[Inflammatory gastrointestinal diseases in children : Radiological diagnosis]. / Entzündliche gastrointestinale Erkrankungen bei Kindern : Radiologische Diagnose.

BACKGROUND/CLINICAL ISSUE: Inflammatory bowel diseases are frequently seen in the clinical routine of a pediatric radiologist. The timely diagnosis of inflammatory bowel diseases in children is particularly important in acute cases. STANDARD RADIOLOGICAL METHODS/METHODOLOGICAL INNOVATIONS: This nonsystematic article intends to give an overview of the radiologic imaging methods for the diagnosis and work-up of pediatric patients with inflammatory bowel diseases. PERFORMANCE: Ultrasound imaging is an important basis tool in pediatric clinical practice. However, sensitivity and specificity depends on the experience of the operator. Cross-sectional imaging modalities in pediatric patients with inflammatory bowel disease are performed only in exceptional cases when clinically justified. Dedicated computed tomography (CT) protocols for children are indispensable to lower radiation dose. ACHIEVEMENTS: Knowledge about particularities in inflammatory bowel diseases in pediatric patients and a rational approach to the use of radiological investigations in order to prevent the harmful effects of ionizing radiation are indispensable in dedicated pediatric imaging departments. PRACTICAL RECOMMENDATIONS: From a radiation-hygiene point of view, the clinical application of ultrasound imaging should be favored in the work-up of pediatric patients with inflammatory bowel diseases. Knowledge about advanced imaging procedures is essential particularly in imaging departments specialized in pediatric radiology.

Posttraumatic extracranial aneurysm of the internal carotid artery: combined endovascular treatment with coils and stents.

We report a case of a posttraumatic extracranial pseudoaneurysm of the internal carotid artery that was treated successfully via embolization with Guglielmi detachable coils and placement of a Wallstent after surgical repair failed.

Complications in endoluminal repair of abdominal aortic aneurysms.

In this review the technical and systemic complications occurring during endoluminal repair of abdominal aortic aneurysms are summarized. According to the data in the literature the technical success-rate of the endoluminal procedure should be >90% and the overall complication-rate <10%. It should be differentiated between complications which have an adverse effect on the outcome of the procedure, and technical problems, which complicate the procedure but do not affect the outcome. The majority of the technical problems can be solved endoluminally. The 30-day mortality rate should be in the same range as elective open surgical repair. One major factor influencing the immediate results is the experience of the interventional team.

[Treatment of malignant and benign biliary obstructions with metal stents]. / Behandlung maligner und benigner biliärer Obstruktionen mit Metallstents.

The palliative treatment of malignant biliary tract obstructions using a metal stent is now an established procedure in clinical practice. An endoscopic, transpapillary approach is the first choice for implantation of the stent. If it is not possible to insert the stent in this way, which is often the case with high obstructions, a percutaneous approach is chosen. It appears to be beneficial to use a metal stent with a fine-meshed net such as, for example, the Wall stent. Metal stents have a higher patency rate than plastic stents so that the primary choice of a metal stent is justified. Coated stents have not yet shown any major advantages. In cases of stent occlusion, the coaxial implantation of a plastic stent seems to be the most efficient. In cases of benign biliary tract stenoses, a metal stent should only be implanted after a careful evaluation of all possible surgical modalities and exploitation of balloon dilatation and long-term splinting methods.

[Pelvic artery embolization in gynecological bleeding]. / Beckenarterienembolisationen bei gynäkologischen Blutungen.

The most common reasons for gynecological bleeding are pregnancy-related disorders, fibroids of the uterus, and gynecological malignancies. Transarterial embolization is an effective treatment modality for gynecological bleeding regardless of its etiology. Depending on the underlying disease, a different technique of embolization is applied. In postpartal bleeding a temporary effect of embolization is desired, therefore gelatin sponge is used as embolizing agent. In fibroids and malignant tumors the effect should permanent, therefore PVA particles are used. Regardless the etiology, the technical and clinical success of transarterial embolization is at least 90 %. In nearly every patient a post-embolization syndrome can be observed, represented by local pain and fever. This post-embolization syndrome usually does not last longer than 3 days. If embolization is performed with meticulous attention to angiographic technique and handling of embolic material, ischemic damage of adjacent organs is rarely observed. Transarterial embolization should be an integrative modality in the treatment of gynecological bleeding.

[Clinical experiences with the transjugular intrahepatic portocaval shunt (TIPS)]. / Klinische Erfahrungen mit dem transjugulären intrahepatischen portokavalen Shunt (TIPS).

Twenty-five patients with liver cirrhosis and portal hypertension were admitted for creation of a transjugular intrahepatic portosystemic shunt (TIPS). The procedure was successful in 22 patients (technical success 88%). The mean portal pressure gradient was lowered from 24.5 mmHg before to 11.4 mmHg after TIPS. Two early and three late occlusions were observed (primary patency rate 78%). The rate of secondary interventions was 41%. Five times a hepatic vein stenosis was dilated and stented, two times an occluded shunt was recanalized, two times a new shunt was created parallel to an occluded (secondary patency rate within a maximum of 16 months 95%). In two patients sepsis occurred which was effectively treated with antibiotics, two patients died shortly after TIPS due to hepatorenal syndrome and hepatic failure, respectively. There was no recurrent bleeding. Two patients developed hepatic encephalopathy; both improved after protein restriction. The authors conclude that TIPS is an alternative procedure to shunt surgery, especially for patients who cannot benefit from sclerotherapy.

[The value of different spiral CT phases in the detection of liver metastases]. / Der Wert unterschiedlicher Spiral-CT-Phasen in der Suche nach Lebermetastasen.

PURPOSE: To assess the value of the non-contrast phase (NCP), hepatic-arterial phase (HAP) and portal-venous phases (PVP) for the detection of liver metastases by spiral CT. METHODS: In order to detect liver metastases, 119 patients (58 women, 61 men; mean age: 62 years) underwent triphasic spiral CT (8 mm collimation, 12 mm table increment/rotation, 7 mm reconstruction increment). NCP, HAP (20 s delay) and PVP (70 s delay) scans were acquired (contrast medium injection rate: 4 ml/s). CT analysis comprised independent evaluation of the three scan series for detection and conspicuity of liver metastases (conspicuity score: 0 = not visible, 1 = barely visible, 2 = clearly visible, 3 = distinctly visible). RESULTS: In 83 of the 119 patients, 478 liver metastases were detected (110 hypervascular and 368 hypovascular lesions). 285 (60 %) metastases were detected on NCP scans. Significantly more lesions were seen on HAP (n = 375, 78 %) and on PVP (n = 428, 90 %). No lesion was detected on NCP studies alone. For all detected metastases, mean conspicuity was 1.2 +/- 0.4 on NCP, 1.8 +/- 0.8 on HAP and 2.2 +/- 0.8 PVP. Hypervascular lesions were best seen on HAP with a conspicuity score of 2.0 +/- 0.8 versus 1.3 +/- 0.5 on NCP and 1.5 +/- 0.8 on PVP. Hypovascular lesions reached the highest conspicuity on PVP with 2.4 +/- 0.8 versus 1.2 +/- 0.4 on NCP and 1.7 +/- 0.7 on HAP. CONCLUSION: For detection of liver metastases with spiral CT, contrast series seem to be sufficient. For tumors likely to seed hypervascular metastases, HAP scans should be applied in addition to the PVP.

[Percutaneous recanalization of pelvic artery occlusions--fibrinolysis, PTA, stents]. / Perkutane Rekanalisation von Beckenarterienverschlüssen--Fibrinolyse, PTA, Stents.

In 42 patients with symptomatic chronic iliac artery occlusions with a length of 2-15 cm (mean 4.3 cm), percutaneous recanalization was attempted. The study population was divided into 2 groups: Group I (n = 17) is a retrospective control group, the patients were treated with fibrinolysis (FL) and percutaneous transluminal angioplasty (PTA). In group II (n = 25) the patients were treated according to a prospective protocol including FL, PTA and placement of endovascular self-expandable stents. The recanalization rate for Group I and II together was 83% (35/42). FL was effective in 47%, in 53% the recanalization was performed mechanically only. The patency rate in Group I during a maximum of 69 months was 67%, in Group II, in which residual stenoses were treated with stents, 100% during max. 18 months. Obviously stents help to improve the results after percutaneous recanalization of iliac artery occlusions significantly.

[Endoluminal therapy of infrarenal aortic aneurysms with the Talent system--initial experiences with a new endoprosthesis]. / Endoluminale Therapie infrarenaler Aortenaneurysmen mit dem Talent-System--Erste Erfahrungen mit einer neuen Endoprothese.

PURPOSE: To report the early clinical experience with the Talent stent-graft system in the treatment of infrarenal aortic aneurysms. MATERIALS AND METHODS: The study group comprised 15 males aged from 51-79 years. A bifurcated Talent stent-graft was implanted in 9 patients with type B or C aneurysms, a tube graft in 6 patients with a type A aneurysm. The stent-grafts were introduced via a surgical femoral cut-down, for a bifurcated graft a bilateral surgical access was needed. All procedures were performed as teamwork by radiologists and vascular surgeons under general anaesthesia in the angiography suite. RESULTS: Primary and secondary technical successes were 80 and 86%, respectively. Technical failures were due to access site problems (n = 1; elective open repair), malpositioning of the prosthesis (n = 1; immediate conversion to open surgery), and primary distal leakage (n = 1; elective occlusion by means of distal stent-graft extension). One patient died 15 days after an uneventful stent-graft insertion (30-day mortality 6%). No complications were observed during a mean follow-up period of 7.8 months. The aneurysmal diameter decreased in 6 patients and remained unchanged in the others. CONCLUSIONS: The Talent system revealed satisfactory early results which are comparable to competitive stent-graft systems. An advantage of this stent-graft device is the availability in a wide range of dimensions. A major disadvantage is the large introducer system (french size 22-27).

[Metallic mesh endoprosthesis and intraluminal high dose rate 192Ir brachytherapy in the palliative treatment of malignant bile duct obstruction. Initial results]. / Metallgeflecht-Endoprothese und intraluminare High-dose-rate-192Iridium-Brachytherapie zur palliativen Behandlung maligner Gallengangsobstruktionen. Erste Erfahrungen.

Since December 1989, 9 patients with inoperable malignant biliary tract obstruction were treated palliatively by a combined modality treatment consisting of placement of a permanent biliary endoprosthesis followed by intraluminal high dose-rate 192Ir brachytherapy. A dose of 10 Gy was delivered in a hyperfractionated schedule at the point of reference in a distance of 7.5 mm of centre of the source. External small field radiotherapy (50.4 Gy, 1.8 Gy per day, 5 fractions per week) was also given in six cases (M/O, Karnofsky greater than 60%). In 9/9 cases an unrestrained bile flow and an interruption of pruritus was achieved, in 78% (7/9) of cases the duration of palliation was as long as the survival time (median survival time 7.5 months).

[Indications for MIBG scintigraphy in the diagnosis of neuroblastoma]. / Indikationen zur MIBG-Szintigraphie in der Neuroblastomdiagnostik.

The significance and indications of MIBG scintigraphy are critically assessed. The results are compared with the results of whole-body bone scintigraphy, computed tomography (CT) and magnetic resonance tomography (MRT), and are related to values of catecholamine metabolites in 24-h urines. In our patients (10 histologically proven cases) MIBG scintigraphy turned out to be most useful in tumor follow-up. In contrast, the significance was much lower in primary tumor diagnosis and tumor staging as the exact primary diagnosis was established by other means such as CT, MRT, MDP whole-body scan, urine chemistry and bone marrow biopsy in all cases. MIBG scintigraphy in diagnostic imaging of neuroblastoma is an additive diagnostic tool and is called for in (1) tumour follow-up (progress, recurrencies, metastases); (2) primary diagnosis if the primary tumour has not been localized by means of CT or MRT; and (3) tumour staging to differentiate stage IV disease from lower stages as long as stage IV disease has not been established by bone-marrow biopsy or MDP whole-body scan.

Endovascular stentgraft infection--a life-threatening complication.

The implantation of covered stents or stentgrafts has increased greatly in the last few years for the endovascular reconstruction of arterial aneurysms. We report of three patients experiencing severe septic complications after stentgraft implantation. Endovascular stentgraft infection is a serious complication with high morbidity and mortality. General antibiotic prophylaxis seems to be indicated when implanting stentgrafts.

[Transposition of the subclavian artery with endovascular stent graft implantation for therapy of acute type B aortic dissection]. / Die Transposition der Arteria subclavia mit endovaskulärer Stentgraft-Implantation zur Therapie der akuten Aortendissektion Typ B.

We report about a patient with a thoracic aneurysm caused by an acute type-B dissection. Due to the concomitant affections the risk of surgery was distinctly increased, the reconstruction was performed endo vascular by stentgraft implantation (Talent, World Medical Systems, Sunrise FL) after transposition of the left subclavian artery to create a sufficient neck for the proximal stent placement. Endoluminal treatment seems to be a promising, less invasive alternative method in the treatment of acute aortic dissections.

Results and complications in endovascular treatment of abdominal aortic aneurysms--a single center experience.

Between September 1996 and February 2000 five female and 62 male patients with an abdominal aortic aneurysm, requiring therapy, underwent endoluminal treatment. Their age ranged from 51 to 81 years (mean 72 years). Preoperative evaluation was done with spiral computed tomography (CT) and angiography. All procedures were performed under general anesthesia in a radiologically adapted operating room. Postoperative complications occurred in 28.4%. The total conversion rate was 13.4%, the 30-day lethality rate was 1.4%. During the mean follow-up of 15.1 months 19 secondary interventions were necessary in 13 patients. The results presented in this study do not justify the wide use of this method and indicate a stricter form of patient selection.

Flat detector angio-CT following intra-arterial therapy of acute ischemic stroke: identification of hemorrhage and distinction from contrast accumulation due to blood-brain barrier disruption.

BACKGROUND AND PURPOSE: Flat panel detector CT in the angiography suite may be valuable for the detection of intracranial hematomas; however, abnormal contrast enhancement frequently mimics hemorrhage. We aimed to assess the accuracy of flat panel detector CT in detecting/excluding intracranial bleeding after endovascular stroke therapy and whether it was able to reliably differentiate hemorrhage from early blood-brain barrier disruption. MATERIALS AND METHODS: Seventy-three patients were included for retrospective evaluation following endovascular stroke therapy: 32 after stent-assisted thrombectomy, 14 after intra-arterial thrombolysis, and 27 after a combination of both. Flat panel CT images were assessed for image quality and the presence and type of intracranial hemorrhage and BBB disruption by 2 readers separately and in consensus. Follow-up by multisection head CT, serving as the reference standard, was evaluated by a single reader. RESULTS: Conventional head CT revealed intracranial hematomas in 12 patients (8 subarachnoid hemorrhages, 7 cases of intracerebral bleeding, 3 SAHs plus intracerebral bleeding). Image quality of flat panel detector CT was considered sufficient in all cases supratentorially and in 92% in the posterior fossa. Regarding detection or exclusion of intracranial hemorrhage, flat panel detector CT reached a sensitivity, specificity, positive and negative predictive values, and accuracy of 58%, 85%, 44%, 91%, and 81%, respectively. Maximum attenuation measurements were not valuable for the differentiation of hemorrhage and BBB disruption. CONCLUSIONS: Flat panel CT after endovascular stroke treatment was able to exclude the rare event of an intracranial hemorrhage with a high negative predictive value. Future studies should evaluate the predictive value of BBB disruptions in flat panel detector CT for the development of relevant hematomas.

[Clinical application of flat-panel CT in the angio suite]. / Klinische Anwendung der Flachdetektor-CT im Angio-OP.

The introduction of flat-panel detectors in modern angiographic C-arm systems makes it possible to acquire CT-like images in the angiographic suite (flat-panel CT; FD-CT). In this review, after a short technical introduction of FD-CT including the discussion of the advantages and disadvantages of this new imaging modality, the most commonly and best evaluated indications for FD-CT will be described. FD-CT has become an important adjunctive imaging modality in neurointerventional procedures and embolizations, especially during liver embolization. Another attractive indication for FD-CT is musculoskeletal interventions. FD-CT may provide important additional information in complicated peripheral vascular interventions and stent-graft procedures. FD-CT has a broad spectrum of possible applications, which finally depends on the experience and innovative thinking of the operator. However, it has to be kept in mind that FD-CT causes additional radiation exposure. Roughly, it can be assumed that currently one FD-CT sequence causes at least the same radiation exposure as one spiral CT sequence of the corresponding body region.