One-year results of photodynamic therapy for small predominantly classic choroidal neovascular membranes secondary to age-related macular degeneration.

PURPOSE: To determine the visual and angiographic outcomes of patients with small predominantly classic choroidal neovascular membranes (CNV) undergoing photodynamic therapy (PDT). METHODS: The subjects were a cohort of patients with age-related predominantly classic CNV with lesion size of greatest linear diameter of 2000 microm or less treated with PDT. Lesion size and visual acuity were recorded at baseline and at 3-month intervals. Visual treatment failure was defined as either loss of at least 15 letters or visual acuity less than 35 letters on a modified Early Treatment Diabetic Retinopathy Study chart. Lesion treatment failure was defined as increase in greatest linear diameter (GLD) of at least 500 microm. RESULTS: Twenty-five eyes of 25 patients were included. Visual treatment failure occurred in 16 and mean visual acuity dropped from 58 letters to 34 letters (p<0.0001). In 11 of these patients this occurred within the first 3 months. Lesion treatment failure occurred in 18 patients. Mean GLD increased from 1331 to 2935 microm (p<0.0001). Early growth of the lesion was associated with poor visual outcome with growth in GLD in the first 3 months of 310 microm in patients without eventual visual treatment failure and 1131 microm in patients with eventual visual failure (p=0.027). CONCLUSIONS: Small predominantly classic lesions commonly cause visual deterioration if treated with PDT alone. In the first year over 50% may lose at least 15 letters or drop below 35 letters, with most visual loss occurring in the first 3 months. Visual loss is associated with early lesion growth.

White-centered retinal hemorrhages as an early sign of preeclampsia.

PURPOSE/METHOD: We examined a pregnant patient who had symptomatic white-centered retinal hemorrhages. Severe preeclampsia rapidly developed despite the patient not having hypertension, proteinuria, or edema at initial examination. RESULTS/CONCLUSIONS: Retinal hemorrhages gradually resolved without treatment and visual acuity returned to 20/20 six months after emergency delivery of a healthy infant. Retinal or choroidal vascular abnormalities in pregnant patients may be caused by early preeclampsia and immediate obstetric referral is indicated.

Vitrectomy for phacolytic glaucoma in a patient with homocystinuria.

PURPOSE: To determine the successful treatment of unilateral phacolytic glaucoma by vitrectomy and trabeculectomy in a patient with homocystinuria whose lens had dislocated into the vitreous at least 15 years earlier. METHODS: In a 32-year-old woman with homocystinuria, bilateral dislocation of the lens into the vitreous, and phacolytic glaucoma in her left eye a three-port pars plana vitrectomy was performed with the patient under general anesthesia. The lens was removed and a trabeculectomy fashioned. Special precautions for general anesthesia included preoperative aspirin and compression stockings for thromboembolic prophylaxis and intraoperative dextrose infusion, 5%, to maintain intravascular volume and prevent hypoglycemia. RESULTS: The intraocular pressure and uveitis resolved postoperatively with improvement in the visual acuity and intraocular pressure, which returned to normal without further treatment. CONCLUSIONS: Phacolytic glaucoma is best resolved by removal of the exciting lens material. Pars plana vitrectomy with the patient under general anesthesia can be carried out safely despite the risks traditionally associated with homocystinuria.

Effectiveness of apraclonidine 1% in preventing intraocular pressure rise following macular hole surgery.

AIM: To determine the efficacy of apraclonidine hydrochloride 1% in preventing intraocular pressure (IOP) spikes following idiopathic macular hole (IMH) surgery with platelet adjunct and intraocular gas tamponade. METHODS: This is a prospective, double masked, randomised study to compare apraclonidine hydrochloride 1%, an alpha(2) agonist, with a placebo in the prevention of IOP rises following macular hole surgery. Each patient was randomly selected to receive either the study drug or the placebo; one drop was instilled in the conjunctival sac 2 hours preoperatively and on completion of the procedure. IOP was measured at baseline and at 1, 3, 6, 24, 48 hours, and 2 weeks postoperatively. Blood pressure and heart rate were also recorded at baseline and at 3 and 24 hours postoperatively. Macular hole repair surgery was performed as standardised in the unit with a vitrectomy, platelet concentrate, and complete fill of the vitreous cavity with perfluoropropane gas (C(3)F(8)) at a concentration of 16%. RESULTS: 25 patients (26 eyes) were enrolled. 12 eyes received apraclonidine hydrochloride 1% (mean age 70.7; range 62-78 years) and 14 eyes received the placebo (mean age 70.0; range 57-81 years). At baseline evaluation the mean IOP was 15.6 mm Hg for the study group and 14.3 mm Hg for the placebo group. The mean postoperative IOP at 1 hour, 3 hours, 6 hours, and 24 hours was 10.6, 9.6, 8.2, and 14.0 mm Hg in the apraclonidine group. In the control group at the same time intervals the mean IOP was 23.4, 17.5, 19.2, and 24.7 mm Hg. These readings were statistically significant different: 1 hour (p=0.0001); 3 hours (p=0.0015); 6 hours (p<0.0001); and 24 hours (p=0.019), the readings at 48 hours and 2 weeks were not statistically significant different (p=0.15 and p=0.59). Only one of the patients in the study group had an IOP above 25 mm Hg at any time. In the control group an IOP above 25 mm Hg was found in seven patients (50%) at the 1 hour postoperative measurement. At 2 weeks the IOP was recorded below 25 mm Hg in all patients. No statistically significantly difference was noted between the two groups regarding the systolic or diastolic blood pressure values and the heart rate records. No local or systemic adverse reactions were observed. CONCLUSIONS: Apraclonidine hydrochloride 1% appears to be an efficacious and safe drug in the prophylaxis of early postoperative IOP elevations in patients undergoing macular hole surgery.

Silicone oil removal. I. The effect on the complications of silicone oil.

The results of a retrospective study of the effects of silicone oil removal from 85 eyes in 85 patients are reported. Pars plana vitrectomy and fluid/silicone oil exchange had been undertaken for retinal detachments associated with giant retinal tears or with proliferative vitreoretinopathy in all cases. Clinically significant cataract developed in 60% of lenses that were clear at the time of oil removal, and 85% of pre-existing lens opacities progressed. Removal of oil from 19 eyes with uncontrollable glaucoma was combined with drainage surgery in 14 eyes. Postoperatively the intraocular pressure was controlled in 13. Corneal decompensation either improved or was unchanged in eight out of nine patients after silicone oil removal, and three patients had penetrating keratoplasty and maintained a clear corneal graft. Patients who did not have glaucoma or keratopathy at the time of silicone oil removal did not develop these complications.

Silicone oil removal. II. Operative and postoperative complications.

A retrospective study of the effects of silicone oil removal was carried out on 85 patients who had undergone pars plana vitrectomy and silicone oil exchange for giant retinal tears or proliferative vitreoretinopathy. Silicone oil was removed either as part of the treatment of anterior segment complications such as glaucoma and keratopathy (25 patients) or in order to prevent these complications (60 patients). The major complications of the removal of silicone oil were retinal redetachment (25%), hypotony (16%), and expulsive haemorrhage (1%). The length of time that the oil remained in the eye and the presence of anterior segment complications did not appear to have an effect on the rate of retinal redetachment or hypotony.

Retinal pigment epithelial detachments in the elderly: classification and outcome.

Sixty-four eyes of 57 elderly patients with pigment epithelial detachments (PEDs) were studied with the aim of describing their morphological features and identifying prognostic factors. They were classified into four groups according to the following characteristics: early fluorescence, late fluorescence, shallow detachment with limited fluorescence ('drusen type'), irregular fluorescence. The following conclusions were drawn: 30% developed demonstrable subretinal new vessels; all groups except the drusen type were susceptible, the irregular group being particularly prone. 10% developed retinal pigment epithelial tears, and these occurred almost exclusively in the slow fluorescent group. Flattening of PEDs was a feature of drusen type and early fluorescent groups. Most patients lost vision. RPE tears occurred within a few months of presentation with immediate loss of vision; likewise rapid loss of vision followed the development of demonstrable new vessels, though not necessarily in those with changes thought to imply the presence of new vessels. Flattening after prolonged detachment was associated with pigment epithelial atrophy and invariable loss of vision. Visual acuity was maintained consistently only in those eyes with persistent detachment.

Choroidal malignant melanoma in an albino.

This is the first report of an amelanotic melanoma arising in the unpigmented choroid of a tyrosinase-positive oculocutaneous albino (TPOCA). Melanosomes within the tumour showed a maturation arrest in the unpigmented type II (premelanosome) phase. Other neural crest derived melanocytes in iris and choroid showed similar limited melanogenesis. The neuroectodermally derived melanocytes of the iris, ciliary body, and retinal pigment epithelium (RPE) contained mature melanosomes, though clinically the RPE was pale. The significance of this tumour arising in an albinotic eye is discussed.

Assessment of colour vision as a screening test for sight threatening diabetic retinopathy before loss of vision.

AIM: To assess the effects of sight threatening diabetic retinopathy (STDR) on colour vision and to evaluate automated tritan contrast threshold (TCT) testing for STDR screening before significant visual loss. METHOD: Patients were recruited from a hospital based photographic screening clinic. All subjects underwent best corrected Snellen visual acuity (BCVA) and those with 20/30 vision or worse were excluded. Automated TCT was performed with a computer controlled, cathode ray tube based technique. The system produced a series of sinusoidal, standardised equiluminant chromatic gratings along a tritan confusion axis. Grading of diabetic retinopathy was made by one of the team of experienced ophthalmic registrars (SpR) using slit lamp biomicroscopy and a 78D lens; HbA(1c) and urine albumin were also tested. RESULTS: Patients with STDR had significantly worse TCT despite normal BCVA (p<0.0001). TCT yielded a sensitivity of 100% for detecting diabetic maculopathy and 94% for STDR with a specificity of 95%. Logistic regression analyses showed that TCT (p<0.001) and HbA(1c) (p<0.05) correlated significantly with the presence of STDR but duration of diabetes, urine albumin counts, and BCVA failed to show any significant correlation. No associations between TCT and duration of disease, TCT and HbA(1c), and TCT and urine albumin counts were found. CONCLUSION: Tritan colour vision deficiency was observed in patients with STDR despite their normal BCVA. These results indicate that automated TCT assessment is an effective and clinically viable technique for detecting STDR, particularly diabetic maculopathy, before visual loss.

Screening for CMV retinitis using chromatic discrimination thresholds and achromatic contrast sensitivity.

BACKGROUND: Many patients with cytomegalovirus retinitis (CMVR) are unaware of visual disturbance so screening is advocated for patients with HIV and low CD4 counts. Many tests of retinal function have been recommended but few are effective at detecting CMVR. We assess the potential of chromatic discrimination thresholds and achromatic contrast sensitivity as screening tests for patients with CMVR. METHOD: 11 HIV+ patients with CMVR, 16 age matched HIV+ patients, and 29 age matched controls were recruited. Visual acuity, chromatic discrimination thresholds, and achromatic contrast sensitivity were measured. Fundal examination was performed by slit lamp biomicroscopy for HIV+ patients. Those with CMVR were photographed and the CMVR graded from the photographs. RESULTS: Loss of chromatic discrimination was found in patients with CMVR (tritan p<0.0005, red/green p<0.05). The same group had deterioration in achromatic contrast sensitivity at 2.2, 3.4, and 10 cpd (p<0.05). There was correlation between the zone of CMVR with chromatic gratings (tritan r=0.83, p<0.005). No statistically significant difference was found between the HIV+ patients and the controls for all tests (p>0.1). CONCLUSIONS: HIV+ patients with CMVR have a loss of chromatic discrimination and achromatic contrast sensitivity and this may be used to screen HIV+ patients for CMVR.

Endophthalmitis after routine intra-ocular surgery in an asplenic patient.

A 72-year-old asplenic man developed an acute early pneumococcal endophthalmitis after a routine endocapsular cataract extraction with poor final visual outcome. It is recognized that splenectomy increases the risk and severity of pneumococcal infections. Our patient had not received pneumococcal vaccination or been prescribed prophylactic antibiotics since his splenectomy or at the time of surgery. Failure of these measures to occur may have affected visual outcome.

Changes in chromatic and achromatic contrast sensitivities following tropicamide administration.

PURPOSE: To investigate the effects of tropicamide on chromatic and achromatic contrast sensitivities over the physiological range of spatial frequencies. METHODS: A total of 26 healthy volunteers, with a mean age of 32 years, were examined with and without one drop of 1% tropicamide being administered 30 min previously. On each occasion, acuity and pupil diameter were recorded, and chromatic and achromatic contrast sensitivities were examined using the Sussex Grating Machine. RESULTS: Following tropicamide administration mean pupil diameter increased from 4.1 mm to 7.2 mm (P<0.001), and mean BCVA was reduced by 0.07 LogMar units (P<0.001). Achromatic contrast sensitivity was significantly reduced following tropicamide administration at 2.20 cycles per degree (cpd) (P=0.01), 3.40 cpd (P=0.01), 10 cpd (P=0.04), 17 cpd (P=0.04), and 25 cpd (P<0.01). There was no difference in contrast sensitivity at lower spatial frequencies (0.33 and 0.66 cpd). Chromatic contrast sensitivity was not significantly altered when tested along the red-green and tritan confusion axes. CONCLUSIONS: Achromatic contrast sensitivity is significantly reduced following tropicamide administration at intermediate and high spatial frequencies. No significant changes were seen at low spatial frequencies and in chromatic contrast sensitivities.

Vitreous haemorrhage without obvious cause: national survey of management practices.

AIM: We undertook a national survey to establish the management of dense vitreous haemorrhage without obvious cause. METHODS DESIGN: Cross-sectional anonymous self-reporting survey of ophthalmic practitioners within three target groups: vitreoretinal specialists (VRS), nonvitreoretinal specialists (NVRS), and associate specialists (AS). INTERVENTION: Presentation of the hypothetical scenario of a patient presenting with recent onset (fresh) vitreous haemorrhage with no retinal view and no apparent cause on history taken at presentation. OUTCOME MEASURES: The relative importance assigned by respondents to eight examination techniques at presentation. The proportion of respondents stating that they would review patients and perform B-scan examination at or prior to 2 weeks after presentation. The stated time to surgical intervention by VRS, and the time to referral by NVRS and AS. RESULTS: VRS ranked B-scan examination higher than AS (P<0.001). A total of 98.1% of VRS indicated that they would next review patients within 2 weeks of presentation, this figure fell to 86.5% for NVRS and 47% for AS (P<0.001). A 98.1% of VRS indicated that they would next perform B-scan ultrasound within 2 weeks of presentation, this figure fell to 88.9% for NVRS and 70.6% for AS (P<0.001). The mean time to surgical intervention by VRS was 9.5 weeks without retinal tear demonstrated on B-scan, 1.7 weeks with retinal tear demonstrated on B-scan and 1 week with retinal detachment demonstrated on B-scan. The mean time to referral by NVRS was 6.7 weeks and by AS was 11.9 weeks. CONCLUSIONS: Vitreoretinal specialists considered B-scan the most important examination tool, and typically perform B-scan early and frequently after presentation. Non-VR ophthalmologists (particularly associate specialists) review patients and perform B-scan ultrasound later and less often than vitreoretinal specialists. We recommend early referral to VR specialists, as reported referral even in uncomplicated cases would often be outside the timeframe within which VR specialists would typically choose to operate.

Surgical management of iris defects with prosthetic iris devices.

PURPOSE: To evaluate the safety and efficacy of surgical implantation of prosthetic iris devices in patients with iris deficiency. METHODS: Nine patients with traumatic iris defects, congenital aniridia or iris coloboma, and surgical or optical iridectomies were included in a noncomparative case series. Cataract surgery with intraocular lens and prosthetic iris implantation was performed in 10 eyes. The visual acuity, subjective degree of glare disability, postoperative anatomic results, and intraoperative and postoperative complications were evaluated. RESULTS: The mean follow-up was 17.75 months (range 4-48 months). Best-corrected visual acuity improved in nine of 10 eyes (90%) and remained unchanged in one eye. Glare subjectively improved in four of five eyes (80%) of patients complaining of glare preoperatively. All eyes achieved the desired anatomic result. Intraoperative complications included one anterior capsular tear. Postoperative complications included a short period of mild postoperative anterior uveitis in four eyes. Secondary glaucoma was absent. CONCLUSION: In patients with iris deficiency, implantation of prosthetic iris device, and intraocular lens implant following cataract surgery appears to be safe and effective in reducing glare disability and improving visual outcomes.

Decentration of the posterior chamber lens implant: a comparison of capsulorhexis with endocapsular surgery.

The optical effect of posterior chamber lens decentration is a well-recognised complication of cataract surgery causing significant symptoms even with the larger-diameter implant optics available. In this paper we present the results of a study of implant decentration occurring with extracapsular surgery, in which we compared a group of patients with one tear in the anterior capsule with a second group with two tears in the anterior capsule. Our findings show that lens decentration is greater in those patients with two tears of the anterior capsule, and this difference is statistically significant.

Retinal dialysis: are we missing diagnostic opportunities?

AIMS: To review medical records of those patients managed by our department for retinal dialysis, and establish whether the initial assessment had been adequate to make the diagnosis. That is, to establish if an adequate initial assessment had been performed that would reasonably exclude the likelihood of retinal dialysis and other trauma-related sequelae such as angle recession. METHODS: A retrospective review was made of all patients managed for retinal dialysis at Sussex Eye Hospital between 20 March 1997 and 20 September 2002 (66 months). In addition to general demographic data, surgical management and outcome, patient files were reviewed for history of trauma, prior ophthalmic review, and whether such review included documentation of peripheral retinal examination and gonioscopy. RESULTS: A total of 580 primary procedures were performed for retinal detachment during the review period, of which 32 eyes of 29 patients underwent surgery for retinal dialysis (6%). There were 21 male and eight female patients, with a history of trauma obtained in 55% (17 eyes, 16 patients). Of the 16 patients with prior trauma, nine had undergone prior ophthalmic review at the time or soon after their trauma; however, only 2 (22%) had documented evidence of indented peripheral retinal examination. Only one (3%) patient in the whole series had documented gonioscopy. CONCLUSIONS: Patients with history of trauma often present at the time or soon after their injury (eg hyphaema, orbital fractures). Thus, an opportunity exists to screen patients for known sequelae of trauma such as retinal dialysis and angle recession. It was disappointing to learn that this opportunity was not always being utilized, with some patients consequently developing macula-off retinal detachments and potential for reduced visual outcome.

A comparative study of the efficacy of 2.5% phenylephrine and 10% phenylephrine in pre-operative mydriasis for routine cataract surgery.

It is common practice in many ophthalmic units to administer multiple applications of 10% phenylephrine in combination with an anti-cholinergic agent to ensure adequate pupil mydriasis prior to routine cataract surgery. Phenylephrine is a pure alpha-1 adrenoreceptor agonist known to produce marked systemic vasoconstriction and associated hypertension with occasional profound reflex bradycardia. Many reviews have suggested caution in the use of 10% phenylephrine in the elderly or hypertensive patient. In a prospective, randomised trial we have assessed pupil dilation comparing the efficacy of 10% phenylephrine (53 patients) versus 2.5% phenylephrine (62 patients). When administered in conjunction with 1% cyclopentolate four times over 1 hour pre-operatively, 2.5% phenylephrine was found to be as effective as 10% phenylephrine in the initiation and maintenance of mydriasis during both extracapsular and phacoemulsification cataract extraction.

May I bend down after my cataract operation, doctor?

We reviewed the records of 21 patients with posttraumatic wound dehiscence following cataract surgery to establish the cause of injury and assess the complications and outcome following injury. Wound dehiscence most commonly resulted from patients knocking their eye accidentally with their own hand, and falls were the second most frequent cause. None of these patients suffered injury as a result of bending down. Eyes that had undergone cataract surgery through corneal sections were more prone to wound dehiscence than those operated on via a limbal approach. The visual outcome following repair was good in the majority of cases, but eyes with expulsion of lens implant and/or vitreous loss tended to have a relatively poor outcome.