Eye (2006) 20, 837–839 & 2006 Nature Publishing Group All rights reserved 0950-222X/06 $30.00 www.nature.com/eye 1 1 2 Neurotrophic A Lockwood , M Hope-Ross and P Chell CASE SERIES keratopathy and diabetes mellitus Abstract no history of previous corneal trauma or herpes simplex infection. Ocular examination revealed Diabetes mellitus is frequently associated a best-corrected visual acuity of 6/12 in both with microvascular complications such as eyes. There was an epithelial irregularity retinopathy, nephropathy, and peripheral extending across the inferonasal quadrant of the neuropathy. Neurotrophic keratopathy occurs right cornea. A diagnosis of exposure in response to a neuropathy of the ophthalmic keratopathy was made. She was treated with division of the trigeminal nerve. Rarely has artificial tears and a month later the epithelium diabetic neurotrophic keratopathy been had healed. A year later, an epithelial defect in described. This paper discusses the the same area was seen at follow-up. Again she ophthalmic histories of three patients who was asymptomatic and the visual acuity was presented with diabetic neurotrophic unchanged. Decreased corneal sensation was keratopathy. In one patient the corneal noted using a cotton swab to touch the ulceration was the sole presenting feature of peripheral and central cornea. A diagnosis of his diabetes. We discuss the need for increased diabetic neurotrophic keratopathy was made. vigilance in the ophthalmic community for She was treated with ocular lubricants. After suspecting diabetes in patients with 6 months, the defect had increased in size to unexplained corneal epithelial disease. 5.5 mm. There was associated corneal Eye (2006) 20, 837–839. doi:10.1038/sj.eye.6702053; neovascularisation. Weak topical steroids were published online 7 October 2005 added and with the use of occlusive padding at night, the corneal epithelial defect improved. Keywords: neurotrophic; keratopathy; diabetes After 2 months, the cornea had healed. After 2 years, the corneal epithelium had remained Introduction intact. Case 2 A 33-year-old woman with a 24-year Neurotrophic keratopathy is a condition that 1 history of insulin-dependent diabetes was seen Birmingham and Midland occurs in patients with a neuropathy affecting Eye Centre, City Hospital, by us for quarterly review. She had a past the ophthalmic division of the trigeminal nerve. Birmingham, UK history of treated proliferative retinopathy in Diabetes mellitus is a common disease associated with microvascular complications both eyes with two vitreous haemorrhages. 2Worcester Royal Infirmary, such peripheral neuropathy. Diabetes has rarely There was peripheral neuropathy with a Charles Hastings Way, Worcester, UK been associated with neurotrophic keratopathy.1 neuropathic foot ulcer. She had no ocular symptoms. On examination, she had a corrected We describe three patients with diabetic Correspondence: visual acuity of 6/12 in both eyes. There was an neurotrophic keratopathy, of which one was M Hope-Ross, Birmingham previously unknown to have diabetes, in whom epithelial defect with scalloped edge in the and Midland Eye Centre, corneal ulceration was the sole presenting inferior part of the left cornea. Corneal sensation City Hospital, Dudley Road, feature. was markedly reduced, in the left eye more than Birmingham B18 7QH, UK the right. A diagnosis of diabetic neurotrophic Tel: þ 44 121 5543801; Fax: þ 44 121 3786183. keratopathy was made. She was treated with Case reports E-mail: monique. a temporary ptosis by intramuscular botulinum hope-ross@goodhope. Case 1 A 26-year-old woman with a 10-year toxin (15 U), artificial tears, chloramphenicol nhs.uk history of insulin-dependant diabetes ointment, and temporary punctual plugs. Over developed a corneal problem. She had no the next 8 months with intensive lubricant Received: 16 December 2004 symptoms of external eye disease. She had had treatment, the ulcer gradually healed and Accepted: 28 July 2005 extensive laser photocoagulation for within 12 months the only remaining feature Published online: 7 October proliferative diabetic retinopathy, but there was was a stromal scar (Figure 1). 2005 Neurotrophic keratopathy and diabetes mellitus A Lockwood et al 838 Figure 1 Stromal scar following neurotrophic corneal ulcera- tion (case 2). Case 3 A 44-year-old man was seen by us for evaluation of corneal ulceration in both eyes. Several weeks before referral, the corneal ulcers were diagnosed. At that time, best-corrected visual acuities were 6/9-3 in the right eye and 6/5 in the left. Despite topical treatment with antibiotics, steroids, and bandage contact lenses, the condition had progressed. There was no previous history Figure 2 (a) Bilateral corneal ulcers in diabetic neurotrophic of trauma nor was there any ocular or systemic disease. keratopathy (case 3). (b) Fluorescein uptake in the corneal On ocular examination, the best-corrected visual acuities epithelial defect of the right eye (case 3). were counting fingers in both eyes. Oval epithelial ulcers extended across the visual axes of the corneas (Figure 2a and b), and the sensation was greatly reduced. There were high levels of glucose and ketones present on formation of sorbitol by aldose reductase and advanced urinalysis, and the blood glucose was 17 mmol/l. glycosylation end products may play a role. A diagnosis of diabetes mellitus and diabetic neurotrophic Neurotrophic keratopathy occurs in patients with loss keratopathy was made. There was no diabetic of sensory innervation to the cornea. This is most retinopathy. Ocular treatment was initially with alternate commonly due to virus infection, such as herpes simplex patching of the eyes together with punctual occlusion or herpes zoster, chemical injury, or trauma.4 and lubricants. Over the course of the year, the corneal Compression of the trigeminal nerve by aneurysm or epithelial defects healed and visual acuity returned to tumour may also lead to these corneal changes. Indeed, 6/6 in both eyes. experimental section of the nerve can lead to neurotrophic ulceration.5 Neurotrophic keratopathy progresses in three stages.4 The first stage is characterised by epithelial hyperplasia, Comment irregularity, and punctate epithelial erosions. There may The microvascular complications of diabetes such as be superficial neovascularistion. Stage 2 is characterised retinopathy, nephropathy and peripheral neuropathy are by a persistent epithelial defect, around which the edges well described. Diabetic retinopathy is the most common are smooth and rolled. With stromal involvement (stage cause of visual impairment among persons between 25 3), the ulcer may progress to melting and eventually and 65 years of age.2 Diabetic peripheral neuropathy, a perforation. microvascular disease, is characterised by loss of Various neuromediators are postulated to play a role in myelinated nerve fibres, wallerian degeneration, and maintaining epithelial integrity. After sensory blunted nerve fibre reproduction, the extent of which is denervation, levels of substance P and acetylcholine were associated with the duration of hyperglycaemia.3 The depleted in rat corneas.6 In vitro, substance P and mechanism is not well understood; however, the acetylcholine induce epithelial proliferation.7 Nerve Eye Neurotrophic keratopathy and diabetes mellitus A Lockwood et al 839 growth factor may induce production by sensory nerves mellitus must be considered when a patient presents of substance P and acetylcholine.8 In addition, nerve with an unexplained neurotrophic corneal ulcer. growth factor restores corneal integrity and sensation in patients with neurotrophic ulceration.9 References While rarely described, patients known to have 1 diabetes mellitus can develop neurotrophic keratopathy. 1 Hyndiuk RA, Kazarian EL, Schultz RO, Seideman S. Like neurotrophic keratopathy due to other causes, these Neurotrophic corneal ulcers in diabetes mellitus. Arch patients have decreased corneal sensation and corneal Ophthalmol 1977; 95: 2193–2196. ulcers that fail to respond to antibiotic or steroid therapy. 2 Infeld DA, O’Shea JG. Diabetic retinopathy. Postgrad Med J Little is known of the incidence or pathophysiology. 1998; 74: 129–133. 10 3 Clark CM, Lee DA. Prevention and treatment of the Schultz et al found reduced corneal sensation in 18% of complications of diabetes mellitus. N Engl J Med 1995; 332: a group of randomly selected diabetic patients. A later 1210–1217. study found a significant relationship between decreased 4 Bonini S, Rama P, Olzi D, Lambiase A. Neurotrophic vibration perception of fingers and toes between diabetic keratitis. Eye 2003; 17: 989–995. patients with keratopathy and those without, and 5 De Haas EBH. Desiccation of cornea and conjunctiva after sensory denervation. Arch Ophthalmol 1962; 67: 79–92. therefore suggested that the keratopathy was a 6 Shimizu T, Izumi K, Fujita S, Koja T, Sorimachi M, Ohba N 11 manifestation of peripheral neuropathy. Microscopic et al. Capsaicin-induced corneal lesions in mice and the examination of diabetic corneas shows that the corneal effects of chemical sympathectomy. J Pharmacol Exp Ther epithelium consists of more enlarged, pleomorphic, and 1987; 243: 690–695. irregularly arranged cells with fewer microvilli, 7 Reid TW, Murphy CJ, Iwahashi CK, Foster BA, Mannis MJ. 12 Stimulation of epithelial cell growth by the neuropeptide suggestive of impaired ability to heal. substance P. J Cell Biochem 1993; 52: 476–485. Further evidence that diabetic keratopathy is a 8 Levi-Montalcini R. The