Eng-Yiat Yap

Trabeculectomy for acute primary angle closure.

OBJECTIVE To analyze the results of trabeculectomy performed for all cases of acute primary angle closure (APAC). DESIGN Retrospective, noncomparative case series PARTICIPANTS Fifty-six consecutive patients who underwent trabeculectomy for APAC at two Singapore centers from 1993 through 1995. METHODS The conventional treatment for APAC is to lower intraocular pressure (IOP) medically, after which laser peripheral iridotomy (PI) is performed. However, in Asian eyes, the acute attack is often refractory to standard treatment. Trabeculectomy is occasionally performed on eyes that do not respond to medical therapy, as well as eyes with APAC that respond to medical therapy but are assessed as having underlying chronic angle-closure glaucoma. In such cases, laser PI is not performed before trabeculectomy. MAIN OUTCOME MEASURES The surgical outcome was assessed in terms of final IOP and the incidence of complications. Success was defined as final IOP less than 21 mmHg without medication, and qualified success was defined as final IOP less than 21 mmHg with medication. Patients whose IOP was more than 21 mmHg, required further glaucoma surgery, lost light perception, or whose eye became phthisical were classified as failures. RESULTS The mean follow up was 22 months (range, 6-42 months). In group A, the medical failure group (n = 32), success in IOP control was obtained in 18 patients (56.2%), qualified success was achieved in 3 patients (9.4%), and failure resulted in 11 patients (34.4%). Ten patients (31.3%) encountered early postoperative complications such as shallow anterior chamber. In group B, the medical success group (n = 24), success in IOP control was achieved in 21 patients (87.5%), qualified success was achieved in 3 patients (12.5%), and there were no cases of failure. The incidence of postoperative complications was low (4 eyes [16.7%]). In terms of IOP outcome, trabeculectomy outcome was significantly worse in group A (P<0.001, Fishers exact test). CONCLUSIONS Because there is a high risk of surgical failure and complications, trabeculectomy may not be the procedure of choice in medically unresponsive cases of APAC.

Endogenous Klebsiella endophthalmitis.

Purpose To report 4 cases of endogenous Klebsiella endophthalmitis. This disease is a rare but devastating complication of Klebsiella sepsis. Familiarity with its varied clinical presentations would aid in early diagnosis and institution of appropriate therapy.Methods We report 5 eyes of 4 patients with endogenous Klebsiella endophthalmitis from December 1995 to September 1996 and review the literature regarding previously successfully treated cases.Results The mean age of the patients was 67.5 years (range 37–85 years). One patient had bilateral involvement. At presentation, 3 eyes had a visual acuity of no perception of light (NPL) and the 1 patient with bilateral involvement had an acuity of counting fingers in one eye and 20/40 in the other. The primary source of sepsis was the pulmonary system in 2 patients, the hepatobiliary system in 1 patient and the urinary tract in 1 patient. One patient had coexisting diabetes mellitus. Two patients had a pupillary hypopyon. Local and systemic treatment with an aminoglycoside and cephalosporin was initiated. Despite treatment, 2 eyes remained NPL. One eye developed a globe perforation and was eviscerated. The patient with bilateral involvement was treated within 8 h and recovered fully with a final visual acuity of 20/20 in both eyes.Conclusion It is important to have a high index of suspicion in patients with septicaemia presenting with intraocular inflammation, especially in diabetics with suppurative liver disease, urinary tract infection or pulmonary infection. As the visual prognosis for patients with Klebsiella endophthalmitis is generally poor, early diagnosis and treatment with intravenous and intravitreal antibiotics may improve the visual outcome.

Visual outcome and complications after posterior capsule rupture during phacoemulsification surgery.

Purpose: To determine the visual outcome and incidence of complications after posterior capsule rupture during phacoemulsification surgery. Methods: Forty-four eyes of 43 patients which sustained posterior capsule rupture or zonulysis during phacoemulsification surgery between April 1993 and May 1996 were retrospectively studied. Eyes With pseudoexfoliation syndrome, traumatic cataract and myopia > 6 dioptres were excluded from the study. The mean postoperative follow-up period was 26 months (range 3 to 47 months). Results: Forty-one eyes had posterior capsule rupture and 3 eyes had zonulysis. Of these 44 eyes, 41 eyes had vitreous loss and anterior vitrectomy at the time ofsurgery or subsequently. Excluding 2 eyes with pre-existing conditions that precluded good vision, 36 out of 42 eyes (85.7%) achieved spectacle corrected visual acuity of 6/12 or better post-operatively. Of all 42 eyes, 20 had anterior chamber intraocular lens (ACIOL) implantation while the others had posterior chamber intraocular lens (PCIOL) implantation. For eyes with ACIOL, 17 out of 20 eyes (85.0%) had best corrected visual acuity of 6/12 or better. For eyes with PCIOL, 19 out of 22 eyes (86.4%) had best corrected visual1 acuity of 6/12 or better. Conclusions:Phacoemulsification surgery, even if complicated by posterior capsule rupture or zonulysis, is compatible with good visual outcome. This is provided prompt attention is paid to the management of complications

Diplopia as a complication of laser in situ keratomileusis surgery

A case is presented of a patient with high myopia who developed vertical binocular diplopia after decentred laser in situ keratomileusis (LASIK) surgery with associated decompensation of pre‐existing exophoria into an exotropia. A 40‐year‐old man underwent LASIK surgery for high myopia in his right eye. Preoperatively, he was approximately –26.00/–2.00 × 35° with visual acuity of 6/12–2 in that eye. He also had an asymptomatic exophoria. After LASIK surgery, he achieved a refraction of –3.25/–0.50 × 80° with 6/21 best‐corrected visual acuity. He also developed binocular diplopia. The ablation zone had been decentred upwards and there was also an exo‐ and hypo‐deviation of his right eye. He was able to superimpose the two images in free space with vertical and horizontal prisms. A hard contact lens also resulted in superimposition of the two images. Vertical decentration of the ablation zone can induce a vertical prism effect after LASIK surgery and result in vertical diplopia. This together with abnormal optics also caused loss of best‐corrected vision and decompensation of his pre‐existing exophoria into an exotropia.

VISUAL LOSS ASSOCIATED WITH PSEUDOXANTHOMA ELASTICUM

An 18-year-old woman with pseudoxanthoma elasticum had sudden profound bilateral visual loss, presumably as a result of optic nerve infarction caused by anemia and hypotension from massive gastrointestinal bleeding. Her central visual acuity largely recovered in her right eye, but her left eye had only hand motions acuity. During the subsequent 24 years, she underwent three separate surgical procedures for gastrointestinal bleeding. Abdominal arterial angiography showed numerous aneurysms of the gastric arteries. A subtotal gastrectomy was done, and histopathologic examination found advanced degenerative changes of the elastic lamina of the gastric arteries. At age 42 years, the patient lost residual vision in her right eye. This was caused by an extrafoveal subretinal choroidal neovascular membrane, which was obliterated with laser photocoagulation. Degeneration of elastic tissue, the primary defect in this syndrome, may cause cardiovascular complications and formation of breaks in the Bruch membrane, which are visible as angioid streaks. Ingrowth of fibrovascular tissue through angioid streaks may cause disturbances of macular function. The optic nerve ischemia and infarction associated with the profound visual loss in this patient reminds the ophthalmologist of the systemic nature of this disorder and the possibility that systemic vascular complications with massive blood loss may occur.

Outcome of late probing for congenital nasolacrimal duct obstruction in Singapore children.

Objective: To evaluate the outcome of late probing in a mixed Asian children population with congenital nasolacrimal duct obstruction (CNLDO) and whether probing was associated with an increased risk of infection. Method: A retrospective clinical study was conducted. A clinical diagnosis of CNLDO was defined in an infant who presented with a history of tearing and/or eye discharge up to 1 year of age with no other accompanying ocular pathology. All patients with a presumed diagnosis of CNLDO who had probing after 12 months of age were included in our study. Prior to probing, most patients had a trial of conservative treatment with massage and/or topical antibiotics. Intra-operative patency of probing was determined when metal to metal contact of the probe and forceps was achieved and/or when fluorescein dye was recovered from the nose after syringing. Successful probing was defined as a resolution of symptoms within 1 month after probing. Results: Seventeen patients involving 19eyes fulfilled our inclusion criteria for this study. Fourteen (82%) infants were Chinese, two Malays (12%) and the remaining one Indian (6%). There were 10 males(59%) and 7 females(41%) and the mean age at probing was 2.2 years(range, 14 months to 5years 6 months). The subjects were followed-up post-operatively for a mean duration of 21.2 months (range, 2 months to 8years). Successful probing in our series was 89.5% (17/19 eyes). Of the two eyes with persistent tearing, one resolved with massage about 9 months after the unsuccessful probing; the other was referred to the oculoplastic service for further management. Conclusion: Late probing after 13 months old appears to be an effective approach in the management of CNLDO in Asian infants.

Neuro-ophthalmological manifestations of systemic lupus erythematosus in Asian patients

Purpose: To report eight patients with diagnosed systemic lupus erythematosus (SLE) who presented with a variety of neuro‐ophthalmological complications and outcomes.

Tuberculous choroidal granulomas in a patient with systemic lupus erythematosus

Aim: We report a case of tuberculous choroidal granulomas in a patient with systemic lupus erythematosis (SLE) who developed miliary tuberculosis (TB) and bilateral granulomas while on immunosuppressive medication.Methods: The case notes of thispatient were reviewed.Results: The patient was first seen for base-line ophthalmic screening before anti-tuberculous medication was started. The patient was subsequently followed up at 2 weeks, 4 weeks and 2 months with fundal examination and photography. One choroidal granuloma was found in the right eye while another peripheral lesion involved the left eye. Both resolved in response toanti-tuberculous medication over a 2-month period with resultant chorioretinal atrophy and scarring.Conclusion: This case demonstrates the need to screen immuno-suppressed SLE patients who have miliary TB for possible eye involvement.

Pupil abnormalities on the first postoperative day after cataract surgery

Most, if not all, ophthalmologists strive to achieve a round pupil after cataract surgery with posterior chamber lens implantation. The presence of pupil abnormalities and iris modifications is cosmetically undesirable and may affect the quality of postoperative vision. The pupillary motility may be changed which will in turn affect both pupillary light reflexes and pupillary dilatation during fundus examination. In this paper, we prospectively studied 2 groups of patients who underwent uncomplicated cataract surgery with posterior chamber lens implantation; 100 patients who had planned extracapsular cataract extraction (ECCE), and 130 patients who underwent phacoemulsification. On the first postoperative day, we found a 16% rate of pupil abnormalities in the group which underwent ECCE surgery while only 5.3% of the phacoemulsification group had pupil abnormalities. There were different causes in which the two groups. The most common cause of pupil abnormality after ECCE was due to iris sphincter rupture, whereas the most common cause after phacoemulsification was due to iris trauma during phacoemulsification. These pupil abnormalities are the direct consequence of factors in surgery and we suggest ways to minimize the occurrence of such abnormalities in cataract surgery.

Visually significant opacification of hydrophilic acrylic intraocular lenses--a clinico-pathological analysis.

Purpose To describe the clinic-pathological analysis of the visually significant opacification of the Cirrus International Hydroflex™ foldable hydrophilic acrylic intraocular lens (IOL) (model SC600-2, Medical Developmental Research Inc., Clearwater, Florida) and to highlight that this IOL is the same model as the Acryflex™ SC600-2 IOL, by the same manufacturer. Methods Retrospective review of five eyes of four patients with opacification of their Cirrus International Hydroflex™ foldable hydrophilic acrylic IOLs (model SC600-2) after uncomplicated phacoemulsification and IOL implantation. Two IOLs were explanted from two patients 14 to 24 months after initial implantation. Each explanted lens was divided into equal halves, one half for scanning electron microscopy (SEM) study and the other half for transmission electron microscopy (TEM) examination. SEM and TEM samples were also subjected to energy dispersive X-ray analysis (EDX). Results The IOL opacification was detected 14 to 24 months after uncomplicated phacoemulsification and IOL implantation. EDX analysis showed that the crystals contained calcium and phosphorus, presumably calcium phosphate. Conclusions The Cirrus Inter national Hydroflex™ foldable hydrophilic acr ylic IOL (model SC600-2) is associated with opacification, that appeared worse centrally than peripherally. This is the same model as the Acryflex™ SC600-2 IOL, made by the same manufacturer. The opacification consists of calcium and phosphate.