Dieter Liermann

Brachytherapy with iridium-192 HDR to prevent from restenosis in peripheral arteries. An update.

The use of stents does not appreciably improve restenosis (usually resulting from intimal hyperplasia) as compared to percutaneous transluminal angioplasty (PTA) alone. The development of small-caliber probes for afterloading therapy in the biliary tract allowed us to use these for therapy in the vascular system. Using a special 9 F catheter, exact measurement of the length of the stented vascular segment and of the insertion length of the afterloading probe could be reproducibly performed. We used a Nucletron (Micro) Selectron HDR planning system version 10.10 for exact calculation, monitoring, and control of the afterloading procedure. Our source was iridium 192 (10 Ci) with a diameter of 1.1 mm. The program controls and monitors the insertion and removal of the iridium probe from the source into the special catheter through to the tip, and monitors the irradiation duration. The exposure time was around 200 seconds for a surface dose of 12 Gy.To date, a total of 40 patients have been treated with endovascular afterloading. All patients suffered from clinically relevant reocclusions or restenoses in stented vascular segments of the superficial femoral artery following successful PTA or laser treatment, within 6 to 8 months after the last therapy. In all patients it was possible to perform re-PTA treatment without remaining residual stenoses in the stented region. The additional time required as compared to PTA alone was approximately 45 minutes with most of this time spending for transportation between the cath lab and afterloading room.The follow-up period of the 40 patients ranged from 4 months to 7 1/2 years. In 33 patients, there was no deterioration of the clinical stage and no restenosis. One patient suffered from an acute thrombosis approximately 3 months after stent implantation, another patient had a stenosis 3 cm above the stented vascular segment 12 months after irradiation treatment. Follow-up examinations have revealed no evidence of nerve lesions following irradiation therapy. The tissue, surrounding the artery showed no change following irradiation therapy, either in the CT, color-coded Doppler, endovascular ultrasonic scan or MRI. No complaints of discomfort were reported during or after irradiation. With the exceptions mentioned above, there was no evidence of any complications.ZusammenfassungDer Gebrauch von Stents hat nicht wesentlich die Problematik der Restenose (meist Intimahy-perplasie) im Vergleich zur alleinigen perkutanen transluminalen Angioplastie (PTA) gelöst. Die Entwicklung dünner Drähte zur Afterloading-Therapie im Gallengang hat uns Gelegenheit gegeben, diese auch zur endovaskulären Bestrahlung zu nutzen. Mit Hilfe eines speziellen 9-F-Katheters können exakte Messungen der Länge des gestenteten Gefäßsegments und der Einführlänge des Afterloading-Drahtes reproduzierbar durchgeführt werden. Wir verwendeten ein Nucletron-(Micro-)Selectron-HDR-Gerät zur Therapieplanung (Version 10.10), exakten Berechnung, Monitoring und zur Kontrolle des Afterloadings. Die von uns verwendete Strahlenquelle war Iridium 192 (10 Ci) mit einem Durchmesser von 1,1 mm. Das Programm kontrolliert und überwacht das Einführen und Zurückbringen des Iridium-drahtes und auch die Bestrahlungszeit. Diese beträgt etwa 200 Sekunden für eine Oberflächendosis von 12 Gy.Bis heute haben wir insgesamt 40 Patienten mit endovaskulärem Afterloading behandelt. Alle Patienten litten an klinisch relevanter Restenose bzw. Reverschluß in den gestenteten Gefäßsegmenten der Arteria femoralis superficialis nach primär erfolgreicher PTCA bzw. Laserbehandlung. Die Bestrahlung fand sechs bis acht Monate nach der letzten Intervention statt. Bei einem Patienten konnten wir eine erfolgreiche Re-PTA ohne Residualstenose im Stentbereich durchführen. Die zusätzliche Zeit, die für die Nachbestrahlung erforderlich ist, beträgt etwa 45 Minuten, der größe Teil wird für den Transport vom Katheterlabor in die Strahlentherapieabteilung benötigt.Die Nachbeobachtungszeit dieser 40 Patienten liegt zwischen vier Monaten und siebeneinhalb Jahren. Bei 33 Patienten trat keine Verschlechterung des klinischen Stadiums bzw. keine Restenose ein. Ein Patient erlitt drei Monate nach der Bestrahlung eine akute Stentthrombose, ein anderer entwickelte eine neue Stenose 3 cm proximal des gestenteten Segments zwölf Monate nach der Bestrahlungstherapie. Die Nachbeobachtungsuntersuchungen gaben bei keinem Patienten Hinweise auf Nervenschädigungen. Das die Arterie umgebende Gewede zeigte weder im CT, farbkodierten Doppler, intravasalen Ultraschall noch in der Kernspintomographie Zeichen einer Gewebsschädigung. Während oder nach der Bestrahlung traten keine Beschwerden auf. Mit Ausnahme der oben genannten Patienten, gab es im Rahmen der Langzeitbeobachtung keine Komplikationen.

Magnetic resonance imaging in the diagnosis of Fournier's gangrene.

Abstract Magnetic resonance imaging and ultrasound are the imaging modalities recommended in the early diagnosis of Fourniers gangrene. Because of the high mortality of this inflammatory disease early diagnosis is essential to initiate adequate surgical and medical treatment. In the clinical literature only a handful of cases, in which diagnosis of Fourniers gangrene is based on MRI findings, have been reported; therefore, we report another case which shows the ability of MRI especially to determine the point of origin and extension of disease.

Magnetic resonance imaging of bone marrow metastasis with fluid-fluid levels from small cell neuroendocrine carcinoma of the urinary bladder

Fluid-fluid levels have been reported as an extremely infrequent and non-specific condition in many benign and malignant bone lesions. We present the first reported MRI findings of bone marrow metastasis with fluid-fluid levels from small cell neuroendocrine carcinoma of the urinary bladder to the lumbar spine. Radiologists should be aware of the MRI appearance of these extraordinary lesions in order to provide a complete differential diagnosis and to guide clinicians in adequate treatment.

A Comparative Study of CT Fluoroscopy Combined with Fluoroscopy Versus Fluoroscopy Alone for Percutaneous Transhepatic Biliary Drainage

AbstractPurpose: We compared CT fluoroscopy (CTF) for the initial puncture of bile ducts with conventional fluoroscopic guidance in patients with malignant jaundice in whom percutaneous transhepatic biliary drainage (PTBD) was planned. Methods: Forty consecutive patients were randomized to two study groups: group A underwent PTBD under CTF and fluoroscopic guidance, group B underwent PTBD under fluoroscopic guidance alone. CTF-guided PTBD was performed using a combination of a helical CT scanner of the latest generation and a mobile C-arm; conventional PTBD was performed under fluoroscopic guidance in the angiographic unit. End points of the study were the success (a puncture that enabled safe placement of a guidewire in a suitable bile duct) and the complication rate (hemobilia, bile fistula, biliary peritonitis), the number of punctures required, the time needed for successful puncture of a suitable bile duct, and the patients radiation exposure. Results: CTF-guided puncture of peripheral bile ducts suitable for PTBD was successful at the first attempt in 16 cases, under conventional fluoroscopic guidance, in only two cases. We found a significantly different number of punctures (1.2 in group A vs 2.9 in group B), a significantly shorter time for puncture in group A (mean 39 sec), but also a significantly higher skin exposure dosage in group A (mean 49.5 mSv surface dosage). There was no significant difference regarding the total procedure time. Only one complication occurred in group B (portobiliary fistula). Conclusion: CTF-guided initial puncture of bile ducts allowed a significantly reduced number of punctures and puncture times compared with puncture under conventional fluoroscopic guidance for placement of percutaneous transhepatic biliary drainage catheters.

CTF-guided puncture of an unenhanced isodense liver lesion during continuous intravenous injection of contrast medium

CT fluoroscopy (CTF) facilitates guidance of percutaneous biopsies and other interventional procedures. We wished to demonstrate the usefulness of CTF for the puncture of an unenhanced isodense liver lésion during continuous injection of intravenous contrast medium. We performed CTF-guided puncture of a 2-cm lesion in the liver of a patient suffering from lung cancer. CTF enables puncture of liver foci even if they are unenhanced and isodense with the surrounding parenchyma.

CT fluoroscopy-guided abdominal interventions

AbstractComputed tomographic fluoroscopy (CTF) is one of the most recent developments in helical computed tomography (CT), which is increasingly being used in interventional radiology. The method combines the advantages of CT with the real-time capabilities of ultrasonography. This article reviews the current clinical applications of CTF in the monitoring of abdominopelvic interventions with reference to published clinical studies.

Successful treatment of intimal hyperplasia in renal arteries by endovascular brachytherapy.

PURPOSE The present study shows the possibility of preventing restenosis of renal arteries by endovascular brachytherapy. METHODS AND MATERIALS We present a patient suffering from rapid restenosis of both renal arteries with decreasing renal function. Percutaneous transluminal angioplasty (PTA) and stent implantation were unable to stop hypertension and to stabilize renal function. Both renal arteries and the right pole artery were treated by endovascular brachytherapy in one session. RESULTS Six months after intervention, intraarterial digital subtraction angiography (DSA) showed no evidence of recurrence, and the blood pressure remained normal without medical treatment. CONCLUSION Endovascular brachytherapy can help to prevent restenosis in renal arteries. It is possible to treat both renal arteries and one pole artery in one session without any disadvantage.

Computertomographische Beurteilung von Lokalrezidiven beim operierten und nachbestrahlten Rektumkarzinom: Regelhafte und pathologische Veränderungen nach Operation und Bestrahlung des Rektumkarzinoms in 956 CT-Untersuchungen

ZusammenfassungDas kolorektale Karzinom ist das dritthäufigste Karzinom in Deutschland. Ziel unserer radiologischen Untersuchung an Patienten mit Rektumkarzinom ist es, CT-morphologische Befunde zu beschreiben, die das Erkennen eines Rektumkarzinomrezidivs zu einem frühest möglichen Zeitpunkt ermöglichen. 232 Patienten, die an einem Rektumkarzinom erkrankt waren, wurden in einem Zeitraum von 1987–1998 nachgesorgt. In die Untersuchung eingeschlossen wurden alle Patienten, die nach Operation und Strahlentherapie mit mindestens 3 Kontroll-CT-Untersuchungen mindestens 2 Jahre nachuntersucht wurden. Alle CT-Untersuchungen wurden nach einem standardisierten Muster befundet. CT-morphologische Merkmale, die für das Vorliegen eines Lokalrezidivs sprechen, sind: eine sich vergrößernde präsakrale Raumforderung, Inhomogenität der Raumforderung, Asymmetrie, vergrößerte Lymphknoten und Infiltration benachbarter Organe. Eine unveränderte Morphologie des Präsakralraums in mehr als 3 CT-Untersuchungen spricht für Rezidivfreiheit.AbstractColorectal carcinoma is one of the most common cancer in Germany. We want to evaluate the most reliable CT features indicating local recurrence of rectal cancer as early as possible. 232 patients suffering from rectal cancer being administered to our clinic from 1987–1998 were investigated. Criteria for inclusion: patients after surgery and radiotherapy of rectal cancer with a minimum follow-up of two years and at least 3 CT examinations. All CT examinations were analyzed standardized. The main target parameters for relapse were enlargement of a presacral mass, inhomogeneous appearance, asymmetric outlines, enlarged lymph nodes and infiltration of the surrounding structures. An unchanged appearance of the presacral space in more than three CT examinations after surgery correlated with freedom of recurrence.

Functional and morphological imaging of extraadrenal myelolipoma.

Myelolipoma is a rare, hormonally inactive, benign tumor consisting of fat and hematopoietic cells. It is often encountered in the adrenal gland. Less frequently, it may occur in extraadrenal sites. Although myelolipoma is well defined by criteria of morphologic imaging, functional characteristics may be crucial to exclude malignancy.We present a case of histologically proven extraadrenal myelolipoma which was successfully diagnosed by bone marrow scintigraphy, using a monoclonal antibody directed against myeloid elements.

First experiences in percutaneous arterial chemoembolization of malignant liver lesions by means of real-time CT fluoroscopy

Computed tomography fluoroscopy (CTF) allows real-time display (continuous imaging) and has been increasingly used in interventional procedures. We wished to demonstrate the usefulness of CTF in chemoembolization of the liver. Twenty-one patients with primary or secondary malignant lesions of the liver underwent CTF-guided chemoembolization after angiographie positioning of a catheter in the hepatic artery. Embolization materials such as Lipiodol and mitomycin C were administered under continuous CT scanning. CTF led to a change of the method (correction of catheter position, application of norepinephrine) in nine of 21 cases. There were no fatal complications.