Head to head comparison of optical coherence tomography, intravascular ultrasound echogenicity and virtual histology for the detection of changes in polymeric struts over time: insights from the ABSORB trial

To analyse and to compare the changes in the various optical coherence tomography (OCT), echogenicity and intravascular ultrasound virtual histology (VH) of the everolimus-eluting bioresorbable scaffold (ABSORB) degradation parameters during the first 12 months after ABSORB implantation. In the ABSORB study, changes in the appearance of the ABSORB scaffold were monitored over time using various intracoronary imaging modalities. The scaffold struts exhibited a progressive change in their black core area by OCT, in their ultrasound derived grey level intensity quantified by echogenicity, and in their backscattering ultrasound signal, identified as "pseudo dense-calcium" (DC) by VH.

Clinical study of mucosa-associated lymphoid tissue lymphomas of the head and neck

Background: Limited information is available on mucosa-associated lymphoid tissue lymphomas arising in the head and neck. Method: A retrospective analysis was conducted of 20 patients who were histologically diagnosed with mucosa-associated lymphoid tissue lymphoma and treated at our institution between January 1990 and December 2009. Results: Treatment consisted of surgical resection alone in two patients (10 per cent), surgical resection with consecutive radiotherapy in one (5 per cent), and radiotherapy alone in eight (40 per cent). Three patients (15 per cent) were treated with systemic chemotherapy, and three (15 per cent) received chemoradiotherapy. Three patients (15 per cent) were informed of the diagnosis but not treated for their condition. Conclusion: All of the 20 patients were still alive after a mean follow-up period of 50.8 months. Local treatment for mucosa-associated lymphoid tissue lymphoma of the head and neck should be the first choice in early-stage disease. However, prolonged follow up is important to determine these patients' long-term response to treatment.

Diffusion-weighted MR imaging in the head and neck

Extracranial applications of diffusion-weighted (DW) magnetic resonance (MR) imaging are gaining increasing importance, including in head and neck radiology. The main indications for performing DW imaging in this relatively small but challenging region of the body are tissue characterization, nodal staging, therapy monitoring, and early detection of treatment failure by differentiating recurrence from posttherapeutic changes. Lower apparent diffusion coefficients (ADCs) have been reported in the head and neck region of adults and children for most malignant lesions, as compared with ADCs of benign lesions. For nodal staging, DW imaging has shown promise in helping detect lymph node metastases, even in small (subcentimeter) nodes with lower ADCs, as compared with normal or reactive nodes. Follow-up of early response to treatment is reflected in an ADC increase in the primary tumor and nodal metastases; whereas nonresponding lesions tend to reveal only a slight increase or even a decrease in ADC during follow-up. Optimization and standardization of DW imaging technical parameters, comparison of DW images with morphologic images, and increasing experience, however, are prerequisites for successful application of this challenging technique in the evaluation of various head and neck pathologic conditions.

[Case report: an exceptional case of a monozygotic thoracopagus parasiticus in a German Holstein calf]

A black and white German Holstein calf displayed a complex double malformation in shape of a thoracopagus parasiticus. By means of a molecular genetic investigation the genesis of the malformation from one zygote could be demonstrated. Both vertebral columns showed a pronounced lordosis, with the vertebral column of one animal ending in a rudimentary head. Close to this rudiment two derivates of branchial arches were found. The two thoracic cavities merged into one "thorax". In the shared thoracic cavity one heart was found. In its right atrium, a cherry-sized structure was found in which heart- and vascular smooth muscles were demonstrated histologically. The aorta split shortly after its origin to provide both animals with one aorta each. The larger pair of lungs was connected with a trachea leading to the head while the smaller pair of lungs originated from a trachea deriving from the rudimentary head. The diaphragm jejunum and split afterwards. The pedigree of the affected animal showed neither inbreeding nor any other affected animal.

Nitric oxide and metalloproteinases in canine articular ligaments: a comparison between the cranial cruciate, the medial genual collateral and the femoral head ligament

Osteoarthritis due to cranial cruciate ligament (CCL) rupture or hip dysplasia is one of the most important causes of chronic lameness in dogs. This study aimed at comparing nitric oxide (NO) production by the CCL with that of the femoral head ligament (FHL) and the medial collateral ligament (MCL), and investigating the pathway of NO production and the concomitant metalloproteinase (MMP) activity in the presence or absence of an inflammatory stimulus. Ligaments of normal dogs were subjected to different stimuli, and NO and MMP activity from explant culture supernatants were compared. The results showed that in explant cultures of the canine CCL more NO was produced than in those of the other two ligaments. A higher level of NO was produced when CCLs were exposed to the inducible nitric oxide synthase (iNOS)-inducing cocktail TNF/IL-1/LPS, and NO synthesis could be inhibited by both l-NMMA, a general nitric oxide synthase (NOS) inhibitor and l-NIL, a specific iNOS inhibitor. However, a correlation between NO synthesis and iNOS expression levels as determined by immunohistochemistry was not observed. In contrast to CCL, no evidence for iNOS-dependent NO synthesis was observed for MCL and FHL. The CCL produced less MMP than MCL and FHL, and no correlation between MMP and NO could be demonstrated. MMP activity in the CCL increased significantly after 48 h of incubation with the inflammatory stimulus. The results suggest that in canine osteoarthritis NO synthesized by canine CCL plays a more important role in the pathogenesis of osteoarthritis of the stifle than that synthesized by FHL and MCL.

Stent grafting of acute hepatic artery bleeding following pancreatic head resection

The purpose of this study was to report the potential of hepatic artery stent grafting in cases of acute hemorrhage of the gastroduodenal artery stump following pancreatic head resection. Five consecutive male patients were treated because of acute, life-threatening massive bleeding. Instead of re-operation, emergency angiography, with the potential of endovascular treatment, was performed. Because of bleeding from the hepatic artery, a stent graft (with the over-the-wire or monorail technique) was implanted to control the hemmorhage by preserving patency of the artery. The outcome was evaluated. In all cases, the hepatic artery stent grafting was successfully performed, and the bleeding was immediately stopped. Clinically, immediately after the procedure, there was an obvious improvement in the general patient condition. There were no immediate procedure-related complications. Completion angiography (n=5) demonstrated control of the hemorrhage and patency of the hepatic artery and the stent graft. Although all patients recovered hemodynamically, three individuals died 2 to 10 days after the procedure. The remaining two patients survived, without the need for re-operation. Transluminal stent graft placement in the hepatic artery is a safe and technically feasible solution to control life-threatening bleeding of the gastroduodenal artery stump.

Trochanteric flip osteotomy for cranial extension and muscle protection in acetabular fracture fixation using a Kocher-Langenbeck approach

OBJECTIVE: To describe the advantages and surgical technique of a trochanteric flip osteotomy in combination with a Kocher-Langenbeck approach for the treatment of selected acetabular fractures. DESIGN: Consecutive series, teaching hospital. METHODS: Through mobilization of the vastus lateralis muscle, a slice of the greater trochanter with the attached gluteus medius muscle can be flipped anteriorly. The gluteus minimus muscle can then be easily mobilized, giving free access to the posterosuperior and superior acetabular wall area. Damage to the abductor muscles by vigorous retraction can be avoided, potentially resulting in less ectopic ossification. Ten consecutive cases of acetabular fractures treated with this approach are reported. In eight cases, an anatomic reduction was achieved; in the remaining two cases with severe comminution, the reduction was within one to three millimeters. The trochanteric fragment was fixed with two 3.5-millimeter cortical screws. RESULTS: All osteotomies healed in anatomic position within six to eight weeks postoperatively. Abductor strength was symmetric in eight patients and mildly reduced in two patients. Heterotopic ossification was limited to Brooker classes 1 and 2 without functional impairment at an average follow-up of twenty months. No femoral head necrosis was observed. CONCLUSION: This technique allows better visualization, more accurate reduction, and easier fixation of cranial acetabular fragments. Cranial migration of the greater trochanter after fixation with two screws is unlikely to occur because of the distal pull of the vastus lateralis muscle, balancing the cranial pull of the gluteus medius muscle.

Comparison of six radiographic projections to assess femoral head/neck asphericity

Early radiographic detection of femoroacetabular impingement might prevent initiation and progression of osteoarthritis. The structural abnormality in femoral-induced femoroacetabular impingement (cam type) is frequently asphericity at the anterosuperior head/neck contour. To determine which of six radiographic projections (anteroposterior, Dunn, Dunn/45 degrees flexion, cross-table/15 degrees internal rotation, cross-table/neutral rotation, and cross-table/15 degrees external rotation) best identifies femoral head/neck asphericity, we studied 21 desiccated femurs; 11 with an aspherical femoral head/neck contour and 10 with a spherical femoral head/neck contour. To radiographically quantify femoral head asphericity, we measured the angle where the femoral head/neck leaves sphericity (angle alpha). The aspherical femoral head/neck contours had a greater maximum angle alpha (70 degrees ) compared with the spherical head/neck contours (50 degrees ). The angle alpha varied depending on the radiographic projection: it was greatest in the Dunn view with 45 degrees hip flexion (71 degrees +/- 10 degrees ) and least in the cross-table view in 15 degrees external rotation (51 degrees +/- 7 degrees ). Diagnosis of a pathologic femoral head/neck contour depends on the radiologic projection. The Dunn view in 45 degrees or 90 degrees flexion or a cross-table projection in internal rotation best show femoral head/neck asphericity, whereas anteroposterior or externally rotated cross-table views are likely to miss asphericity. Level of Evidence: Prognostic study, level II-1 (retrospective study).

Effects of glenoid component version on humeral head displacement and joint reaction forces: an experimental study

The purpose of this study was to determine whether changes in glenoid version are associated with humeral head displacement and changes in the joint reaction forces, as these might contribute to instability or loosening in total shoulder replacement. A total shoulder prosthesis was implanted in neutral version in 6 cadaveric shoulders. Glenoid version was then changed in steps of 4 degrees toward more anteversion and retroversion. An increase in anteversion resulted in anterior translation of the humeral head and in eccentric loading of the anterior part of the glenoid. Retroversion was associated with posterior displacement and posterior loading of the glenoid. A change in rotation of the humeral component did not compensate for altered version of the glenoid component. These results suggest that both instability and glenoid component loosening may be related to the version of the glenoid component. Therefore, assessment of loosening and instability justifies precise assessment of glenoid component version.

Prospective navigator-echo-based real-time triggering of fetal head movement for the reduction of artifacts

The purpose of this study was to evaluate the neuroimaging quality and accuracy of prospective real-time navigator-echo acquisition correction versus untriggered intrauterine magnetic resonance imaging (MRI) techniques. Twenty women in whom fetal motion artifacts compromised the neuroimaging quality of fetal MRI taken during the 28.7 +/- 4 week of pregnancy below diagnostic levels were additionally investigated using a navigator-triggered half-Fourier acquired single-shot turbo-spin echo (HASTE) sequence. Imaging quality was evaluated by two blinded readers applying a rating scale from 1 (not diagnostic) to 5 (excellent). Diagnostic criteria included depiction of the germinal matrix, grey and white matter, CSF, brain stem and cerebellum. Signal-difference-to-noise ratios (SDNRs) in the white matter and germinal zone were quantitatively evaluated. Imaging quality improved in 18/20 patients using the navigator echo technique (2.4 +/- 0.58 vs. 3.65 +/- 0.73 SD, p < 0.01 for all evaluation criteria). In 2/20 patients fetal movement severely impaired image quality in conventional and navigated HASTE. Navigator-echo imaging revealed additional structural brain abnormalities and confirmed diagnosis in 8/20 patients. The accuracy improved from 50% to 90%. Average SDNR increased from 0.7 +/- 7.27 to 19.83 +/- 15.71 (p < 0.01). Navigator-echo-based real-time triggering of fetal head movement is a reliable technique that can deliver diagnostic fetal MR image quality despite vigorous fetal movement.

Basement membrane remodeling in skeletal muscles of patients with limb ischemia involves regulation of matrix metalloproteinases and tissue inhibitor of matrix metalloproteinases

BACKGROUND/AIM: Because the pericapillary basement membrane in skeletal muscles of patients with chronic critical limb ischemia (CLI) is thickened, we determined the expression patterns of genes involved in collagen metabolism, using samples from 9 CLI patients, 4 patients with acute limb ischemia and 4 healthy controls. METHODS: Gene array analysis, quantitative RT-PCR and semiquantitative grading of immunohistochemical reactivity were performed to determine mRNA/cDNA and protein concentrations. RESULTS: In CLI patients compared to controls, cDNA levels of matrix metalloproteinase (MMP)-9 and MMP-19 were higher, collagen type IV chains A1 and A2, tissue inhibitor of matrix metalloproteinase (TIMP)-1 and TIMP-2 were similar and MMP-2 were lower. On the protein level, MMP-2, MMP-9, MMP-19 and TIMP-1 were more abundantly expressed. In skeletal muscles from patients with acute limb ischemia, cDNA and protein levels of MMP-9, MMP-19, collagen type IV chains, TIMP-1 and TIMP-2 were high. MMP-2 was elevated at the protein but decreased on the cDNA level. CONCLUSION: Expression of basement membrane components in skeletal muscles of CLI and acute limb ischemia patients is altered, possibly contributing to the pathogenesis of peripheral arterial disease.