Evaluation of normal ophthalmic parameters and fundoscopic images along with the comparison of two methods of A-mode ocular ultrasonographic biometry and intraocular pressure in healthy working canines

Document Type : Full paper (Original article)

Authors

1 Ph.D. Student, Department of Veterinary Surgery and Radiology, College of Veterinary Science and Animal Husbandry, DUVASU, Mathura-281001, Uttar Pradesh, India

2 Department of Veterinary Surgery and Radiology, College of Veterinary Science and Animal Husbandry, DUVASU, Mathura-281001, Uttar Pradesh, India

3 Dog Training and Breeding Centre, Sashastra Seema Bal, Alwar-301409, Rajasthan, India

4 Department of Animal Genetics and Breeding, College of Veterinary and Animal Science, RAJUVAS, Bikaner-334001, Rajasthan, India

10.22099/ijvr.2025.49696.7451

Abstract

Background: Working canines play a very important role in assisting forces by uncovering evidences that might be missed by the human eye. To date, there is no published data on normal ophthalmological parameters for working dogs. Aims: This study aims to document normal reference ranges of ophthalmological parameters and blood pressure (BP). Additionally, the study compared the two methods of intraocular pressure (IOP) measurement and A-scan biometry, and assess correlations between IOP to both systolic blood pressure and axial globe length. Methods: The study was conducted on 18 dogs of Sashastra Seema Bal (SSB), Alwar (Rajasthan), aged 3.5-6 years, which were divided into three breed-specific groups, i.e., group 1 (Belgian Shepherd), group 2 (German Shepherd) and group 3 (Labrador Retriever) with six animals each. Schirmer’s tear test strips were used to perform the Schirmer’s tear test (STT). To measure intraocular pressure (IOP), rebound tonometry (Tonovet) and indentation tonometry (Schiotz) were used. A-scan ultrasonography was performed by contact and immersion method. Fundoscopic images were recorded using Fundus-On-Phone equipment. Results: STT values revealed non-significant differences among groups, sexes, and eyes. The cumulative mean reflected a higher reading by the rebound tonometer than the indentation tonometer. In all the three groups, a significantly longer anterior chamber depth and axial globe length were observed in the immersion method. Axial globe length was longest in the Labrador breed, followed by German Shepherd and Belgian Shepherd. Systolic and diastolic pressure were significantly different among groups. Conclusion: These breed-specific various ophthalmic parameters of working canines will be useful in the clinical diagnosis of various ophthalmic affections.

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American College of Veterinary Internal Medicine (ACVIM) guidelines (2024). Breed specific blood pressure reference values [online]. Available: https://www.vethdo. com/Docs/vethdo/bpm typical_values.html [Accessed on 6 February, 2024].
Andrade, TF; Moreno, L; Nasomento, FF; Passareli, JVGC; Dos, SRV; Da, STC; Brinholi, RB and Andrade, SF (2021). Ocular biometry and ophthalmic parameters of normal eyes in French Bulldog healthy dogs. Adv. Anim. Vet. Sci., 9: 438-441.
Andrade, SF; Palozzi, RJ; Giuffrida, R; De, CRJ; De, CSG and Fukui, RM (2012). Comparison of intraocular pressure measurements between the Tono-Pen XL ® and Perkins ® applanation tonometers in dogs and cats. Vet. Ophthalmol., 15: 14-20.
Audu, HA; Idris, SIY; Hamidu, A; Fadason, ST; Lawal, M and Bappa, M (2017). Sonographic measurements of ocular biometry of indigenous Nigerian dogs. Nig. Vet. J., 38: 140-150.
Bauer, BS and Ambros, B (2016). The effects of intravenous alfaxalone with and without premedication on intraocular pressure in healthy dogs. Can. J. Vet. Res., 80: 156-161.
Boillot, T; Rosolen, SG; Dulaurent, T; Goulle, F; Thomas, P; Isard, PF; Azoulay, T; Woods, M; Lavillegrand, S; Neveux, N; Picaud, S and Froger, N (2014). Determination of morphological, biometric and biochemical susceptibilities in healthy Eurasier dogs with suspected inherited glaucoma. PloS One. 9: 1-12.
Brooks, DE (2005). Ophthalmic examination made ridiculously simple. In 30th World small animal veterinary association world congress proceedings. May 11. https://www.vin.com/doc/?id=3854142.
Conrady, CD; Joos, ZP and Patel, BCK (2016). Review: The lacrimal gland and its role in dry eye. J. Ophthalmol., 2016: 1-11.
Estrovich, IE; Shen, C; Chu, Y; Downs, JC; Gardiner, S; Straiko, M and Mansberger, SL (2015). Schiotz tonometry accurately measures intraocular pressure in Boston type 1 keratoprosthesis eyes. Corn., 34: 682-685.
Ganesan, S and Chandrasekhara, IR (2018). Ocular ultrasonographic evaluation of cataractous and pseudophakic eyes in dogs. Turk. J. Vet. Anim. Sci., 42: 611-616.
Hamidzada, WA and Osuobeni, EP (1999). Agreement between A-mode and B-mode ultrasonography in the measurement of ocular distances. Vet. Radiol. Ultrasound., 40: 502-507.
Hamor, RE; Roberts, SM; Severin, GA and Chavkin, MJ (2000). Evaluation of results for Schirmer tear tests conducted with and without application of a topical anesthetic in clinically normal dogs of 5 breeds. Am. J. Vet. Res., 61: 1422-1425.
Klein, BEK; Klein, R and Knudtson, MD (2005). Intraocular pressure and systemic blood pressure: Longitudinal perspective: The Beaver Dam eye study. Br. J. Ophthalmol., 89: 284-287.
Kobashigawa, KK; Lima, TB; Padua, IRM; Barros, AAF; Marinho, FA; Ortencio, KP and Laus, JL (2015). Ophthalmic parameters in adult Shih Tzu dogs. Cien. Rur., 45: 1280-1285.
Kulualp, K; Yurdakul, I; Erol, H; Atalan, G and Kilic, S (2018). Measurement of intraocular pressure in clinically normal Turkish Shepherd dogs with the rebound tonometer (TonoVet®) and the applanation tonometer (Tono-Pen Vet®). Med. Wet., 74: 568-573.
LeBlanc, L; Stepien, RL and Bentley, E (2011). Ocular lesions associated with systemic hypertension in dogs: 65 cases (2005-2007). J. Am. Vet. Med. Assoc., 238: 915-921.
Leiva, M; Naranjo, C and Pena, MT (2006). Comparison of the rebound tonometer (ICare®) to the applanation tonometer (Tonopen XL®) in normotensive dogs. Vet. Ophthalmol., 9: 17-21.
Park, YW; Jeong, MB; Kim, TH; Ahn, JS; Ahn, JT; Park, SA; Kim, S and Seo, K (2011). Effect of central corneal thickness on intraocular pressure with the rebound tonometer and the applanation tonometer in normal dogs. Vet. Ophthalmol., 14: 169-173.
Sampaio, GR; Ranzani, JJT and Schellini, SA (2002). Sex, anatomy and weight on intraocular lens dioptric power calculation in dogs. Sci. Rur., 32: 263-268.
Shim, J; Kang, S; Park, Y; Kim, S; Go, S; Lee, E and Seo, K (2021). Comparative intraocular pressure measurements using three different rebound tonometers through in an ex vivo analysis and clinical trials in canine eyes. Vet. Ophthalmol., 24: 186-193.
Sini, KR; Kelawala, DN; Patil, DB and Parik, VP (2017). Ocular funduscopy of different canine breeds in India - A clinical study of 70 normal dogs. Int. Poli., 17: 328-333.
Smith, K (2014). Clinical examination and diseases of the fundus in dogs. In. Pract., 36: 315-333.
Spiessen, VL; Karck, J; Rohn, K and Meyer-Lindenberg, A (2015). Clinical comparison of the TonoVet® rebound tonometer and the Tono-Pen Vet® applanation tonometer in dogs and cats with ocular disease: Glaucoma or corneal pathology. Vet. Ophthalmol., 18: 20-27.
Trivedi, RH and Wilson, ME (2011). Axial length measurements by contact and immersion techniques in
pediatric eyes with cataract. Ophthalmology. 118: 498-502.
Wehner, A; Hartmann, K and Hirschberger, J (2008). Associations between proteinuria, systemic hypertension and glomerular filtration rate in dogs with renal and non-renal diseases. Vet. Rec., 162: 141-147.
Wilkie, DA (2001). Examination and interpretation of the fundus. In 25th annual Waltham/OSU online symposium on small animal ophthalmology proceedings. Oct, 27-28. http://www.vin.com/OSUWaltham/2001.
Williams, DL (2004). Lens morphometry determined by B-mode ultrasonography of the normal and cataractous canine lens. Vet. Ophthalmol., 7: 91-95.
Wrzesniewska, K; Madany, J and Winiarczyk, D (2018). Comparison of intraocular pressure measurement with Schiotz tonometer and Tono-Pen Vet tonometer in healthy dogs. J. Vet. Res., 62: 243-247.