Using RetinoGraphics BPI-50 in Selected Canine Eye Disorders

Main Article Content

Kamuran Pamuk

Keywords

BPI-50, Cataract, Melanopsin, Pupillary light reflex, Retina

Abstract

Study Objectives: The objective of this study was to assess pupillary light reflexes under pen light, red light, and blue light stimuli of different intensities in the healthy eyes of dogs and the eyes of dogs with cataracts. The study examines patients with cataracts and evaluates whether there is retinal or optic nerve damage based on the pupillary response. Methods: This study used 10 healthy dogs and 10 dogs with cataracts at different stages that were sedated with tomidine (5 µg/kg). The RetinoGraphics BPI-50 (Precision Illuminator) device was used for light stimulation. Light intensities comprised pen light 570 nm (nominal), red 660 nm and blue 465 nm wavelengths. Results: The measurements by the illuminator BPI-50 with red light and blue light source revealed that the pupil diameters ​​of dogs with incipient and immature cataracts showed similarity with the eyes of healthy dogs. Under pen light and red light illumination, the pupil diameters of the dogs with mature and hypermature cataracts were similar to those obtained without using any light source. Under the blue light source, in turn, there was a significant reduction in pupil diameter. Conclusion: As an alternative to the advanced imaging techniques used in eye examination, RetinoGraphics BPI-50 (Precision Illuminator) can be used to assess pupillary light reflex for pre-diagnostic purposes. A blue light source can be used in mature and immature animals in cases where the pupillary reflex created by pen light is insufficient.

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References

1. Gelat KN Diseasesand surgery of the canine cornea and sclera. Esssen Vet Ophtalmol, 4 th Ed. USA. 125-164. Wiley Blackwell, Ames, 2005.
2. Gelat Essen Vet Ophthalmol, Lippincott Wilkins, London, 2000.
3. Ofri R. (2002). Clinical electrophysiology in veterinary ophthalmology- the past, present and future. Doc Ophthalmol, 104: 5-16.
4. Lucas RJ, Douglas RH, Foster RG. Characterization of an ocular photopigment capable of driving pupillary constriction in mice. Nat Neurosci 2001; 4(6): 621-626.
5. Panda S, Provencio I, Tu DC, Pires SS, Rollag MD, Castrucci AM. Melanopsin is required for non-image-forming photic responses in blind mice. Sci 2003; 301: 525-7.
6. Hattar S, Lucas RJ, Mrosovsky N, Thompson S, Douglas RH, Hankins MW. Melanopsin and rod-cone photoreceptive systems account for all major accessory visual functions in mice. Nature 2003; 424: 76-81.
7. Melyan Z, Tarttelin EE, Bellingham J, Lucas RJ, Hankins MW. Addition of human melanopsin renders mammalian cells photoresponsive. Nature 2005; 433 (7027): 741-745.
8. Berson DM, Dunn FA, Takao M. Phototransduction by retinal ganglion cells that set the circadian clock. Sci 2002; 295: 1070-3.
9. Wong KY, Dunn FA, Graham DM, Berson DM. Synaptic influences on rat ganglion-cell photoreceptors. J Physiol 2007; 582: 279-96.
10. Hattar S, Liao HW, Takao M, Berson DM, Yau KW. Melanopsincontaining retinal ganglion cells: architecture, projections, and intrinsic photosensitivity. Sci 2002; 295: 1065-1070.
11. Dacey DM, Liao HW, Peterson BB, et al. Melanopsin-expressing ganglion cells in primate retina signal colour and irradiance and project to the LGN. Nature 2005; 433 (7027): 749-754.
12. Gooley JJ, Lu J, Fischer D, Saper CB. A broad role for melanopsin in nonvisual photoreception. J Neurosci 2003; 23: 7093-106.
13. Chen SK, Badea TC, Hattar S. Photoentrainment and pupillary light reflex are mediated by distinct populations of ipRGCs. Nature 2011; 476:92-5.
14. Gooley JJ, Lu J, Chou TC, Scammell TE, Saper CB. Melanopsin in cells of origin of the retinohypothalamic tract. Nat Neurosci 2001; 4: 1165.
15. Hattar S, Kumar M, Park A, Tong P, Tung J, Yau KW. Central projections of melanopsin-expressing retinal ganglion cells in the mouse. J Compar Neurol 2006; 497: 326-49.
16. Hannibal J, Christiansen AT, Heegaard S, Fahrenkrug J, Kiilgaard JF. Melanopsin expressing human retinal ganglion cells: subtypes, distribution, and intraretinal connectivity. J Compar Neurol 2017; 525: 1934-61.
17. Liao HW, Ren X, Peterson BB, Marshak DW, Yau KW, Gamlin PD. Melanopsin-expressing ganglion cells on macaque and human retinas form two morphologically distinct populations. J Compar Neurol 2016; 524: 2845-72.
18. Lucas RJ, Hattar S, Takao M, Berson DM, Foster RG, Yau KW. Diminished pupillary light reflex at high irradiances in melanopsin-knockout mice. Sci 2003; 299: 245-247.
19. Guler AD, Ecker JL, Lall GS, Haq S, Altimus CM, Liao HW. Melanopsin cells are the principal conduits for rod-cone input to non-image-forming vision. Nature 2008; 453: 102-5.
20. Gooley JJ, Ho Mien I, St Hilaire MA, Yeo SC, Chua EC, van Reen E. Melanopsin and rod-cone photoreceptors play different roles in mediating pupillary light responses during exposure to continuous light in humans. J Neurosci 2012; 32: 14242-53.
21. McDougal DH, Gamlin PD. The influence of intrinsically-photosensitive retinal ganglion cells on the spectral sensitivity and response dynamics of the human pupillary light reflex. Vis Res 2010; 50: 72-87.
22. Rukmini AV, Milea Dan, Gooley JJ. Chromatic pupillometry methods for assessing photoreceptor health in retinal and optic nerve diseases. Front Neurol 2019; 10 (76): 1-20.
23. Safa R, Cuthbertson FM, Wulff K, Downers SM, Foster RG, Peirson SN. Changes in pupil area and dynamics following cataract surgery. Invest Ophthalmol Visual Sci, 2010; 51: 5397.
24. Grozdanic SD, Matic M, Sakaguchi DS, Kardon RH. Evaluation of retinal status using chromatic pupil light reflex activity in healthy and diseased canine eyes. Invest Ophthalmol Visual Sci 2007; 48 (11): 5178-5183.
25. Grozdanic SD, Kecova H, Lazic T. Rapid diagnosis of retina and optic nerve abnormalities in canine patients with and without cataracts using chromatic pupil light reflex testing. Vet Ophthalmol 2013;16: 329-340.
26. Petersen-Jones SM, Komaromy AM. Dog models for blinding inherited retinal dystrophies. Hum Gene Ther Clin Dev 2015; 26:15-26.
27. Gelatt KN, Brooks DE, Samuelson DA. Comparative glaucomatology. I: The spontaneous glaucomas. J Glaucoma. 1998; 7: 187-201.
28. Provencio I, Rodriguez IR, Jiang G, Hayes WP, Moreira EF, Rollag MD. A novel human opsin in the inner retina. J Neurosci 2000; 20: 600-605.
29. Kardon R, Anderson SC, Damarjian TG, Grace EM, Stone E, Kawasaki A. Chromatic pupil responses: preferential activation of the melanopsin-mediated versus outer photoreceptormediated pupil light reflex. Ophthalmol 2009; 116: 1564-1573.
30. Park JC, Moura AL, Raza AS, Rhee DW, Kardon RH, Hood DC. Toward a clinical protocol for assessing rod, cone, and melanopsin contributions to the human pupil response. Invest Ophthalmol Vis Sci 2011; 52: 6624-6635.
31. Grozdanic SD, Betts DM, Kardon RH. Abstract presented at: 37th Annual Meeting of the American College of Veterinary Ophthalmologists, San Antonio, TX. Abstract 37, 2006.