Macular translocation

Therapy of Pseudoxanthoma Elasticum: Current Knowledge and Future Perspectives

Pseudoxanthoma elasticum (PXE) is a rare, genetic, metabolic disease with an estimated prevalence of between 1 per 25,000 and 56,000. Its main hallmarks are characteristic skin lesions, development of choroidal neovascularization, and early-onset arterial calcification accompanied by a severe reduction in quality-of-life. Underlying the pathology are recessively transmitted pathogenic variants of the ABCC6 gene, which results in a deficiency of ABCC6 protein. This results in reduced levels of peripheral pyrophosphate, a strong inhibitor of peripheral calcification, but also dysregulation of blood lipids. Although various treatment options have emerged during the last 20 years, many are either already outdated or not yet ready to be applied generally. Clinical physicians often are left stranded while patients suffer from the consequences of outdated therapies, or feel unrecognized by their attending doctors who may feel uncertain about using new therapeutic approaches or not even know about them. In this review, we summarize the broad spectrum of treatment options for PXE, focusing on currently available clinical options, the latest research and development, and future perspectives.

Inhibition of Hypoxia-Inducible Factor-1α and Vascular Endothelial Growth Factor by Chrysin in a Rat Model of Choroidal Neovascularization

Age-related macular degeneration (AMD) is a leading cause of irreversible vision loss among the elderly population. Vascular endothelial growth factor (VEGF) is essential for choroidal neovascularization (CNV) development in advanced, wet AMD. Chrysin (5,7-dihydroxyflavone) is a natural flavonoid with anti-inflammatory, anti-oxidative, and anti-angiogenic effects. We hypothesized that intravitreally injected chrysin may inhibit CNV due to its inhibitory effect on angiogenesis. To determine the effects of chrysin on an experimental CNV model, we induced CNV in Brown Norway rats with a diode laser. One week later, rats were injected intravitreally with chrysin in the right eye and vehicle in the left eye. The following week, we evaluated chrysin’s effects via the CNV grade assessed with fluorescein angiography and histologic analyses. Hypoxia-inducible factor-1 alpha (HIF-1α) and VEGF expression in the retina/choroid complex were also measured in both eyes. The mean CNV grade was significantly lower in chrysin-treated vs. control eyes (2.34 ± 1.14 vs. 2.97 ± 1.05, p < 0.001), as was the mean CNV thickness (33.90 ± 4.89 vs. 38.50 ± 5.43 μm, p < 0.001) and mean HIF-1α and VEGF levels (both p < 0.001). Compared to chrysin-treated eyes, the relative risk of control eyes developing high-leakage lesions was 2.03 (95% confidence interval: 1.46–2.83). Since chrysin inhibited laser-induced CNV and downregulated HIF-1α and VEGF expression, it is a candidate for treating wet AMD and other CNV-associated conditions.

Inhibitory Effect of Chrysin (5,7-Dihydroxyflavone) on Experimental Choroidal Neovascularization in Rats

PURPOSE

The aim of this study was to evaluate the effect of chrysin on laser-induced experimental choroidal neovascularization (CNV) in a rat model.

METHODS

Male brown Norway rats were anesthetized, and a diode laser was used to break Bruch's membrane. One week later, each rat was intravitreally injected with 5 µl of 15 mg/ml chrysin, and CNV development was determined by fluorescein angiography at 2 weeks. The effect of chrysin on experimental CNV was assessed by fluorescein angiography and histology.

RESULTS

Two weeks after laser treatment, the intensity of fluorescein leakage from the photocoagulated lesions decreased significantly compared with the control group (p = 0.044). When the lesions were categorized into low- and high-leakage groups, there was a significant correlation between chrysin treatment and degree of leakage (p = 0.028). Compared with the chrysin-treated group, the relative risk of developing high-leakage lesions in the control group was 3.18. The mean CNV thickness was significantly thinner in chrysin-treated eyes than in control eyes (34.13 ±.0.88 vs. 37.76 ± 0.90 μm, p = 0.005).

CONCLUSION

Chrysin has an inhibitory effect on CNV in an experimental rat model, indicating that chrysin should be further evaluated for its potential as a therapy for CNV in age-related macular degeneration and in other vision-threatening conditions associated with CNV.

Visual function 5 years or more after macular translocation surgery for myopic choroidal neovascularisation and age-related macular degeneration

PURPOSE

To evaluate the changes in the best-corrected visual acuity (BCVA) after 1 year and after ≥ 5 years after macular translocation for age-related macular degeneration (AMD) or myopic choroidal neovascularisation (mCNV).

METHODS

The medical records of 61 consecutive patients who underwent macular translocation with 360° retinotomy for AMD (35 eyes) or mCNV (26 eyes) were reviewed. Overall, 40 patients, 17 mCNV and 23 AMD, were followed for at least 5 years. BCVA and area of the Goldmann visual field (VF) measured before, 12 months after surgery, and at the final visit.

RESULTS

In the 23 AMD eyes followed for ≥ 5 years, the mean preoperative BCVA was 1.149 ± 0.105 logMAR units, which significantly improved to 0.69 ± 0.06 logMAR units at 1 year (P<0.001). This BCVA was maintained at 0.633 ± 0.083 logMAR units on their final examination. In the 17 eyes with mCNV followed for ≥ 5 years, the mean preoperative BCVA was 1.083 ± 0.119 logMAR units, which was significantly improved to 0.689 ± 0.121 logMAR units at 1 year (P = 0.001). This BCVA was maintained at 0.678 ± 0.142 logMAR units on their final examination. The area of the VF was significantly decreased at 12 months and did not change significantly thereafter.

CONCLUSIONS

Our results show that macular translocation surgery significantly improves the BCVA and significantly decreases the VF area of eyes with mCNV or AMD after first 1 year. The BCVA and VF area do not change significantly from the values at 1 year for at least 5 years.

Intraocular properties of a repository urokinase receptor antagonist a36 Peptide in rabbits

PURPOSE

To evaluate the intraocular properties of A36, a peptide that directly antagonizes the cell surface urokinase receptor and so prevents pericellular urokinase plasminogen activator activity.

METHODS

A total of 41 rabbits were used. The toxicity study tested three doses of A36: 1 mg/ eye, 0.3 mg/eye, and 0.1 mg/eye. At 2 and 12 weeks, eyes were evaluated by ERG and histology. Pharmacokinetics were studied in rabbit eyes with the dose of 1 mg/eye in two different formulations: a micronized preparation and a non-micronized formulation. Eyes were enucleated at months 1, 2, 3, 4, and 5. Vitreous, retina, and choroid were collected separately for active A36 analysis.

RESULTS

We did not find ocular toxicity with low and medium doses. At the highest dose, there was a transient toxicity at 2 weeks but was not notable at 3 months. The target choroid concentration of A36 was chosen as > or =100 nM. The micronized formulation at months 1, 2, and 3 combined, showed variable levels in the choroid giving 5/10 (50%) of the therapeutic level; the non-micronized formulation at months 4 and 5 combined, gave 6/7 (86%) of the therapeutic level, although this difference was not statistically significant.

CONCLUSION

A36 appears to be long lasting; the non-micronized formulation of A36 gave concentrations above therapeutic level in the choroid at months 4 and 5. Optimization of the formulation of A36, particularly the particle size, may result in a promising new compound for exudative age-related macular degeneration treatment.

Full macular translocation versus photodynamic therapy with verteporfin in the treatment of neovascular age-related macular degeneration: 1-year results of a prospective, controlled, randomised pilot trial (FMT-PDT)

BACKGROUND

The purpose of this study was to compare full macular translocation (FMT) with photodynamic therapy (PDT) in the treatment of neovascular age-related macular degeneration (AMD).

METHODS

In a prospective, randomised, non-masked, mono-center, pilot-trial, 50 eyes of 50 patients were assigned to either FMT or PDT. Baseline and control examinations in 3-monthly intervals over a 12-month period included standardized protocol refraction, visual acuity testing and fluorescein angiography. Primary outcome measurements were made to establish the change in distant visual acuity from the baseline to the 12-month examination. The statistical analyses were carried out on the intent-to-treat principle.

RESULTS

The improvement of one or more ETDRS lines was 56% (14/25) of the eyes in the FMT and 16% (4/25) of the eyes in the PDT arm (P = 0.007). Twenty eyes (80%) in the FMT and 16 eyes (64%) in the PDT group had less than three ETDRS lines of vision loss (P = 0.35). Retinal detachment (six eyes) and diplopia (five patients) were recorded in the FMT group. None of the eyes treated in the FMT group had phtysis.

CONCLUSION

This pilot study showed that no statistically significant difference existed between the FMT and PDT in terms of the vision loss of less than three ETDRS lines in eyes with neovascular AMD. The chance of vision improvement was significantly higher for the patients in the FMT group. However, in the era of promising therapy with anti-vascular endothelial growth factor for neovascular AMD, FMT should not be offered as a standard primary procedure for neovascular AMD.

Quality of life in a prospective, randomised pilot-trial of photodynamic therapy versus full macular translocation in treatment of neovascular age-related macular degeneration--a report of 1 year results

PURPOSE

To assess visual function and its effects on vision-targeted, health-related quality of life (QOL) of patients with neovascular age-related macular degeneration (AMD) treated with photodynamic therapy (PDT) or full macular translocation (FMT).

METHODS

Fifty patients with predominantly classic subfoveal choroidal neovascularisation (CNV) secondary to AMD were randomised to PDT or FMT. To test the vision-targeted QOL, the 39-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25 plus supplement) was administered prior to and 1 year after therapy. The change of vision-related QOL at 1 year in comparison to baseline was defined as primary end point.

RESULTS

The vision-related subscales showed a stabilisation or even higher mean scores at 1 year in both treatment groups. A significant improvement in the quality of the subject's vision-related subscales was only observed after FMT correlating with a more frequent increase in visual acuity. Comparing the results of the QOL scores after 1 year, the improvement of the subscale scores general vision (p = 0.03), mental health (p = 0.02) and dependency (p = 0.03) were significantly higher in the FMT arm.

CONCLUSIONS

FMT and PDT can achieve a stabilisation in vision-related QOL, in which FMT was superior to the PDT after 1 year. The discrepancy between the amount of patients with an increased visual acuity after FMT and a moderate improvement in QOL might be caused by the onset of complications related to this surgical procedure. Besides visual acuity, the impact of therapy-related complications has to be taken into consideration when evaluating new therapeutic concepts in exudative AMD.

EFFECT OF A NOVEL OCTAPEPTIDE UROKINASE FRAGMENT, A˚6, ON EXPERIMENTAL CHOROIDAL NEOVASCULARIZATION IN THE MONKEY

PURPOSE

To evaluate the inhibitory effects of a urokinase-derived octapeptide, A 6, on laser-induced choroidal neovascularization (CNV) in monkeys.

METHODS

Twenty female cynomolgus monkeys were randomly grouped into weekly or monthly A 6 treatment groups, each consisting of 10 animals. CNV was induced in both eyes by perimacular laser treatment. In each right eye, a single 22.25-mg A 6 dose (monthly group) or 4 22.25-mg A 6 doses each week (weekly group) were given by intravitreal injections. Each left eye received phosphate buffer on the same schedule. Monkeys were observed for 4 weeks by ophthalmic examinations, color photography, and fluorescein angiography.

RESULTS

Weekly treated eyes had a 35% reduction of CNV compared with controls (P = 0.23). In contrast, monthly treated eye had a 71% reduction of CNV compared with controls (P = 0.0009). There was no evidence of toxicity at both clinical and pathologic examinations.

CONCLUSIONS

Intravitreal A 6 injections effectively inhibited CNV in cynomolgus monkeys without evidence of toxicity. The overall reduction in CNV was greater for monthly treated eyes than for weekly treated eyes. This study suggests that A 6 has promise as a local antiangiogenic treatment of CNV. Further work is indicated to evaluate the potential role of A 6 in therapy for human CNV associated with age-related macular degeneration.

Surgical management of age-related macular degeneration

The development of increasingly refined vitreoretinal surgical techniques has resulted in a variety of surgical procedures for age-related macular degeneration (AMD). These have included submacular surgery with removal of choroidal neovascular membranes and subretinal blood, intraoperative lysis of feeder vessels, pneumatic displacement of subretinal blood and macular translocation surgery. The goals of these procedures have been to improve upon the poor natural history of exudative AMD and restore useful central vision. This article reviews the varied approaches, results and complications of the surgical management of AMD.

Intraocular properties of urokinase-derived antiangiogenic A6 peptide in rabbits

To investigate the intraocular properties of an antiangiogenic peptide, A6, a total of 70 New Zealand rabbit eyes were used. For the toxicity study, 0.05 mL of 0.459 M or 0.148 M A6 was injected intravitreally; right eyes received A6, and left eyes received a vehicle. Serial intraocular pressure measurement, slit lamp, and indirect ophthalmoscopy were performed. The rabbit eyes were evaluated by fluorescein angiography, electroretinography, and histology after the scheduled sacrifice. The pharmacokinetics of an intravitreal A6 (0.05 mL of 0.488 M) and a subtenon A6 (0.5 mL of 0.305 M) injection was studied. There was no toxicity observed following the 0.148 M A6 intravitreal injections. In 2 eyes with a 0.459 M A6 intravitreal injection, focal retinal pigmentary change was observed at the injection site, which was contacted by the hyperosmolar drug bolus. Choroidal A6, following the intravitreal injection, remained therapeutic (>or=10 microM) for 72 hours. The vitreous half-life was 19.4 hours. Choroidal concentrations following the subtenon injection were minimal. The low choroidal concentrations observed may relate to the polar nature of A6. More hydrophobic analogs of A6 are likely to cross the retina more efficiently. However, in diseased eyes, in the area of choroidal neovascularization (CNV), the fluid-filled, damaged, edematous retina may permit the drug to enter the choroid in higher concentrations.

Change in visual function after macular translocation with 360° retinectomy for neovascular age-related macular degeneration

OBJECTIVE

To measure the change in vision and visual outcomes at 12 months after macular translocation with 360 degrees retinectomy (MT360) and silicone oil tamponade in patients with bilateral vision loss resulting from subfoveal choroidal neovascular membranes in age-related macular degeneration (AMD).

DESIGN

A prospective, interventional, consecutive, noncomparative case series.

PARTICIPANTS

Sixty-four patients with bilateral vision loss resulting from neovascular AMD.

METHODS

Eligible patients had AMD with subfoveal choroidal neovascularization in the operative eye and a maximum of 6 months of central vision loss. Preoperative and 12-month postoperative evaluations included standardized testing of near and distance acuity and reading speed. Patients underwent MT360 with silicone oil tamponade, followed 2 months later by extraocular muscle surgery and silicone oil removal.

MAIN OUTCOME MEASURES

Change in distance acuity, near acuity, and reading speed at 12 months after MT360 compared with those values before surgery.

RESULTS

Sixty-one patients were followed up for 12 months. All eyes were translocated successfully. Median distance acuity letter score improved from 62 letters (Snellen equivalent of approximately 20/125) before surgery to 69 letters (approximately 20/80) by 12 months after surgery (P = 0.03). Median near acuity improved from 0.70 logarithm of the minimum angle of resolution (logMAR) units (approximately 20/100) before surgery to 0.44 logMAR units (approximately 20/55) at 12 months (P<0.001). Median reading speed improved from 71 words per minute (wpm) before surgery to 105 wpm at 12 months after surgery (P<0.001). At 12 months, distance acuity improved by 1 or more lines in 32 patients (52%). In patients with either preoperative distance or near acuity of 20/80 or better, 74% and 95% of patients, respectively, remained in this range of acuity. In patients with either preoperative distance or near acuity of worse than 20/80, 40% and 48% of patients, respectively, improved to 20/80 or better. Postoperative retinal detachment developed in 5 patients (8%), with the macula involved in 2 patients, and all retinas were reattached successfully.

CONCLUSIONS

Macular translocation with 360 degrees retinectomy with silicone oil tamponade is effective in significantly improving visual function in patients with neovascular AMD, as demonstrated by the improvement in distance and near acuity and reading speed at 12 months after surgery in these patients. Although this is a complex surgical intervention, patients with preoperative visual acuity of 20/80 or better at near or distance are highly likely to retain the 20/80 or better acuity at 12 months after surgery. Macular translocation with 360 degrees retinectomy is an effective treatment option for patients with vision loss in their second eye resulting from neovascular AMD.

massive peripapillary subretinal neovascularization: an indication for submacular surgery

PURPOSE

To describe the course and outcome of three consecutive patients with massive peripapillary subretinal neovascularization secondary to ocular histoplasmosis syndrome managed with submacular surgery.

METHODS

Three eyes of three consecutive patients with progressive and massive peripapillary subretinal neovascularization secondary to ocular histoplasmosis syndrome were treated with submacular surgery and followed up for a mean of 41 months (range, 11-59 months). The main outcomes were surgical complications, visual acuity, and subretinal membrane recurrence.

RESULTS

Visual acuity improved in each patient from counting fingers, 20/25, and 20/400 preoperatively to 20/50, 20/20, and 20/20, respectively, at the last follow-up visit. With respect to complications, Patient 3 was found to have an operculated retinal tear approximately 1 month postoperatively, which was successfully treated with argon laser retinopexy. There were no cases of visually significant cataract, rhegmatogenous retinal detachment, or recurrent choroidal neovascularization in any of the operated eyes during the period of follow-up.

CONCLUSIONS

Submacular surgery proved safe and beneficial in this small series of young patients with massive peripapillary subretinal neovascularization secondary to ocular histoplasmosis syndrome and should be considered in this relatively uncommon clinical presentation.

Morphologic and angiographic assessment of the macula after macular translocation surgery with 360 degrees retinotomy

PURPOSE

To compare the optical coherence tomographic assessment of retinal thickness and the fluorescein angiographic appearance after macular translocation surgery for subfoveal choroidal neovascularization.

DESIGN

Retrospective, noncomparative, interventional case series.

PARTICIPANTS

Twenty-three consecutive eyes.

INTERVENTION AND TESTING

Optical coherence tomography and fluorescein angiography were performed before and 6 to 15 months (mean +/- standard error [SE], 10.4+/-0.7) after macular translocation surgery with a 360 degrees retinotomy in 23 patients, ages 48 to 79 years, with age-related macular degeneration (12 eyes), polypoidal choroidal vasculopathy (2 eyes), and high myopia (9 eyes). The diameter of the choroidal neovascularizations ranged from 0.3 to 2.6 disc diameters (mean +/- SE, 1.2+/-0.2), and the angle of rotation of the retina ranged from 11 degrees to 45 degrees (mean +/- SE, 29.1+/-2.1 degrees ).

RESULTS

The preoperative best-corrected visual acuity ranged from hand motions to 20/100, and the postoperative best-corrected visual acuity ranged from 20/667 to 20/25. Optical coherence tomography demonstrated a concave foveal configuration after surgery in all 23 eyes, with a mean foveal thickness of 150+/-11 micro m (mean +/- SE). Fluorescein angiography showed various degrees of fluorescein leakage with a pattern similar to cystoid macular edema in 16 of 23 eyes (70%).

CONCLUSIONS

The newly located macula after macular translocation surgery with a 360 degrees retinotomy had cystoid macular edema on fluorescein angiography and normal macular configuration with normal thickness in optical coherence tomography.

Macular translocation surgery with 360-degree peripheral retinectomy following ocular photodynamic therapy of choroidal neovascularization

PURPOSE

To determine the visual outcomes of eyes that underwent macular translocation surgery with 360 degrees peripheral retinectomy and silicone oil tamponade (MTS360) following ocular photodynamic therapy (OPT) with verteporfin for subfoveal choroidal neovascularization (CNV) associated with age-related macular degeneration (ARMD).

DESIGN

Observational case series.

METHODS

A retrospective review of patients who underwent MTS360 with silicone oil tamponade from August 5, 1998 through December 1, 2002. Patients who had at least one episode of OPT with verteporfin before surgery were identified. The number of OPT session, best-corrected Early Treatment Diabetic Retinopathy Study (ETDRS) visual acuity, complications (including postoperative CNV, retinal detachment [RD]), the presence or absence of cystoid macular edema (CME) by optical coherence tomography (OCT) were recorded.

RESULTS

Eight eyes of eight patients were identified that fulfilled the inclusion criteria. All eyes had at least one episode of OPT (mean, 1.5 treatments). All of these patients at the time of MTS360 demonstrated continued visual loss following the most recent OPT session. The mean preoperative visual acuity was 56 letters. Four of the eight eyes demonstrated CME by OCT on preoperative examination. There were no significant postoperative complications other than one eye that had a successful repair of an RD. At 3 months, the mean visual acuity was 54 letters. At last follow-up (mean, 10 months), the mean visual acuity was 61 letters (P =.5). The final mean visual acuity change for the patients who had only one prior OPT (five eyes) was +10 letters. The mean final visual acuity change for the patients who had multiple OPT sessions (three eyes) was -1 letter. Three of the four eyes that had preoperative CME continued to demonstrate CME at last follow-up. Two eyes that had concurrent cataract extraction surgery with MTS360 did not develop CME. No eyes developed a recurrent CNV during the postoperative period.

CONCLUSIONS

MTS360 with silicone oil tamponade for CNV associated with ARMD appears to be a viable option for patients who are continuing to lose vision in their better seeing eye following OPT with verteporfin. MTS360 appears to be effective in stabilizing vision, especially in patients who had previously undergone only one OPT session. Further studies are indicated to evaluate the efficacy of MTS360 in this current era of OPT.

Limited macular translocation for subfoveal choroidal neovascularization in age-related macular degeneration

PURPOSE

To examine the safety and efficacy of limited macular translocation followed by laser photocoagulation in the management of subfoveal choroidal neovascularization (CNV) in age-related macular degeneration (AMD).

METHODS

A prospective study was conducted on eight consecutive patients undergoing limited macular translocation followed by laser photocoagulation for the treatment of subfoveal classic CNV form of AMD. Patients were followed up for a minimum of 12 months. The magnitude of foveal translocation, visual outcomes and complications were assessed.

RESULTS

In all cases the fovea was successfully translocated inferiorly, with a median displacement of 1.1 mm. Thermal laser photocoagulation was subsequently performed in all cases. Visual acuity improved in five eyes, remained unchanged in two eyes and worsened in one eye. The mean improvement in visual acuity was by 0.19 logMAR. At 12 months, six of the eight patients (75%) achieved Snellen visual acuity of at least 6/15, with four patients (50%) achieving Snellen visual acuity of 6/9.

CONCLUSION

In this small case series, limited macular translocation was found to be an effective and reproducible means of treating small well-defined subfoveal CNV.

Retinal pigment epithelium translocation after choroidal neovascular membrane removal in age-related macular degeneration

PURPOSE

To test the feasibility of a new surgical technique and to assess visual function over the translocated retinal pigment epithelium (RPE) cells in patients operated on for subfoveal choroidal neovascularization (CNV) secondary to age-related macular degeneration (ARMD).

DESIGN

Retrospective, noncomparative, interventional case series.

PARTICIPANTS

Nine patients with previously untreated exudative ARMD underwent surgical excision of the subfoveal CNV with RPE translocation and were observed for 12 to 32 months.

METHODS

The surgery consisted of a standard three-port pars plana vitrectomy, excision of the CNV, and RPE translocation. Pre- and postoperative ocular examination included best-corrected visual acuity measurement, fundus color stereo photography, and fundus fluorescein angiography. Optical coherence tomography and confocal laser scanning ophthalmoscopy (cLSO) were performed after surgery. A crossfixation target and a single-point flashing light were projected on different areas of the posterior pole using a cLSO. Photopic 10 to 2 perimetry, photopic fine matrix mapping, and cLSO microperimetry were also performed after surgery in six patients.

MAIN OUTCOME MEASURES

Optical coherence tomography cross-sectional scans and cLSO RPE autofluorescence were recorded to detect the presence of viable translocated RPE. Visual acuity, fixation, photopic 10 to 2 perimetry, photopic fine matrix mapping, and cLSO microperimetry were used to test central visual function.

RESULTS

Retinal pigment epithelium was translocated successfully at the time of CNV removal from the edge of the RPE defect to a subfoveal location in seven of nine patients. One patient experienced proliferative vitreoretinopathy, but significant hemorrhage was not a feature. Optical coherence tomography showed the translocated RPE as an area of increased optical reflectivity with optical shadowing external to it. Confocal laser scanning ophthalmoscopy showed autofluorescence of the translocated RPE. The crossfixation target was seen when projected on the translocated RPE. During eccentric fixation, the patients could see a flashing point-target projected on the translocated RPE. Photopic 10 to 2 perimetry, photopic fine-matrix mapping, and cLSO microperimetry showed the presence of central visual function.

CONCLUSIONS

The authors propose that translocation of RPE at the time of CNV removal, from the edge of the RPE defect to a subfoveal location, may have a role in the surgical management of ARMD.

Age-related macular degeneration: epidemiology and optimal treatment

Age-related macular degeneration (AMD) is a common macular disease affecting elderly people in the Western world. It is characterised by the appearance of drusen in the macula, accompanied by choroidal neovascularisation (CNV) or geographic atrophy. The disease is more common in Caucasian individuals than in pigmented races. In predominantly Caucasian populations, the age-standardised prevalence of AMD in at least one eye is 7760 cases per million. The age-standardised cumulated 1-year incidence of AMD in at least one eye is 1051 cases per million individuals. AMD is the most important single cause of blindness among Caucasian individuals in developed countries. Blindness resulting from AMD rarely occurs before age 70, and most cases occur after age 80. The age-standardised 1-year incidence of legal blindness resulting from AMD is 212 cases per million. Two-thirds of AMD cases have CNV (exudative cases); the remainder has only geographic atrophy. In cross-sectional population-based studies about 45% of eyes with AMD have visual acuity reduced to 20/200 or worse. This is true both for exudative AMD and pure geographic atrophy. Age and genetic predisposition are known risk factors for AMD. Smoking is probably also a risk factor. Preventive strategies using macular laser photocoagulation are under investigation, but their efficacy in preventing visual loss is as yet unproven. There is no treatment with proven efficacy for geographic atrophy. Optimal treatment for exudative AMD requires a fluorescein angiographic study and a physician capable of interpreting it. For CNV not involving the foveal centre, the only evidence-based treatment is laser photocoagulation. For AMD cases with subfoveal CNV, good visual acuity, and predominantly classic fluorescence pattern on fluorescein angiography, photodynamic therapy with verteporfin is the treatment of choice. Photodynamic therapy is also effective in eyes with pure occult CNV and evidence of recent disease progression. For new subfoveal CNV with poor vision and recurrent CNV, laser photocoagulation can be considered.

Macular translocation with 360-degree peripheral retinectomy impact of technique and surgical experience on visual outcomes

PURPOSE

To evaluate the impact of technique and surgical experience on complications and outcomes of macular translocation surgery with 360-degree peripheral retinectomy (MTS360).

METHODS

Twenty-six consecutive patients underwent MTS360 in a prospective study of macular translocation surgery for subfoveal choroidal neovascularization (CNV) in eyes with age-related macular degeneration (ARMD). Data gathered included intraoperative and postoperative events and pre- and postoperative standardized visual acuity recorded as number of letters read. Because the surgical technique changed particularly during the first 16 cases, patients were grouped into an evolving treatment group of the first 16 patients (Group 1) and a modified treatment group of the final 10 patients (Group 2).

RESULTS

As techniques evolved in this series, ease of surgery increased. There were significant decreases in surgery duration and in number of retinotomies required to induce artificial retinal detachment. Number of postoperative retinal detachments decreased from five in Group 1 to none in Group 2. Change in visual acuity was significantly different between the two groups: Group 1 had an average loss of 14 letters (<3 lines) and Group 2 an average gain of 3 letters (<1 line) (P < 0.05). Average postoperative visual acuity was significantly better for Group 2 (68 letters, approximately 20/80) than for Group 1 (47 letters, approximately 20/250) (P < 0.01).

CONCLUSION

Surgical experience and a progressively modified surgical technique decreased perioperative complications and improved visual outcomes after MTS360. With modified MTS360, central vision has been salvaged for almost 1 year of follow-up in patients presenting with vision loss from subfoveal CNV and ARMD.

Macular translocation: unifying concepts, terminology, and classification

PURPOSE

To describe some unifying concepts, terminology, and classification of macular translocation so as to facilitate communication within the scientific community.

METHODS

A panel of ophthalmologists with expertise in macular translocation reviewed available data and developed some unifying concepts, terminology, and classification of macular translocation.

RESULTS

Macular translocation may be defined as any surgery that has a primary goal of relocating the central neurosensory retina or fovea intraoperatively or postoperatively specifically for the management of macular disease. It may be classified according to the size of the retinotomy and, where applicable, the technique of chorioscleral shortening used. The direction of macular translocation is denoted by the movement of the neurosensory macula relative to the underlying tissues. Effective macular translocation may be defined as successful intraoperative or postoperative relocation of the fovea overlying a subfoveal lesion to an area outside the border of the lesion. The concepts of minimum desired translocation and median postoperative foveal displacement can give some useful idea of the likelihood of effective macular translocation before surgery.

CONCLUSIONS

Use of a common standardized terminology for macular translocation will facilitate communication within the scientific community and enhance further research in this area. However, the definitions, terms, classification, and concepts concerning macular translocation are likely to continue to evolve as macular translocation undergoes further modifications and refinements.

Initial experience of inferior limited macular translocation for subfoveal choroidal neovascularization resulting from causes other than age-related macular degeneration

PURPOSE

To report our initial experience of inferior limited macular translocation in patients with subfoveal choroidal neovascularization resulting from causes other than age-related macular degeneration.

METHODS

We conducted a retrospective study of 23 eyes of 22 patients with choroidal neovascularization involving the foveal center secondary to pathologic myopia (11 eyes), ocular histoplasmosis syndrome (four eyes), angioid streaks (four eyes), idiopathic neovascularization (three eyes), and multifocal choroiditis (one eye), in which the fovea was moved inferiorly by means of limited macular translocation surgery. The mean preoperative best-corrected visual acuity was 20/150, and in five of 23 eyes (21.7%) the visual acuity was 20/80 or better. The major outcome measures were preoperative and postoperative visual acuity, postoperative foveal displacement, and complications related to the surgery.

RESULTS

The mean postoperative follow-up was 10.82 months (range, 6 to 18 months). Postoperative best-corrected visual acuity improved by 2 or more Snellen lines of visual acuity in 11 of 23 eyes (47.82%), remained within 1 line in seven of 23 eyes (30.43%), and worsened 2 or more lines of vision in five of 23 eyes (21.74%). The mean postoperative best-corrected visual acuity was 20/100, and in 12 of the 23 eyes (52.17%) the visual acuity achieved was 20/80 or better. Retinal detachment was the most frequent complication and occurred in six eyes (26%).

CONCLUSIONS

Our initial experience with limited macular translocation shows that this treatment modality offers the potential to improve visual function in some eyes with subfoveal choroidal neovascularization secondary to myopia, ocular histoplasmosis syndrome, angioid streaks, idiopathic neovascularization, and multifocal choroiditis. Although longer and more complete follow-up is needed, the results of this initial series warrant further studies to define the precise role of macular translocation in the management of these conditions.

Complications associated with limited macular translocation

PURPOSE

To report the ocular complications associated with the limited macular translocation procedure.

METHODS

Retrospective review of 153 consecutive eyes of 151 patients that had the limited macular translocation procedure for subfoveal choroidal neovascularization between April 1996 and February 1999. The major study variables investigated included the incidence of specific ocular complications and their impact on visual acuity at 3 months after the surgery. In addition, baseline patient characteristics and operative factors were evaluated to determine whether they were significant risk factors for the development of an ocular complication. The existence of a surgical procedure learning process was investigated.

RESULTS

One hundred forty-one (92.15%) of 153 eyes achieved at least 3-month follow-up. At least one complication occurred in 53 of 153 eyes (34.6%) and in 51 of these 53 eyes (96. 22%) the complications occurred before 3 months of postoperative follow-up. The intraoperative and postoperative complications included retinal detachment (17.4%), retinal breaks (13.4%), macular holes (7.8%), macular fold (4.6%), and intraocular hemorrhage (vitreous, subretinal, or choroidal; 9.2%). Eyes that developed retinal detachment, subretinal hemorrhage, and macular fold had significantly more loss of visual acuity than eyes without each of these complications (P =.0001, P =.038, and P =.027, respectively). The presence of predominantly classic choroidal neovascularization, the occurrence of an intraoperative retinal break, any intraocular hemorrhage, or macular fold formation were significantly associated with retinal detachment (P =.021, P =.025, P =.013, and P =.014, respectively). The incidence of any complication, retinal detachment, and hemorrhage significantly decreased during the study period, suggesting a learning process (P =.03, P =.006, P =.027, respectively).

CONCLUSIONS

A variety of ocular complications can occur during or after limited macular translocation, and some are associated with reduced postoperative visual acuity. Improved surgical techniques and experience may significantly reduce the incidence of these complications.