Mid-term results of Autologous Matrix-Induced Chondrogenesis for treatment of focal cartilage defects in the knee.

Articular cartilage defects heal poorly. Autologous Matrix-Induced Chondrogenesis (AMIC) is an innovative treatment for localized full-thickness cartilage defects combining the well-known microfracturing with collagen scaffold and fibrin glue. The purpose of this prospective study was to evaluate the medium-term results of this enhanced microfracture technique for the treatment of chondral lesions of the knee. Thirty-two chondral lesions in 27 patients were treated with AMIC. Within the context of clinical follow-up, these patients were evaluated for up to 5 years after the intervention. Five different scores (Meyer score, Tegner score, Lysholm score, ICRS score, Cincinnati score) as well as radiographs were used for outcome analysis. Articular resurfacing was assessed by magnetic resonance imaging (MRI). The average age of patients (11 females, 16 males; mean body mass index 26, range 20-32) was 37 years (range 16-50 years). The mean defect size of the chondral lesions was 4.2 cm(2) (range 1.3-8.8 cm(2)). All defects were classified as grade IV according to the Outerbridge classification. The follow-up period was between 24 and 62 months with a mean of 37 months. Twenty out of 23 individuals (87%) questioned were subjectively highly satisfied with the results after surgery. Significant improvement (P < 0.05) of all scores was observed as early as 12 months after AMIC, and further increased values were notable up to 24 months postoperatively. MRI analysis showed moderate to complete filling with a normal to incidentally hyperintense signal in most cases. Results did not show a clinical impact of patient's age at the time of operation, body mass index and number of previous operations (n.s.). In contrast, males showed significant higher values in the ICRS score compared to their female counterparts. AMIC is an effective and safe method of treating symptomatic full-thickness chondral defects of the knee in appropriately selected cases. However, further studies with long-term follow-up are needed to determine whether the grafted area will maintain structural and functional integrity over time.

[Update on chemoinfusion and chemoembolization treatments]. / Update Chemoperfusion und -embolisation.

In the last two decades image-guided interventional catheterizations and percutaneous ablative regional treatment procedures have revolutionized the therapy of nonresectable primary and secondary liver tumours. A distinction is made between chemoablative procedures and thermo- and radioablative procedures. The main chemoablative interventions are transarterial infusion chemotherapy (HAIC; hepatic arterial infusion chemotherapy) and transarterial (chemo-)embolization (TACE/TAE). The object of the transarterial treatment procedures is to deliver the highest possible concentration of a chemotherapy agent or combination of chemotherapy agents directly into the tumour by way of the blood vessels supplying it, while at the same time keeping the systemic effects of the drugs as small as possible. Transarterial chemoperfusion to the liver can be applied in the treatment of all primary and secondary hepatic tumours, but the main indications are hepatocellular carcinoma (HCC) and metastases from colorectal primary tumours.

[Spontaneous hemorrhage of the adrenal gland during pregnancy]. / Spontane Nebennierenblutung während der Schwangerschaft.

INTRODUCTION: Spontaneous hemorrhage is a rare cause of masses in the adrenal gland and must be differentiated from hemorrhage caused by trauma, neoplasm or metastases. CASE REPORT: A 41-year-old pregnant woman presented with nausea and right flank pain. Under suspicion of a pyelonephritis she was referred to the urological department with a normal obstetric evaluation. Ultrasound revealed an inhomogeneous mass above the right kidney, which seemed to be an abscess. An MRI scan showed an adrenal hemorrhage, but a bleeding caused by a neoplasm was excluded by a post-partum MRI control only. Upon conservative therapy the clinical condition improved and the parameters of inflammation normalized. There was no evidence of a hormone-producing adrenal tumor, an adrenal insufficiency caused by the hemorrhage, or a coagulopathy. CONCLUSION: Spontaneous hemorrhage in the adrenal gland is a rare condition in pregnancy. The diagnosis is confirmed by MRI. If conservative treatment fails, adrenalectomy will be necessary. Adrenal function should be controlled during pregnancy and post-partum. Recurrent hemorrhage and a neoplasm must be excluded by a post-partum MRI.

[Value of multislice CT for the work-up of pulmonary embolism]. / Stellenwert der Multislice-CT bei der Diagnostik der Lungenembolie.

Multislice computed tomography (MSCT) of the pulmonary arteries has overcome the limitations of single-slice CT and is accepted as the sole reference standard for imaging pulmonary embolism (PE) in many institutions. This technique provides the opportunity of efficient risk stratification to enable adequate differential therapy. With a low or intermediate pretest probability and a negative CT angiography (CTA), relevant PE can be ruled out safely. In >30% further diagnoses other than pulmonary embolism, e.g., pneumonia or aortic aneurysm, can be established on the basis of thoracic CTA. This article discusses the present role of MSCT in diagnostic imaging of PE and provides optimized acquisition protocols as well as practical aspects for secondary image reconstruction. Examples of typical imaging features of PE are shown. Diagnostic algorithms for daily emergency practice are discussed with respect to artifacts and pitfalls in image interpretation.

[Surgery of the parapharyngeal adenomas]. / Chirurgie der parapharyngealen Adenome.

Pleomorphic adenomas are the most common tumors of the parapharyngeal space (PPS) and often grow to an enormous size before becoming visible or symptomatic. CT and MRI scans are important in both diagnosis and surgical treatment. There are basically four different surgical approaches (transoral-transpalatal, transcervical-submandibular, transparotid und transmandibular) to the anterior PPS. Wide and direct exposure of the PPS is provided by a midline mandibulotomy with transection of the floor of the mouth. Owing to its morbidity this approach is reserved exclusively for extended tumors. The transcervical-submandibular route with blunt finger dissection generally offers adequate access for total tumor removal. For adenomas arising from the parotid gland a transparotid approach may be utilized. Adenomas located medially are better be resected transorally by splitting the soft palate.

[Sonography of enlarged lymph nodes: Pathogenetic categorization using contrast enhanced power Doppler sonography]. / Sonographische Diagnostik vergrösserter Lymphknoten: Pathogenetische Kategorisierung mit der kontrastverstärkten Powerdoppler-Sonographie.

BACKGROUND: The purpose of this study was to categorize enlarged superficial lymph nodes as benign or malignant using sonomorphologic features and vascularization pattern. PATIENTS AND METHODS: Enlarged superficial lymph nodes in 57 patients were assessed with B-mode and contrast-enhanced power Doppler sonography. Morphology and vascularization were evaluated. The lymph nodes were categorized as benign or malignant. Correlation was made with histology and follow-up results. RESULTS: In 55 patients, 40 lymph nodes were correctly categorized as benign and 15 lymph nodes correctly as malignant. The most reliable criteria were shape and vascularization pattern. Intact hilar vessels and branching indicated benign enlargement, destruction of the hilum with vessels running peripherally along the capsule indicated metastatic destruction. Two benign lymph nodes were considered malignant (false positive). CONCLUSION: B-mode ultrasound along with contrast-enhanced power Doppler ultrasound is an easy, cost-effective, and reliable tool for differentiation and categorization of enlarged superficial lymph nodes.

Localized nodular pigmented villonodular synovitis of the upper ankle joint--diagnosis and treatment.

This paper introduces a case of local pigmented villonodular synovits (PVNS) of the upper ankle joint in a 37-year old patient. PVNS is a neoplasia of the synovial membrane. Two different entities of PVNS are known: generalized diffuse and local nodular. They differ in their degree of destruction and growth configuration, which is crucial for prognosis and operative treatment. The most common location of the local nodular form is the knee joint, followed by the finger joints. Occurrence in the ankle joint is not common but should be considered if clinical findings are present. MRI is the method of choice for diagnosis and assessment of the bone situation. Treatment consists of radical excision of the neoplasia. Radiosynoviorthesis is recommended as a post-operative treatment to increase the probability of a total removal of persisting PVNS cells. The rate of recurrence seems to be between 8 and 46%.

[Perforated jejunal divertikula - a rare differential diagnosis of acute abdominal pain]. / Das perforierte Jejunaldivertikel - eine seltene Differentialdiagnose des akuten Abdomens.

UNLABELLED: DIAGNOSTIC FINDINGS: We report about a 83 years old female with persisting abdominal pain for 3 days. Abdominal x-ray, as well as abdominal ultrasound examination were unsuccessful. CT scan revealed a 7 cm tumor, suspicious for abscess. OPERATION: Diagnostic laparotomy showed a 6 cm inflammatory tumor with covered perforation of a jejunal diverticula at the 4th intestinal loop distal the ligament of Treitz. We performed a segmental resection. FOLLOW UP: Clinical follow-up was uneventful, the patient was without any symptoms within the first 6 months. Pre- and intraoperative pathology will be explained and discussed referring to the literature.

[Contrast-enhanced intracranial 3 D MR angiography (CE-MRA) in assessing arterial stenoses and aneurysms]. / Kontrastmittelgestützte 3D-MR-Angiographie (CE-MRA) bei intrakraniellen Stenosen und Aneurysmen.

PURPOSE: The aim of this study was to evaluate the diagnostic potential of CE-MR angiography in intracranial arterial stenoses and aneurysms. MATERIAL AND METHODS: Thirteen patients with intracranial arterial stenoses and ten patients with aneurysms, including 6 cases with GDC coil-occluded aneurysms, were examined by both 3 D TOF-MR angiography and CE-MR angiography. In cases of stenoocclusive diseases colour-coded duplex sonography and in cases of aneurysms arterial digital subtraction angiography served as reference method. RESULTS: Both TOF-MRA and CE-MRA could well depict filiform stenosis. In contrast to TOF-MRA, CE-MRA did not show any false positive stenosis or occlusion in regions of turbulent or slow blood flow. Stenoses of the medial cerebral artery could not be graded sufficiently by CE-MRA. In aneurysms the parent vessel was better shown by TOF-MRA. CE-MRA, however, more sensitively detected reperfusion in GDC coil-occluded aneurysms. CONCLUSION: Stenoses of small vessels were graded less exactly by CE-MRA than by TOF-MRA due to lower spatial resolution. CE-MRA, however, seems to be superior in regions of turbulent or slow blood flow. CE-MRA also offers advantages in follow-up examinations of coil-occluded aneurysms.

Extra- and intracellular accumulation of ultrasmall superparamagnetic iron oxides (USPIO) in experimentally induced abscesses of the peripheral soft tissues and their effects on magnetic resonance imaging.

UNLABELLED: The effects of ultrasmall superparamagnetic iron oxide (USPIO) particles on magnetic resonance imaging (MRI) were studied in an animal abscess model and the findings compared with microscopic sections of the abscesses. Staphylogenic abscesses of the right hind leg were induced in six Sprague-Dawley rats. The USPIO particles consisted of polyethylene-glycol-coated Fe3O4 with a mean size of 26 nm and were injected intravenously (i.v.), with three animals receiving a dose of 50 micromol/kg and three animals a dose of 150 micromol/kg. Before and immediately after i.v. administration of the particles, MR data were acquired with fast gradient-echo technique FLASH sequences applied over a period of 60 min. The Fe3O4-induced signal changes were registered in regions of interest (ROIs) placed over the margin and center of the abscess, over the perifocal granulation tissue and over corresponding sites of the contralateral healthy muscle. Microscopic sections were prepared using the conventional paraffin technique and, in part, a kryohistologic method before staining of the specimen with hematoxylin and Berlin-blue reaction. In addition to the mostly perfusion dependent loss of signal intensity within 8 s after injection, a signal reduction, which could be rather pronounced, was observed in the abscess margin and perifocal granulation tissue, with the underlying mechanism mainly attributed to extravasation and predominantly extracellular deposition of Fe3O4. CONCLUSION: The USPIO particles used in this study lead to a prolonged demarcation of abscesses in the peripheral soft tissues due to particle extravasation and accumulation in the periphery of the abscesses. Besides the known accumulation of already characterized USPIO in the RES of liver, spleen and lymph nodes the study could demonstrate ultrasmall iron oxide deposition (BY 818) in abscesses of the peripheral soft tissue.

Mechanisms of accumulation of small particles of iron oxide in experimentally induced osteosarcomas of rats: a correlation of magnetic resonance imaging and histology. Preliminary results.

RATIONALE AND OBJECTIVES: This study was conducted to investigate the distribution and kinetics of small particles of iron oxide in osteosarcoma-like tumors. METHODS: Magnetic resonance (MR) imaging was performed in eight athymic nude rats with an experimentally induced osteosarcoma of the right hind leg immediately after intravenous injection of a superparamagnetic iron oxide preparation. Five animals received 150 mumol iron oxide/ kg and three received 50 mumol iron oxide/kg. The iron oxide preparation consisted of polythylenglycol-coated particles with a core diameter of 6 to 8 nm. The MR images were correlated with histologic slices of the tumors. RESULTS: The tumors accumulated iron oxide rapidly. A marked decrease in signal intensity, preferentially along the periphery of the tumor, was followed by a partial return of the signal intensity within the first minute. The maximum signal decrement throughout the entire tumor exceeded 41% and 21% with one dose each of 150 mumol iron/kg and 50 mumol iron/kg, respectively. The rate of return depended on the injected dose and tumor area, with the signal intensity approaching the initial value before the injection of iron oxide after 45 minutes. Histologic correlation only showed deposition of contrast medium in the proliferative areas of the tumors, mainly confined to the tumor margin. In addition to a predominantly extracellular deposition, intracellular storage could be detected. CONCLUSIONS: The findings help to advance the understanding of the distribution and kinetics of intravenous-injected small particles of iron oxide in osteosarcoma-like tumors. A first-pass accumulation of iron oxide could be documented by MR imaging in the periphery of osteosarcomas. Due to sieving of iron oxide particles by liver, spleen, and bone marrow, the signal intensity at 45 minutes after the injection of iron oxide returned to 89% (150 mumol iron oxide/kg) and 95% (50 mumol iron oxide/kg) of the preinjection intensity.

[A comparison between GE and SE sequences in MRT after the i.v. application of superparamagnetic iron particles in the assessment of experimentally induced soft-tissue osteosarcomas]. / Vergleich zwischen GE- und SE-Sequenzen in der MRT nach i.v. Applikation von superparamagnetischen Eisenpartikeln bei der Beurteilung von experimentell induzierten Osteosarkomen der Weichteile.

PURPOSE: An MRI study on experimentally induced osteosarcomas of the peripheral soft-tissues in nude rats was conducted, comparing SE and GE sequences after i.v. application of superparamagnetic iron oxides with regard to contrast and image quality. MATERIAL AND METHODS: 40 nude rats with an osteosarcoma in the right hind leg and 7 tumour-free animals were measured without, one and 48 hours after i.v.-injection of the contrast medium. 4 SE and 3 GE sequences with different parameters and slice orientation were applied. The contrast medium consisted of Fe3O4 particles with a core diameter of 6-8 nm and a coating material of polyethylene glycol (PEG). The laboratory animals were divided into 5 groups of 7-12 animals each. The rats of the first 4 groups were given a contrast-medium dosage of 100, 150, 200 and 250 mumol Fe/kg body weight, respectively. The animals of the fifth group were tumour-free and served as controls. RESULTS: The minimum dosage for detection of Fe3O4-containing PEG magnetites, one hour after application, was established at 100-150 mumol Fe/kg body weight. The higher the dosage of the contrast medium, the more signal alterations could be measured. The GE sequences were more sensitive than SE sequences. One GE sequence with the parameters TR 90 ms, TE 13 ms, FL 8 degrees turned out to be highly sensitive. CONCLUSION: Superparamagnetic iron oxides induce signal alterations in tumours of the peripheral soft tissue. GE sequences proved to be more sensitive than SE sequences.