Ophthalmic Section Meeting 26th November 1999 1. BALLOON DACRYOCYSTOPLASTY STUDY S FENTON, SL

Ho, E HORAN. A MURRAY, PE CLEARY, D RYDER, G O'CONNOR

DEPARTMENT OF OPHTHALMOLOGY, CORK UNIVERSITY HOSPITAL, IRELAND

Lacrimal obstruction accounts for 3% of clinic visits. In adults it is secondary to idiopathic chronic inflammation leading to stenosis and fibrous obliteration. Treatment options include a dacrocystorhinostomy, silicon incubation, endonasal endoscopic dacrocystorhinostomy and balloon dacryocystoplasty. The aim of the study was to determine the efficacy of dacryocystoplasty with balloon dilation in the treatment of acquired obstruction of the nasolacrimal system in adults. This was a retrospective study between 1997 and 1999. The procedure involved introducing a flexible tipped guide wire through the inferior canaliculus and into the nasolacrimal system. A deflated angioplasty balloon catheter was introduced in a retrograde direction over the wire and dilated at the obstruction site. The procedure was performed in 53 eyes of 43 patients. There were 32 females and 11 males. The mean age was 58 years. The mean follow-up was 14 months. The technical success rate was 94%. The reobstruction rate was 34%. The subjective success rate was determined by a telephone questionnaire to all patients and was 51%. Metallic stents were used in five cases in an effort to improve the long term patency. The advantages of this procedure are that it is safe with a low complication rate, it is less invasive than a dacrocystorhinostomy, it can be performed as a day case and bilateral procedures can be performed simultaneously. It can reduce surgical waiting lists and free up theatre time. However, it has a high restenosis rate. Metallic stenting may improve the patency in the long term but further follow up in this group is necessary before conclusions can be made.

Initial visual acuity was 3/60 in both eyes, and examination showed bilateral severe anterior uveitis and vitritis with white choroidal infiltrates. Bilateral vitreous aspirates grew no organisms. He was treated with bilateral intravitreal and subconjunctival injections of gentamycin and intravenous ciprofloxacin and hydrocortisone. He was also treated with topical antibiotics, steroids and mydriatics. Over the next two weeks, there was an improvement of the ocular inflammation. On the 16th day, the patient's right retina detached subtotally. The patient had already arranged transport home and so he was transferred to Taiwan where he had two attempts at reattaching his right retina which failed. His left retina also later detached but this was repaired successfully. At four months, the best-corrected visual acuity is PL in the right eye and 6/12 in the left. Most cases of endogenous bacterial endophthalmitis are due to gram-positive bacteria. 1 A limited number have been reported due to the gram-negative organism K. pnuemoniae with the majority originating in Taiwan.'- Klebsiella pneumoniae is the leading cause of pyogenic liver abscess in Taiwan.' Visual prognosis is very poor with 90% of eyes having visual outcomes of counting fingers or worse.' References: 1. Okada AA, Johnson RP, Liles WC, D'Amico DJ, Sullivan Baker A. Endogenous bacterial endophthalmitis. Report of a ten-year retrospective study. Ophthalmology 1994; 101: 832-838. 2. Margo CE, Mames RN, Gyu JR. Endogenous Klebsiella endophthalmitis. Report of two cases and review of the literature. Ophthalmology 1994; 101: 1298-1301.

2. 11778&3460

4. ROBERT BOYLE PASSES ON A PROBLEM TO DR TURBERVILLE

SL Ho, G O'CONNOR

CS BREATHNACH

DEPARTMENT OF OPHTHALMOLOGY, CORK UNIVERSITY HOSPITAL, IRELAND

DEPARTMENT OF PHYSIOLOGY, UNIVERSITY COLLEGE DUBLIN, IRELAND

We reported a male (age 20 years) and a female (age 28 years) who suffered from bilateral progressive visual loss. Blood investigations including syphilis were normal. MRI brain showed high signal intensity on the side of the more visually impaired intraorbital optic nerve. DNA molecular analysis confirmed the presence of Leber 11778 and 3460 point mutation, respectively. Discussion: Leber's hereditary optic neuropathy has the age of onset ranges between three to 80 years old (peak incidence: 20-30 years old). The condition is transmitted via maternal mitochondrial inheritance. Seventy percent of affected individuals are male. Clinical features include bilateral simultaneous or sequential loss of vision down to 6/60 to no perception of light, with or without afferent pupillary defect. Fundoscopy may revealed normal looking discs or disc pseudoedema with signs of non-leaking peripapillary telangiectatic microangiopathy on fluorescein angiography. Optic atrophy may develop at later stage. It was hypothesised that the mitochondrial mutation leads to respiratory chain dysfunction and causes the extensive degeneration of retinal ganglion cell layer and optic nerve. 1 No proven effective treatment available at the present time. High dose systemic steroid may be offered. Abstinence fiom smoking and excessive alcohol is advisable. The prognosis of the condition is poor. A small number of patients may experience visual recovery (5% in 11778 and 22% in 3460 mutation). 2 In conclusion, the diagnosis of Leber's hereditary optic neuropathy should be considered in all patients with bilateral optic neuritis or atypical visual loss secondary to an optic neuropathy of undetermined aetiology, irrespective of age or sex, and mitochondrial DNA studies should be performed. References: 1. Howell N. Leber hereditary optic neuropathy: respiratory chanin dysfunction and degeneration of the optic nerve. Vision Res 1998; 38 (10): 1495-1504. 2. Taylor D. Paediatric Ophthalmology. 2nd edition. Blackwell Sciences Ltd., 1997: 709-711. 3. BILATERAL ENDOGENOUS BACTERIAL ENDOPHTHALMITIS ASSOCIATED WITH PYOGENIC HEPATIC ABSCESS B CHANG, M CAHILL. A MURRAY DEPARTMENT OF OPHTHALMOLOGY, CORK UNIVERSITY HOSPITAL, IRELAND

We document a case of bilateral endogenous bacterial endophthalmitis associated with pyogenic hepatic abscess. A 40-year-old male Taiwanese sailor initially presented with a ruptured right hepatic lobe abscess which required surgical drainage. Further treatment was with intravenous antibiotics after both pus samples and blood cultures grew Klebsiella pneumoniae. The patient later presented with bilateral endogenous endophthalmitis. 118

On 22nd June 1668 Samuel Pepys (1633-1703) went to a meeting of the Council of the Royal Society to seek Robert Boyle's advice about his sight.' The previous November, John Turlington, `the great spectacle maker [had] dissuaded me from using old spectacles, but rather young ones, [and'] from using reading glasses which do magnify much.' Spectacles obviously had not solved the problem, which he initially noticed mornings after enjoying too many 'healths'. Boylel referred him to Dr Turberville, who the next day `discoursed I thought learnedly about them, and takes time before he did prescribe me anything to think of it.' Turberville prescribed physic and eyedrops; then, on 3rd July, Pepys met the ophthalmologist at an ale-house in the Strand where Richard Lower (1631-1691), dissected `several eyes of sheep and oxen, with great pleasure — and to my great information; but strange that this Turberville should be so great a man, and yet to this day had seen no eyes dissected, or but one, but desired this Dr Louvre to give him the opportunity to see him dissect some.' Turberville was not consulted further, and in August Pepys tried a new remedy — a `Tube' incorporated in a vizard; for a few days he was pleased, but by 31st May he closed the Journal finally — so as not to `undo my eyes' any further. Retrospective diagnosis is never as infallible as hindsight. References: 1. Pepys S. The diary of Samuel Pepys. In: Latham P, Matthews W (eds). London G Bell, 1970-1983. 8: 486, 5519: 9: 248-249, 254-255, 277, 547, 564. 2. Carmichael HR. Lancet 1911; 2: 124. 5. VISUAL OUTCOME OF RETINAL DETACHMENT IN CHILDREN S ROKERYA, R ACHESON INSTITUTE OF OPHTHALMOLOGY, DUBLIN, IRELAND

A retrospective study over a period of 10 years was undertaken by the authors to evaluate the outcome of retinal detachment in the juvenile population (0-20 years). Sixty-four cases of retinal detachments in 58 patients were included in this study. Retinal detachment was associated with the following risk factors: blunt trauma (15), penetrating injuries (13), aphakia and pseudophakia (1), optic disc coloboma/hypoplasia (2) and inflammation (2). Eighteen cases had scleral buckling, 13 cases had vitrectomy and 28 had both. In five patients no retinal detachment repair was undertaken. Time between presentation and operation was from one day to one year. Twenty-six eyes required 1 operation, 19 eyes had 2 operations and 21 eyes had 3 or more operations. Successful anatomical reattachment was achieved in 53.3% of cases. Visual improvement of two lines or better was achieved in 20%: 15.3% became blind: 6.1°ío had the eye removed, 9.2% retained a blind but cosmetically acceptable eye. Irish Journal of Medical Science • Volume 169 • Number 4 • Supplement 4

Ophthalmic S 26th November 1999

We recommend retinal detachment repair be undertaken to preserve and restore vision and for cosmetic reasons.

6.

AN UNUSUAL RETINAL DYSTROPHY

VW LONG, H DEMPSEY. D MOONEY, P KENNA

intraocular implants to correct pseudophakic refractive error. Ophthalmology 1999; 106 (1): 56-59.

9.

NITRIC OXIDE INDEPENDENT VASODILATATION IN THE PORCINE POSTERIOR CILIARY CIRCULATION

RESEARCH FOUNDATION, ROYAL VICTORIA EYE AND EAR HOSPITAL, DUBLIN, IRELAND S QUINN I .2 , C O' BRIEN2 , P MCLOUGHLIN I

A 12-year-old girl presented with night blindness and visual field loss. Bestcorrected visual acuity was 6/12 right and left. Visual fields were bilaterally constricted. The fundal appearance showed an annulus of retinal pigment epithelium atrophy and pigment clumping. The annulus extended to the temporal arcades and contained a white substance subretinally. Fluorescein angiography showed corresponding areas of hypo- and hyper-fluorescence. There was no dye leakage. Electroretinography (ERG) showed an unrecordable rod isolated response. The response in the dark-adapted state to the maximal intensity flash showed a very characteristic electronegative b wave. Cone-isolated responses were delayed. Electroculography and dark adaptation were abnormal. Other family members have been examined and the family pedigree shows an autosomal recessive inheritance. This retinal dystrophy is notable because of the unusual fundal appearance and ERG findings.

7. KERATOPROSTHESIS: A CURE FOR BLINDNESS? VW LONG, W POWER OPHTHALMOLOGY DEPARTMENT, ROYAL VICTORIA EYE AND EAR HOSPITAL, DUBLIN, IRELAND

This procedure may be used as an option of last resort for severe bilateral corneal blindness when all other suitable options have been considered or attempted. It may be useful in severe ocular surface conditions and for repeated corneal graft failure. A 55-year-old man presented 27 years following severe burns from a road traffic accident. He had repeated corneal graft failures in the past with each eye. On examination, he had a right phthisical eye and left marbleised cornea. Visual acuity in his left eye was perception of light in two quadrants. Intraocular pressure was digitally normal and an ultrasound scan showed no evidence of a retinal detachment. The patient had a Dohlmann 1 keratoprosthesis procedure performed. At six weeks, the patient only achieved hand movements vision due to an optic neuropathy. The patient noticed no improvement in his vision. At three months postoperatively, there were no significant complications with the keratoprothesis. This case illustrates some of the difficulties with proper patient selection. The patient appeared to be an ideal candidate for the procedure. We hope to use this procedure on other cases that will gain a benefit from it. Common aetiologies in descending order of success with this procedure are recurrent corneal graft. rejection, trachoma, alkali burns, ocular pemphigoid and Stevens-Johnson syndrome. Complications are significant and are the reason why this procedure is only used as a last resort in bilaterally blind patients. They include extrusion, glaucoma, retinal detachment, retrospective membrane and endophthalmitis. A good result could expect 6/12 vision rehabilitation of carefully selected patients.

8. PIGGYBACK LENSES CAN CORRECT HYPERMETROPIC ANISOMETROPIA POST GRAFT TRIPLE PROCEDURE R BRENNAN, SJ MORGAN SUNDERLAND EYE INFIRMARY, UK

We report on three patients who had significant anisometropic hypermetropia post penetrating keratoplasty, extra capsular cataract extraction and posterior chamber intraocular lens. All three had a piggyback Acrysof lens placed in the ciliary sulcus as a secondary procedure. To calculate the correct lens power needed we used JL Gaytons formula whereby we multiplied the desired spherical equivalent shift by 1.S.I Two patients achieved a postoperative ani -sometrpicdfn+0.25DOepatinbcmsorpialy myopic with a difference of -3.SD. Piggyback intraocular lens implantation is a useful strategy in the management of patients who are hyperopic post triple procedure. Alternatives such as contact lenses are not always appropriate for the patient and LASIK would produce maximal thinning around the graft host junction. Reference: 1. Gayton JL, Sanders V, Van Der Karr M, Raanan MG. Piggybacking Irish Journal of Medical Science • Volume 169 • Number 4 • Supplement 4

DEPARTMENT OF PHYSIOLOGY', UNIVERSITY COLLEGE, DUBLIN, INSTITUTE OF OPHTHALMOLOGY 2 , MATER MISERICORDIAE HOSPITAL, DUBLIN. IRELAND

It is now believed that vascular dysfunction may lead to glaucomatous damage. Systemic endothelial abnormality has been noted in patients with normal pressure glaucoma.' Although nitric oxide (NO) accounts for a large proportion of vasorelaxation in the posterior ciliary circulation,'- considerable relaxation remains unexplained. We investigated the roles of haemoxygenase (HO) and cyclooxygenase (COX), which produce the vasodilators carbon monoxide (CO) and prostacyclin (PG12), respectively, in NO-independent endothelium-dependent vasodilatation in porcine posterior ciliary arteries. Isolated vascular rings were mounted on a Mulvaney-Halpern small vessel myograph for measurement of isometric tension development. Vasodilator responses to bradykinin (BK) were elicited in rings preconstricted with PGF2a in the presence of the nitric oxide synthase inhibitor L-NAME (10 -3 M) alone (controls) and in the presence of L-NAME and an inhibitor of HO or COX (test condition). Incubation with the COX inhibitor indomethacin (10 -6 M, n=6) significantly reduced NO-independent BK-induced relaxation compared to paired control (p<0.01, Student Newman Keuls). The HO inhibitor tin protoporphtrin-1X (SnPP-1X, 10 -5 M) did not reduce relaxation compared to its saline diluent (n=9), but significantly reduced relaxation when compared to protoporphyrin-1X (PP-1X, 10 -5 M, n=9), a structurally similar analogue which does not inhibit HO (p<0.01, Student Newman Keuls). We have found that a COX product (PGI2) accounts for a significant proportion of NO-independent vasodilatation. The SnPP-1X studies suggest that endogenous CO production does not a functionally significant role in the porcine ciliary circulation and that PP-1X may have some non-specific effects. The identity of the agent causing residual dilatation remains elusive. References: 1. Henry E, Newby DE, Webb DJ, O'Brien C. Peripheral endothelial dysfunction in normal pressure glaucoma. Invest Ophthalmol Vis Sci 1999; 40 (8): 1710-1714.

2 .Yao K, Tschudi M, Flammer J, Luscher TF. Endothelium-dependent regulation of vasocular tone of the porcine ophthalmic artery. Invest Ophthalmol Vis Sci 1991; 32 (6): 1791 -1798.

10. ORBITAL FALL-OUT N HORGAN, I FLITCROFT, P MORIARTY, S KENNEDY ROYAL VICTORIA EYE AND EAR HOSPITAL, DUBLIN, IRELAND

The Chernobyl nuclear power plant explosion on 26th April 1986 released a total radiation dose equivalent to 200 times that of the combined releases from the Hiroshima and Nagasaki atomic bombs. Belarus, the Ukraine and western Russia received the highest levels of radionuclide contamination. The girl whose case is presented here was born one year after the Chernobyl accident. Now aged 12, she has suffered gradually progressive bilateral proptosis since early childhood with complete loss of vision in each eye. Preoperative CT scans revealed massive intraconal lesions in each orbit arising from the optic nerves and extending to the optic canals. Preoperative examination revealed café-au-lait patches on this child's skin, while her mother also had café-au-lait patches as well as cutaneous neurofibromas. The preoperative working diagnosis was bilateral optic nerve gliomas in association with neurofibromatosis type 1. Sequential lateral orbitotomies and excision of these lesions were performed. Histology confirmed that they were low grade pilocytic astrocytomas (i.e. optic nerve gliomas). This is an unusually aggressive case of optic nerve gliomas and raises the question of whether exposure played a role in the disease course.

UL!]

Ophthalmic S 26th November 1999

11. PRACTICE STYLES AND PREFERENCES OF IRISH OPHTHALMOLOGISTS 1999 P O'BRIEN, T FULCHER

The aim of this survey was to assess current practice styles of Irish ophthalmic surgeons involved in cataract and refractive surgery, and compare these results with published data from a similar US survey. Our survey included results from 30 surgeons out of 42 surveyed (71 % response). In Ireland, the preferred method of anaesthesia for cataract surgery was peribulbar anaesthesia 33%). Both topical anaesthesia and general anaesthesia are preferred by 10% of surgeons. In the US, topical anaesthesia is the most popular form of anaesthesia (37%). Peribulbar anaesthesia is preferred by 33% whereas only 1% of surgeons preferred general anaesthesia for routine cataract extraction. For cataract surgery in Ireland, 33% of surgeons use preoperative antibiotic eye-drops and 77% use postoperative antibiotic subconjunctival injections. These figures contrast with results from the US, where 76% use preoperative antibiotic eye-drops and only 27% use postoperative antibiotic subconjunctival injections. Refractive surgery was more popular amongst US ophthalmic surgeons. The most popular method is photorefractive keratectomy (PRK), which is performed by 40% of US surgeons compared with 22% of Irish surgeons. Refererence: 1. Learning DV. Practice styles and preferences of ASSCRS members — 1998 survey. J Cataract Refract Surg 1999; 25: 852-859. )

12. CONTACT LENSES — HOW CLEAN ARE THEY REALLY? R KHAN, A BOBART, A COLLUM, LMT COLLUM PROFESSORIAL DEPARTMENT, EYE AND EAR HOSPITAL DUBLIN, ROYAL COLLEGE OF SURGEONS IN IRELAND

Soft lenses develop protein deposits associated with bacteria including gramnegative Serratia, Klebsiella, Pseudomonas, E. Coli and Acanthamoeba. We cartied out a study when an increase in the number of patients presenting with keratitis due to lens wear was noticed. Patients presented at the Accident and Emergency Department and the Contact Lens clinic with keratitis, keratoconjunctivitis and marginal infiltrates. The following data were collected: 1. Habits of hygiene and general history; 2. Swabs from lenses and lens cases; and 3. Corneal scrapings. Contact lenses are of two types: — gas permeable 1. Hard (PMMA silicone) — extended were non gas permeable 2. Soft (HEMA) monthly disposable daily disposable. A total of 37 patients were assessed (25 males: 12 females), with an age range of 21-35 years; they were mainly educated, middle class. Two patients wore hard lenses, 10 soft extended wear lenses, 23 monthly disposable lenses and 2 daily disposable lenses. All-in-one solutions for cleaning and storage were used. Most had average hygiene habits but only occasionally handwashed, and then used tap water or saliva for lenswetting. Some patients swam and handled lenses in public toilets. All stored their lens cases in the bathroom. Results showed that of the 29 symptomatic patients, 25 who presented with keratitis and corneal abscess wore soft monthly disposable extended-wear monthly disposable lenses and of these two with acanthamoeba keratitis wore daily disposable lenses. Swabs of the lens cases grew Serratia, Pseudomonas, Klebsiella, E. Coli, Enterobactes, Candida and. corneal scrapings in two grew Acanthamoeba and in two Pseudomonas. Eight asymptomatic patients' lens case grew more than one gram-negative e.g. Klebsiella with Serratia, Pseudomonas, Strepviridans and coagulase negative Staphlococcus. Our conclusion was that both symptomatic and asymptomatic patient lens cases grew more than one gram-negative organism. As these subjects are prone to corneal abrasion, keratitis is a risk. Patient education, including hygiene, starts with the optician and doctors. The hazards of using saliva and tap water for rinsing lens cases should be emphasised, as should the risks associated with swimming. Lens handling in public toilets should be prohibited. Lens cases should not be stored in bathrooms and should be changed every month. Overwear of disposable lenses and nightly wear is not advisable. Peroxide based cleaning solutions may offer the best sterilisation and, overall, daily disposable lenses may he the best option.

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Irish Journal of Medical Science • Volume 169 • Number 4 • Supplement 4