Thoracoscopy in the horse: diagnostic and therapeutic indications in 28 cases.

Thirty-two thoracoscopies were performed in 28 horses. Sixteen horses were affected with pleuropneumonia whereas 12 were affected with various other thoracic conditions. The indications for thoracoscopy was diagnostic in 19 cases, therapeutic in 11 cases and both diagnostic and therapeutic in 2 cases. Twenty-six thoracoscopies were done standing whereas 6 were performed under general anaesthesia. The specific procedures performed during thoracoscopy were exploratory only (7), biopsy of the lung and lymph nodes (10), drain placement into pleural effusions (2) and abscesses (5), exploration prior to thoracotomy (2), transection of pleural adhesions and decortication (1) and window pericardectomy (2). Diaphragmatic hernia repair (2) and partial pneumonectomy (1) were initiated thoracoscopically but conversion to thoracotomy was necessary for completion. Standing thoracoscopy was well tolerated in most horses. Transient exacerbation of pulmonary compromise evidenced by tachypnoea was readily alleviated by reinflation of the lung. Standing thoracoscopy provided good visualisation of the dorsal and lateral structures of the thorax. The ventral thoracic structures and the cranial ventral diaphragmatic surfaces of the lungs were best visualised in dorsal or lateral recumbency under general anaesthesia. Thoracoscopy is a safe and useful diagnostic and therapeutic tool in horses with thoracic diseases.

Laparoscopic intra-abdominal ligation and removal of cryptorchid testes in horses.

Laparoscopic intra-abdominal ligation and removal of cryptorchid testes in horses was evaluated retrospectively in 50 horses that underwent the procedure between 1991 and 1996. Sixty-one cryptorchid testes were removed by one of the following methods; the use of 1) an endoscoping stapling and transection device, 2) an endoscopic clipping device, 3) an endoscopic ligating loop. Monopolar electrosurgery was combined with these methods to facilitate coagulation and cutting of tissue. In 8 horses, 9 testes were retained between the internal and external inguinal rings. The inguinal testes were removed by cutting the internal inguinal ring and bringing the testis back into the abdomen for removal. No attempt was made to close the internal inguinal ring. The most frequently employed and most cost effective method for laparoscopic intra-abdominal removal of cryptorchid testes in this study was the combined use of an endoscopic ligating loop and monopolar electrosurgery. One intra-operative complication (perforation of the small intestine) occurred and was dealt with successfully. One horse developed a fever attributed to upper respiratory tract infection post operatively and was treated successfully with antibiotic. Intra-abdominal ligation and transection of cryptorchid testes is an effective method for cryptorchid castration. This technique minimises the loss of insufflation, allows inspection of the cut tissue for haemorrhage and offers secure closure of the abdominal wall preventing inguinal herniation and excellent visualisation of the cryptorchid testis.

[Large granular T-cell lymphocytic leukemia disclosed by bilateral uveitis: association with celiac disease]. / Leucémie à grands lymphocytes granuleux T révélée par une uvéite bilatérale: association à une maladie coeliaque.

A 70-year-old woman presented with bilateral anterior uveitis. She was on a gluten-free diet because of a celiac disease which had been diagnosed 3 months before. An anterior chamber aspirate contained a majority of large granular lymphocytes (LGL). The investigation of a chronic neutropenia led to the diagnosis of an otherwise typical T-LGL leukemia. This seems to be the first report of a CD3+ CD4- CD8+ T-LGL leukemia causing anterior uveitis through infiltration of leukemic cells, and the second report of an intriguing association of celiac disease with T-LGL leukemia.

Use of diagnostic ultrasonography in horses with signs of acute abdominal pain.

OBJECTIVE: To evaluate the use of abdominal ultrasonography as a diagnostic tool in horses with signs of colic. DESIGN: Prospective study. ANIMALS: 226 horses with signs of acute abdominal pain were compared to 20 clinical normal horses. PROCEDURE: The following were performed in horses with signs of colic: physical examination, CBC, abdominal fluid analysis, placement of a nasogastric tube to obtain gastric reflux, abdominal palpation per rectum, and ultrasonography of the abdomen. Results of ultrasonography were compared with the surgical, necropsy, or medical findings. RESULTS: Ultrasonography of horses with primary small-intestine lesions revealed images of small intestine with a wall thickness of 0.2 to 1.8 cm and a diameter of 3.6 to 13.5 cm without evidence of motility. Horses with peritonitis did have evidence of small-intestine motility on ultrasonography with a wall thickness of 0.5 to 1.3 cm and a diameter of 2 to 5.1 cm. Horses with primary large-colon lesions or small-colon impactions had small-intestine diameters on ultrasonographic evaluation of 3 to 7.1 cm. In these horses, small-intestine motility was detected. If abnormal small intestine that lacked motility was detected by ultrasonographic evaluation, the sensitivity, specificity, and positive and negative predictive values for small-intestine stragulation obstructions were 100%. Detection of distended or edematous small intestine by abdominal palpation per rectum provided a sensitivity of 50%, specificity of 98%, positive predictive value of 89%, and negative predictive value of 89% for small-intestine strangulation obstructions. CLINICAL IMPLICATIONS: The use of abdominal ultrasonography. In horses with signs of colic is accurate for detecting small-intestine strangulation obstructions.

Laparoscopic inguinal herniorrhaphy in two stallions.

Two mature stallions that were used for breeding purposes were admitted for evaluation of inguinal hernias. In 1 horse, the hernia was reduced per rectum by gentle traction applied to the intestine. In the other horse, the hernia was reduced by placing the horse in dorsal recumbency and applying external pressure over the scrotum. Both horses were observed for recurrence of the hernia. Seven days later, an elective laparoscopic technique for inguinal herniorrhaphy was performed on each horse, using polypropylene mesh. Complications did not develop, and both horses have successfully completed 2 full breeding seasons. Laparoscopic inguinal herniorrhaphy allows preservation of the testis on the affected side and precludes many complications associated with open surgical techniques used on inguinal rings.

Small intestinal herniation through the epiploic foramen: 53 cases (1987-1993).

The incidence of epiploic entrapment of the small intestine in horses undergoing celiotomy for colic was 5%. The condition was more prevalent in older (mean 9.81 years) gelding and Thoroughbred horses. Preoperative peritoneal protein level was a good prognostic indicator as it was significantly greater in the nonsurvivor (39.4 +/- 5.10) group than in the survivor group (26.6 +/- 14.0) (P<0.05). Abdominal ultrasonography allowed earlier diagnosis and surgical intervention in nonpainful cases with inconclusive rectal findings. Surgery was completed in 46 horses and 44 horses recovered from anaesthesia. Nine horses were either subjected to euthanasia in surgery (7 horses) or died in recovery (2 horses). Repeat laparotomies were pursued in 27% (12/44) of the horses. Seven horses (16%) showed post operative adynamic ileus which was the most common post operative complication. The incidence (6%) of adhesion formation was lower than previously reported. Other post operative complications included gastric ulceration, liver disease, diarrhoea and weight loss. Short and long term survival rates were 79% (35/44) and 70% (31/44) respectively. Improved rates were attributed to earlier referral and diagnosis and prompt surgical intervention. The aggressive use of repeat celiotomy and a more effective treatment of the endotoxic horse in the perioperative period contributed to survival.

Laparoscopic cryptorchidectomy in horses.

Laparoscopic cryptorchidectomy was successfully performed in 15 standing or recumbent horses. In 3 horses, owners believed that castrations had been performed, but the horses had retained stallion-like behavior. Successful removal of undescended testes in these horses stopped this behavior. Laparoscopy offered excellent visualization of the structures of the vaginal ring and facilitated removal of the abdominally located testis. The internal and external inguinal rings were not invaded, thus the chance of serious complications that may result during open cryptorchidectomy procedures was minimized.

Morphologic and biochemical study of sternal cartilage autografts for resurfacing induced osteochondral defects in horses.

Using biodegradable pins, sternal cartilage autografts were fixed into osteochondral defects of the distal radial carpal bone in ten 2 to 3-year-old horses. The defects measured 1 cm2 at the surface and were 4 mm deep. Control osteochondral defects of contralateral carpi were not grafted. After confinement for 7 weeks, horses were walked 1 hour daily on a walker for an additional 9 weeks. Horses were euthanatized at 16 weeks. Half of the repair tissue was processed for histologic and histochemical (H&E and safranin-O fast green) examinations. The other half was used for the following biochemical analyses: type-I and type-II collagen contents, total glycosaminoglycan content, and galactosamine-to-glucosamine ratio. On histologic examination, the repair tissue in the grafted defects consisted of hyaline-like cartilage. Repair tissue in the nongrafted defects consisted of fibrocartilaginous tissue, with fibrous tissue in surface layers. On biochemical analysis, repair tissue of grafted defects was composed predominantly of type-II collagen; repair tissue of non-grafted defects was composed of type-I collagen. Total glycosaminoglycan content of repair tissue of grafted defects was similar to that of normal articular cartilage. Total glycosaminoglycan content of nongrafted defects was 62% of that of normal articular cartilage (P less than 0.05). Repair tissue of all defects was characterized by galactosamine-to-glucosamine ratio significantly (P less than 0.05) higher than that of normal articular cartilage. These results at 16 weeks after grafting indicate that sternal cartilage may potentially constitute a suitable substitute for articular cartilage in large osteochondral defects of horses.

Morphologic study of repair of induced osteochondral defects of the distal portion of the radial carpal bone in horses by use of glued periosteal autografts [corrected].

The use of periosteal autografts to resurface osteochondral defects was investigated in 10 horses (2 to 3 years old), and the repair tissue was characterized morphologically. Middle carpal joint arthrotomies were made, and osteochondral defects were induced bilaterally on the distal articular surface of each radial carpal bone. Each defect measured approximately 1 cm2 and extended 3 mm into the subchondral bone plate. Residual subchondral bone plate of control and principal defects was perforated by drilling. A sterile fibrin adhesive was made by mixing a fibrinogen component and a thrombin component. A periosteal autograft was harvested from the proximal portion of the tibia and was glued onto the recipient osseous surface, with its cambium facing the joint cavity. Control defects were glued, but not grafted. Horses were walked 1 hour daily on a walker, starting at postoperative week 7 and continuing for 9 weeks. Sixteen weeks after the grafting procedure was done, carpal radiography was performed, after which horses were euthanatized. Quality of repair tissue of control and grafted defects was evaluated and compared grossly, histologically, and histochemically. Using a reticule, the proportions of various repair tissue types filling each defect were quantitated. Seven weeks after the grafting procedure was done, bilateral arthroscopy revealed synovial adhesions and marginal pannus formation in control and grafted defects. None of the autografts was found floating unattached within the respective middle carpal joints. At 16 weeks, the gross appearance of most grafted and nongrafted defects was similar, and repair was dominated by a fibrous pannus. In 4 grafted defects, bone had formed either concentrically within the defect or eccentrically in the fibrous adhesions between the defect and the joint margin. Histologically, all grafted and nongrafted defects were repaired similarly by infiltration of a mixture of fibrous tissue, fibrocartilage, and bone. Fibrous tissue was the predominant tissue in most defects and its mean proportion was 56 and 59% in the grafted and nongrafted defects, respectively. Fibrocartilaginous tissue in the deeper layers approximated 20%, and woven bone at the base of the defect was 20% in all defects. Histochemically, difference in staining for proteoglycans was not observed between grafted and nongrafted defects. Little remaining original periosteal graft tissue was evident at the defect sites. The only distinguishing feature of grafted defects was the presence of islands of bone formation either at the defect site (n = 2 horses), or in somewhat dorsally displaced tissue that was incorporated in fibrous adhesions (n = 2 horses).(ABSTRACT TRUNCATED AT 400 WORDS)

Biochemical study of repair of induced osteochondral defects of the distal portion of the radial carpal bone in horses by use of periosteal autografts.

Periosteal autografts were used for repair of large osteochondral defects in 10 horses aged 2 to 3 years old. In each horse, osteochondral defects measuring 1.0 x 1.0 cm2 were induced bilaterally on the distal articular surface of each radial carpal bone. Control and experimental defects were drilled. Periosteum was harvested from the proximal portion of the tibia and was glued into the principal defects, using a fibrin adhesive. Control defects were glued, but were not grafted. Sixteen weeks after the grafting procedure, the quality of the repair tissue of control and grafted defects was assessed biochemically. Total collagen content and the proportion of type-II collagen were determined. Galactosamine and glucosamine contents also were determined. From these measurements, contents of chondroitin and keratan sulfate and total glycosaminoglycan, and galactosamine-to-glucosamine ratio were calculated. All biochemical variables were compared with those of normal equine articular cartilage taken from the same site in another group of clinically normal horses. Total collagen content was determined on the basis of 4-hydroxyproline content, using a colorimetric method. The proportions of collagen types I and II in the repair tissue were assessed by electrophoresis of their cyanogen bromide-cleaved peptides on sodium dodecyl sulfate slab gels. Peptide ratios were computed and compared with those of standard mixtures of type-I and type-II collagens. Galactosamine and glucosamine contents were determined by use of ion chromatography. In general, the biochemical composition of repair tissue of grafted and nongrafted defects was similar, but clearly differed from that of normal articular cartilage.(ABSTRACT TRUNCATED AT 250 WORDS)

Biochemical analysis of normal articular cartilage in horses.

Articular cartilage specimens from the distal articular surface of 32 radiocarpal bones from 24 2- to 5-year-old horses were analyzed. The total collagen content was determined on the basis of the 4-hydroxyproline content, using a colorimetric method. A method for estimating the proportions of types-I and -II collagen by measuring spectrophotometric densities of specific cyanogen bromide peptide bands from mixtures of types-I and -II collagen on sodium dodecyl sulfate-polyacrylamide gels was used. The cyanogen bromide peptides representative of each collagen types-I and -II were identified. The peptide ratios were then computed for each of several standards of type-I and -II mixtures. A standard curve was derived from the correlation between these ratios and the corresponding proportions of type-II collagen in standard mixtures. Galactosamine and glucosamine content (hexosamines) were measured by ion chromatography. The galactosamine-to-glucosamine ratio, chondroitin sulfate and keratan sulfate values, and total glycosaminoglycan content were derived from the measured hexosamine content. The total collagen content averaged 556 mg/g (55.6 mg/100 mg) of tissue (dry weight, [dw]). Type-II collagen was the major collagen type in normal articular cartilage specimens. The ratio of the area under the alpha 1 (II)CB10 peak to the area under the alpha 1 (I)CB 7,8 + alpha 1 (II)CB11 peak was a second-order polynomial function of the proportion of type-II collagen in the specimens. The mean galactosamine and glucosamine content were 20.6 mg/g and 7.9 mg/g (dw), respectively. The mean galactosamine-to-glucosamine ratio was 3.74 +/- 0.62.(ABSTRACT TRUNCATED AT 250 WORDS)

Surgical management of Rhodococcus equi metaphysitis in a foal.

A chronic Rhodococcus equi metaphysitis involving the distal growth plate of the left third metatarsal bone had induced a longstanding lameness in a young foal. Abnormal hematologic values included mild anemia, hyperfibrinogemia, mild leukocytosis, and neutrophilia. Radiography of the distal portion of MT3 revealed a radiolucent zone on the medial aspect of the growth plate, and small pieces of bone suggestive of sequestra. Treatment with erythromycin estolate and rifampin, aggressive surgical debridement, and cancellous bone grafting helped resolve the bone infection.

Neochondrogenesis in free intra-articular, periosteal, and perichondrial autografts in horses.

Periosteal autografts were obtained from the medial aspect of the proximal portion of the tibia, and perichondrial autografts were obtained from the sternum. Using arthroscopic visualization, each autograft was placed as a loose body into 1 tarsocrural joint in 6 young horses (2 to 4 years old). Horses were hand-walked daily, starting the day after surgery, for a total of 6 h/wk for 8 weeks. Eight weeks after autograft implantation, radiographs were taken of each tarsocrural joint and were interpreted with regard to mineralization in the transplanted autografts. Autografts were then surgically removed, and examined macroscopically and microscopically for viability, size, and production of chondroid tissue. All autografts appeared viable and most had evidence of growth. Longest-by-shortest axis value, cross-sectional area, and perimeter were greater in perichondrial autografts than in their periosteal counterparts in 3 horses, but the difference was not significant. Neochondrogenesis was observed in 5 of 6 periosteal grafts and in 1 of 6 perichondrial grafts. Furthermore, the amount of chondroid tissue produced in periosteal autografts was significantly (P less than 0.05) greater than that produced in the 1 perichondrial graft. The chondroid tissue produced by periosteal autografts had morphologic and matrical staining properties similar to those of hyaline cartilage.

Review of pathogenesis and treatment of degenerative joint disease.

Treatment of degenerative joint disease (osteoarthritis) is discussed in relationship to pathogenesis of five clinical entities, defined to facilitate discussion:-1) occurring in high motion joints and associated with synovitis; 2) associated with low motion joints; 3) "non-progressive" articular cartilage erosion; 4) secondary to other identified problems (intra-articular fractures, ligamentous damage, wounds, septic arthritis, osteochondrosis); and 5) chondromalacia of the patella. In addition to direct damage to articular cartilage, synovitis and capsulitis and depletion of matrical glycosaminoglycans and proteoglycans play important roles. The natural healing response in damaged articular cartilage is inadequate. The principles of treatment are divided into: 1) prevention or treatment of primary causes. These include the effects of track surface, shoeing, and the appropriate resolution of intra-articular fractures, septic arthritis and osteochondritis dissecans. 2) treatment of active soft tissue disease contributing to articular cartilage degeneration, including rest, physical therapy, synovectomy and administration of anti-inflammatory drugs, sodium hyaluronate and polysulfated glycosaminoglycans. 3) attempts at treatment of articular cartilage loss or degeneration, including articular cartilage curettage, subchondral bone drilling, osteophyte removal, articular cartilage grafting and arthrodesis.

Internal fixation of a proximal metatarsal fracture in a calf.

An open proximal metatarsal fracture was identified in a 9-month-old calf. Open reduction, internal fixation, and external coaptation were used to repair the fracture. The calf recovered without complications and was reported to be sound 6 months after surgery.

A radioprotector: cysteamine, inhibits oxygen transport in lipidic membranes.

Spin labeling techniques make possible the observation of oxygen diffusion or concentrations in phospholipid membranes. In such a system, cysteamine, depending upon the molecular cysteamine/DPPC ratio and the pH conditions, inhibits oxygen transport, and this result provides an original explanation for cellular hypoxia after cysteamine administration.

Evaluation of the repair process of cartilage defects of the equine third carpal bone with and without subchondral bone perforation.

To determine the effect of subchondral bone drilling (forage) on the cartilage repair process after injury has occurred, a cartilage defect (1 cm in diameter) was created on the radial facet of the proximal surface of each third carpal bone in 6 adult horses. In one of the third carpal bones (right or left thoracic limb) of each horse, a 1-cm cartilage defect was created, and 5 holes (1 mm in diameter and 10 mm deep) were drilled through the subchondral bone into the cancellous bone. In the other thoracic limb, an identical defect was created, but not drilled. Analyses of cell numbers and types in the synovia and the mucin precipitate quality were done before, at 1 week after, and 3 weeks after surgical manipulation was done and showed no significant difference between the joint environment of drilled carpi and those of nondrilled carpi. At 21 weeks after surgical manipulation was done, each joint was examined radiographically, macroscopically, and microscopically to compare the condition of the joints and the state of repair of the cartilage in each defect. The amount of surface of the defect covered by the dense fibrous and fibrocartilagenous repair tissue and the thickness of the repair tissue were significantly greater (P less than 0.05 and P less than 0.01, respectively) in the drilled carpal bones. In addition, the attachment of the repair tissue to underlying chondro-osseous tissue was better in the drilled carpal bones. Fibrocartilage was resurfacing the drilled defects, whereas only fibrous tissue was present in the nondrilled defects.(ABSTRACT TRUNCATED AT 250 WORDS)

Near circumferential retroperitoneal rectal tear in a pony.

A 13-year-old, 370-kg, Appaloosa gelding with mild colic of 4 days' duration was found to have a near circumferential retroperitoneal rectal tear. Accumulation of feces at the site of the repair had created a large perirectal cavity. Removal of feces and cleansing of the perirectal cavity were performed daily. Sutures were placed to stabilize, but not reappose, the torn ends of the rectum. The perirectal cavity filled with granulation tissue, and the rectal tear healed.

Erythrocyte volume distribution analysis and hematologic changes in two horses with immune-mediated hemolytic anemia.

Immune-mediated hemolytic anemia was diagnosed in two horses on the basis of regenerative anemia, increased erythrocyte fragility in hypotonic saline, autoagglutination, and a positive direct antiglobulin (Coomb's) test. During steroid therapy partial resolution of the anemia was indicated by rising packed cell volume, macrocytosis, and bone marrow erythroid hyperplasia. Using erythrocyte volume distribution histograms (erythrograms), the regenerative response was characterized by analysis of macrocytic and normocytic erythrocyte subpopulations. In both horses, a gradual net increase of about 2 X 10(6) macrocytes/microliter occurred over a four- to five-week period. Over the same interval there was a gradual decrease in the number of normocytes. We suggest that the macrocytes remained large through this period rather than contributing to normocyte population growth. Erythrograms may provide an additional means of evaluating erythrocyte regeneration in horses.