Omentalisation in the treatment of sublumbar abscessation: long-term outcome in 10 dogs.

The objectives of this study were to report the technique of omentalisation for the management of sublumbar abscessation associated with suspected migrating plant material, the intraoperative and postoperative complications that occurred and the long-term outcome of the cases. A retrospective case series of dogs (n=10) with sublumbar abscessation managed by exploration and drainage combined with omentalisation of the abscess cavity is reported in this study. The sublumbar area was approached through a ventral midline coeliotomy, the abscess was explored, drained, debrided and subsequently packed with omentum. One dog sustained an aortic rupture during exploration of the abscess, the aorta was repaired; there were no postoperative complications. There was long-term (>12 months) resolution of clinical signs in all dogs. Drainage and omentalisation of sublumbar abscesses resulted in complete resolution of signs in all dogs and was associated with a low incidence of complications. Omentalisation is an effective treatment for dogs presenting with sublumbar abscesses associated with suspected migrating plant material.

Accuracy evaluation of a two-wire technique for osteotomy positioning in the tibial plateau levelling procedure.

OBJECTIVE: To evaluate a tibial plateau levelling osteotomy (TPLO) saw blade positioning technique and to retrospectively evaluate the accuracy of the osteotomy position. METHOD: Preoperative and postoperative radiographs of 72 cases that had a TPLO surgery using a two-wire technique were reviewed. Three measurements (A1, B1, C1) were obtained in preoperative planning using a computer template system (Orthoview Vet) which mapped the intended osteotomy position. The postoperative radiographs were analysed to determine the variability of these three measurements (A2, B2, C2) and therefore the accuracy of the osteotomy. RESULTS: On average the least variable measurement was B2 (5%) followed by C2 (7%) and then A2 (13%). The maximum mean difference between the intended position and achieved position was 1.5 mm. CLINICAL SIGNIFICANCE: Despite there being a significant difference between the intended and the actual position of the osteotomy, the variation between the intended and actual tibial tuberosity width was small (5%). None of the cases suffered a tibial tuberosity fracture, which also supports the clinical value of this technique. Care must be taken to avoid inadvertent cutting of the Kirschner guide wires.

Otitis media in five cats associated with soft palate abnormalities.

The medical records of five cats that were diagnosed with otitis media and soft palate abnormalities, three of which had concurrent otitis interna, were reviewed retrospectively. The animals presented with unilateral or bilateral otitis media or otitis interna associated with soft palate hypoplasia (four cases) or unilateral soft palate cleft (one case). Otitis media was confirmed by radiography, CT or MRI. The soft palate abnormalities present were discovered on oropharyngeal examination at induction of anaesthesia. These five cases provide additional support of a link between otitis media and soft palate abnormalities in cats, as reported in humans and dogs.

A retrospective study of tibial plateau translation following tibial plateau levelling osteotomy stabilisation using three different plate types.

OBJECTIVE: To retrospectively evaluate mediolateral translation of the proximal tibial segment (tibial plateau) after tibial plateau levelling osteotomy (TPLO), stabilised with three types of plate. METHOD: Pre- and postoperative radiographs of 79 dogs that had TPLO surgery using three different types of plates were reviewed. Two plate types incorporated non-locking screws: Slocum (22 cases) and Orthomed Delta (33 cases) plates. The third plate type incorporated locking screws: Synthes TPLO Locking Compression Plate (LCP) (24 cases). The radiographs were viewed by three Diplomate surgeons who were blinded to the type of implant used. Medial or lateral translation of the proximal tibial plateau relative to the tibial diaphysis was assessed and measured at the lateral tibial cortex at the osteotomy site. RESULTS: Mean lateral translation of the tibial plateau was significantly greater when using the Synthes TPLO LCP with locking screws (+2.1 mm) compared to the non-locking Slocum (+0.4 mm) or Orthomed Delta (0.0 mm) plates. CLINICAL SIGNIFICANCE: The use of the Synthes TPLO LCP will maintain a malalignment of the tibial plateau. Accurate alignment of the tibial plateau must be ensured prior to application of the Synthes TPLO LCP.

A role for molecular oxygen in the formation of DNA damage during the reduction of the carcinogen chromium (VI) by glutathione.

Although well-established as carcinogens, the way in which chromium (VI) compounds exert their carcinogenic, mutagenic, and DNA-damaging potential remains obscure. It is clear that inside cells chromium(VI) is activated to its ultimate carcinogenic form by reducing agents including glutathione (GSH). The present study is intended to clarify if Fenton mechanisms are likely to be important in the formation of DNA lesions by chromium(VI) in combination with GSH. In buffer solutions which were treated to remove Fenton-active metal ions as well as in those not further purified, chromate and GSH induced similar numbers of single-strand breaks (SSB) in isolated PM2 DNA. Molecular oxygen was found to be essential for the formation of SSB, but chromium(V) species arising from chromate/GSH, unless activated by oxygen, appeared to be unreactive toward DNA. Upon addition of Mn(II) to solutions of chromium(VI) and GSH a diminution of Mn(II) ESR signals was observed, good evidence for the presence of chromium(IV) species. Using gas chromatography/mass spectrometry in selective ion-monitoring mode and high-performance liquid chromatography with electrochemical detection, we were able to show that Cr(VI)/GSH failed to induce base modifications typical of hydroxyl radical attack on DNA. Experimental conditions which readily induced SSB gave rise to the formation of chromium-DNA adducts, clearly demonstrating that the generation of these two DNA lesions is not mutually exclusive. We conclude that models which ascribe the induction of chromium-DNA adducts to chromium(V) and the generation of oxidative DNA damage including SSB to hydrogen peroxide are oversimplistic. It is not necessary to invoke a mechanism requiring the presence of added hydrogen peroxide to account for the ability of Cr(VI)/GSH to cause SSB. Our findings suggest that the combination of GSH, molecular oxygen, and chromium(VI) can damage DNA via non-Fenton pathways.