Indocyanine green angiography for examining the normal ocular fundus in dogs.

In dogs, a variety of diseases of the retina and choroid have been reported, either separately or concomitantly; however, the canine choroid is difficult to evaluate by veterinary techniques currently available. Indocyanine green (ICG) angiography is widely used in human ophthalmology, but has not been investigated for use in canine ophthalmology. The aim of this study was to apply a new approach to ICG angiography and compare the resulting angiograms with fluorescein (FLUO) angiograms of the ocular fundus in dogs. With a fundus camera equipped with an infrared-sensitive charged coupled device (CCD), we performed angiography on eight healthy beagles under inhalation anesthesia. ICG angiography enabled clear visualization of the choroidal vasculature, whereas FLUO angiography showed only the retinal vessels. At 8.4 +/- 3.6 sec after administration of ICG dye into the cephalic vein, the choroidal arteries could be seen extending radially from the optic disc, then the choroidal veins became apparent at 10.2 +/- 4.1 sec, coursing alongside the choroidal arteries. Gradual fading of the choroidal vessels began 13.2 +/- 2.2 min after the dye was administered, and overall diffuse fluorescence of the fundus appeared. Diffuse fluorescence of the fundus continued after the choroidal vessels and optic disc faded at about 58.3 +/- 5.3 min from administration of the dye. In conclusion, ICG angiography provides clear resolution and is reliable and simple, thus offering promise as a diagnostic aid for clinical evaluation of the choroid in dogs.

Anesthetic and cardiovascular effects of balanced anesthesia using constant rate infusion of midazolam-ketamine-medetomidine with inhalation of oxygen-sevoflurane (MKM-OS anesthesia) in horses.

The anesthetic sparring and cardiovascular effects produced by midazolam 0.8 mg/ml-ketamine 40 mg/ml-medetomidine 0.05 mg/ml (0.025 ml/kg/hr) drug infusion during sevoflurane in oxygen (MKM-OS) anesthesia was determined in healthy horses. The anesthetic sparring effects of MKM-OS were assessed in 6 healthy thoroughbred horses in which the right carotid artery was surgically relocated to a subcutaneous position. All horses were intubated and ventilated with oxygen using intermittent positive pressure ventilation (IPPV). The end-tidal concentration of sevoflurane (ET(SEV)) required to maintain surgical anesthesia was approximately 1.7%. Heart rate and mean arterial blood pressure averaged 23-41 beats/min and 70-112 mmHg, respectively. All horses stood between 23-44 min after the cessation of all anesthetic drugs. The cardiovascular effects of MKM-OS anesthesia were evaluated in 5 healthy thoroughbred horses ventilated using IPPV. Anesthesia was maintained for 4 hr at an ET(SEV) of 1.7%. Each horse was studied during left lateral (LR) and dorsal recumbency (DR) with a minimum interval between evaluations of 1 month. Cardiac output and cardiac index were maintained between 70-80% of baseline values during LR and 65-70% of baseline values during DR. Stroke volume was maintained between 75-85% of baseline values during LR and 60-70% of baseline values during DR. Systemic vascular resistance was not different from baseline values regardless of position. MKM-OS anesthesia may be useful for prolonged equine surgery because of its minimal cardiovascular depression in both of lateral and dorsal recumbency.

Axial correction of pes varus by transverse-opening wedge osteotomy and T-plate fixation with beta-tricalcium phosphate (beta-TCP) transplantation in dachshunds.

Axial correction was performed surgically in two miniature dachshunds presenting with lateral patellar dislocation and limping caused by pes varus. Pes varus had resulted from asymmetric closure of the physis of the distal tibia. Prior to surgery, osteotomy was simulated by measuring X-ray films to determine the distance required for the wedge opening. Transverse-opening wedge osteotomy was performed on the medial side of the distal tibia, and beta-tricalcium phosphate (beta-TCP) was inserted in a wedge shape into the area created by the cuneiform osteotomy. Finally, the tibia was fixed by a veterinary 1.5/2.0-mm T-plate. Both dogs were able to walk a few days after surgery, and the lateral dislocation of the patella normalized almost completely in about one month. At two months, X-ray films showed that the implant had remained in position without any dislocation, and the beta-TCP had fused with the surrounding bone.