Comparison of the rebound tonometer (TonoVet) with the applanation tonometer (TonoPen XL) in normal Eurasian Eagle owls (Bubo bubo).
OBJECTIVE
To examine the feasibility and accuracy of a handheld rebound tonometer, TonoVet, and to compare the intraocular pressure (IOP) readings of the TonoVet with those of an applanation tonometer, TonoPen XL, in normal Eurasian Eagle owls.


METHODS
Ten clinically normal Eurasian Eagle owls (20 eyes).


METHODS
Complete ocular examinations, using slit-lamp biomicroscopy and indirect ophthalmoscopy, were conducted on each raptor. The IOP was measured bilaterally using a rebound tonometer followed by a topical anesthetic agent after 1 min. The TonoPen XL tonometer was applied in both eyes 30 s following topical anesthesia.


RESULTS
The mean +/- SD IOP obtained by rebound tonometer was 10.45 +/- 1.64 mmHg (range 7-14 mmHg), and by applanation tonometer was 9.35 +/- 1.81 mmHg (range 6-12 mmHg). There was a significant difference (P = 0.001) in the IOP obtained from both tonometers. The linear regression equation describing the relationship between both devices was y = 0.669x + 4.194 (x = TonoPen XL and y = TonoVet). The determination coefficient (r(2)) was r(2) = 0.550.


CONCLUSIONS
The results suggest that readings from the rebound tonometer significantly overestimated those from the applanation tonometer and that the rebound tonometer was tolerated well because of the rapid and minimal stress-inducing method of tonometry in the Eurasian Eagle owls, even without topical anesthesia. Further studies comparing TonoVet with manometric measurements may be necessary to employ rebound tonometer for routine clinical use in Eurasian Eagle owls.
Jeong
Man-Bok
MB
Department of Veterinary Surgery and Ophthalmology, College of Veterinary Medicine, Seoul National University, San 56-1, Sillim 9-dong, Gwanak-gu, Seoul 151-742, Korea.
Kim
Young-Jun
YJ
Yi
Na-Young
NY
Park
Shin-Ae
SA
Kim
Won-Tae
WT
Kim
Se-Eun
SE
Chae
Je-Min
JM
Kim
Jong-Taek
JT
Lee
Hang
H
Seo
Kang-Moon
KM
D000818:Animals; D007429:Intraocular Pressure; D020305:Strigiformes; D014065:Tonometry, Ocular / Q000295:instrumentation / Q000662:veterinary*