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Persistent Hyaloid Arteries Kirit Patel Describes Two Cases Where Previous Sight Loss in One Eye Made the Prognosis in the Other All the More Critical

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Persistent Hyaloid Arteries Kirit Patel Describes Two Cases Where Previous Sight Loss in One Eye Made the Prognosis in the Other All the More Critical Clinical Persistent hyaloid arteries Kirit Patel describes two cases where previous sight loss in one eye made the prognosis in the other all the more critical Figure 1 Left eye corneal scarring and complete vascularisation Figure 2 Greyish white fibrous membrane indicating previous new vessels 35-year-old insulin well as cotton-wool spot be prescribed an intraocular lens or a dependent diabetic ● Right optic disc had greyish white contact lens and her only choice was patient from Nigeria fibrous membrane indicating previous a lenticular spectacle lens for distance was advised by her new vessels on the disc (Figure 2) and reading. She was also prescribed a sister to have a thorough ● Right temporal retina revealed a magnifier for reading. eye examination. Her much larger fibrous membrane and a In this patient’s case the new vessels Asister was concerned that she needed much smaller membrane on the nasal regressed following treatment and the thick glasses and a magnifier to read. aspect as well – again remnants of regression of the new vessels led to a Her sister, who was six years older previous new vessels on the retina fibrous tissue which was noticed on the and one of our patients, also suffered ● There were numerous occluded disc and elsewhere on the retina. It was from diabetes and was very diligent in retinal veins showing cattle track blood unfortunate that she lost her sight due controlling her sugar level. flow to poor diabetes control in her younger The patient had lost her right eye 10 ● Inferior branch retinal artery days. How often do we see young years ago following a corneal infection showing possible occlusion and calibre diabetics losing their sight and in some but she could not remember exactly change. cases suffering from strokes or cardiac the cause. Over the past 10-12 years ● The retina had pan-retinal problems due to their poor compliance she had undergone numerous laser photocoagulation and remnants of with instructions? treatments and a successful aphakic laser scars. cataract operation. Both eyes had CASE 2 trabeculectomy operations for glaucoma Decision taken and the left eye was treated with topical The patient was told that owing to Persistent hyaloid artery and Alphagan eye drops as well as Maxitrol the loss of the left eye she could not hyaloid membrane steroid eye drops when necessary. A 76-year-old Russian patient came for his routine diabetic assessment. He Spectacle prescription recalled losing the sight in his right eye R +11.00DS / -1.00DC X 180 VA 6/36 following a karate kick some time in Add +4.00DS VA N24. his youth. He had cataract in his left eye L no light perception. and had had a right cataract extraction some 20 years ago. For his diabetes he Ocular findings took metformin and vitamins A, C and ● Bilateral intraocular pressures were E plus bilberry. 22mmHg ● Left eye corneal scarring and Spectacle prescription complete vascularisation – no fundus R count fingers in outside corner. view possible (Figure 1) L -8.75DS / -1.00DC X 40 VA 6/12 ● Right eye cataract extraction and no and N5 (without specs). intraocular implant (aphakia) ● Right eye revealed R1 retinopathy Figure 3 Right vitreous shows the hyaloids membrane Ocular findings consisting of a few haemorrhages as behind the implant ● Right eye pseudo-aphakia and 30 | Optician | 15.10.10 opticianonline.net Clinical Figure 5 OCT scan of macular Figure 4 The hyaloid artery has a central portion and two extended arms area intraocular implant would have been traumatic. The left eye ● Right vitreous shows the hyaloid cataract was in the early stages so no membrane clearly behind the implant. intervention was necessary. The patient This is seen as central triangular was coping well with his high myopic membrane and another less clear correction and without for reading. His membrane on the left to this triangular optic disc cupping was suspect so it was piece (Figure 3) suggested that he had visual field test ● Right fundus shows a persistent and nerve fibre analysis to eliminate hyaloid artery extending from the optic glaucoma. The epiretinal membrane disc. A shiny white bright image is due was light and there were no reasons to to the hyaloid membrane which we expect problems in the future. observed on the anterior imaging thin, delicate coat that runs from the ● The hyaloid artery is seen in Discussion pars plana to the posterior surface much greater detail using the retinal The hyaloid artery is a branch of the of the crystalline lens. The posterior assessment module (RAM) which ophthalmic artery which extends from hyaloid membrane is close to the inner shows the membrane much more the optic disc through the vitreous limiting membrane of the retina and clearly. The hyaloid artery has a central humour and to the lens at the front. it is common to see posterior hyaloid portion and two arms extending from This artery supplies nutrients to the membrane detachment occurring it (Figure 4) lens in the growing foetus. In the 10th with a ring of Weiss representing ● The chorioretinal scarring inferior to week of embryological development full posterior vitreous detachment the disc is also evident and this could the lens starts to grow independently or peri-foveal vitreous detachment be related to the myopia or it could be and the hyaloid artery regresses (Figure 6 shows a hyaloid membrane related to the trauma following the while its proximal portion remains as detachment – author has named this as karate kick the central artery of the retina. The a pseudo operculum). ● Macula appears unclear regression of the hyaloid artery creates ● Right and left eye showing R0 a clear zone through the vitreous called Useful reading retinopathy and intraocular pressures the Cloquet’s or hyaloid canal. In some 1 Andres B, Jean-Marie Parel, Fabrice within normal range of 14mmHg in the patients the hyaloid artery may not Manns. Evidence for posterior zonular right eye and 16mmHg in the left eye regress fully and the remnant is called fiber attachment on the anterior hyaloid ● Left eye early posterior subcapsular persistent hyaloid artery. membrane. Investigative Ophthalmology cataract The anterior hyaloid membrane seen and Visual Science 2006, 47, 4708-4713. ● Left myopic disc with chorioretinal is a layer of collagen separating the 2 Foos RY. Posterior vitreous detachment. changes surrounding anterior vitreous from the crystalline Trans Am Acad Ophthalmol Otolaryngol ● The left disc appears fairly cupped lens. The posterior hyaloid membrane 1972; 76: 480. and suspect especially when we view separates the retina from the vitreous. 3 Heegaard S. Structure of the human the veins superiorly and inferiorly Hence the hyaloid membrane is a vitreoretinal border region. Ophthalmolgica bayoneting the edge of the cup 1994; 208: 82-91. ● Left maculr epiretinal membrane 4 Snead MP, Snead DRJ, Mahmood A, Scott (Figure 5). JD. Vitreous detachment and the posterior hyaloid membrane: a clinicopathological Decision taken study. Eye, 1994; 8: 204-209. The patient was reassured that he had 5 Streeten BW. The zonular insertion; a no diabetic retinopathy in either eye scanning electron microscopic study. Invest and his right eye could have been lost Ophthalmol Vis Sci, 1977;16:364–375. due to myopia or it could have been the karate kick and the cataract that ensued Figure 6 Hyaloid membrane detachment ● Kirit Patel practises in Radlett, Herts 32 | Optician | 15.10.10 opticianonline.net.
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