[MRI based volumetric assessment of knee cartilage after ACL-reconstruction, correlated with qualitative morphologic changes in the joint and with clinical outcome. Is there evidence for early posttraumatic degeneration?]. / MRT-basierte Knorpelvolumetrie nach Kreuzbandersatzplastik in Korrelation mit qualitativen Gelenkveränderungen und dem klinischen Outcome. Gibt es Hinweise auf frühzeitige posttraumatische degenerative Veränderungen?

PURPOSE: The purpose of this study was to analyze potential quantitative and qualitative changes of the knee cartilage and joint indicative of early posttraumatic OA 4 years after ACL-reconstruction and to correlate the MRI-findings with the clinical outcome (CO). MATERIALS AND METHODS: 1.5 T MRI-scans were performed on 9 patients post-op and 4 years later. Using a high-resolution T 1-w-fs-FLASH-3D-sequence cartilage volume (cVol) and thickness (mTh) were quantified. Using standard PD-w fs and T 1-w sequences qualitative changes of the joint structures were analyzed based on the WORMS-score. CO was rated by an orthopaedic surgeon using Lysholm-score, OAK-score, Tegner-activity-score (TAS), and Arthrometer KT-1000 testing. RESULTS: Mean changes of cVol were -1.8 % (range: -5.9 %; + 0.7 %) and of mTh -0.8 % (range: -3.0 %; + 1.1 %). No significant change (95 %-CI) could be identified for any compartment. Three patients developed new peripatellar ostheophytes, acute trauma related changes mostly decreased. Mean outcome of Lysholm-score and OAK-score were 90 pts and 86 pts, mean TAS was 4.3 pts. Average maximum tibial translation reached 5.2 mm comparing to 6.7 mm on the healthy contralateral side. CONCLUSION: Despite a tendency towards decreased cVol and mTh 4 years after ACL-reconstruction qMRI revealed no significant cartilage loss. Newly developing osteophytes did not match with the observed good CO. This small pilot study motivates future quantitative and qualitative-structural MRI-based assessment of articular cartilage and other joint structures in order to improve diagnostic tools for the detection of early OA.

[Diagnostic imaging of cartilage replacement therapy]. / Bildgebende Diagnostik von Knorpelersatztherapien.

Over the past decade a number of surgical interventions for durable cartilage repair have been developed. For the long-term follow-up of this procedures clinical scores and the morphological and biochemical evaluation of biopsies taken during arthroscopy are used.Magnetic resonance imaging is a useful noninvasive tool for the evaluation of the morphologic status of the cartilage repair tissue throughout the postoperative period. The MR imaging appearance of the most important cartilage transplantation techniques, such as autologous osteochondral transplantation, autologous chondrocyte implantation and matrix-based autologous chondrocyte implantation are described and possible complications of each technique are mentioned. The importance of new MR techniques such as high-resolution morphologic imaging and possible visualization of biochemical information of cartilage repair tissue is discussed.

Spiral CT and radiation dose.

Recent studies in the USA and Europe state that computed tomography (CT) scans compromise only 3-5% of all radiological exams, but they contribute 35-45% of total radiation dose to the patient population. These studies lead to concern by several public authorities. Basis of CT-dose measurements is the computed tomography dose index (CTDI), which was established 1981. Nowadays there are several modifications of the CTDI values, which may lead to confusion. It is suggested to use the standardized CTDI-100 w. value together with the dose length product in all CT-examinations. These values should be printed on all CT-images and allows an evaluation of the individualized patient dose. Nowadays, radiologist's aim must be to work at the lowest maximal diagnostic acceptable signal to noise ratio. To decrease radiation dose radiologist should use low kV and mA, but high pitches. Newly developed CT-dose-reduction soft-wares and filters should be installed in all CT-machines. We should critically compare the average dose used for a specific examination with the reference dose used in this country and/or Europe. Greater differences should caution the radiologist. Finally, we as radiologists must check very carefully all indications and recommend alternative imaging methods. But we have also to teach our customers-patients and medical doctors who are non-radiologists-that a 'good' image is not that which show all possible information, but that which visualize 'only' the diagnostic necessary information.

Microsurgical anterior cervical foraminotomy (uncoforaminotomy) for unilateral radiculopathy: clinical results of a new technique.

BACKGROUND: The authors report the clinical application of a new microsurgical technique. The cervical anterior foraminotomy (uncoforaminotomy), which is used for the surgical treatment of unilateral cervical radiculopathy secondary to posterolateral disc herniations or spondylotic foraminal stenoses. METHOD: Between June 2000 and May 2001, 34 patients (16 men and 18 women with a mean age of 43.8 years, range 29 to 80 years) underwent anterior cervical foraminotomy (uncoforaminotomy) for the treatment of cervical radiculopathy at one or two adjacent levels in the Neurosurgical Department of the University of Vienna. This surgical technique was devised to accomplish direct anterior decompression of the affected nerve root by removing an offending posterolateral sponylotic spur or disc fragment. The nerve root is decompressed from its origin in the spinal cord to the point were it passes behind the vertebral artery laterally. The intervertebral disc of the affected level is maintained in its form and function. Thus, the functioning motion segment is preserved and fusion related sequelae, including graft related complications, graft site complications and the adjacent level disease, are avoided. Prior to its clinical application, anatomical features of the anterior cervical spine were reviewed, and an anatomical morphometric analysis and work-up of the technique was performed in 4 cervical specimens. FINDINGS: The follow-up period varied from two to 17 months with a mean of 8.2 months. The large majority (97%) of patients were pleased with the results of their operation. The relief of neck pain and redicular pain in the affected dermatome was immediate in all patients. Motor-weakness and sensory deficit improved dramatically immediately postoperatively, and improved to normalisation in the majority of patients within 3 to 6 months. Two of the patients sustained an incomplete transient recurrent laryngeal nerve palsy, which fully resolved within two to 4 weeks. One of the patients had a repeat herniation on the second postoperative day, but recovered completely after re-operation and continued to do well at the 6-month follow-up. No permanent surgery related morbidity or associated complications were encountered. INTERPRETATION: The results indicate that this new microsurgical technique is an attractive treatment option for adequate anterior decompression of the cervical nerve root via a minimized approach. It was associated with excellent clinical outcome and a less painful postoperative course, allowing patients an almost immediate return to unrestricted full activity.

Extraforaminal, thoracic, epidural cavernous haemangioma: case report with analysis of magnetic resonance imaging characteristics and review of the literature.

BACKGROUND: A case of a solitary, thoracic, extradural, extraforaminal cavernous haemangioma causing a chronic neuralgia syndrome is presented. In the spectrum of spinal axis cavernous malformations, extradural lesions are exceedingly rare. A purely extraforaminal, paraspinal cavernous haemangioma has never been previously reported. METHOD: A 56-year-old woman suffered from a chronic neuralgia syndrome at the right D3 dermatome. Conservative treatment was ineffective. MRI revealed an extraforaminal mass at T3-4 which homogeneously enhanced after Gadolinium administration mimicking a schwannoma. The lesion was completely removed via an extraforaminal approach. FINDINGS: Histopathological investigation revealed a cavernous haemangioma. The patient recovered completely within 4 weeks after surgery. INTERPRETATION: Cavernous haemangiomas are developmental vascular hamartomas representing a single entity regardless of their location. As purely epidural lesions are rare, their clinical and radiological presentation could be confusing if located foraminally or extraforaminally. Thus, their signal characteristics providing valuable information will facilitate diagnosis and treatment.

[Radiological diagnosis of adult respiratory distress syndrome (ARDS)]. / Bildgebung bei Adult Respiratory Distress Syndrome (ARDS).

The bedside chest radiograph represents the imaging modality of choice for diagnosis and monitoring of adult respiratory distress syndrome (ARDS). Imaging findings are strongly influenced by means of mechanical ventilation therapy. The chest radiograph is relatively insensitive and not specific for the diagnosis of complications such as pneumonia or interstitial emphysema. Computed tomography (CT) is suitable for quantitative assessment of lung compartments with respect to the degree of aeration and to tissue density values. With CT, the understanding of the underlying pathophysiology and the effects of ventilation therapy (PEEP) could be improved. The role of CT in the clinical routine is still limited due to the high risk to transport patients with ARDS.