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| TOP TEN 3 Don’t Skip the Fundus Examination of the fundus allows us to directly evaluate the patient’s blood vessels, nerves (optic nerve and retina), and clarity of the ocular medium (vitreous). UÊDilation: Examination of the posterior seg- ment is easiest when the pupils are dilated. Dilation is best achieved with tropicamide 1%, either alone or in combination with phenyl- ephrine 2.5%. Avoid use of atropine due to the fact that its effect lasts several days to a couple of weeks. Tropicamide, on the other hand, lasts only 4 to 6 hours. UÊInstrumentation: Using a direct ophthalmo- scope provides high magnification, but it’s analogous to looking at a cytology slide with 100× mag- nification as the first Figure 3. Indirect ophthalmoscopy performed with a penlight and 28 diopter condensing lens lens. Rather, either use indirect ophtha lmos - copy (Figure 3) or the PanOptic opht h a lmo - scope (welchallyn.com) to give you less magni- fication and a wider field of view of the fundus. Three common clinical findings of the fundus are retinal: UÊ i}iniÀ>Ìion UÊ imoÀÀh>}ià UÊ iÌ>VhminÌ° Often times a dog is referred for cataract evalua- tion when the real reason the patient is losing vision is due to inherited retinal atrophy. In these patients, the cataracts are secondary and, therefore, cataract removal will not improve vision as the retina will degenerate, eventually causing blindness. Signs of retinal atrophy include tapetal hyperreflectivity and vascular attenuation or absence. Another common clinical presentation is an aged cat with sudden vision loss; evaluation of this patient’s fundus may reveal multifocal retinal and vitreal hemorrhages as well as retinal detachment. These findings indicate that the patient’s blood pressure should be evaluated for possible systemic hypertension. 4 64 Uveitis—How Do We Know? Practitioners are often confused about the term uveitis.3 Uveitis results when the iris and cili- ary body blood vessels are inflamed and allow leak- age of vessel contents, including cells, protein and, sometimes, fat (ie, diabetic uveitis). Other than non- specific findings, such as redness and cloudy eyes, there are 3 basic signs that identify possible uveitis: Today’s Veterinary Practice July/August 2011 UÊ iVÀi>Ãi`ÊinÌÀ>oVÕl>ÀÊ«ÀiÃÃÕÀiÊ UÊ µÕioÕÃÊvl>ÀiÊ>n`ÊVillÃÊ UÊ*ÀiÃinViÊ ovÊ kiÀ>ÌiVÊ «ÀiVi«iÌ>ÌiÃÊ Figure 4), especially in cats. Aqueous f lare is simply protein that has escaped from leaky vessels; if the vessel holes are large enough, cells or even whole blood can enter the ante- rior chamber. Flare and cells can be found with a slit beam of light from a direct ophthalmoscope, PanOptic ophthalmoscope with a slit beam feature, inexpensive slit beam devices, or a hand-held slit lamp biomicroscope. The light beam within the anterior chamber will look cloudy if there is protein, cells, or both. Magnification helps locate cells float- ing in the aqueous humor; however, if you see cloud- iness in the aqueous humor, it’s protein and/or cells. Keratic precipitates are cells that precipitate on the corneal endothelium. They are most often found inferiorly and in cats. 5 Young Dog, Squinty Eye A young dog (usually about 2 years old) pres- ents with a very squinty eye. Often times it’s a golden retriever, bulldog, shih tzu, Lhasa apso, or bichon frise. You examine the eye and think you see a superficial erosion toward the superocentral aspect of the cornea. However, the squinting is making it difficult to tell for sure. One hint to help a patient relax for a more thorough examination is to apply a couple of spaced drops of proparacaine. If you don’t see anything obvious causing the pain and erosion, such as a foreign body or entropion, consider an ectopic cilium. To clarify, this is not distichia—extra eyelashes along the lid margin.4 While many of these patients will have distichiasis, an ectopic cilium is a single hair protruding from the underside of the eyelid through the conjunctiva. Treating…Ectopic Cilium Treatment of ectopic cilium requires, under general anesthesia, removing the hair follicle en bloc and freezing the residual tissue. r 4UBCJMJ[F UIF FZFMJE XJUI B DIBMB[JPO DMBNQ TP UIF abnormal area is easier to see and handle. r 8JUI B NN TLJO QVODI EP B QBSUJBM UIJDLOFTT punch around the follicle and use a small blade to remove the tissue. r 6TF B DSZPVOJU UP GSFF[FmUIBXmGSFF[F UIF BSFB and a small cautery to control any oozing. r 5IF QBUJFOU XJMM GFFM CFUUFS JNNFEJBUFMZ Figure 4. Keratic precip- itates located inferiorly in eye with anterior uveitis