[Dual energy CT--a new perspective in the diagnosis of gout]. / Dual Energy CT--eine neue Perspektive in der Gicht-Diagnostik.

PURPOSE: To describe the first experience with dual energy CT (DECT) for the diagnosis of gout and to evaluate its potential for the clinical routine. MATERIALS AND METHODS: DECT examinations acquired with a dual source CT of 71 regions from 41 patients were evaluated with respect to image quality, amount of urate deposits and their location. The amount of urate deposits was described using a 4-stage scale: none (1), minimal punctual (up to 2 mm) (2), at least moderate (bigger than 2 mm) (3), soft tissue or osseus tophi (4). The DECT results were compared with the findings of the diagnostic tools currently in use. RESULTS: The DECTs of peripheral regions showed excellent image quality, while the image quality was poor in the regions of the trunk. Patients (n) and regions (r) with a score of 3 (n = 23, r = 44), 4 (n = 5, r = 8) and 1 (n = 2, r = 2) showed a highly significant correlation (p < 0.01) with the currently available diagnostic tools. In patients or regions with a score of 2 (n = 7, r = 11), the urate deposits were asymptomatic, the serum urate levels were partly elevated (43 %) and partly normal (57 %). The symptoms were ultimately able to be associated with a differential diagnosis. The urate deposits were found in tendons (57), articular synovia (25), cartilage (17), soft tissue tophi (8), osseus tophi (5), cruciate ligaments (7) and menisci (7). CONCLUSION: DECT allows specific and quantitative visualization of urate deposits in peripheral regions. Taking into account the amount of urate deposits shown in DECT, the diagnosis of gout can be stated reliably. Based on our experience and results, DECT greatly benefits the routine diagnosis of gout in peripheral regions.

Bone tunnel remodeling at the site of biodegradable interference screws used for anterior cruciate ligament reconstruction: 5-year follow-up.

PURPOSE: The purpose of this prospective study was to review, using expanded clinical-assessment tools, the long-term results of the local effects of a bioabsorbable interference screw (copolymer 85/15 D,L lactide/glycolide) in anterior cruciate ligament (ACL) reconstruction. TYPE OF STUDY: This prospective study was initiated in May 1993. The inclusion criteria for patient selection included rupture of the ACL in athletic patients without involvement of the collateral ligaments, arthroscopic ACL reconstruction using middle third of the ligamentum patella, and magnetic resonance imaging (MRI) and plain radiographic examinations of the knee joint during follow-up. MATERIALS: Between May 1993 and October 1994, 32 patients were enlisted in the study; 48 patients did not fit the inclusion criteria. There were 25 men 7 women. The average age was 29.1 years (range, 19 to 50 years). There were 21 right knees and 11 left knees. The follow-up examinations were performed by an independent examiner. There were 28 patients available for follow-up at a medium of 5.2 years (range, 4.1 to 6.4 years). The evaluation included various testing systems (i.e., OAK, IKDC, Lysholm) as well as MRI and plain radiographic studies to investigate the longevity of the implant and potential adverse effects of this new bioabsorbable material. RESULTS: The clinical results were good. The OAK score (Orthopädische Arbeitsgruppe Knie) showed 93% excellent and good results, and 7% fair results. The IKDC and Lysholm scores were 92% and 96% good and excellent results, respectively. MRI showed bone remodeling and new bone formations at the site of the implant in the femoral as well as in the tibial bone tunnel at follow-up. No cystic or osteolytic changes where seen on MRI or plain radiographs. CONCLUSIONS: This study showed the correlation between histology and MRI: there was minimal surgical-site edema, minimal reaction to this material, and complete replacement by new bone formation of the previous site of this implant. At 5 years, this bioabsorbable interference screw appeared clinically safe and effective for fixation of bone blocks during ACL reconstruction and MRI showed complete absorption and replacement with new bone.

Serial magnetic resonance imaging evaluation of operative site after fixation of patellar tendon graft with bioabsorbable interference screws in anterior cruciate ligament reconstruction.

Magnetic resonance imaging (MRI) is accepted as the imaging procedure of choice for showing internal derangement of the knee. In contrast to metal implants, bioabsorbable interference screws do not produce an artifact and provide an opportunity to expand the evaluation of the postoperative anterior cruciate ligament (ACL) ligament repair. There is the potential to evaluate the implant, the graft, the adjacent tissue, and the surgically created bone tunnels. The purpose of this study was to evaluate with MRI the postoperative site of ACL patellar tendon autografts in which bioabsorbable screws were used for fixation. It was hypothesized that a time line of bone tissue changes resulting from this type of surgery could be developed based on the expanded evaluation of MRI. From January 1993 through October 1997, 270 patients underwent surgical repair of a disrupted native ACL. There were 173 men 97 women; the average age was 25.1 years, (range, 17 to 50 years). There were 155 right knees and 115 left knees. In addition to the conventional postoperative clinical assessment and plain film radiographs, opportunistic MRIs were obtained with the patient's permission. The examinations were performed at different postoperative intervals from the third postoperative day to 4 years postoperatively. A total 206 MRIs from various time intervals were available for study. The study protocol was designed to look for loss of integrity of the screws, adjacent fluid collection, tunnel widening, and tunnel healing or narrowing. The hypothesis was substantiated in this study. The use of MRI provided observations not available by other imaging methods. The absence of metal implants for fixation provided an opportunity to examine the adjacent tissue in detail and to form a time line of the tissue response in this type of surgery.

Serial magnetic resonance imaging evaluation of a bioabsorbable interference screw and the adjacent bone.

The purpose of this prospective study was to review, using expanded clinical assessment tools, the initial use of a bioabsorbable interference screw (copolymer 85/15 D, L lactide/glycolide) in anterior cruciate ligament (ACL) reconstruction at the Wels Hospital, Austria. The study enlisted 32 patients of whom 28 were available for follow-up at minimum of 2.5 years. Since the implant material was new and the screw would not show on plain film radiographs, the clinical assessment was expanded beyond the usual historical and physical findings. The evaluation included opportunistic knee joint aspiration and repeat magnetic resonance imaging (MRI) studies to investigate the longevity of the implant and potential adverse effects of this new bioabsorbable material. The knee joint aspirations showed no infection. Serial MRIs showed the physical presence of the screw to remain intact for 4 months and disappear in 6 months. The MRIs showed minimal collection of edema around the bone tunnels that resolved by 12 months. There were no symptoms or adverse clinical result correlated with the MRI evidence of edema. There was temporary bone tunnel expansion. The clinical results were good. The OAK-score (Orthopädische Arbeitsgruppe Knie) showed 89.5% excellent and good results, 7% fair results and 3.5% poor results. The average score was 90.7 points (range, 63 to 100 points). The knee joint stability measured with the KT-1000 arthrometer showed 93% to have a 3-mm or less difference compared with the unoperated knee. This bioabsorbable interference screw appeared safe and effective for fixation of bone blocks during ACL reconstruction while producing no occult infection or adverse clinical response during the degradation process.

Bilateral testicular large-cell calcifying sertoli cell tumor and recurrent cardiac myxoma in a patient with Carney's complex.

Large-cell calcifying Sertoli cell tumors are exceedingly rare testicular tumors which can be distinguished from pure Sertoli cell tumors by distinctive microscopic features and multifocal and bilateral calcifications [1]. We describe the characteristic sonographic appearance of the tumor with pathologic correlation. This tumor also constitutes one of the conditions of Carney's complex [2], which includes cardiac and skin myxomas, myxoid mammary fibroadenomas, spotty skin pigmentation, primary pigmented nodular adrenocortical disease, pituitary adenoma and unusual testicular tumors, especially large-cell calcifying Sertoli cell tumor. We report the case of a 10-year-old boy with four of the above conditions. Recognition of this complex is important as cardiac myxomas can lead to lethal complications. Because of a tendency for familial occurrence, family members should be screened carefully [3].

Ulnar collateral ligament: differentiation of displaced and nondisplaced tears with US.

PURPOSE: To determine the usefulness of ultrasound (US) in the differentiation of displaced and nondisplaced tears of the ulnar collateral ligament (UCL). MATERIALS AND METHODS: A 7.5-10-MHz linear-array transducer was used to examine 69 patients in whom a UCL tear was suspected, 43 of whom also underwent surgery. The US findings were compared with those obtained at surgery. RESULTS: Results of US corresponded to results of surgery in 37 of 43 patients. Findings were false-positive in six patients. Twenty-six patients were treated conservatively with thumb casts. These patients showed stability and free range of motion at the first metacarpophalangeal joint at clinical follow-up (9-13 months). CONCLUSION: Sonography is useful for evaluating nondisplaced and retracted tears of the UCL and determining the need for surgery.

[Skier's thumb. Sonographic clarification of retracted ruptures]. / Der Skidaumen. Sonographische Abklärung retrahierter Rupturen.

Rupture of the ulnar collateral ligament (LCU) is the result of traumatic abduction of the metacarpophalangeal joint of the thumb ("skier's thumb"). If the ligament becomes retracted superficially to the adductor aponeurosis, surgical treatment is advocated, non-displaced tears can be treated by immobilization. Differentiation between displaced and non-displaced tears by radiography is not possible. We examined 45 patients to assess whether sonography was of help in this respect. The retracted LCU appeared as a hypoechogenic, mostly round structure medial to the metacarpal head. Using this criterion, 86% of retracted ruptures could be diagnosed correctly. Although intact LCU and nondisplaced tear cannot be differentiated consistently by sonography, high sensitivity in diagnosis of retracted ruptures seems promising, as it enables specific planning of therapeutic decisions.

Clinical in vitro endothelialization of femoropopliteal bypass grafts: an actuarial follow-up over three years.

PURPOSE: The creation of an endothelial coverage on prosthetic vascular surfaces may improve the performance of synthetic small diameter vascular grafts. In vitro lining with cultured autologous endothelial cells offers a confluent endothelium at the time of implantation. METHODS: Between June 1989 and December 1991, 49 patients who had no saphenous vein available entered the study. Indication for operation was disabling claudication in 37 patients and critical ischemia in 12 patients. With a random 1:2 assignment, 33 patients were admitted to the endothelialized group and 16 control patients received an untreated polytetrafluoroethylene prosthesis. Cultured autologous endothelial cells from the external jugular vein were confluently lined onto polytetrafluoroethylene grafts precoated with fibrinolytically inhibited fibrin glue. The follow-up was based on angiography, platelet labeling studies with indium 111-labeled oxine, assessment of the ankle-brachial index, and duplex sonography. RESULTS: First-passage mass cultures of 16 million endothelial cells-required for the confluent lining of a 70 cm long 6 mm graft-were reached 25.1 +/- 11.2 days after vein excision. Growth failure occurred in 27.3%. After 32 months, the actuarial patency was 84.7% for endothelialized grafts and 55.4% for control grafts (p < 0.041 by Breslow test; p < 0.068 by Mantel-Cox test). The ankle-brachial index was continually diverging, reaching significantly lower values in the control group at 24 months (0.98 +/- 0.14 in the endothelialized group versus 0.70 +/- 0.12 in the control; p < 0.0023). The uptake of indium 111-labeled platelets--measured at 9 days, 3 months, 6 months, and 12 months--was significantly lower in the endothelialized group during the entire observation period.