality was found in 98.1% of 3,678 coronary segments. AS was independently associated with diagnostic image quality (B=0.34; p=0.02), whereas heart rate, BMI, and presence of arrhythmia were not. The portion of diagnostic coronary segments decreased slightly in obese patients with heart rates >65 beats/min and dropped significantly in patients with an AS >600 (p=0.003). CONCLUSION: THP enables CT coronary angiography with minimal radiation exposure and is most appropriate in non-obese patients with stable sinus rhythm ≤65 beats/min and a calcium score ≤600.

[Non-occlusive mesenteric ischemia]. / Non-okklusive Darmischämie: Radiologische Diagnostik und Therapie.

The so-called non-occlusive disease (NOD) or non-occlusive mesenteric ischemia (NOMI) is a severe and life-threatening pathology. Even under optimal circumstances and standardised diagnostic and therapeutic procedures maximum survival rates do not exceed 50 %. The NOD is a pathology of the elder patient and its incidence rises with other comorbidities such as reduced cardiac output, diabetes and renal insufficiency. Induction of the disease with a severe vasoconstriction of the splanchnic vessels may be a simple cardiac decompensation, a frequent trigger however is a previous heart surgery with consecutive cardiac shock. Early diagnosis is difficult to conduct because of unspecific symptoms. Beside abdominal pain in awake patients, ileus or subileus is remaining the single acute symptom which could be also a consequence of a postoperative paralysis. Laboratory parameters such as leucocytosis and elevated lactat levels are often positive, but unspecific and the latter may be a delayed sign of progressive disease. The only sufficient method for diagnosis implicating a possible treatment option seems to be an immediate angiographic examination. Because of the disappointing results of a solitary surgical approach transarterial medication via catheter is indicated. Depending of the course of the disease only a combination of local mesenteric infusion of vasodilatory drugs and surgical resection of already necrotic bowel promises a successful therapeutic approach and better survival rates.

[Brain abscesses in diffusion-weighted imaging (DWI)--comparison to cystic brain tumors]. / Der Hirnabszess in der Diffusionswichtung und Unterschiede zum zystischen Hirntumor.

PURPOSE: The clinical usefulness of diffusion-weighted imaging (DWI) was evaluated in patients with brain abscesses in comparison to patients with cystic brain tumors. MATERIAL AND METHODS: Five patients with surgically confirmed brain abscesses underwent beside a brain MRI examination with contrast media application diffusion weighted imaging. Apparent diffusion coefficients (rADC) in three orthogonal diffusion gradient were calculated. The same protocol was used to examine 5 patients with cystic brain tumors. RESULTS: Showing an rADC of 0.33 x 10(-3)/mm(2)/s abscesses have a highly restricted diffusion in comparison to cystic brain tumors with an rADC of 1,67 x 10(-3)/mm(2)/s. CONCLUSION: Diffusion weighted imaging is a usefull diagnostic tool in the work up of brain abscesses.

Endovascular exclusion of thoracic aortic aneurysms: mid-term results of elective treatment and in contained rupture.

PURPOSE: The purpose is to present results of endovascular exclusion (stent-graft treatment) of aneurysms of the descending thoracic aorta both in elective cases and in emergencies. METHODS: Indications for stent-graft treatment were dependent on multislice angio-CT evaluation revealing a proximal neck of at least 10 mm between the left common carotid artery and the onset of aneurysm. All stent grafts were inserted in the operating room; 43 transfemoral, 2 transiliac. The stent grafts used were Corvita, Stenford, Vanguard, AneuRx, Talent, and Excluder. Deployment was achieved under fluoroscopic control, endoleaks were checked for with D S A on the operating table and postoperatively by angio-CT. Long-term follow-up consisted of evaluation with angio-CT after 6 and 12 months, and from there on once a year and with plain chest X-rays. Follow-up was achieved in all patients. RESULTS: Mean follow-up is 21 months (1-66); 30-day mortality is 3/45, no permanent neurologic deficit. Thirty patients were treated electively, 15 with contained rupture. Left subclavian artery overstenting proved to be necessary in 12 patients for proper proximal sealing of the aneurysm, type I endoleaks were observed in 10 patients, one early conversion, 7 proximal extension cuffs, one sealed spontaneously, one still at risk. Among patients where LSA had been overstented only one wanted a transposition, all others did well without left-hand ischemia or subclavian steal syndrome. CONCLUSION: Endovascular treatment is less invasive and has reasonable mortality and morbidity but is limited to well-defined morphologies. Mid-term results are promising but it has to be observed whether these will translate into long-term durability.

Treatment of thoracoabdominal aortic aneurysms with a combined endovascular and surgical approach.

AIM: The conventional approach for the repair of thoracoabdominal aneurysms remains complex and demanding and is associated with substantial morbidity and mortality. Moreover, in cases of reoperation the impact can be dramatic either in survival or in quality of life of the patients, albeit the use of adjuncts. A combined endovascular and surgical approach with retrograde perfusion of visceral and renal vessels has been realized in order to minimize intraoperative and postoperative complications. METHODS: Within an experience of 231 aortic stent-grafts between 1995-2000, 4 of the patients with thoracoabdominal aneurysms were treated with a combined endovascular and surgical approach. Three procedures were electively conducted and 1 on emergency basis. Two women, 59 and 68 years old, and 2 men, 68 and 73 years old (maximum aneurysm's diameter was 10, 6, 8 and 9 cm, respectively) were operated with the combined method (the first 2 patients had a previous open repair of a thoracoabdominal aneurysm). The surgical approach was executed in all patients without thoracotomy or re-do retroperitoneal exposure. Revascularization of renal, superior mesenteric (and celiac in 2 cases) arteries was accomplished via transperitoneal bypass grafting. Aneurysmal exclusion was performed by stent-graft deployment. RESULTS: The entire procedure was technically successful in all patients. The 1(st) patient was discharged 6 weeks after the operation, while the postoperative studies revealed the patency of the vessels and no evidence of leak or secondary rupture of the aneurysm; the patient died 3 months after the repair, due to rupture of an aneurysm of the ascending aorta. In the 2(nd) patient, 30 months after the operation, spiral-CT scanning revealed distinct shrinkage of the aneurysm, no graft migration or endoleak and patency of all revascularized vessels. The 3(rd) patient died on the 6th postoperative day due to multiorgan failure after having developed ischemic-related pancreatitis, albeit the successful combined repair. The 4(th) patient followed an uneventful course. No patient experienced any temporary or permanent neurological deficit. CONCLUSION: The combined endovascular and surgical approach is feasible, without cross-clamping of the aorta and with minimized ischemia time for renal and visceral arteries, and seems the appropriate strategy for high risk and previously operated, with a thoracoabdominal trans-diaphragmatic approach, patients.

Endovascular treatment in diseases of the descending thoracic aorta: 6-year results of a single center.

OBJECTIVE: The purpose of this study was to evaluate endovascular treatment in diseases of the descending thoracic aorta. MATERIAL AND METHODS: This study was designed as a single center's (university hospital) experience. Over a 6-year period (1995 to 2001), thoracic endografts were placed in 74 patients with a diseased descending thoracic aorta who were at high risk for conventional open surgical repair: 34 had atherosclerotic aneurysms, six had posttraumatic aneurysms, 14 had type B dissection with aneurysmal dilatation of the false lumen, 12 had isthmic transections from blunt trauma, five had thoracoabdominal aneurysms (treated with a combined procedure), two had aortic coarctation, and one had an aortobronchial fistula. Twenty-six procedures (35.1%) were conducted as emergencies, and 48 (64.9%) were elective. The feasibility of endovascular treatment and sizing of stent grafts were determined with preoperative spiral computed tomography and intraoperative angiography. RESULTS: Endovascular operations were completed successfully in all 74 patients; postprocedural conversion to open repair was necessary in three cases. The overall 30-day mortality rate was 9.5% (seven deaths). Temporary neurologic deficits developed in two patients; not one patient had permanent paraplegia. The primary endoleak rate was 20.3% (15 patients). The mean follow-up period was 22 months (range, 3 to 72 months). Five deaths occurred in the follow-up period, and three patients needed secondary conversion to open repair 2, 3, and 14 months after initial endografting. CONCLUSION: Endoluminal treatment in diseases of the thoracic descending aorta is feasible and may offer results as good as the open method.

[The contribution of MRI to the detection of endovascular aneurysm repair]. / Wertigkeit der MRT in der Erkennung von Leckagen nach endovaskulärer Aneurysmaausschaltung.

PURPOSE: Evaluation of MR-imaging in the follow-up of patients after endovascular repair of abdominal aortic aneurysms concerning detection of endoleaks. MATERIALS AND METHODS: In the postoperative follow-up after endovascular repair of aortic aneurysms, 10 consecutive patients (mean age: 68 years) were suspected to have an endoleak by helical CT and were scheduled for conventional angiography, preceded by supplemental MR-imaging to confirm or refute the diagnosis. The images of helical CT and MRI were evaluated by two independent readers concerning leak, feeding vessel and artifacts. RESULTS: The follow-up MRI was able to detect all endoleaks (type 1 endoleak, n = 7; type 2 endoleak, n = 3) compared to all but one detected by helical CT. Of the 10 patients with an endoleak, MR-angiography visualized the feeding vessel in 7 patients and CT in one patient. MRI did show fewer metal artifacts from the stent wire than CT. For the visualization of feeding vessels and endoleaks, MRA achieved statistically significant superiority. In a single case, helical-CT was not reliable because of strange metal artefacts after previous coil embolization. CONCLUSION: MRI is comparable to helical-CT in detecting endoleaks and superior to CT in demonstrating the anatomy of the feeding vessel after endovascular repair of aortic aneurysms. The major advantages are fewer artifacts after coil embolization and absent radiation exposure.

[Endoluminal stent-assisted management of acute traumatic aortic rupture]. / Endoluminale stentgestützte Versorgung der akuten traumatischen Aortenruptur.

INTRODUCTION: Open repair of traumatic descending aortic rupture in trauma patients is associated with a mortality rate of 15-20% and a risk of paraplegia of 5-10%. Stent grafts may decrease the morbidity and mortality of these procedures by reducing blood loss and aortic occlusion time. MATERIAL AND METHODS: Within an experience of 52 thoracic stent grafts between 1995 and 2000, eight men with acute traumatic descending aortic rupture were conducted as emergencies without delay. All patients had severe coinjuries and presented with acute onset of mediastinal hematoma due to periaortic bleeding. Successful stent deployment was performed in all eight patients, seven of them required one single stent and one required two stents; within the aortic arch all stents covered the origin of the left subclavian artery. RESULTS: All acute aortic ruptures were sealed successfully. One death occurred in hospital from multiorgan failure. There was no conversion to open repair. Not one patient's condition resulted in temporary or permanent paraplegia. One endoleak required treatment by overstenting. Two patients required secondary surgical procedures (iliac access complication and revascularisation of left subclavian artery). Mean follow-up was 11 months (1-21 months). Mid-term freedom from endoleak was monitored in all patients. CONCLUSION: The treatment of acute traumatic descending aortic rupture with an endovascular approach is feasible and safe and may offer the best means of therapy. The mortality rate and risk of paraplegia are low compared with the risks associated with open operations. Continued surveillance is essential.

Endovascular repair of aortic rupture due to trauma and aneurysm.

OBJECTIVES: to report a single centre experience with endovascular repair of the ruptured descending thoracic and abdominal aorta. DESIGN: prospective non-randomised study in a university hospital. MATERIAL AND METHODS: between 1995 and 2000, endovascular treatment was utilised for 231 aortic repairs; in 37 cases (16%) endografting was conducted on an emergency basis for 21 ruptured infrarenal aortic aneurysms, 15 ruptured descending thoracic aortic lesions, and 1 ruptured thoracoabdominal aortic aneurysm. The feasibility of endovascular treatment and the prostheses' size were determined, based on preoperative spiral CT and intraoperative angiography, both obtained in each patient. RESULTS: endografting was successfully completed in 35 patients (95%). Primary conversion to open repair was necessary in 2 patients (5%). Postoperative 30-day mortality rate was 11% (4 deaths). No patient developed postoperative temporary or permanent paraplegia. In 2 patients (5%) primary endoleaks required overstenting and in 6 patients (16%) secondary surgical interventions were required. Mean follow-up was 19 months (1-70 months); three deaths occurred within three months postoperatively (1-year survival rate 81+/-6%). In one case, secondary conversion to open repair was necessary 14 months postoperatively. CONCLUSION: the feasibility of endoluminal repair of the ruptured aorta has been demonstrated. Endoluminal treatment may reduce morbidity and mortality, and may in time become the procedure of choice in certain centres. However, further follow-up is required to determine the long-term efficacy.

Endovascular stent-graft placement versus conventional open surgery in infrarenal aortic aneurysm: a prospective study on acute phase response and clinical outcome.

BACKGROUND: For the treatment of aortic aneurysm, stent-graft implantation is an alternative method to open surgery. There is no study comparing both methods with regard to endotoxaemia, the acute phase cascade, and clinical outcome. METHODS: In this prospective study, we enrolled 40 patients (34 males, 6 females; mean age 72.1+/-7.5 [58-92] years) with infrarenal abdominal aortic aneurysm who underwent aortic surgery. Comparable groups of patients were treated with open (n=20) or endovascular (n=20) stent-graft implantation. To characterize the inflammatory response, plasma levels of endotoxin, endotoxin-neutralizing capacity (ENC), interleukin-6 (IL-6), C-reactive protein (CRP), and white blood cell count were determined. In all patients, measurements were performed on admission, skin suture, 4 h and from the first to fifth postoperative day. As parameters for the clinical outcome, we assessed daily temperature, lung function, pain, duration of postoperative hospital stay, and morbidity. Wilcoxon rank test was used for statistical analysis. RESULTS: In both groups, a significant increase of endotoxin plasma levels and a decrease of ENC was found already after skin incision. IL-6 levels peaked 4 h postoperatively in both groups, whereas CRP rose at the first postoperative day, reaching a maximum at day 2. Conventionally operated patients had significantly higher plasma levels of endotoxin, IL-6, and CRP and lower ENC during and after surgery than patients with stent-graft implantation. Moreover, patients with endovascular stent grafting had significant less postoperative pain, less restriction of total vital capacity, a shorter hospital stay, and a lower morbidity. CONCLUSIONS: Endovascular stent grafting of infrarenal aortic aneurysm seems to be superior not only in terms of the inflammatory response but also in overall clinical outcome.

Does a postimplantation syndrome following endovascular treatment of aortic aneurysms exist?

The postimplantation syndrome (PIS) is a weakly defined condition that has been observed following endovascular treatment of aortic aneurysms; the postulated criteria include significant leukocytosis, fever, and/or coagulation disturbances. Among the factors that are supposed to contribute to this syndrome are contact activation by the stent covering with consecutive endothelial activation. Associated clinical parameters of a PIS were perioperatively monitored in the postoperative phase in a total of 69 patients with infrarenal aortic aneurysms treated with Y-stent grafts. C-reactive protein (CRP)-levels, leukocyte concentrations, and body temperature curves were directly compared to those of 50 patients undergoing conventional transperitoneal aneurysm resection. A subgroup of 10 patients of the endovascular group was compared with 13 operated-on patients with regard to an ischemia-reperfusion syndrome of the lower extremities. The mediator determinations were performed on venous (femoral vein) as well as in systemic (arterial) blood samples. The incidence of temperature values above 38 degrees C was higher in patients following endovascular treatment (72%) compared to conventionally operated-on patients (28%). CRP levels were not significantly different within the first 8 post-operative days. During open surgery, significantly higher values for lactate and lower pH levels were observed (p<0.01), as well as higher 6 keto prostaglandin F1alpha (PGF1alpha) levels. There was a short peak of PGF1alpha during eventeration of the intestine during the operative procedure that could not be detected during endovascular manipulations. The clinical and biochemical parameters do not prove the presence of a PIS following endovascular treatment of aortic aneurysms. In contrast, during open surgery the unspecific inflammatory reaction is higher, but not long-lasting. In the future, the suggested phenomenon of a decreased antiinflammatory cytokine response during endovascular surgery needs to be further examined.

Thrombus formation in aortic endografts.

PURPOSE: To examine the incidence of intraprosthetic thrombotic deposits in aortic endografts. METHODS: Transfemoral implantation of tube or bifurcated stent-grafts was performed in 82 patients (75 men; average age 67.7 years, range 25-88) for treatment of aneurysms of the abdominal (n = 73) or thoracic (n = 9) aorta in a 3.5-year period. Patients underwent 3-phase helical computed tomographic (CT) examinations at 3-month intervals. The length and cross-sectional area of any thrombotic deposits were measured from axial and 3-dimensional CT images. RESULTS: Over a 12.1-month mean follow-up, intraluminal deposits of thrombotic material were observed in 19 (23.2%) patients, all with infrarenal endografts that were predominately of a bifurcated design. The first signs of thrombus formation occurred on average 7 months postoperatively (range 1 week to 20 months). In 16 patients, nonocclusive deposits of thrombotic material were seen in the aortic segment of the endograft; a graft limb was involved in 5 patients. Three graft limbs occluded owing to kinking; no thrombus was seen on CT scans taken prior to occlusion. In 3 cases the thrombotic deposits disappeared completely from the prosthesis lumen during follow-up. CONCLUSIONS: Based on this small experience, nearly 1 in 5 patients may experience some degree of intraluminal thrombus following endovascular treatment of aortic aneurysms. Whether the deposition of thrombus is influenced by the geometry of the aortic stent-graft or by flow conditions within the prosthetic lumen must be determined in future studies.

Intraoperative, perioperative and late complications with endovascular therapy of aortic aneurysm.

PURPOSE: To describe the incidence and management of the intraoperative, perioperative and late complications of endovascular aortic aneurysm repair. METHODS: Endovascular aneurysm repair was attempted in 130 patients between October, 1995 and January, 2000. Follow-up including computed tomography (CT) was performed in the immediate postoperative period and then at 3, 6, 9 and 12 months and biannually thereafter. The median follow-up period was 20 months. RESULTS: Intra- and perioperative problems occurred in 26 patients (20%). Conversion to open surgery was required in five cases (4%). The primary technical success rate was 86%. Three patients (2%) died within the first 30 postoperative days. Late problems occurred in 28 patients (26%). These included: endoleaks (type I: 5%; type II: 10%; type III: 1%) and limb occlusion (3%). The cumulative rate of freedom from secondary intervention was in the first 65 patients treated: 86% and 65% after 1 and 3 years, respectively, and in the last 65 patients: 90% at 1 year. CONCLUSIONS: Endovascular aneurysm repair is associated with a higher complication rate than open surgery.

Endovascular grafting of traumatic aortic aneurysms in contaminated fields.

PURPOSE: To evaluate the potential of endovascular stent-grafts to treat traumatic aortic lesions in contaminated areas. METHODS: Four patients (3 women; ages 26-78 years) underwent stent-grafting to repair an aortic rupture sustained in a motorcycle accident, aortic lacerations secondary to surgical treatment of spondylitis in 2 patients, and an aortobronchial fistula following surgical thoracic aortic repair 10 years earlier. Stent-grafts (2 Corvita, 1 Talent, and 1 Vanguard) were placed endoluminally into the infected areas via a transfemoral approach. Follow-up included erythrocyte sedimentation rate, white blood count, C-reactive protein, blood cultures, and computed tomography (CT). RESULTS: The stent-grafts were successfully placed in all cases and excluded the aortic lesion. Under supportive antibiotic therapy, inflammation parameters returned to normal. CT imaging showed no evidence of paraprosthetic infection, nor were there any other complications over a follow-up that ranged from 3 to 34 months. CONCLUSIONS: Endovascular therapy may be an alternative in the acute management of aortic ruptures in the setting of infection. Long-term results are required for definitive evaluation of the method.

Percutaneous techniques for managing maldeployed or migrated stents.

PURPOSE: To report our experience in the percutaneous management of dislocated endovascular stents. METHODS: During a 6-year period, 28 (2.7%) patients with a maldeployed or migrated endovascular stent (20 Palmaz, 5 Wallstent, 2 Memotherm, and 1 AVE) were recognized among 1021 patients undergoing noncardiac vascular stent procedures. Percutaneous stent management was performed using balloon catheters, gooseneck snares, grasping forceps, or additional stent implantation on the basis of the stent type, degree of expansion, mechanical characteristics, and location of the stent. RESULTS: Three stents that embolized into the pulmonary artery were left in situ, but percutaneous management was successful in 23 (92%) of the remaining 25 dislocated stents (12 venous and 13 arterial stents). Twelve stents were repositioned in an alternate, stable position or the primarily intended location; 4 stents were anchored by a second stent, and 7 stents were removed percutaneously. In the 2 failed cases, the stents were retrieved using a minor surgical procedure. There were 2 minor groin hematomas but no secondary complications during a median follow-up of 26.2 months (range 1-62). CONCLUSIONS: Percutaneous management of migrated or maldeployed endovascular stents is highly effective with few complications. On the basis of our findings, these techniques should be considered the therapy of choice.

Influence of treatment of type II leaks on the aneurysm surface area.

OBJECTIVE: to determine whether interventional treatment of type II endoleaks leads to a decrease in aneurysm surface area. MATERIAL AND METHOD: type II endoleaks were detected in a group of 14 male patients (median age: 70.2 years) following endovascular repair of a total number of 160 infrarenal aneurysms of the abdominal aorta. The surface area of the aneurysm was determined by computed tomography (CT) pre- and postoperatively and at subsequent follow-up examinations. If type II endoleaks were documented at CT, patients underwent treatment by means of coil embolisation. RESULTS: interventional treatment resulted in successful occlusion of type II endoleaks in eight patients. One of the cases exhibited spontaneous occlusion. Occlusion was associated with an average decrease in aneurysm surface area of 3.3 cm(2)( p =0.01). In one of these patients, treatment resulted in a temporary occlusion of the endoleak, also with associated decrease in aneurysm size. After recurrence of the type II endoleak, however, the patient experienced an increase in aneurysm surface area. In the remaining four patients the type II endoleaks persisted, resulting in a non significant increase in aneurysm surface area. CONCLUSION: only complete occlusion of endoleaks results in decrease in the size of the aneurysm sac. Because of endotension and the risk of rupture we favour an early interventional treatment of type II endoleaks.

Percutaneous retrieval of lost or misplaced intravascular objects.

OBJECTIVE: We report on our experience with percutaneous interventional techniques for retrieval of intravascular foreign bodies or repositioning of misplaced endovascular prostheses. MATERIALS AND METHODS: Over a period of 6 years, we attempted percutaneous treatment of intravascular foreign bodies in 45 patients. The 45 foreign objects consisted of 12 endovascular stents, 14 catheter fragments, 11 embolization coils, four guidewire fragments, three vena cava filters, and one cardiac valve fragment. Percutaneous extraction was performed using a combination of multipurpose catheters and nitinol snare loop or grasping forceps. Depending on their composition, misplaced or dislodged intravascular stents were either repositioned or percutaneously removed. RESULTS: Percutaneous intervention was successful in 41 (91.1%) of 45 patients. Of 38 patients on whom we performed percutaneous removal, the procedure was successful in 34 patients (89.5%), including 13 of the 14 patients with catheter fragments, all four of the patients with guidewire fragments, 10 of the 11 patients with misplaced or dislodged embolization coils, four of the five patients with misplaced or dislodged endovascular stents, and all three of the patients with misplaced or dislodged vena cava filters. The procedure was not successful in the one patient with a cardiac valve fragment. All seven of the percutaneous repositioning procedures we performed resulted in the endovascular stent being successfully repositioned in a stable intravascular position. Most of the retrieval procedures (77.7%) were performed using the nitinol snare as the primary instrument. No late complications were registered during the follow-up period, which ranged from 9 to 68 months (mean, 42.4 months overall). CONCLUSION: Percutaneous techniques for the extraction of intravascular foreign objects or for repositioning of dislocated endovascular stents are highly effective with a low rate of complications and should always be the primary method of choice.

Common bile duct stenosis in complicated chronic pancreatitis.

BACKGROUND: Common bile duct stenosis (CBDS) is one of the most frequent and serious complications in patients with chronic pancreatitis. Due to improved diagnostic tools, the frequency of CBDS seems to occur more frequently, nevertheless the prevalence varies widely because of different selection criteria. METHODS: Between April 1982 and October 1996, 323 patients with chronic pancreatitis and inflammatory mass in the head of the pancreas (IMH) (286 patients) or CBDS alone (37 patients) were operated. Patients' data including US, CT, ERCP, endocrine and exocrine function tests were documented prospectively. Dividing patients into groups with and without CBDS, clinical data were comparable concerning distribution of sex, age, etiology of the disease and clinical feature. RESULTS: Regarding the subgroup of 286 patients with inflammatory mass in the head of the pancreas (IMH), 154 patients (51%) showed radiological proved CBDS; out of this group, 82 patients (57%) revealed cholestasis and 37 patients (26%) had one or several periods of jaundice. By means of ERCP, 104 patients (72%) revealed short stenosis of the common bile duct (CBD) (<2 cm). No significant differences could be found in terms of morphologic alterations like pancreatic main duct stenosis, pseudocysts, duodenum stenosis, vascular obstruction. Ten patients (7%) in the group with CBDS and 13 patients (9%) in the group without CBDS had cancer in the pancreatic head. Concerning the endocrine function, the group of patients with CBDS had a significantly elevated rate of impaired glucose metabolism (IGT or IDDM) compared to the group without CBDS (60% versus 38%; P < 0.003). These results demonstrate that patients with IMH bear the risk of developing a stenosis of the CBD even before they become symptomatic with cholestasis or jaundice. CONCLUSION: Due to the elevated morbidity and the significantly deteriorated endocrine function, patients of this group are candidates for early surgical treatment.