High-resolution diffusion tensor imaging of human patellar cartilage: feasibility and preliminary findings.

MR diffusion tensor imaging (DTI) was used to analyze the microstructural properties of articular cartilage. Human patellar cartilage-on-bone samples were imaged at 9.4T using a diffusion-weighted SE sequence (12 gradient directions, resolution = 39 x 78 x 1500 microm(3)). Voxel-based maps of the mean diffusivity, fractional anisotropy (FA), and eigenvectors were calculated. The mean diffusivity decreased from the surface (1.45 x 10(-3) mm(2)/s) to the tide mark (0.68 x 10(-3) mm(2)/s). The FA was low (0.04-0.28) and had local maxima near the surface and in the portion of the cartilage corresponding to the radial layer. The eigenvector corresponding to the largest eigenvalue showed a distinct zonal pattern, being oriented tangentially and radially in the upper and lower portions of the cartilage, respectively. The findings correspond to current scanning electron microscopy (SEM) data on the zonal architecture of cartilage. The eigenvector maps appear to reflect the alignment of the collagenous fibers in cartilage. In view of current efforts to develop and evaluate structure-modifying therapeutic approaches in osteoarthritis (OA), DTI may offer a tool to assess the structural properties of cartilage.

[Gunshot wounds of the abdomen studied by computed tomography. The authors' personal experience in 30 cases]. / Ferite da arma da fuoco dell'addome studiate con Tomografia Computerizzata. Esperienza personale in 30 casi.

INTRODUCTION: CT plays an important role in depicting gunshot wounds in parenchymal and hollow organs in the abdomen. Relative to other techniques and to emergency laparotomy, CT permits good assessment of abdominal content, major injuries and changes in other districts, such as chest, pelvis and skull. We investigated the yield and role of CT in diagnosing abdominal gunshot wounds, with their rich and varied radiological signs and associated injuries. MATERIAL AND METHODS: We retrospectively reviewed the findings of 30 patients with abdominal gunshot wounds examined in 4 years at Loreto-Mare Hospital, Naples. All patients were men, age ranging 19-54 years (mean: 35); 6 of them were not from the European Union. Examinations were carried out from diaphragm to pubis with i.v. contrast injection and the CT angiography technique. CT was integrated with chest studies in 6 cases and with skull studies in 5. Subsequent CT follow-ups were necessary in 12 cases submitted to conservative treatment. RESULTS: Liver was the most damaged parenchyma, with hemorrhage and lacerocontusion in 7 cases and mashed in 1 case; spleen was involved in 4 cases; hemoperitoneum was found in 18 cases. Diaphragm was involved in 5 cases and pancreas in 2; gallbladder, stomach and duodenum were involved in 1 case each and jejunum-ileum and colon in 3 and 6 cases, respectively. CT showed renal injury in 3 cases and bladder injury in 2. Eight patients had vertebral gunshot damage. Pneumothorax, hemothorax and lacerocontusion were found in 7 cases; brain was injured in 4 cases and limbs in 16. DISCUSSION AND CONCLUSIONS: Tissue damage extent depends on the speed and kinetic energy the bullet carries into the abdomen. Abdominal radiography shows the bullet and its site, pneumoperitoneum from gastrointestinal perforation, crash bone injuries, vertebral trauma and subcutaneous emphysema. Instead, CT depicts early parenchymal damage and vascular injury and thus becomes a complete and necessary tool for imaging gunshot wounds. CT provides early diagnostic information which help plan emergency treatment and thus decrease mortality. As for angiography and US, we suggest they be used subsequently because in emergency they may delay the diagnosis. Moreover, vessel rupture and active intraabdominal bleeding are easily detected with spiral CT, which appears the best tool for prompt assessment of the injuries associated with gunshot wounds in other districts such as, the skull. To conclude, CT permits adequate planning of emergency surgery and helps select the cases for follow-up, intensive care and conservative treatment.

[The defecographic and clinical aspects of the solitary rectal ulcer syndrome]. / Aspetti defecografici e clinici della sindrome dell'ulcera solitaria del retto.

INTRODUCTION: Solitary rectal ulcer syndrome is a complex evacuation disorder characterized by a benign ulcerative lesion of the distal rectum; the main symptom is rectal bleeding, but mucus discharge and difficult evacuation may be associated. The clinical, endoscopic and radiologic findings of solitary rectal ulcer syndrome are evaluated in this study. The role of defecography in the diagnosis of mucosal ulceration and morphofunctional alterations such as rectal prolapse and intussusception are investigated. MATERIAL AND METHODS: In the last 5 years, 27 patients (19 women and 8 men; mean age: 38 years; range: 13-70 years) complaining of obstructed evacuation and rectal bleeding were examined with fibrosigmoidoscopy with biopsy, and defecography combined with videoproctography. Defecography was carried out sitting the patients on a defecographic chair with the pelvis in lateral projection. The images were acquired at rest, under straining, during squeezing and evacuation. RESULTS: Endoscopy and biopsy showed 21 cases of solitary ulcer (77.8%), 3 cases of multiple ulcers (11.1%), 2 cases of granular proctitis (7.4%) and 1 case of pseudopolyp of rectum (3.7%). Among anorectal dynamic alterations, only 1 case (3.7%) of large rectocele was detected at endoscopy under straining. Histo-pathological changes were compared according to Rutter and Riddel criteria; the "colitis cystica profunda" appearance was observed in 2 cases (7.4%). Defecography showed 18 cases (16.6%) of solitary ulcer, 1 case (3.7%) of multiple ulcers and 2 cases (7.4%) of granular proctitis; but it missed 3 cases (11.1%) of small solitary ulcer, 2 cases (7.4%) of small multiple ulcers, and 1 case (3.7%) of pseudopolyp. The dynamic abnormalities shown by defecography were 11 cases (40.7%) of rectal intussusception, 7 cases (25.9%) of recto-anal intussusception, 6 cases (22.2%) of external rectal prolapse and 8 cases (29.6%) of mucosal prolapse. In 16 patients (59.2%) videoprotography emphasized how the ulcer wall was the first to take part in the invagination complex. CONCLUSIONS: Double contrast barium enema represents a useful radiologic method to diagnose solitary rectal ulcer, but air insufflation and pharmacological hypotonia prevent the functional study of rectal walls. Endoscopy permits to detect mucosal ulcerations, erythema, pseudopolyps and granular proctitis; biopsy provides an accurate diagnosis. We suggest combined defecography and videoproctography as a useful tool for evaluating solitary rectal ulcer syndrome as a whole; defecography is necessary to identify associated functional abnormalities, such as rectal prolapse and intussusception, not detectable by other instrumental and radiologic investigations and considered by many authors the likely cause of the disease.