W. Schwarz

Preoperative evaluation of malignant liver tumors: comparison of unenhanced and SPIO (Resovist)-enhanced MR imaging with biphasic CTAP and intraoperative US.

Abstract. The purpose of this study was to evaluate the diagnostic efficacy of iron-oxide-enhanced MRI vs CT during arterial portography (CTAP) and intraoperative ultrasound (IOUS) in detection of liver neoplasms. Seventeen patients with malignant focal liver lesions (liver metastases, n=7), hepatocellular carcinomas (HCC, n=9), and cholangiocellular carcinoma (CCC, n=1) underwent presurgical Resovist-enhanced MRI and CTAP. Two independent observers (A and B) assessed the blinded images of unenhanced and iron-oxide-enhanced MRI vs CTAP for the presence, number, and location of the liver lesions. These results were compared lesion by lesion and segment by segment with the results of intraoperative ultrasound (n=17) serving as the reference standard. Eighty lesions were detected by intraoperative ultrasound in 17 patients. In comparison with IOUS (lesion-by-lesion analysis) the sensitivity was 86.8% for CTAP, 65% for combined unenhanced MR imaging, and 86.8% for combined Resovist-enhanced MRI as well as 86.8% for the combination of unenhanced and Resovist-enhanced MRI. Compared with the sensitivity of combined unenhanced MRI the sensitivity of CTAP as well as the sensitivity of combined Resovist-enhanced MRI was significantly higher (p<0.05). False-positive results were much higher in CTAP as compared with combined unenhanced and SPIO-enhanced MRI. Using the segment-by-segment analysis the specificity of combined unenhanced MRI with 100% (96.7–100%) as well as combined Resovist-enhanced MRI with 100% (96.7–100%) was significantly higher (p<0.05) in comparison with the specificity of CTAP with 91.1% (83.2–96.1%). The accuracy of combined unenhanced MRI was 100% (93.2–100%), combined Resovist-enhanced MRI 100% (93.6–100%) and of CTAP 85.2% (72.9–93.4%). In the detection of focal liver lesions iron-oxide-enhanced MR imaging is superior to unenhanced MRI and similar to CTAP.

Percutaneous vertebroplasty in the therapy of osteoporotic vertebral compression fractures: a critical review

Percutaneous vertebroplasty has become an efficient technique for the treatment of painful vertebral fractures. Osteoporotic vertebral compression fractures are characterized by severe back pain and immobilization causing other complications like thrombosis or pneumonia. Vertebral cement augmentation provides increased strength of the vertebral body and an obvious pain relief. Between 1989 and 2004, 30 studies and a total of 2,086 treated patients have been published in literature. A review of these studies has been performed. The number and age of the patients, number of treated vertebrae, pre- and postoperative outcome of pain and complications of the different studies were assessed and analyzed. Percutaneous vertebroplasty is an efficient technique with low complication rates and a significant reduction in pain. It rapidly improves the mobility and quality of life of patients with vertebral compression fractures. With an increasing number of treated patients, experience with this interventional technique has become excellent. But still there are no randomized controlled trials available, showing that percutaneous vertebroplasty has a significantly better outcome than other treatment options, especially after a long-term follow-up.

Traumatic injuries of the pelvis and thoracic and lumbar spine: does thin-slice multidetector-row CT increase diagnostic accuracy?

The objective is to evaluate different multidetector-row CT (MDCT) strategies for adequate classification of spinal and pelvic injuries. Seventy intubated patients after multiple trauma underwent conventional radiography (CR) and MDCT. Examinations included the pelvis (P), the lumbar spine (LS) and the thoracic spine (TS). Conventional radiographs, 3-mm (CT5) and 5-mm scans (CT3) and 3-mm and 5-mm scans combined with MPR (CT3R/CT5R) were compared to surgery, autopsy and clinical course. MDCT led to significantly better results than CR (P<0.01). Correlation coefficients were r=1.0 (CT3R), r=0.96 [TS] to r=1.0 [P/LS] (CT5R), r=0.8 [P] to r=1.0 [TS] (CT3), r=0.80 [P] to r=0.86 [TS] (CT5) and r=0.3 [TS] to r=0.69 [P] (CR). Fractures were identified by CT3R in 100% of cases, by CT5R in 95%, by CT3 in 90% [P]−100% [TS], by CT5 in 83.3% [LS]−90% [P] and by CR in 57.1% [TS]−87.2% [P]. Unstable fractures were identified in 100% by CT3R, CT5R and CT3, 85.7% [TS]−100% [P/LS] by CT5 and 57.1% [TS]−80% [P] by CR. Only overlapping thin-slice multiplanar reformation allows for an adequate classification of spinal and pelvic injuries and thus is highly emphasized in patients after severe blunt trauma.

Staging of Klatskin tumours (hilar cholangiocarcinomas): comparison of MR cholangiography, MR imaging, and endoscopic retrograde cholangiography

The aim of the study was to compare prospectively magnetic resonance cholangiography (MRC) and magnetic resonance imaging (MRI) with endoscopic retrograde cholangiography (ERC) in the diagnosis and staging of Klatskin tumours of the biliary tree (hilar cholangiocarcinomas). Forty-six patients with suspected Klatskin tumours of the biliary tract underwent MRI and heavily T2-weighted, non-breathhold, respiratory-triggered fast spin-echo MRC. Forty-two patients underwent ERC within 24xa0h; in four patients, ERC was not feasible, and percutaneous trans-hepatic cholangiography (PTC) was carried out instead. Two independent investigators evaluated imaging results for the presence of tumour, bile duct dilatation, and stenosis. Clinical and histopathological correlation revealed Klatskin tumours in 33 patients. MRI revealed a slightly hyperintense signal of infiltrated bile ducts in T2-weighted fast spin-echo sequences. The malignant lesion was regularly visualized as a hypointense area in T1-weighted gradient-echo sequences with substantial contrast enhancement along the involved bile duct walls. MRC revealed the location and extension of the tumour in 31 of 33 cases correctly (sensitivity 94%, specificity 100%, diagnostic accuracy 95%). In 27 of 31 cases, ERC enabled accurate staging and diagnosis of Klatskin tumours with a sensitivity of 87%. ERC and PTC combined yielded a sensitivity of 84% and a specificity of 97%. Tumours were grouped according to the Bismuth classification, with MRC allowing correct identification of typexa0I tumour in seven patients, typexa0II tumour in four patients, typexa0III tumour in 12 patients, and typexa0IV tumour in ten patients. MRC provided superior visualization of completely obstructed peripheral systems. MRC in combination with MRI is a reliable non-invasive diagnostic method for the pre-therapeutic staging of Klatskin tumours.

Hepatic intraarterial chemotherapy with gemcitabine in patients with unresectable cholangiocarcinomas and liver metastases of pancreatic cancer : a clinical study on maximum tolerable dose and treatment efficacy

PurposeTo define the maximum tolerated dose (MTD) of hepatic intraarterial chemotherapy with gemcitabine, administered with and without starch microspheres, in patients with inoperable intrahepatic cholangiocarcinomas and liver metastases of pancreatic carcinomas.MethodsGemcitabine was administered on days 1 and 8 with intervals of 2xa0weeks between the cycles. In group A the initial gemcitabine dose of 1,000xa0mg/m2 (without microspheres) was increased in 200-mg/m2 steps up to a maximum dose of 2,000xa0mg/m2. In group B the MTD with microspheres was assessed by giving an additional microsphere dose according to tumor extent and body weight, increasing gemcitabine starting from a dose-step below the MTD with microspheres. The MTD was evaluated via clinical and laboratory findings.ResultsTwenty-four patients were enrolled (12 males, 12 females, mean age 59.17xa0years; intrahepatic cholangiocarcinoma: nxa0=xa017, liver metastases of pancreatic carcinoma: nxa0=xa07). The MTD of gemcitabine without microspheres was reached at 1,400xa0mg/m2, and of gemcitabine with microspheres at 1,800xa0mg/m2. The comparative evaluation revealed statistically significant better data for the time to progression (pxa0<xa00.01) and survival for the group with microspheres (6.8 and 20.2xa0months) in comparison to the group without microspheres (4.2 and 13.5xa0months).ConclusionThis clinical study indicates that the intraarterial application of gemcitabine with doses higher than the recommended 1,000xa0mg/m2 is well tolerated if combined with microspheres, and yields respectable results in patients who do not respond to systemic chemotherapy.

CT-guided percutaneous vertebroplasty in the therapy of vertebral compression fractures.

The purpose of this study was to determine the efficacy and safety of CT-guided percutaneous vertebroplasty in the treatment of vertebral compression fractures. The primary objectives were pain reduction and bone-cement leakage during a long-term follow-up in patients with osteoporotic vertebral compression fractures. CT-guided percutaneous vertebroplasty was carried out in 61 patients (mean age 71.4 years; range 42–83; female ratio: 73.8%) with vertebral compression fractures. Treatment was carried out on an outpatient basis. Pain, bone-cement leakage and complications were monitored and recorded. The mean follow-up time was 19.8 months (range 3–52). Paired comparison procedures were used for the analysis of the results, which showed that all patients had a significant reduction of pain. The mean visual-analogue scale (VAS) before treatment was 8.8 points (range 6.5–9.8 points). The mean VAS score after treatment was significantly reduced to 2.6 points (range 1.5–4.1 points; p<0.01). No clinical or neurological complications were documented. Minor and asymptomatic bone-cement leakage was observed in 54% of the cases. Percutaneous vertebroplasty is an efficient and safe interventional procedure which rapidly improves the mobility and quality of life of patients with vertebral compression fractures. CT-guidance is a reasonable upgrade in the treatment procedure which reduces the amount of bone-cement leakage.

Visualization of the articular disk of the temporomandibular joint in near-real-time MRI: feasibility study

While static MRI of the TMJ is the method of choice to evaluate the articular disk (AD), dynamic MRI so far has failed to display the AD. The capability of a modified True-FISP sequence to visualize the AD in dynamic near-real-time imaging (NRTI) was evaluated. Twelve healthy subjects and 17 patients were investigated. Besides static routine imaging, sagittal NRTI of both TMJs was performed with a True-FISP sequence at 1.5xa0T with TE/TR=1.84/3.68xa0ms. Two temporal resolutions (250/500xa0ms) were tested. The quality of the visualization of the AD was rated on a four-point scale (1= very good to 4= poor visualization) by two observers in consensus. ADs of the volunteers were visualized with high quality in all stages of movement (score: 1.69). In patients with internal derangement, disk-motion was clearly depicted, including fast reposition movements. Due to degenerative changes of the AD, the quality of the depiction in patients was slightly lower (score: 2.4). According to the preliminary results of this feasibility study, the suggested NRTI True-FISP sequence is capable of visualizing the entire motion of the AD of the TMJ in normal and pathologic stages with high quality. Further studies are needed to prove the clinical usefulness of this new technique.

Role of transarterial chemoembolization for hepatocellular carcinoma before liver transplantation with special consideration of tumor necrosis.

Abstract:u2002 Several authors suggest that local ablative therapies, specifically transarterial chemoembolization (TACE), may control tumor progression of hepatocellular carcinoma (HCC) in patients who are on the waiting list for liver transplantation (orthotopic liver transplantation, OLT). There is still no evidence if TACE followed by OLT is able to prevent recurrence of tumor, to prolong survival rate of the patients on the waiting list, or to improve the survival after OLT. We report 27 patients with HCC who underwent OLT. From these patients, 15 were pre‐treated with TACE alone or in combination with percutaneous ethanol injection (PEI) or laser‐induced thermo therapy (LITT). Mean time on the waiting list was 214u2003d for treated patients and 133u2003d for untreated patients. Comparing pre‐operative imaging and histopathological staging post‐transplant, we found 13 patients with tumor progression out of which five were treated with TACE. In two of the TACE patients a decrease of lesions could be achieved. In a single patient, there was no evidence of any residual tumor. Only one patient displayed tumor progression prior to OLT despite undergoing TACE. Comparison of outcome in patients undergoing TACE or having no TACE was not statisitically significant (pu2003=u20030.5). In addition, our analysis showed that progression either in the total study population or in the TACE group alone is associated with a significant poorer outcome concerning overall survival (pu2003=u20030.02 and pu2003=u20030.02).

Nucleolysis in the herniated disk

ZusammenfassungIn Deutschland wie in anderen Industrieländern stellen der Diskusprolaps und die damit verbundene Schmerzsymptomatik ein bedeutsames und zunehmendes Gesundheitsproblem dar. Wenn die Möglichkeiten der konservativen Therapie ausgeschöpft sind, ist die Nukleolyse als minimalinvasive Alternative zur Operation zu diskutieren. Hierbei werden unter CT-Steuerung chondrolytische oder quelldruckmindernde Substanzen in den Nucleus pulposus einer protrudierten Bandscheibe injiziert. Unter den zahlreichen Substanzen, die bisher zum Einsatz kamen, erwies sich v.xa0a. die Nukleolyse mit einem Ozon-Sauerstoff-Gemisch als viel versprechend. Neben seiner hohen Wasserbindungskapazität vermag Ozon die Schmerzmediatoren vor Ort über mehrere Monate zu hemmen, wirkt antiinflammatorisch und durchblutungsfördernd. Ozon wandelt sich im Körper in reinen Sauerstoff um und besitzt eine geringe Allergenität. Bei der Nukleolyse handelt es sich um das älteste minimalinvasive Verfahren zur Therapie eines Bandscheibenvorfalls. Vergleichende Studien konnten eine Überlegenheit neuerer Therapiekonzepte, z.xa0B. der perkutanen Nukleotomie oder der Laserbehandlung, nicht bestätigen.AbstractBack pain associated with a herniated disk has become an important and increasing general health problem in Germany and other industrialized countries. After all methods of conservative treatment have been exhausted, nucleolysis may be a minimally invasive alternative to surgery. In nucleolysis, chondrolytic substances or other substances, which reduce the pressure within the disk by other means, are injected into the nucleus pulposus under CT guidance. Among various substances, which have been employed for nucleolysis, an ozone-oxygen mixture appears to be very promising. The water-binding capacity of ozone results in a reduction of pain for several months. Moreover, it has an anti-inflammatory effect and results in an increase of perfusion. Ozone is converted into pure oxygen in the body and has a low allergic potential. Recent minimally invasive therapeutic methods such as percutaneous nucleotomy or laser treatment do not result in superior results compared with nucleolysis.

Postinterventional percutaneous closure of femoral artery access sites using the Clo-Sur PAD device: initial findings.

The purpose of this study was to evaluate a percutaneous hemostatic device in patients to achieve immediate hemostasis at the vascular access site as well as early ambulation after vascular interventional procedures. In a randomized trial, a hemostatic device (Clo-Sur PAD, Medtronic AVE, Inc., Santa Rosa, CA, USA; n=60) was compared with manual compression (n=60) in patients after endoluminal intervention through an inguinal access (sheath sizes: 5–7xa0French). Device safety was evaluated by assessing complications within 24xa0h and 14xa0days. System efficacy was measured by the percentage of achieved immediate hemostasis and early ambulation. Device application was possible in 57 cases (95.0%), with 93.3% (56/60) of the patients rising 2xa0h after application. Hemostasis time was 10.15±1.96xa0min (control group: 16.20±1.79xa0min), with a pressure bandage time of 3.47±5.53xa0h (control group: 13.8±4.32xa0h). Ambulation was possible after 2.13±0.50xa0h (control group: 8.57±3.47xa0h). Complications encountered were access-site bleeding with hematoma (device: n=3; control: n=9). All complications were managed conventionally without blood transfusion or surgical intervention. The system is an easy to use device permitting early ambulation without additional pressure bandaging in the majority of patients. Preliminary data show that hemostasis does not depend on the level of anticoagulation.