![]() Rob Lowe CertVOphthal MRCVS |
![]() Natasha Mitchell CertVOphthal MRCVS |
Downland Veterinary Group provides a referral service for veterinary surgeons in the south and east of England who have problem eye cases. Animals are also referred that require specialised instrumentation for diagnostic or surgical procedures. Veterinary surgeons throughout Hampshire, West Sussex and Surrey, as well as those from as far afield as Dorset, Wiltshire, Berkshire and East Sussex, regularly refer cases for assessment.
Ophthalmology is a discipline that requires specialised instrumentation in order to perform a thorough examination of the eye. This equipment is very expensive and is thus not readily available at many practices. Downland Veterinary Group has one of the best equipped ophthalmology units in private practice in our area.
The range of specialised diagnostic equipment includes Slit Lamp Biomicroscopy, Tonopen Applanation Tonometry, Direct and Indirect (monocular and binocular) Ophthalmoscopes, Gonioscopy, Ultrasonography, and Blood Pressure measurement facilities.
Ophthalmologists do it in the dark ;-)
Ophthalmoscopy is used to examine the fundus of the eye (i.e. the retina and optic nerve head). Direct ophthalmoscopy uses a small hand held instrument that allows great magnification of the structures at the back of the eye. By turning a wheel on the direct ophthalmoscope, lenses of different strength can be used to assess elevations or depressions in the fundus, or can be used to examine other structures (such as the vitreous, lens, iris or cornea) in detail. Although great magnification is provided, the area that can be visualised at any one time is small. The advantage of indirect ophthalmoscopy is that much larger areas of the retina can be examined at one time, although the image is less magnified. Monocular indirect ophthalmoscopy is performed with a light source (such as a Finhoff transilluminator or pentorch) and a condensing lens. The light is shone into the eye and the lens is placed just in front of the cornea, allowing a view of the back of the eye. Binocular indirect ophthalmoscopy requires much more specialised equipment in the form of a head set equipped with a light source and optics that allows the image to be split and hence examined by both eyes. This allows stereoptic (three dimensional) examination to be performed which is more sensitive for detecting elevations in the retina (e.g. retinal detachment) or optic nerve head (e.g. papilloedema).
Gonioscopy is an essential technique to diagnose the cause of glaucoma. To determine the cause of glaucoma it is essential to examine the drainage outflow pathway to see if there are any abnormalities present. The drainage angle runs around the inside of the eye at the point where the cornea (the clear window) meets the sclera (the white of the eye). Unfortunatly this angle is not able to be directly examined in dogs because the cornea too flat. In order to examine the angle, a small lens (a goniolens) is used which bends the rays of light out of the eye so that the drainage angle can be examined. Topical anaesthesia is applied to the eye and the lens is placed on the cornea. The angle can then be inspected using a slit lamp for magnification. The procedure is painless and is easily accomplished in most conscious animals without sedation. Gonioscopy is also used for other investigations when the peripheral areas of the eye need to be examined, such as in some tumours and inflammations.
The Veterinary Surgeons who work within the Downland Veterinary Group refer cases internally on a daily basis. Veterinary Surgeons from other practices can contact the DVG at any time in an emergency. They can also contact the reception at the Emsworth Surgery between 8.30am and 6.30pm weekdays to arrange appointments for their cases to be referred.
The Downland Veterinary Group regrets that
second opinion cases must be referred by a Veterinary Surgeon
in the normal ethical way, and that we are unable to accept cases other than in this manner
Urgent cases can be seen the same day in most situations, and less urgent cases usually within a day or so. We provide maps and directions by fax or first class post if necessary.
Veterinary Surgeons who wish to refer cases to us are welcome to contact us by telephone in the usual way. For ease of referral we have forms available to ensure that all relevant clinical information is provided, and these are available in advance on request. Case histories are happily accepted by fax, but please contact us initially before transmission in case of fax error.