Complications associated with limited macular translocation

Advances in the study of tissue-engineered retinal pigment epithelial cell sheets

Regarded as the most promising treatment modality for retinal degenerative diseases, retinal pigment epithelium cell replacement therapy holds significant potential. Common retinal degenerative diseases, including Age-related Macular Degeneration, are frequently characterized by damage to the unit comprising photoreceptors, retinal pigment epithelium, and Bruch's membrane. The selection of appropriate tissue engineering materials, in conjunction with retinal pigment epithelial cells, for graft preparation, can offer an effective treatment for retinal degenerative diseases. This article presents an overview of the research conducted on retinal pigment epithelial cell tissue engineering, outlining the challenges and future prospects.

Management of Choroidal Neovascularization Secondary to Pathological Myopia: The Era of Changes

Choroidal neovascularization (CNV) secondary to pathological myopia is an important cause of significant visual impairment in young adults. High myopia is particularly prevalent in Asian population. New scientific contributions have been made to the understanding of high myopia and myopic CNV. Treatment for myopic CNV has previously relied on photodynamic therapy, laser photocoagulation, and submacular surgery. The treatment outcomes from these modalities are, however, controversial. The introduction of antiangiogenic agents including bevacizumab and ranibizumab has brought the treatment of myopic CNV into a new era. The purpose of this review was to provide an overview of the natural history of myopic CNV, the prognostic factors, and the various treatment options including laser photocoagulation and photodynamic therapy, with particular attention on antiangiogenic agents.

[Intravitreal ranibizumab injection for the treatment of idiopathic choroidal neovascularisation in young patients]

PURPOSE

To evaluate the safety and efficacy of intravitreal injection of ranibizumab 0.5mg in the treatment of idiopathic choroidal neovascularisation in young patients, which is the second most common cause of macular CNV in patients under 50 years of age.

PATIENTS AND METHODS

This single-center, prospective, interventional, uncontrolled, nonrandomized clinical case series study included 13 eyes of 13 consecutive young patients with idiopathic macular choroidal neovascularisation treated with monthly intravitreal injections of 0.5mg ranibizumab. Prior to treatment, measurement of best-corrected visual acuity (BCVA), fundus examination, fluorescein angiography (FA) and macular optical coherence tomography (OCT) were performed. Measurement of visual acuity, fundus exam and OCT were repeated each month. A repeated monthly injection was performed in the event of persistence or recurrence of neovascular activity.

RESULTS

Ten women and three men, mean age 34±7.88 years at time of diagnosis, were included in the study. Mean best-corrected visual acuity improved dramatically throughout the study, going from 0.74 LogMar at enrolment to 0.45 LogMar at 13 months (P<10(-6)). On average, two intravitreal injections of ranibizumab (0.5 mg) were required during this year. Mean follow-up was 13±7.6 months.

DISCUSSION

Management of idiopathic CNV in young patients is difficult, due to frequent recurrences despite treatment. Argon laser photocoagulation, photodynamic therapy, and subretinal surgery offer limited results in terms of visual recovery and recurrence.

CONCLUSION

Intravitreal ranibizumab injection appears to be safe and effective for treatment of idiopathic macular CNV in young patients. A longer-term prospective trial is required to corroborate these results.

Treatment of polypoidal choroidal vasculopathy with photodynamic therapy. 2002

PURPOSE

To study the effects of photodynamic therapy using verteporfin in the treatment of patients with subfoveal polypoidal choroidal vasculopathy (PCV).

METHODS

A retrospective chart review of 16 consecutive patients with subfoveal PCV treated with photodynamic therapy using verteporfin was performed.

RESULTS

The mean age of the patients involved was 70.5 years. The mean follow-up time was 12 months. The visual acuity improved in 9 (56.3 %), remained the same in 5 (31.3 %), and decreased in 2 (12.5 %). The mean change in visual acuity was an improvement of 2.38 lines, a difference that was highly significant (P = 0.004). The change in visual acuity was negatively correlated with increasing age. The final visual acuity was positively correlated with initial acuity and negatively correlated with age. These results were confirmed by multiple linear regression. No patient had any lasting complication from the treatment.

CONCLUSIONS

Subfoveal PCV has no proven method of treatment. Although the follow-up time and the number of patients in this pilot study were limited, the encouraging results and lack of complications suggest that further study is indicated.

Macular hole secondary to a subretinal hemorrhage

PURPOSE

To report a case of a full-thickness macular hole developing after a subretinal hemorrhage in a patient with age-related macular degeneration (AMD).

METHODS AND PATIENTS

A 75-year-old woman was followed with sequential fluorescein angiography and optical coherence tomography from her initial presentation to postoperative follow-up.

RESULTS

The patient presented with sudden visual loss in her left eye. Fluorescein angiography showed AMD with a significant subretinal hemorrhage. Five months later, the visual acuity of her left eye had further deteriorated and examination revealed that a full-thickness macular hole had developed. Surgical treatment achieved complete anatomic closure of the macular hole with significant improvement in the visual acuity of the affected eye.

CONCLUSIONS

A full-thickness macular hole may rarely develop following a subretinal hemorrhage. In such cases, surgical closure can improve the functional outcome.

Macular translocation for neovascular age-related macular degeneration

BACKGROUND

Macular translocation has been proposed by vitreoretinal surgeons to displace the neuroretinal tissue onto healthy retinal pigment epithelium and choroid when the macula has been invaded by subretinal neovascularisation.

OBJECTIVES

This review aims at assessing the effectiveness of macular translocation for preserving or improving vision in patients with neovascular age-related macular degeneration (AMD).

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) in The Cochrane Library, MEDLINE, EMBASE and Caribbean Literature on Health Sciences (LILACS). There were no language or date restrictions in the search for trials.The electronic databases were last searched on 21 July 2008.

SELECTION CRITERIA

We included randomised or quasi randomised controlled trials comparing macular translocation with any other treatment or observation.

DATA COLLECTION AND ANALYSIS

Two authors independently extracted the data. The risk ratio (RR) of visual loss and visual gain was estimated at one year after treatment.

MAIN RESULTS

Only one small unblinded study on 50 people compared full macular translocation with photodynamic therapy (PDT) in AMD patients with predominantly classic subfoveal choroidal neovascularisation (CNV). At the last examination, performed in most of the cases after one year, there was no difference in the rate of visual loss of 3 or more lines (translocation versus PDT: RR 0.56, 95% confidence interval (CI) 0.22 to 1.43), as well as in the mean change of contrast sensitivity (1 letter favouring translocation; 95% CI -3.51 to 5.51) and the rate of recurrence of CNV (translocation versus PDT: RR 1.56, 95% CI 0.83 to 2.91). Other outcomes significantly favoured translocation, such as the gain of 3 or more ETDRS lines (RR 21, 95% CI 1.30 to 340.02), the mean change of visual acuity (mean difference (MD) 14.60, 95% CI 5.39 to 23.81) and the mean change of near visual acuity score (MD 17.80, 95% CI 3.98 to 31.62) which is obtained with an algorithm. Serious complications reported after macular translocation were retinal detachment in 6/25 patients and diplopia requiring prismatic correction in 5/25 patients.

AUTHORS' CONCLUSIONS

There is insufficient evidence from randomised controlled trials on the effectiveness of macular translocation, which is also not free of important risks. Furthermore, this technique is difficult to perform and a long surgical training is required. Future studies might include patients with small neovascular lesions that failed to respond to current pharmacological therapies and are willing to accept the risks associated with surgery to try to improve visual acuity.

SELECTIVE PHOTODYNAMIC THERAPY FOR NEOVASCULAR AGE-RELATED MACULAR DEGENERATION WITH POLYPOIDAL CHOROIDAL NEOVASCULARIZATION

PURPOSE

To evaluate the efficacy of selective treatment with indocyanine green (ICG) angiography-guided photodynamic therapy (PDT) with verteporfin for polypoidal choroidal vasculopathy (PCV).

METHODS

In this retrospective consecutive series, 30 eyes of 30 patients with PCV were included. Complete ocular examination, digital fluorescein angiography (FA), ICG angiography, and optical coherence tomography were performed at baseline and at standard intervals thereafter. ICG angiography-guided PDT was performed on all eyes. Only the area of the active PCV or "hot spot" evident on the ICG angiogram was treated. A spot size was chosen to cover the active neovascular lesion with a 200-mum border. Retreatment was performed when angiography revealed a recurrent lesion.

RESULTS

Thirty eyes with PCV were treated and followed for 1 year. Mean age of the patients was 75 years (range, 55-90 years). These patients were all classified as having occult choroidal neovascularization (CNV) with FA and polypoidal CNV with ICG angiography. Improvement of vision (>or=3 lines) was achieved in 15 eyes (50%). Nine eyes had stable vision (30%), and 6 eyes (20%) had a decrease in vision (>or=3 lines). Repeated treatment was required in 15 eyes (50%) for an average of 2.2 treatments in 1 year.

CONCLUSION

This study indicates that stabilization or improvement of vision is achieved in most eyes (80%) with neovascular AMD from PCV after selected ICG angiography-guided PDT. These outcomes compare very favorably with those in previous reports on the treatment of occult CNV. Reduced collateral damage to the choriocapillaris and reduced upregulation of vascular endothelial growth factor are presumed to be the explanation for this apparently better outcome. Further studies with longer follow-up are warranted to investigate the long-term efficacy in these conditions.

Photodynamic therapy vs limited macular translocation in the management of subfoveal choroidal neovascularization in pathologic myopia: a two-year study

PURPOSE

To compare the results of limited macular translocation and photodynamic therapy (PDT) in subfoveal choroidal neovascularization (CNV) attributable to pathologic myopia with a 24-month follow-up.

DESIGN

Retrospective analysis of nonrandomized interventional clinical study.

METHODS

Retrospective review of 66 consecutive patients: 34 myopic eyes with subfoveal neovascularization treated by PDT and 32 operated on with the translocation technique. Translocation was considered principally when the lesion size was adequate (nasal inferior margin of the membrane less than half a disk diameter away from the center of the fovea) with duration of symptoms of less than four months. Main outcome measure was the postoperative change in visual acuity.

RESULTS

In the translocation group, mean gain in visual acuity was greater than in the PDT group (+2.8 lines and -1.8 line, respectively, P = .001). In the translocation group, 55% of eyes gained 3 lines or more at two years compared with 10% in the PDT group. Sixty percent of eyes in the translocation group vs 40% in the PDT group had an improvement of at least five letters. Mean foveal displacement after translocation was 906 mum; postoperative complications included retinal detachment (three eyes), macular fold (one eye), and transient diplopia (four eyes). In young patients, the postoperative gain was better in both groups. In the translocation group, mean survival time for choroidal neovascularization recurrence was 40 months for patients younger than 40 years and 20 months for older patients.

CONCLUSIONS

Translocation showed better results than PDT at two years. Further studies are required to confirm these findings.

Étude rétrospective comparant la translocation maculaire limitée et la photothérapie dynamique dans la néovascularisation choroïdienne rétrofovéale de la myopie forte

PURPOSE

To analyze the results of limited macular translocation (MT) and photodynamic therapy (PDT) in subfoveal choroidal neovascularization due to degenerative myopia, with a minimum follow-up of 12 months.

METHODS

Retrospective review of 55 consecutive patients: 31 eyes were treated using PDT and 24 were operated on with the limited macular translocation technique with chorioscleral infolding described by de Juan. Before and after each treatment, a complete examination comprised visual acuity, fundus examination, fluorescein angiography, and optical coherence tomography. Mean follow-up was 14 months in the PDT group and 19 months in the MT group.

RESULTS

The improvement in visual acuity was better in the MT group than in the PDT group and was correlated with younger age (p<0.001). At month 12, visual acuity improved by 3 ETDRS lines or more in 6 six eyes of the PDT group (19%), with no improvement over 6 lines. In the MT group, visual acuity improved by 3 lines in 14 eyes (58%) including 8 eight eyes (33%) with an improvement of 6 lines or more. Final visual acuity remain unchanged (+/-2 lines) in 16 eyes of the PDT group (66%) and 8 eight eyes of the MT group (33%), and decreased in 9 nine eyes in the PDT group (29%) versus 2 two eyes in the MT group (8%). Mean gain in visual acuity at 12 months was +3.5 ETDRS lines in the MT group and -0.1 line in the PDT group (p=0.001). The mean displacement of the fovea after translocation was 950 microm. The mMean number of PDT treatments was 2.3 during the 12-month follow-up.

CONCLUSIONS

Limited macular translocation allowed provided a significant improvement in visual acuity in some eyes with subfoveal neovascularization in myopia, especially in young patients, and resulted in a moderate rate of complications. Longer follow-up and further controlled and randomized studies are required to confirm these encouraging findings.

Emerging biological therapies for age-related macula degeneration

Age-related macular degeneration (AMD) has emerged as the dominant cause of irretrievable visual loss in most developed countries achieving increasing longevity. The major cause of rapid and severe visual loss is the development of choroidal neovascularisation under the macula (exudative or wet AMD). Physical treatments, especially thermal laser and photodynamic therapy following intravenous verteporfin, have made statistically significant but modest progress in limiting visual loss, whereas surgical translocation of the macula and even light or electrically sensitive retinal implants are spectacular, but likely to only ever benefit a few. Intravitreal fine needle injections and slow release implants of steroid derivatives have opened new areas for investigation. The blocking of endothelial receptors for vascular endothelial growth factor by RNA-based aptamer or immune-protected antibody fragments has been the subject of intensive scientific development and large scale clinical trials. This approach may expand the range of AMD patients amenable to treatment. Additional therapeutic gains await measures to modify photoreceptor cell loss and subretinal fibrosis involving the retinal pigment epithelium as well as prevention or treatment for pigment epithelial detachment. Epidemiological associations with smoking and diet, and antioxidant dietary supplements offer important strategies for prevention.

Choroidal neovascularisation in pathological myopia: an update in management

Choroidal neovascularisation (CNV) secondary to pathological myopia is an important cause of significant visual impairment in young and middle aged adults globally and is particularly prevalent in Asian populations. In the past few years, there have been rapid advancements in the different treatments for myopic CNV. The purpose of this perspective is to give an overview of the natural history of myopic CNV and the various treatment options including laser photocoagulation, photodynamic therapy, sub-macular surgery, and macular translocation surgery. Future directions in the management of myopic CNV are also discussed.

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.

Two-year results of macular translocation with scleral infolding in myopic choroidal neovascularisation

PURPOSE

To assess the two year outcome following macular translocation (MT) with scleral infolding in the management of myopic subfoveal choroidal neovascularisation (CNV).

DESIGN

Prospective, clinical interventional noncomparative consecutive case series.

PARTICIPANTS

79 eyes of 79 patients with myopic subfoveal CNV and less than 6 months of duration of the symptoms.

INTERVENTION

MT with scleral infolding.

MAIN OUTCOME MEASURES

Visual Acuity (VA), reading ability of 12 point Arial letter sentences at a reading distance without magnifying systems and foveal displacement.

RESULTS

Mean preoperative VA was 20/125, after two years the mean VA was 20/80. Reading ability of 12 point Arial letter sentences at a reading distance (33 cm) was obtained in 59% of the eyes at one year, descending to 43% at two years. Mean foveal displacement after surgery was 942 microns. Intraoperative complications have been: retinal breaks (21.5%) and choroidal haemorrhage not affecting the posterior pole (3.7%). Main postoperative complications have been: Insufficient foveal displacement: 20%; Retinal detachment: 8.8%; Subfoveal recurrence: 28%; macular fold: 2.5% and macular hole: 1.2%.

CONCLUSION

MT with scleral infolding offers the opportunity to recover central vision and reading ability in patients with myopic CNV but it remains unpredictable.

Result of Photodynamic Therapy for Idiopathic Subfoveal Choroidal Neovascularization

PURPOSE

To investigate the factors that affect final vision following photodynamic therapy (PDT) for idiopathic subfoveal choroidal neovascularization (CNV).

METHODS

A retrospective review of 16 patients whose eyes were diagnosed as idiopathic subfoveal CNV and were followed up for a minimum of 9 months. Statistical analysis was performed to investigate relationships between sex, age, size of the lesion, and initial vision compared to final vision.

RESULTS

In the PDT group (10 eyes), the mean age of the patients was 34 years, mean size of the lesion was 1300 microm, mean initial vision was 20/60, and 7 of the 10 patients (70%) showed more than a two-line improvement in vision. Factors affecting final vision were sex (p=0.049), initial vision (p=0.0455), and size of the lesion (p=0.006). In the observation group (6 eyes), the mean age of the patients was 39 years, mean size of the lesion was 575 microm, mean initial vision was 20/32, and 5 of the 6 patients (83%) showed more than a two-line improvement in vision.

CONCLUSIONS

The prognosis of idiopathic CNV was favorable as was reported in other studies. In the PDT group, statistically significant factors affecting final vision were initial vision, size of the lesion, and sex. However, since the number of patients sampled was insufficient and the average size of the lesions in the female patients was smaller, the size of the lesion seems to be the most important factor.

Macular translocation in patients with recurrent subfoveal choroidal neovascularization after laser photocoagulation for nonsubfoveal choroidal neovascularization

PURPOSE

To report visual outcomes and to examine surgical factors affecting outcomes in patients undergoing macular translocation for recurrent subfoveal choroidal neovascularization after laser photocoagulation for nonsubfoveal choroidal neovascularization.

DESIGN

Retrospective, noncomparative, interventional case series.

PARTICIPANTS

A consecutive series of 31 eyes of 29 patients who underwent macular translocation for recurrent subfoveal choroidal neovascularization after laser photocoagulation for nonsubfoveal choroidal neovascularization.

INTERVENTION

Inferior macular translocation with punctate retinotomy performed by a single surgeon.

OUTCOME MEASURES

Surgical and visual outcomes at 3 and 6 months after surgery and complications data are reported. Associations between surgical factors and visual outcomes were analyzed statistically.

RESULTS

Effective translocation was achieved in 77.4% of eyes. At 6 months, 54% of eyes achieved visual acuity (VA) better than 20/100, and 46% of eyes gained the equivalent of > or =2 Early Treatment Diabetic Retinopathy Study lines of vision. No association between size of recurrent choroidal neovascularization and visual outcome was identified. Eyes with a larger scar size experienced lower VA at 3 and 6 months, but scar size was not associated with change in VA at 3 and 6 months. Subretinal dissection during surgery to detach the macula was required in 8 of 31 eyes and was associated with a significantly increased incidence of peripheral retinal breaks. However, there was no difference in either VA or change in VA in eyes with and without subretinal dissection. Retinal detachment (RD) occurred in 6 of 31 eyes. No significant difference in the RD rate was observed between groups with or without subretinal dissection (P = 0.30).

CONCLUSION

Our pilot data suggest that macular translocation can result in favorable surgical outcomes in patients with recurrent subfoveal choroidal neovascularization after laser photocoagulation for nonsubfoveal choroidal neovascularization. Use of subretinal dissection intraoperatively in these patients does not seem to affect visual outcome adversely, but may be associated with increased risk of peripheral retinal breaks.

Polypoidal choroidal vasculopathy

Polypoidal choroidal vasculopathy was first described as a peculiar hemorrhagic disorder of the macula, characterized by recurrent sub-retinal and sub-retinal pigment epithelium bleeding in middle aged black women. The use of indocyanine green angiography and subsequently of optical coherent tomography has widened our ability to study and understand the pathophysiology of this disorder. The primary abnormality involves the choroidal circulation, and the characteristic lesion is an inner choroidal vascular network of vessels ending in an aneurysmal bulge or outward projection, visible clinically as a reddish orange, spheroid, polyp-like structure. We have also recognized that individuals of African-American and Asian descents are more at risk for developing polypoidal choroidal vasculopathy as the disorder seems to preferentially affect pigmented individuals. However, it has been shown that while that still holds true, patients of other racial backgrounds may be afflicted. Particularly, polypoidal choroidal vasculopathy has been found to be present in about 8-13% of white patients with clinical appearance of exudative age-related macular degeneration. Polypoidal choroidal vasculopathy has also been reported in Irish, French, German, and Italian patients. The natural course of the disease often follows a remitting-relapsing course, and clinically, it is associated with chronic, multiple, recurrent serosanguineous detachments of the retinal pigment epithelium and neurosensory retina with long-term preservation of good vision. Photodynamic treatment appears to be a promising alternative to conventional laser therapy, for the treatment of polypoidal choroidal vasculopathy. In conclusion, polypoidal choroidal vasculopathy seems to be a distinct clinical entity that should be differentiated from other types of choroidal neovascularization associated with age-related macular degeneration and other known choroidal degenerative, inflammatory, and ischemic disorders.

Photodynamic therapy with verteporfin for subfoveal idiopathic choroidal neovascularization

OBJECTIVE

To study the safety and efficacy of photodynamic therapy (PDT) with verteporfin in treating subfoveal choroidal neovascularization (CNV) of idiopathic cause.

DESIGN

A prospective, noncomparative, consecutive, open-label, two-center, interventional case series.

PARTICIPANTS

Patients aged 50 years or younger with the diagnosis of idiopathic CNV by exclusion of other related causes together with the CNV extending under the geometric center of the foveal avascular zone.

METHODS

Seventeen eyes from 17 patients received PDT with verteporfin according to a standardized protocol. Retreatment was considered if fluorescein leakage from the CNV was shown in fluorescein angiography at every 3-month follow-up. The visual, clinical, and angiographic responses were observed. Complications from treatment were monitored and documented.

MAIN OUTCOMES MEASURES

The changes in the best-corrected visual acuity (BCVA) at the 1-year follow-up. The proportion of patients with improved (gained 2 lines or more), stable, and dropped (lost 2 lines or more) vision and the mean number of treatments required during the 1-year interval were measured. Complications were monitored and tabulated.

RESULTS

Seventeen eyes with complete 1-year follow-up were analyzed. The mean logarithm of the minimum angle of resolution BCVA improved from 0.64 to 0.41 (Wilcoxon signed-ranks test, P = 0.007). Sixteen eyes (94%) had stable or improved vision. Only one patient (6%) had moderate loss of vision. The mean number of PDT treatment was 1.8 per eye over the 1-year period. Patients with smaller lesion size or active vascular CNV on presentation were more likely to have a final BCVA of 20/100 or better (Fisher's exact test, P = 0.006 and P = 0.015, respectively). No serious local or systemic complications were encountered.

CONCLUSIONS

PDT seems to be a promising treatment strategy in achieving a stable or improved vision for subfoveal idiopathic CNV. The treatment was well tolerated. Further studies and longer follow-up are warranted to assess the long-term safety and efficacy of PDT compared with observation or other treatment modalities.

Review Article. New treatments in age-related macular degeneration

Age-related macular degeneration (AMD) is the leading cause of legal blindness in individuals 50 years and older in the developed world. Choroidal neovascularization (CNV) in exudative AMD is responsible for the majority of severe vision loss. Until recently, laser photocoagulation was the only well-established and widely accepted treatment for CNV. However, it is beneficial only for a small subset of patients, has a high rate of CNV persistence and recurrence and results in iatrogenic, collateral damage to the overlying retina. These issues make it difficult to recommend in the case of subfoveal lesions. Consequently, numerous experimental therapeutic interventions are under investigation with the common objective of destroying the CNV but leaving the foveal neurosensory retina intact. Treatment modalities can be grouped into five major categories: photodynamic therapy; radiotherapy; transpupillary thermotherapy; anti-angiogenic and angiostatic agents; and surgical intervention. The present review aims to explain the rationale behind these new treatments, analyse the evidence for their safety and efficacy, determine their stage of development and indicate in which patients they are potentially useful.

Macular relocation after photodynamic therapy for recurrent choroidal neovascular membrane: visual results and histopathological findings

BACKGROUND/AIMS

The findings in a patient treated with photodynamic therapy (PDT) followed by macular relocation surgery (MRS) are presented.

METHODS

Histopathological evaluation of the choroidal neovascular membrane (CNV) specimen including immunohistochemical assessment.

RESULTS

Microscopy revealed one CNV area that was richly vascular with attached retinal pigment epithelial cell monolayer and another area that was made up of densely collagenous avascular tissue with adherent fragments of Bruch's membrane and glial elements.

CONCLUSION

The findings suggest that the PDT treated part of the CNV may have been adherent to the neuroretina and may have contributed to the formation of the macular hole. Caution is advised when considering MRS for CNV previously treated PDT.

Age-related macular degeneration: etiology, pathogenesis, and therapeutic strategies

Age-related macular degeneration is the principal cause of registered legal blindness among those aged over 65 in the United States, western Europe, Australia, and Japan. Despite intensive research, the precise etiology of molecular events that underlie age-related macular degeneration is poorly understood. However, investigations on parallel fronts are addressing this prevalent public health problem. Sophisticated biochemical and biophysical techniques have refined our understanding of the pathobiology of drusen, geographic atrophy, and retinal pigment epithelial detachments. Epidemiological identification of risk factors has facilitated an intelligent search for underlying mechanisms and fueled clinical investigation of behavior modification. Gene searches have not only brought us to the cusp of identifying the culpable gene loci in age-related macular degeneration, but also localized genes responsible for other macular dystrophies. Recent and ongoing investigations, often cued by tumor biology, have revealed an important role for various growth factors, particularly in the neovascular form of the condition. Transgenic and knockout studies have provided important mechanistic insights into the development of choroidal neovascularization, the principal cause of vision loss in age-related macular degeneration. This in turn has culminated in preclinical and clinical trials of directed molecular interventions.

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.

Macular translocation with 360 degree retinotomy for management of age-related macular degeneration with subfoveal choroidal neovascularization

PURPOSE

The aim of this study is to evaluate the functional outcome in a group of patients treated with full macular translocation (FMT) with 360-degree retinotomy for treatment of age-related macular degeneration (ARMD) with subfoveal choroidal neovascularization.

DESIGN

Consecutive interventional case series.

METHODS

Fifty consecutive eyes (50 patients) with ARMD and subfoveal neovascularization who underwent a FMT in our department from January 1999 to July 2000 are included in this study. Compensatory muscle surgery, as described by Eckardt and associates, was performed on all the eyes. The median follow-up is 21 months (range, 12 to 36; SD, 5.4).

RESULTS

The best-corrected postoperative visual acuity (BCVA) was improved by 2 or more Snellen lines in 33 eyes (66%) and remained stable (+/-1 line) in 14 eyes (28%). Only 3 eyes (6%) experienced a deterioration of the BCVA of 2 or more lines. The final BCVA was 20/50 or better in 32% of the cases; only 8 eyes (16%) had a final BCVA < 20/200. Thirty-four (68%) patients are able to read newspaper print (3.3/10) with normal (+3 diopters to +4 diopters) or increased (+5 diopters to +8 diopters) reading ads. Other patients are able to read with magnifying systems. Complications included proliferative vitreoretinopathy (PVR) in 9 eyes (18%), recurrent choroidal neovascularization in 5 eyes (10%), diplopia in 3 eyes (6%), choroidal hemorrhage in 2 eyes (4%), macular hole in 1 eye, and temporary hypotony in 1 eye.

CONCLUSIONS

As 68% of the patients in the study group regained reading vision with reading glasses, FMT can be considered an effective approach in cases of subfoveal choroidal neovascularization. Further investigations are necessary to determine which patients will have the most benefit from this complex therapeutic method.

Treatment of subfoveal choroidal neovascularization associated with multifocal choroiditis and panuveitis with photodynamic therapy

PURPOSE

To study the effects of photodynamic therapy (PDT) using verteporfin on the treatment of patients with subfoveal choroidal neovascularization (CNV) secondary to multifocal choroiditis and panuveitis (MCP), an uncommon disorder with no proven forms of therapy.

METHODS

A retrospective chart review of seven consecutive patients with subfoveal CNV secondary to MCP treated with PDT using verteporfin was performed.

RESULTS

The mean age of the 7 patients (all myopic women) was 41.4 years. A mean of 1.86 treatments was performed, and the mean follow-up time was 10 months. Four of the seven patients were treated unsuccessfully with corticosteroids before referral for PDT. The mean improvement of visual acuity was 0.86 line; 3 patients (42.8%) had an improvement in visual acuity representing at least a halving of their visual angle, while the other 4 patients remained stable. There were no treatment-related side effects.

CONCLUSIONS

Although the follow-up time and the number of patients in this study were limited, the use of PDT was associated with stabilization or improvement of visual acuity in patients with subfoveal CNV secondary to MCP. Further study of this treatment modality is indicated.

Treatment of polypoidal choroidal vasculopathy with photodynamic therapy

PURPOSE

To study the effects of photodynamic therapy using verteporfin in the treatment of patients with subfoveal polypoidal choroidal vasculopathy (PCV).

METHODS

A retrospective chart review of 16 consecutive patients with subfoveal PCV treated with photodynamic therapy using verteporfin was performed.

RESULTS

The mean age of the patients involved was 70.5 years. The mean follow-up time was 12 months. The visual acuity improved in 9 (56.3 %), remained the same in 5 (31.3 %), and decreased in 2 (12.5 %). The mean change in visual acuity was an improvement of 2.38 lines, a difference that was highly significant ( = 0.004). The change in visual acuity was negatively correlated with increasing age. The final visual acuity was positively correlated with initial acuity and negatively correlated with age. These results were confirmed by multiple linear regression. No patient had any lasting complication from the treatment.

CONCLUSIONS

Subfoveal PCV has no proven method of treatment. Although the follow-up time and the number of patients in this pilot study were limited, the encouraging results and lack of complications suggest that further study is indicated.

Inferior limited macular translocation for subfoveal choroidal neovascularization secondary to age-related macular degeneration: 1-year visual outcome and recurrence report

PURPOSE

To report the 1-year visual outcomes and incidence of persistent and recurrent choroidal neovascularization (CNV) after limited macular translocation (LMT) for subfoveal CNV in patients with age-related macular degeneration (ARMD).

DESIGN

Interventional case series.

METHODS

Retrospective review of 102 consecutive eyes of 101 patients that had the inferior limited macular translocation procedure for subfoveal choroidal neovascularization secondary to ARMD. The outcome measures were visual acuity at 12 months after surgery, change in visual acuity from baseline, the proportion of eyes with moderate (3 or more lines) or severe (6 or more lines) visual acuity loss, and cumulative incidence of persistent or recurrent CNV and its impact on visual acuity. Cumulative incidence was estimated using Kaplan-Meier survival analysis methods. Association between persistence and recurrence of CNV and the Snellen visual acuity recorded at each follow-up visit was evaluated using the Wilcoxon rank-sum test.

RESULTS

Eighty-six (84.3%) of 102 eyes completed the 1-year follow-up. By 12 months postoperatively, 35 (40.7%) of the 86 eyes achieved visual acuity of 20/100 or better while 34 (39.5%) of the 86 eyes experienced 2 or more Snellen lines of visual improvement. In the 52 eyes with effective translocation and complete laser photocoagulation of the CNV complex with sparing of the sensory fovea, the estimated incidence of recurrence was 34.6% at 12 months (95% confidence interval of 21%-48%). Sixty-five percent of the recurrences were subfoveal and caused a decrease in visual acuity. There was a trend toward worse median change in visual acuity in eyes with persistent or recurrent CNV.

CONCLUSIONS

Limited macular translocation for the treatment of subfoveal CNV secondary to ARMD is associated with improvement in visual acuity in approximately 39.5% of eyes and enables complete laser photocoagulation of the neovascular complex with sparing of the sensory macula in approximately 60.4% of eyes that complete 1 year follow-up. Persistence and recurrence of CNV are common after LMT and are important causes of vision loss. Further studies are warranted to more precisely evaluate the risks and benefits of LMT in ARMD.

Treatment of idiopathic subfoveal choroidal neovascular lesions using photodynamic therapy with verteporfin

PURPOSE

To report the effects of photodynamic therapy using verteporfin in the treatment of patients with subfoveal idiopathic choroidal vascularization (CNV).

DESIGN

Interventional case series.

METHODS

In a retrospective study, eight eyes of eight consecutive patients aged 55 years or younger with subfoveal idiopathic CNV treated with photodynamic therapy using verteporfin were evaluated. Visual acuity was considered to be improved if the visual angle was halved, while acuity was thought to be worse if the visual angle doubled.

RESULTS

The eight patients included three men and five women with a mean (+/- SD) age of 34.6 (+/- 9.7) years (range 25-53 years). The mean follow-up time was 13.5 months. At the end of the follow-up period the visual acuity improved in five eyes (62.5%), remained unchanged in one (12.5%), and decreased in two (25%). The mean acuity improvement was 3.6 lines of Snellen acuity by the end of the follow-up period, a change that was statistically significant (P =.027, Wilcoxon signed-rank test). No patient had any complication from the treatment.

CONCLUSIONS

There is no widely accepted method for treating subfoveal idiopathic CNV and all previously investigated methods have had a significant number of serious side effects. Although the follow-up time and the number of patients in this pilot study were limited, the encouraging results and lack of complications suggest that further study is indicated.

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.

Successful macular translocation with temporary scleral infolding using absorbable sture

PURPOSE

To describe successful macular translocation with temporary scleral infolding in a series of patients with small subfoveal choroidal neovascularization due to age-related macular degeneration or ocular histoplasmosis syndrome.

METHODS

Ten eyes of 10 consecutive patients were studied in a prospective, nonrandomized clinical trial. Macular translocation with scleral infolding (MTSI) was performed. Absorbable polyglactin suture was used to create temporary scleral infolding. Distance and stability of retinal translocation, corneal topography, visual acuity, and rates of complications were measured.

RESULTS

The median distance of translocation in the early postoperative period was 1,700 microm (range, 680-3,200) and did not regress after resolution of the scleral infolding. Induced postoperative oblique corneal astigmatism resolved, coinciding with the disappearance of peripheral retinal elevation due to scleral infolding. Three patients gained more than two lines of vision, two patients were within two lines of preoperative vision, and five patients lost more than two lines of vision. Complications were similar to previously published reports.

CONCLUSION

Temporary scleral infolding is an effective technique in MTSI. The distance of translocation is comparable to that achieved with nonabsorbable suture or scleral resection, and does not regress after resolution of the scleral infolding. Induced postoperative corneal astigmatism appears to resolve.

Macular fold after limited macular translocation treated with scleral shortening release and intravitreal gas

PURPOSE

To describe a case developing a macular fold as a complication of limited macular translocation, which was successfully managed without repeat vitrectomy.

METHODS

Interventional case report. A 34-year-old woman who underwent limited macular translocation for subfoveal choroidal neovascularization secondary to myopic degeneration developed a postoperative macular fold. Her visual acuity deteriorated from 20/100 to 20/200 postoperatively.

RESULTS

She underwent scleral shortening release and intravitreal gas injection 4 days after the initial surgery and had a resolution of macular fold with adequate foveal displacement. Her visual acuity had improved to 20/40 3 months postoperatively.

CONCLUSION

Scleral shortening release and intravitreal gas injection may be considered for the management of severe macular fold caused by limited macular translocation.

Neovascular age-related macular degeneration: present and future treatment options

PURPOSE

To review treatment strategies in neovascular age-related macular degeneration (ARMD).

METHODS

Medline and Embase search.

RESULTS

Age-related macular degeneration (ARMD) is the commonest cause of blindness in the developed world in individuals over 50 years of age. ARMD may lead to loss of vision by atrophy of the retinal pigment epithelium or by the development of choroidal neovascular membranes (CNVM) under the macula, which leak serous fluid and blood and ultimately cause a blinding disciform scar. Treatment options currently being investigated fall into three main approaches: elimination of the CNVM from the subfoveal area (by laser or surgery), modification of the CNVM (by laser, radiotherapy or chemotherapeutic agents) or lastly prevention of the formation of CNVM (by laser prophylaxis, diet or gene targeting). Whilst almost no therapy restores normal visual acuity, any significant visual improvement over the natural history may be regarded as beneficial.

CONCLUSIONS

Both the current and immediate future potential therapies for choroidal neovascularisation in ARMD require considerable advances to be made before they will make any impact on blindness caused by ARMD. Of the current treatments none are curative and the treatment benefits are small. There is an urgent need for new therapies.

Transient formed visual hallucinations following macular translocation for subfoveal choroidal neovascularization secondary to age-related macular degeneration

PURPOSE

To report the occurrence of transient formed visual hallucinations following macular translocation.

METHODS

Two case reports.

RESULTS

Two white women aged 84 and 83 years with bilateral age-related macular degeneration and unilateral subfoveal choroidal neovascularization underwent macular translocation with punctate retinotomy (limited macular translocation) and chorioscleral infolding in the eye with neovascularization. They complained of formed visual hallucinations which began within 24 hours following macular translocation and ceased 7 and 3 days postoperatively, respectively. Their symptoms occurred in the presence of normal cognition, orientation and insight, were not associated with other psychiatric symptoms, and were characteristic of Charles Bonnet syndrome (CBS).

CONCLUSION

The temporary deliberate retinal detachment and/or poor vision following macular translocation may be associated with postoperative CBS, and this report extends the spectrum of conditions associated with CBS.

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.