Intraocular osteosarcoma in a dog.

A 10-year-old German shepherd dog was presented with unilateral uveitis and hyphaema. Treatment was unsuccessful and the eye was enucleated. Intraocular osteosarcoma was diagnosed by histological examination.

Familial non-rcd1 generalised retinal degeneration in Irish setters.

Four Irish setters were diagnosed with bilateral retinal degeneration and cataracts at an age ranging from six to 11 years. In three of these dogs, progressive night blindness was reported from an age of eight to 11 years. In the fourth dog, aged six, no signs of visual impairment had been noticed. In all four dogs, the rod-cone dysplasia type 1 (rcd1) mutation was excluded as a cause, using an allele-specific PCR. From their three-generation pedigrees, a familial relationship was detected in three out of four dogs, which were also related to four additional Irish setter dogs with a history and clinical signs suggestive of late-onset progressive retinal degeneration. These results suggest the existence of a possibly hereditary, late-onset, progressive retinal atrophy in the Irish setter breed, that is distinct from rcd1.

Suprascleral removal of a foreign body from the retrobulbar muscle cone in two dogs.

The successful application of a suprascleral approach to remove a foreign body within the retrobulbar muscle cone in two dogs is described. The episcleral space was entered through a small opening in the paralimbal conjunctiva and bulbar vagina. Under ultrasound guidance, a curved haemostat with a fine tip was advanced along the scleral surface to the foreign body, which was then carefully grasped and removed using gentle traction. The conjunctival incision was left to heal secondarily. The suprascleral approach may allow the quick removal of non-cutting and non-barbed foreign bodies from the episcleral space or the retrobulbar muscle cone, without the need for extensive tissue dissection. To reduce the risk of damaging extraocular tissues, the procedure must be performed cautiously and under ultrasound guidance. The globe should be continuously observed for any movement suggesting traction or pushing forces on bulbar or adjacent anatomical structures.

[Arterial hypertension in the cat. A pathobiologic and clinical review with emphasis on the ophthalmologic aspects]. / Arteriële hypertensie bij de kat. Een pathobiologisch en klinisch overzicht met nadruk op de oogheelkundige aspecten.

Arterial hypertension in cats appears to be an often underdiagnosed problem. Sudden disturbances of vision caused by intraocular haemorrhage and/or detached retina are often related to hypertension. The ability to measure blood pressure routinely in cats, by using an indirect method, has increased knowledge of feline hypertension in recent years. In cats mainly secondary hypertension is described, caused by as a consequence of renal disease, hyperthyroidism, chronic anaemia, primary aldosteronism, and a high-salt diet. This article describes the (patho) physiology of blood pressure control, the different methods of blood pressure measurements and the causes, clinical manifestations, and possibilities of antihypertensive therapy. Given our current knowledge, blood pressure should be measured regularly in older cats (> 10 years), especially in those with renal insufficiency, hyperthyroidism, or visual disturbances of unknown origin. Blood pressure measurements using the Doppler method is a relatively cheaply, quick and simple, method with enough reliability. Hence this method should be incorporated in veterinary practice.

[Progressive retinal atrophy in Abyssinian and Somali cats in the Netherlands (1981-2001)]. / Progressieve retina-atrofie bij Abessijnen en Somali's in Nederland (1981-2001).

From 1981 to 2001, 248 Abyssinian and 127 Somali cats in the Netherlands were examined for hereditary eye disease. Distinct ophthalmoscopic signs consistent with hereditary progressive retinal atrophy (PRA) were observed in 11 Abyssinian cats, and subtle signs in 3 Abyssinian cats. A familial relationship was detected in 13 out of 14 of these cats, which supports a hereditary basis to the condition. Distinct funduscopic signs of retinal degeneration were observed at a median age of 4 years. One cat with advanced retinal degeneration was only 7 months old, whereas the remaining 10 cats were between 2 and 12 years old at the time of diagnosis. These differences in the age of onset are suggestive of at least two types of PRA occurring in Abyssinian cats in the Netherlands: a dysplastic, early-onset and a late-onset retinal degeneration. A large-scale and systematic examination programme for hereditary eye disease will be necessary to assess the incidence of PRA in the Dutch population of Abyssinian and Somali cats as a whole, and to provide a basis for a preventive breeding programme.

[DNA-diagnosis of congenital diseases in companion animals and the role of the practicing veterinarian]. / DNA-diagnostiek van erfelijke ziekten bij gezelschapsdieren en de rol van de praktiserende dierenarts daarbij.

The knowledge on the impact of gene defects on the development of disease in companion animals is increasing rapidly. The gene defects may be differentiated in an initiating defect, which is the cause of illness, and a promoting defect, which enhances the chance on illness. Up till now only initiating defects are known in dogs and cats. All this is of great importance for breeding purposes, because within a breed there is narrow relationship which means the genetic diversity is small, and with all the disadvantages thereof. The identification in good time of gene defects in breeding animals, so that these animals being excluded from breeding, is of utmost importance in preventing congenital diseases. For that reason more and more the owners will appeal to veterinary surgeons to cooperate in procedures to screen potential breeding animals, or to declare the animals free from gene defects. The problems with regard to the diagnostic tests, including the DNA-tests, and their predictive values are discussed.

The effect of intravenous medetomidine on pupil size and intraocular pressure in normotensive dogs.

Medetomidine, a highly specific alpha-2 adrenergic agonist, has been demonstrated to lower intraocular pressure (IOP) in rabbits and cats when applied topically. The purpose of this study was to assess the influence of intravenously injected medetomidine on the pupil size (PS) and the IOP of non glaucomatous dogs. IOP was measured by applanation tonometry and PS was measured using Jameson calipers at t=0 (or time of IV injection of medetomidine (Domitor; Orion) at the dose of 1500 microg/m2 body surface area) and again after 5 minutes (t=5). The IV administration of medetomidine caused miosis in all 14 dogs. The mean PS decreased from 9.0 to 4.0 mm (p<0.001). The IOP was lowered in 10 dogs and in 4 dogs there was a rise in IOP. The mean IOP (mmHg) decreased from 22 to 21 (p>0.2). The data presented above confirm that medetomidine at a dose of 1500 microg/m2 body surface area produces miosis in non glaucomatous dogs, without influencing the IOP.

[Horner's syndrome in the dog: a retrospective study]. / Het syndroom van Horner bij de hond: een retrospectief onderzoek.

A retrospective study was made of 43 dogs with Horner's syndrome (HS). In the group studied the golden retriever was found to be predisposed for Horner's syndrome. No predisposition in gender or age seemed to exist. Symptomatic treatment with topical 10% phenylephrine alleviates the clinical signs. Generally patients recover in 2 to 6 months.

Persistent hyperplastic tunica vasculosa lentis and persistent hyaloid artery in a 2-year-old basset hound.

A 2-year-old Basset hound with unilateral persistent hyperplastic tunica vasculosa lentis and primary vitreous is described. There was leukokoria in the left eye, caused by bluish-white polar densities and haemorrhagic discoloration in the nucleus of the lens. Ultrasonographic examination of the eye revealed a small hyperechoic lens and a hyperechoic linear soft-tissue strand extending from the posterior pole of the lens through the optic disc. Power Doppler imaging revealed blood flow in this persistent hyaloid artery, but 5 months later, immediately prior to surgery, there was no flow in this artery. Ultrasonography, including Power Doppler imaging, was useful to confirm the diagnosis and to estimate the complications of surgery, especially the risk of vitreal haemorrhage after cutting of the persistent hyaloid artery. Comparison of the ultrasonographic images with those obtained by computed tomography suggested that the resolution of computed tomography is inadequate for identifying structures as fine as a persistent hyaloid artery.

Ultrasonographic diagnosis of persistent hyperplastic tunica vasculosa lentis/persistent hyperplastic primary vitreous in two dogs.

Ultrasonography was performed on a Basset hound and a Doberman clinically suspected of persistent hyperplastic tunica vasculosa lentis/persistent hyperplastic primary vitreous. In both dogs, hyperechoic lenses with a triangular-shaped echodense structure retrolentally were visible, and a very thin hyperechoic strand was seen penetrating the anechoic vitreous from this retrolental tissue to the area of the optic nerve. Using color Doppler imaging, blood flow was evident in parts of the retina in both dogs. With power Doppler imaging there was blood flow in the lens and hyperechoic strand of the Basset hound on the first examination; whereas, on re-examination 5 months later, this was not found. Other abnormalities, such as retinal detachment, endophthalmitis, vitreous hemorrhage, microphthalmia, and posterior neoplasia could be excluded.

Early morphogenesis of persistent hyperplastic tunica vasculosa lentis and primary vitreous (PHTVL/PHPV). Scanning electron microscopic observations.

This study provides scanning electron microscopic observations on the early morphogenesis of persistent hyperplastic tunica vasculosa lentis and primary vitreous (PHTVL/PHPV) in canine fetuses at days 28 35 postcoitum (D28 and D35). From previous studies regarding PHTVL/PHPV it is known that a retrolental plaque of fibrovascular tissue is present in eyes of affected canine fetuses from the D33 stage. The contribution of vitreous cells to the formation of the plaque is supported by the results of this study. The lens capsules at the stages described were not found to contain abnormalities such as transparent (thinner) parts or rents, as have been described for postnatal cases of PHTVL/PHPV. These findings support the hypothesis that the capsular anomalies observed in postnatal patients are secondary entities.

[Be wise--refer! Fact or fantasy?]. / Wees wijs--verwijs! Feit of fantasie?

On the occasion of his retirement as an active specialist in Surgery dr. P.H.A. Poll describes the history of the development of the specialties in Veterinary Medicine in The Netherlands and carefully looks forward. As a tribute, his specialist colleagues, all related to the Companion Animal Hospital "De Wagenrenk", publish one or more case reports from there respective disciplines (ophthalmology, surgery, radiology, dermatology).

[Hereditary eye diseases--diagnosis, therapy and prevention]. / Erfelijke oogafwijkingen--diagnostiek, therapie en preventie.

Eight hereditary eye diseases are discussed. These eight abnormalities follow the main possible patterns of inheritance. The clinical aspects and the prevention of these illnesses are discussed.