Objective—To compare mean healing times after
debridement, debridement with grid keratotomy, and
superficial keratectomy in cats with nonhealing
Animals—29 cats with 36 nonhealing corneal ulcers.
Procedure—Medical records of cats with nonhealing
corneal ulcers were reviewed. Signalment, duration
of clinical signs, ophthalmic abnormalities, and
response to various treatment protocols were
Results—Mean age of affected cats was 7 years, 8
months. Affected breeds included domestic shorthair
(17 cats), Persian (9), Himalayan (2), and Siamese (1).
Clinical signs were evident for approximately 2 weeks
prior to referral. Both eyes were affected in 4 cats.
Mean healing time of ulcers treated with superficial
debridement was 30 days. Mean healing time of
ulcers treated with superficial debridement and grid
keratotomy was 42 days. Superficial keratectomy was
performed on 2 eyes and resulted in a healing time of
2 weeks. Formation of a corneal sequestrum was evident
in 2 of 21 eyes treated with superficial debridement.
Formation of a corneal sequestrum was evident
in 4 of 13 eyes treated with superficial debridement
and grid keratotomy.
Conclusions and Clinical Relevance—Brachycephalic
cats appear to be predisposed to developing
nonhealing corneal ulcers. The combination of superficial
debridement and grid keratotomy did not
decrease mean healing time of nonhealing ulcers,
compared with superficial debridement alone. Grid
keratotomy may predispose cats with corneal ulcers
to develop a corneal sequestrum. (J Am Vet Med
Objective—To compare intraocular pressure (IOP)
measurements obtained with a rebound tonometer in
dogs and horses with values obtained by means of
applanation tonometry and direct manometry.
Animals—100 dogs and 35 horses with clinically normal
eyes, 10 enucleated eyes from 5 dogs, and 6 enucleated
eyes from 3 horses.
Procedures—In the enucleated eyes, IOP measured
by means of direct manometry was sequentially
increased from 5 to 80 mm Hg, and IOP was measured
with the rebound tonometer. In the dogs and
horses, results of rebound tonometry were compared
with results of applanation tonometry.
Results—For the enucleated dog and horse eyes, there
was a strong ( r2 = 0.99) linear relationship between
pressures obtained by means of direct manometry and
those obtained by means of rebound tonometry. Mean
± SD IOPs obtained with the rebound tonometer were
10.8 ± 3.1 mm Hg (range, 5 to 17 mm Hg) and 22.1 ±
5.9 mm Hg (range, 10 to 34 mm Hg) for the dogs and
horses, respectively. Mean IOPs obtained with the
applanation tonometer were 12.9 ± 2.7 mm Hg (range,
8 to 18 mm Hg) and 21.0 ± 5.9 mm Hg (range, 9 to 33
mm Hg), respectively. Values obtained with the rebound
tonometer were, on average, 2 mm Hg lower in the
dogs and 1 mm Hg higher in the horses, compared with
values obtained with the applanation tonometer.
Conclusions and Clinical Relevance—Results suggest
that the rebound tonometer provides accurate
estimates of IOP in clinically normal eyes in dogs and
horses. (J Am Vet Med Assoc 2005;227:244–248)
Objective—To characterize the clinical and morphologic
aspects of aqueous humor misdirection syndrome
(AHMS) in cats and provide a hypothesis
regarding its pathogenesis on the basis of detailed
analysis of affected cats.
Animals—32 cats (40 eyes).
Procedure—Medical records of cats in which AHMS
was diagnosed from July 1997 to August 2003 were
reviewed. In certain cats, results of additional diagnostic
testing were also obtained, including A-scan,
B-scan, and high-resolution ultrasonography; streak
retinoscopy; video keratometry; and infrared neutralizing
videoretinoscopy as well as results of analysis of
flash-frozen sections and histologic examination of
Results—Cats had a uniformly shallow anterior
chamber, intact lens zonules, and a narrowed
approach to an open iridocorneal angle. Mean age of
affected cats was 11.7 years (range, 4 to 16 years),
and female cats were significantly more often affected
than male cats. Clinical signs included mydriasis,
decreased pupillary light reflex, decreased menace
response, and blindness. Glaucomatous changes to
the optic nerve, incipient cataracts, and eventual
blindness were seen. Intraocular pressure was ≥ 20
mm Hg (range, 12 to 58 mm Hg) in 32 of 40 eyes.
Ultrasonography and histologic examination revealed
a thickened anterior vitreal face interposed between
the lens and ciliary body, partial ciliary cleft collapse,
and cavitated vitreal regions. Various treatment
modalities were used.
Conclusions and Clinical Relevance—AHMS affects
older cats, especially females, and may result in glaucoma,
vision loss, and signs of ocular pain. Topical
administration of carbonic anhydrase inhibitors
decreased intraocular pressure. (J Am Vet Med Assoc