Retinal structure in vitamin A deficiency as explored with multimodal imaging

Intraretinal hemorrhages and detailed retinal phenotype of three patients with Alagille syndrome

PURPOSE

To explore patterns of disease expression in Alagille syndrome (ALGS).

METHODS

Patients underwent ophthalmic examination, optical coherence tomography (OCT) imaging, fundus intravenous fluorescein angiography (IVFA), perimetry and full-field electroretinograms (ffERGs). An adult ALGS patient had multimodal imaging and specialized perimetry.

RESULTS

The proband (P1) had a heterozygous pathogenic variant in JAG1; (p.Gln410Ter) and was incidentally diagnosed at age 7 with a superficial retinal hemorrhage, vascular tortuosity, and midperipheral pigmentary changes. The hemorrhage recurred 15 months later. Her monozygotic twin sister (P2) had a retinal hemorrhage at the same location at age 11. Visual acuities for both patients were 20/30 in each eye. IVFA was normal. OCT showed thinning of the outer nuclear in the peripapillary retina. A ffERG showed normal cone-mediated responses in P1 (rod-mediated ERGs not documented), normal ffERGs in P2. Coagulation and liver function were normal. An unrelated 42-year-old woman with a de-novo pathogenic variant (p. Gly386Arg) in JAG1 showed a similar pigmentary retinopathy and hepatic vascular anomalies; rod and cone function was normal across large expanses of structurally normal retina that sharply transitioned to a blind atrophic peripheral retina.

CONCLUSION

Nearly identical recurrent intraretinal hemorrhages in monozygotic twins with ALGS suggest a shared subclinical microvascular abnormality. We hypothesize that the presence of large areas of functionally and structurally intact retina surrounded by severe chorioretinal degeneration, is against a predominant involvement of JAG1 in the function of the neurosensory retina, and that instead, primary abnormalities of chorioretinal vascular development and/or homeostasis may drive the peculiar phenotypes.

Optical Coherence Tomography Findings in Glaucoma With Coexisting Vitamin A Deficiency

This case study reports on the presence of vitamin A deficiency in an adult with asymmetric normal tension glaucoma. The retinal OCT findings demonstrated not only expected loss of the outer retinal layers, typically seen in vitamin A deficiency, but also severe and bilateral loss of the inner retinal layers. After vitamin A supplementation, visual acuity, dark adaptation, and color vision normalized. The outer retinal layers had a restoration of thickness after vitamin A supplementation, but the inner layers did not change. This case is unique because it may give us an insight into the role of vitamin A on the inner retina and demonstrate the recovery of the outer retinal layers with vitamin A supplementation.

Vitamin A deficiency retinopathy in the setting of celiac disease and liver fibrosis

PURPOSE

Vitamin A is a lipid-soluble compound that is critical in maintaining phototransduction. Ocular manifestations of hypovitaminosis A may present with anterior segment signs of xeropthalmia, with advanced cases also causing classic retinal and electrophysiologic changes of vitamin A deficiency retinopathy. We present a case of vitamin A deficiency retinopathy, with corresponding retinal imaging and electrophysiology, in an adult patient with celiac disease and liver fibrosis.

METHODS

A single case report was conducted in Toronto, Canada.

RESULTS

A 77-year-old male with known celiac disease and liver fibrosis presented progressively worsening vision noticed primarily when driving. Vision was 20/50 OD and 20/200 OS. Bitot spots were noted on anterior segment examination. Fundus photography demonstrated bilateral peripheral macular hypopigmentation and far-peripheral granular retinal hypopigmentation with focal yellow dots and hyper-pigmented deposits. Optical coherence tomography (OCT) imaging demonstrated indistinct outer retinal banding with mild outer nuclear layer thinning, focal hyper-reflective deposits, and a thin choroid bilaterally. Full-field electroretinography (ERG) testing demonstrated reduced rod-isolated and combined rod-cone response amplitudes, and multifocal ERG testing demonstrated blunted individual responses throughout the field. The patient was treated with pulse vitamin A therapy. After 6 months of therapy, ERG responses were back within reference range, and the outer retinal changes reversed; visual acuity improved to 20/30 OD and 20/40 OS.

CONCLUSION

This case represents the classic findings of vitamin A deficiency retinopathy on fundus examination and electrophysiologic testing secondary to gastrointestinal pathology. Prompt treatment of high dose vitamin A supplementation led to improvement of full-field and multifocal ERG results, as well as reconstitution of outer retinal architecture.

Case of persistent corneal epithelial damage after cataract surgery leading to diagnosis of vitamin A deficiency

PURPOSE

To report our findings of reduced full-field electroretinograms (ff-ERGs) and abnormal optical coherence tomographic (OCT) images in a patient with poor visual acuity after cataract surgery who was eventually diagnosed with vitamin A deficiency (VAD).

METHODS

This was a clinical study of a patient who complained of blurred vision after cataract surgery. To determine the cause of the reduced vision, we recorded full-field electroretinograms (ff-ERGs) to determine the scotopic and photopic status of the retina. We also performed optical coherence tomography to assess the changes in the retinal structure. Serological tests were performed.

RESULTS

A 74-year-old man presented with persistent corneal epithelial damages and reduced vision that developed after conventional cataract surgery. OCT showed an interrupted ellipsoid zone, and fundus autofluorescence (FAF) showed a severe hypofluorescence in the retina of the left eye. The scotopic ff-ERGs were severely reduced, and the photopic ff-ERGs were mildly reduced. Serological examinations revealed a vitamin A concentration < 7 IU/dL (normal, 97-316 IU/dL). Based on these findings, we diagnosed the patient with VAD and started treatment with oral vitamin A supplements. After three months, his visual acuity, ff-ERGs, and OCT findings recovered to normal levels. The amplitudes and implicit times of the RETeval flicker ERGs increased to be within the normal range, and the hypofluorescence of the left eye disappeared. The length of the photoreceptor outer segments increased after the vitamin A supplementation.

CONCLUSION

Our findings indicate that the ERGs are helpful for diagnosing patients with VAD associated with persistent corneal epithelial damages.

Characteristics of Vitamin A Deficiency Retinopathy at a Tertiary Referral Center in the United States

PURPOSE

To explore the risk factors and fundus imaging features of vitamin A deficiency retinopathy (VADR) in an academic tertiary referral center in Atlanta, GA, United States, and to propose guidance regarding diagnostic workup and management of affected patients.

DESIGN

Single-center retrospective case series.

SUBJECTS

Nine patients seen between 2015 and 2021 at the Emory Eye Center diagnosed with VADR.

METHODS

Retrospective chart review.

MAIN OUTCOME MEASURES

Baseline serum retinol level, Snellen visual acuity, multimodal fundus imaging findings, and electroretinography findings.

RESULTS

Nine patients, 4 (44.4%) female, with a median (range) age of 68 (50-75) years were identified. The most common underlying etiologies for vitamin A deficiency included history of gastrointestinal surgery (55.6%), liver disease (44.4%), and nutritional depletion due to low-quality diet (44.4%). Only 1 (11.1%) patient had a history of bariatric surgery. Four (44.4%) patients were on some form of vitamin A supplementation before the diagnosis of VADR. Median (range) serum retinol level was 0.06 (< 0.06-0.19) mg/L. All patients had macular subretinal hyperreflective deposits resembling subretinal drusenoid deposits, although in some cases, these were scant and sparsely distributed. Six eyes of 3 patients with longstanding deficiency had defects in the external limiting membrane (ELM). Three of these eyes additionally had macular areas of complete retinal pigment epithelium and outer retinal atrophy (cRORA). Full-field electroretinography demonstrated severe rod dysfunction and mild to moderate cone system dysfunction. Many findings of VADR were reversible with vitamin A repletion. However, all eyes with ELM defects or cRORA had persistence or continued growth of these lesions.

CONCLUSION

Vitamin A deficiency retinopathy is uncommon in the developed world. However, given that early intervention can lead to dramatic visual improvement and avoid potentially permanent retinal damage, retina specialists should be familiar with its clinical presentation. The presence of nyctalopia and subretinal hyperreflective deposits in a patient with a history of gastrointestinal surgery, liver disease, and/or poor diet can be suggestive of this diagnosis, even in the presence of ongoing vitamin A supplementation. Vitamin A supplementation can vary in route and dosage and can be tailored to the individual with serial testing of serum retinol.

FINANCIAL DISCLOSURE(S)

The authors have no proprietary or commercial interest in any materials discussed in this article.

Fat-soluble vitamin deficiency and exocrine pancreatic insufficiency among adults with chronic pancreatitis: Is routine monitoring necessary for all patients?

Chronic pancreatitis (CP) is often associated with exocrine pancreatic insufficiency (EPI), which may increase risk for fat-soluble vitamin depletion. Although vitamin D deficiency is widespread among the general population, vitamins A, E, and K deficiencies may more uniquely present in patients with CP. Yet, it is unclear whether fat-soluble vitamin status should be routinely monitored in all patients with CP or limited to those with EPI. The purpose of this review is to describe the laboratory status of vitamins A, E, and K in adult patients with CP and their association with exocrine pancreatic function. Five primary, observational studies met the inclusion criteria for qualitative synthesis. Biochemical deficiencies in fat-soluble vitamins were observed across trials but results varied with respect to whether EPI increased risk. Challenges related to the diagnosis and treatment of EPI along with potential confounders may contribute to the heterogeneity among study results. Although more studies are needed to determine the influence of pancreatic enzyme replacement therapy on fat-soluble vitamin status as well as effective vitamin repletion strategies, clinicians should consider periodically screening for deficiencies in all patients with CP regardless of EPI to avoid associated health effects of vitamin depletion.

Vitamin A deficiency retinopathy related to medical interventions in a Swiss cohort: a case series

AIMS OF THE STUDY

Vitamin A deficiency retinopathy is a potentially blinding disease. In developed countries, vitamin A deficiency due to malnutrition is rare. However, vitamin A deficiency can be caused by malabsorption resulting from bowel resection or medication. In this retrospective study, we present five cases of vitamin A deficiency retinopathy related to malabsorption secondary to medical interventions.

METHODS

Electronic charts over a ten-year period (2012-2022) were screened for vitamin A deficiency retinopathy. Only patients with vitamin A deficiency confirmed by laboratory tests were included. Symptoms, medical history, visual acuity, optical coherence tomography, fundus autofluorescence, electrophysiological examination, and vitamin A levels were reviewed.

RESULTS

Five eligible cases were identified. Median age was 44.7 years (range 22.2-88.9), median duration of ocular symptoms prior to diagnosis was 14 months, and median visual acuity was 1.0 (range 0.5-1.0, Snellen, decimal). Three patients had a history of bariatric surgery, one patient had a small bowel resection and was on octreotide treatment, and one patient suffered from cystic fibrosis and had a history of small bowel resection and severe hepatopathy. Optical coherence tomography showed various abnormalities, including a reduced interdigitation zone, subretinal drusenoid deposits, and a thinned outer nuclear layer. Electroretinogram findings ranged from abnormal oscillatory potentials to non-recordable rod responses.

CONCLUSIONS

Vitamin A deficiency retinopathy can occur following medical interventions associated with malabsorption. In cases of night blindness, vitamin A levels should be measured.

Multimodal Imaging Study of Patients With Vitamin A Deficiency Retinopathy

OBJECTIVES

To describe multimodal imaging findings of vitamin A deficiency retinopathy.

METHODS

A retrospective study of patients with serum retinol < 0.3 mg/L. Fundus color photos, spectral domain-optical coherence tomography (SD-OCT), and fundus autofluorescence (FAF) were reviewed and, when available, electrophysiological tests were analyzed.

RESULTS

Forty-five eyes (63.9 ± 15.7 years) were included. Ultra-widefield fundus photography showed drusen-like deposits (53.3%) and macular retinal pigment epithelium (RPE) mottling (40%). The deposits were hypoautofluorescent, and a perifoveal hyperautofluorescent ring was present in 8.9%. By SD-OCT, the ellipsoid zone had an irregular appearance (100%) and conical deposits anterior to the RPE (33.3%). Electroretinogram (ERG) (66.7%) showed a decrease in b-wave in the scotopic registers, and microperimetry (4.4%) showed decreased foveal sensitivity. After vitamin A supplementation, SD-OCT and FAF showed resolution of all findings. Forty percent of eyes had restoration of the scotopic registers in ERG and improved macular sensitivity by microperimetry (4.4%).

CONCLUSIONS

Vitamin A deficiency causes a mild cone dysfunction in addition to the more severe absent rod response. [Ophthalmic Surg Lasers Imaging Retina 2023;54:330-336.].

Vitamin A deficiency and the retinal "double carrot" sign with optical coherence tomography

BACKGROUND

Spectral-domain optical coherence tomography (SD-OCT) and full-field electroretinography (ERG) allow retinal assessment with vitamin A deficiency (VAD). Using SD-OCT, this study aimed to characterize and follow a novel retinal abnormality in patients with VAD and intramuscular supplementation.

METHODS

Patients with VAD were retrospectively reviewed, including SD-OCT and electroretinography.

RESULTS

Three patients had VAD following bariatric or colon surgery and varying supplementation. All had nyctalopia, extinguished scotopic rod-specific function with ERG, and decreased serum vitamin A. None demonstrated surface abnormalities. All received intramuscular vitamin A with subjective resolution of symptoms. On SD-OCT, four of six eyes exhibited homogenous foveal hyperreflectivity anterior to retinal pigment epithelium-Bruch complex, reminiscent of a "double carrot", which improved following supplementation. ERG findings demonstrated improved scotopic rod-specific function in all cases; however, photopic function remained diminished in two cases.

CONCLUSIONS

Structural improvement of the proposed "double carrot" sign occurs soon after vitamin A supplementation. While scotopic function improves rapidly following supplementation, cone function recovers more slowly. Therefore, foveal changes such as the "double carrot" sign suggest that structural recovery of cones precedes functional recovery.

A comparison of optophysiological biomarkers of photoreceptor stress and phototoxicity in BALB/cJ, B6 (Cg)-Tyrc-2J/J, and C57Bl/6J mouse strains

Ophthalmic imaging instruments, including the confocal scanning laser ophthalmoscope and spectral-domain optical coherence tomography system, originally intended for revealing ocular microstructures in the human eye, have been deployed by vision researchers to evaluate the eyes of numerous small and large animal species for more than two decades. In this study, we have used these two instruments to obtain imaging data sequentially from the retinas of three prominent, widely used experimental mouse models to document changes induced by two contrasting vivarium lighting conditions. Mice studied include albino BALB/cJ and B6(Cg)-Tyrc-2J/J and pigmented C57Bl/6J. Mice were reared under dim light conditions until ~8 weeks of age where they underwent baseline imaging. Following, mice were returned to the dim vivarium or relocated to the top rack cage position in a standard vivarium. Mice were then followed for several months by ocular imaging to catalog the retinal dynamics as a function of long-term dim vs. elevated, standard vivarium lighting exposure levels. Upon exposure to elevated light levels, B6(Cg)-Tyrc-2J/J underwent similar changes as BALB/cJ in regard to photoreceptor outer segment shortening, photoreceptor layer proximal aspect hyperreflective changes, and the development of retinal infoldings and autofluorescent sub-retinal inflammatory monocyte infiltrate. Noteworthy, however, is that infoldings and infiltrate occurred at a slower rate of progression in B6(Cg)-Tyrc-2J/J vs. BALB/cJ. The photoreceptor outer nuclear layer thickness of BALB/cJ degenerated steadily following elevated light onset. In contrast, B6(Cg)-Tyrc-2J/J degeneration was unremarkable for many weeks before experiencing a noticeable change in the rate of degeneration that was concomitant with a plateau and decreasing trend in number of retinal infoldings and monocyte infiltrate. Pathological changes in C57Bl/6J mice were unremarkable for all imaging biomarkers assessed with exception to autofluorescent sub-retinal inflammatory monocyte infiltrate, which showed significant accumulation in dim vs. elevated light exposed mice following ~1 year of observation. These data were evaluated using Spearman's correlation and Predictive Power Score matrices to determine the best imaging optophysiological biomarkers for indicating vivarium light stress and light-induced photoreceptor degeneration. This study suggests that changes in proximal aspect hyperreflectivity, outer segment shortening, retinal infoldings and autofluorescent sub-retinal inflammatory monocyte infiltrate are excellent indicators of light stress and light-induced degeneration in albino B6(Cg)-Tyrc-2J/J and BALB/cJ mouse strains.

Bilateral compressive optic neuropathy and outer retinopathy due to optic canal hyperostosis in a child with isolated vitamin a deficiency

PURPOSE

Vitamin A plays a crucial role in rod phototransduction, with deficient levels manifesting as night blindness. Animal models have demonstrated bone dysplasia in the setting of hypovitaminosis A. We present a rare case of bony overgrowth leading to bilateral compressive optic neuropathy, combined with outer retinopathy, in a paediatric patient secondary to isolated vitamin A deficiency.

METHODS

A single case report was conducted from Toronto, Canada.

RESULTS

A 12-year-old boy with known autism spectrum disorder presented with a 9-month history of progressive painless vision loss. Vision was 20/300 and hand motion in the right and left eye, respectively. Fundus photography demonstrated bilateral optic atrophy and yellow lesions notably in the right eye far periphery. Optical coherence tomography (OCT) imaging demonstrated thinning of the retinal nerve fibre layer, alterations in the ellipsoid zone, as well as retinal pigment epithelium deposits. Computed tomography imaging demonstrated sphenoid bone thickening with narrow optic canals and moderate optic atrophy bilaterally. Full-field electroretinogram (ERG) demonstrated mildly reduced dark adapted (DA) 0.01 b-wave amplitudes and electronegative configuration of DA 3.0 and DA 10.0 ERG; the light adapted ERGs were normal. The patient was treated with pulse vitamin A therapy. Subsequently, the DA ERG normalized, outer retinal changes reversed and vision stabilised; no surgical intervention was conducted.

CONCLUSION

This case represents a rare presentation of compressive optic neuropathy with concomitant outer retinopathy secondary to isolated vitamin A deficiency. Despite improvement in outer retinal integrity on OCT imaging and ERG testing results following vitamin A supplementation, no functional improvement was obtained due to severe optic atrophy.

Correlation between the Serum Concentration of Vitamin A and Disease Severity in Patients Carrying p.G90D in RHO, the Most Frequent Gene Associated with Dominant Retinitis Pigmentosa: Implications for Therapy with Vitamin A

The pathogenic variant p.G90D in RHO is believed to be responsible for a spectrum of phenotypes, including congenital stationary blindness (for the purpose of this study termed night blindness without degeneration; NBWD), Sector RP, Pericentral RP, and Classic RP. We present a correlation between the serum concentration of vitamin A and disease severity in patients with this variant. This prospective study involved 30 patients from 7 families (17 male; median age 46 years, range 8−73). Full ophthalmological examination including visual acuity, Goldmann perimetry, slit-lamp exam, optical coherence tomography, fundus autofluorescence, and electrophysiology was performed to determine the presenting phenotype. The serum concentration of vitamin A was determined from a fasting blood sample taken on the day of the exam, where it was found that 23.3% (7/30) of patients had NBWD, 13.3% (4/30) had Sector RP, 3.3% (1/30) had Pericentral RP, and 60% (18/30) had Classic RP. Multiple logistic regression revealed a significantly higher probability of having a milder phenotype (NBWD or Sector RP) in association with younger age (p < 0.05) and a higher concentration of vitamin A (p < 0.05). We hypothesize that vitamin A in its 11-cis-retinal form plays a role in stabilizing the constitutively active p.G90D rhodopsin and its supplementation could be a potential treatment strategy for p.G90D RHO patients.

Posterior placoid-like maculopathy and macular hole associated with vitamin A deficiency

Purpose

To report a case of bilateral posterior placoid-like maculopathy and a macular hole associated with vitamin A deficiency.

Observations

A 72-year-old male presented with nyctalopia and progressive vision loss in both eyes. Examination and multimodal imaging were consistent with posterior placoid-like maculopathy bilaterally and a macular hole in the right eye. A workup for infectious, inflammatory, and paraneoplastic etiologies revealed a severely low serum vitamin A level. Two months after initiation of vitamin A repletion, there was improvement in best-corrected Snellen visual acuity as well as macular hole closure. A diagnosis of posterior placoid-like maculopathy in the setting of vitamin A deficiency (VAD) was made.

Conclusions and importance

VAD should be considered when symmetric posterior pole placoid-like lesions are observed and other, more common etiologies have been ruled out.

Fleck-like lesions in CEP290-associated leber congenital amaurosis: a case series

PURPOSE

To provide a detailed ophthalmic phenotype of a small cohort of patients with Leber Congenital Amaurosis (LCA) caused by mutations in CEP290 (CEP290-LCA) with a focus on elucidating the origin of yellow-white lesions observed in 30% of patients with this condition.

METHODS

This is a retrospective review of records of five patients with CEP290-LCA. Patients had comprehensive ophthalmic evaluations. Visual function was assessed with full-field electroretinograms (ffERGs) and full-field sensitivity testing (FST). Multimodal imaging was performed with spectral domain optical coherence tomography (SD-OCT), fundus autofluorescence (FAF) with short- (SW) and near-infrared (NIR) excitation wavelengths.

RESULTS

All patients showed relative structural preservation of the foveal and near midperipheral retina separated by a pericentral area of photoreceptor loss. Yellow-white, fleck-like lesions in an annular distribution around the near midperiphery co-localized with hyperreflective lesions on SD-OCT. The lesions located between the inner segment ellipsoid signal and the apical retinal pigment epithelium (RPE). The inner retina was normal. Longitudinal observations in one of the patients indicates the abnormalities may represent an intermediate stage in the degenerative process between the near normal appearing retina previously documented in young CEP290-LCA patients and the pigmentary retinopathy observed along the same region in older individuals.

CONCLUSIONS

We speculate that fleck-like lesions in CEP290-LCA correspond to malformed, rudimentary or degenerated, including shed, photoreceptor outer segments. The topography and possible origin of the abnormalities may inform the planning of evolving genetic therapies for this disease.

DISRUPTION OF THE OUTER SEGMENTS OF THE PHOTORECEPTORS ON OPTICAL COHERENCE TOMOGRAPHY AS A FEATURE OF VITAMIN A DEFICIENCY

PURPOSE

To describe the optical coherence tomography features of vitamin A deficiency.

METHODS

Case series includes three male patients aged 50 to 66 years with vitamin A deficiency and visual symptoms ranging from 2 to 8 months. Examination included optical coherence tomography (OCT), fundus autofluorescence imaging, full-field electroretinography6 and laboratory work-up.

RESULTS

Patient 1 had inoperable pancreatic neuroendocrine tumor and presented with worsening nyctalopia. The electroretinography showed absent rod function 2 months after the onset of symptoms, followed by a decrease of the cone function eight months after the onset. Optical coherence tomography showed poorly distinguishable outer segments of the photoreceptors with the disappearance of the interdigitation zone. At that time, vitamin A deficiency along with several other deficiencies was confirmed. After the initiation of parenteral nutrition, a substantial improvement of the patient's overall well-being was noted and the OCT showed normalization of the retinal structure. Two other patients were diagnosed with vitamin A deficiency based on similar OCT features.

CONCLUSION

Disruption of the outer segments of the photoreceptors and the disappearance of the interdigitation zone on OCT may be helpful in recognition of vitamin A deficiency. Early detection and malnutrition evaluation are especially important in patients with a history of gastrointestinal disorders who may have several other underlying deficiencies. Treatment with either enteral or parenteral nutrition not only leads to resolution of visual symptoms but vastly improves their general condition and quality of life.

Documentation of recovery from vitamin A deficiency-related retinopathy via multimodal imaging and electroretinogram testing

PURPOSE

To describe vitamin A deficiency using multimodal functional visual assessments and imaging.

METHODS/CASE

A 50-year-old female with past medical history significant for Roux-en-Y gastric bypass surgery complained of nyctalopia and "yellowing" of vision.

RESULTS

Vitamin A levels were noted to be < 0.06 mg/L (normal 0.3-0.12 mg/L). Fundus examination was notable for peripheral yellow punctate lesions, superior arcuate defects on HVF 30-2 testing, an indistinct ellipsoid zone on SD-OCT, and absent rod responses and severely reduced amplitudes for the cone photoreceptors on full-field ERG. These findings resolved with initiation of parenteral vitamin A supplementation.

CONCLUSION

This report documents an example of vitamin A deficiency in the developed world. We aim to provide a comprehensive description of clinical examination and multimodal imaging findings before and after vitamin supplementation for vitamin A deficiency.

Large Benefit from Simple Things: High-Dose Vitamin A Improves RBP4-Related Retinal Dystrophy

Inherited retinal diseases (IRD) are a group of heterogeneous disorders, most of which lead to blindness with limited therapeutic options. Pathogenic variants in RBP4, coding for a major blood carrier of retinol, retinol-binding protein 4, are responsible for a peculiar form of IRD. The aim of this study was to investigate if retinal function of an RBP4-related IRD patient can be improved by retinol administration. Our patient presented a peculiar white-dot retinopathy, reminiscent of vitamin A deficient retinopathy. Using a customized next generation sequencing (NGS) IRD panel we discovered a novel loss-of-function homozygous pathogenic variant in RBP4: c.255G >A, p.(Trp85*). Western blotting revealed the absence of RBP4 protein in the patient’s serum. Blood retinol levels were undetectable. The patient was put on a high-dose oral retinol regimen (50,000 UI twice a week). Subjective symptoms and retinal function markedly and sustainably improved at 5-months and 1-year follow-up. Here we show that this novel IRD case can be treated by oral retinol administration.

The Role of Vitamin A in Retinal Diseases

Vitamin A is an essential fat-soluble vitamin that occurs in various chemical forms. It is essential for several physiological processes. Either hyper- or hypovitaminosis can be harmful. One of the most important vitamin A functions is its involvement in visual phototransduction, where it serves as the crucial part of photopigment, the first molecule in the process of transforming photons of light into electrical signals. In this process, large quantities of vitamin A in the form of 11-cis-retinal are being isomerized to all-trans-retinal and then quickly recycled back to 11-cis-retinal. Complex machinery of transporters and enzymes is involved in this process (i.e., the visual cycle). Any fault in the machinery may not only reduce the efficiency of visual detection but also cause the accumulation of toxic chemicals in the retina. This review provides a comprehensive overview of diseases that are directly or indirectly connected with vitamin A pathways in the retina. It includes the pathophysiological background and clinical presentation of each disease and summarizes the already existing therapeutic and prospective interventions.

Subretinal drusenoid deposits: An update

A wide spectrum of phenotypic manifestations characterizes age-related macular degeneration (AMD). Drusen is considered the hallmark of AMD and is located underneath the retinal pigment epithelium (RPE). In contrast, subretinal drusenoid deposits (SDDs), also known as reticular pseudodrusens, are located in the subretinal space, on top of the RPE. SDDs are poorly detected by clinical examination and color fundus photography. Multimodal imaging is required for their proper diagnosis. SDDs are topographically and functionally related to rods. SDDs cause a deep impairment in retinal sensitivity and dark adaptation. SDDs are dynamic structures that may grow, fuse with each other, or regress over time. An intermediate step in some eyes is the development of an acquired vitelliform lesion. The presence of SDD confers an eye a high risk for the development of late AMD. SDD leads to macular neovascularization, particularly type 3, geographic atrophy, and outer retinal atrophy.

Acquired night blindness due to rod dysfunction after long-term hemodialysis

PURPOSE

To report the clinical findings in 6 patients who developed night blindness after long-term hemodialysis.

STUDY DESIGN

Retrospective case series.

PATIENTS AND METHODS

The medical charts of the 6 patients were examined. The fundus photographs, spectral-domain optical coherence tomographic (SD-OCT) images, full-field ERGs, and blood chemistry panels were analyzed.

RESULTS

The mean age of the 6 patients (4 men) at the time of diagnosis was 69.1 ± 5.9 years. The mean duration of the hemodialysis was 21.8 ± 13.4 years (7-41 years). The visual acuity of the patients was preserved at 20/30 or better except in 1 eye. Ophthalmoscopy showed white flecks that were scattered over the midperipheral retina in all the eyes. SD-OCT showed mild macular degeneration in 5 eyes. The scotopic ERGs elicited by dim flashes were absent, and those elicited by bright flashes had negative waveforms. The photopic ERGs were relatively well preserved. These data indicated a rod-specific dysfunction that may account for the night blindness. The plasma concentration of vitamin A was within the normal range in 4 of the patients and slightly lower than the normal limit in 1 of the patients. Administration of vitamin A was performed for 1 patient, and the symptom of night blindness and scotopic ERGs were improved 3 months later.

DISCUSSION

Long-term hemodialysis can be associated with the night blindness that may be caused by vitamin A deficiency, even though the plasma concentration of vitamin A in these patients was within the normal range.

Reticular pseudodrusen: A critical phenotype in age-related macular degeneration

Reticular pseudodrusen (RPD), or subretinal drusenoid deposits (SDD), refer to distinct lesions that occur in the subretinal space. Over the past three decades, their presence in association with age-related macular degeneration (AMD) has become increasingly recognized, especially as RPD have become more easily distinguished with newer clinical imaging modalities. There is also an increasing appreciation that RPD appear to be a critical AMD phenotype, where understanding their pathogenesis will provide further insights into the processes driving vision loss in AMD. However, key barriers to understanding the current evidence related to the independent impact of RPD include the heterogeneity in defining their presence, and failure to account for the confounding impact of the concurrent presence and severity of AMD pathology. This review thus critically discusses the current evidence on the prevalence and clinical significance of RPD and proposes a clinical imaging definition of RPD that will help move the field forward in gathering further key knowledge about this critical phenotype. It also proposes a putative mechanism for RPD formation and how they may drive progression to vision loss in AMD, through examining current evidence and presenting novel findings from preclinical and clinical studies.

Reticular Pseudodrusen in Late-Onset Retinal Degeneration

PURPOSE

To characterize the association of reticular pseudodrusen (RPD) with late-onset retinal degeneration (L-ORD) using multimodal imaging.

DESIGN

Prospective, 2-center, longitudinal case series.

PARTICIPANTS

Twenty-nine patients with L-ORD.

METHODS

All patients were evaluated within a 3-year interval with near-infrared reflectance, fundus autofluorescence, and spectral-domain OCT. In addition, a subset of patients also underwent indocyanine green angiography, fundus fluorescein angiography, mesopic microperimetry, and multifocal electroretinography.

MAIN OUTCOME MEASURES

Prevalence, topographic distribution, and temporal phenotypic changes of RPD in L-ORD.

RESULTS

A total of 29 patients with molecularly confirmed L-ORD were included in this prospective study. Reticular pseudodrusen was detected in 18 patients (62%) at baseline, 10 of whom were men. The prevalence of RPD varied with age. The mean age of RPD patients was 57.3 ± 7.2 years. Reticular pseudodrusen was not seen in patients younger than the fifth decade of life (n = 3 patients) or in the eighth decade of life (n = 5 patients). Reticular pseudodrusen were found commonly in the macula with relative sparing of the fovea and also were identified in the peripheral retina. The morphologic features of RPD changed with follow-up. Two patients (3 eyes) demonstrated RPD regression.

CONCLUSIONS

Reticular pseudodrusen is found frequently in patients with L-ORD and at a younger age than in individuals with age-related macular degeneration (AMD). Reticular pseudodrusen exhibits quick formation and collapse, change in type and morphologic features with time, and relative foveal sparing and also has a peripheral retinal location in L-ORD.

Vitamin A retinopathy secondary to Billroth II anastomosis triggered after the beginning of dialysis

PURPOSE

To report a case of vitamin A retinopathy secondary to Billroth II anastomosis triggered after the beginning of dialysis in a patient with a chronic renal failure.

CASE REPORT

A 73-year-old male complained of nyctalopia that had started 9 months ago, coinciding with the beginning of dialysis. His medical history is remarkable for hepatic cirrhosis and Billroth II anastomosis 20 years ago. Best-corrected visual acuity (BCVA) was 60 letters in both eyes. Dilated fundus examination showed faint white-yellowish dots. Optical coherence tomography (OCT) illustrated hyperreflective dots and small hyporreflective cavities between the retinal pigment epithelium (RPE) and the ellipsoid zone (EZ). En face OCT showed multiple hyperreflective dots that coincide with white-yellowish dots of the fundus, and multiple hyporreflective defects which correspond to hyporreflective cavities seen in the OCT. Visual field examination showed concentric narrowing of the visual field. A diagnosis of vitamin A deficiency was confirmed and oral vitamin A supplementation was initiated. One month after treatment, the patient reported a subjective improvement of nyctalopia, and BCVA ameliorated up to 80 and 85 letters. Fundus examination, OCT, and en face OCT showed a diminution of the observed lesions. Moreover, visual field improved.

CONCLUSION

Early diagnosis of vitamin A deficiency can prevent irreversible visual sequelae. This highlights the crucial role of ophthalmologists in the prompt detection of this condition. A lifelong monitoring should be needed in patients undergoing biliopancreatic diversion surgery. Furthermore, OCT and en face OCT becomes a main tool in the diagnosis and monitor response to treatment.

Shared Features in Retinal Disorders With Involvement of Retinal Pigment Epithelium

When using spectral domain optical coherence tomography (SD-OCT) to inform the status of outer retina, we have noted discrete hyperreflective lesions extending through photoreceptor-attributable bands that have a similar presentation in multiple retinal diseases. These lesions present as either corrugated thickenings of interdigitation zone and ellipsoid zone bands or in later stages as rectangular or pyramidal shaped foci that extend radially through photoreceptor cell-attributable bands. In ABCA4-related and peripherin-2/RDS-disease (PRPH2/RDS), monogenic forms of retinopathy caused by mutations in proteins expressed in photoreceptor cells, these punctate lesions colocalize with fundus flecks in en face images. In fundus albipunctatus and retinitis punctata albescens, diseases caused by mutations in genes (retinol dehydrogenase 5, RDH5; and retinaldehyde-binding protein 1, RLBP1) encoding proteins of the visual cycle, these lesions manifest as white dot-like puncta. Similar aberrations in photoreceptor cell-attributable SD-OCT reflectivity layers manifest as reticular pseudodrusen (RPD) in short-wavelength fundus autofluorescence and near-infrared fundus autofluorescence fundus images and are linked to age-related macular degeneration a complex disease. Despite differences in the etiologies of retinal diseases presenting as fundus flecks, dots and RPD, underlying degenerative processes in photoreceptor cells are signified in SD-OCT scans by the loss of structural features that would otherwise define healthy photoreceptor cells at these foci.

Vitamin A and Daucus carota root extract mitigate STZ-induced diabetic retinal degeneration in Wistar albino rats by modulating neurotransmission and downregulation of apoptotic pathways

The objective of our study was to explore the deleterious effects of diabetes on the visual functions of the retina and to address whether the administration of vitamin A and carrot root extract (CE) confer retinal protection in hyperglycemic rats via modulation of oxidative stress, biochemical alternations, and retinal neurotransmission. Fifty male Wistar albino rats weighing 180 ± 12.41 g were randomized into five groups (n = 10): controls, diabetic group (injected with 40 mg/kg dissolved in 0.1 sodium citrate buffer), diabetic group treated with vitamin A (2,500 IU/kg, low dose), diabetic group treated with vitamin (5,000 IU/kg, high dose), and diabetic groups administered CE (200 mg/kg/every other day). Our findings showed that, compared to controls, diabetic rats showed a significant decrease in their retinal thickness, increased apoptotic ganglion cells, and a noticeable degeneration of their synaptic layers. The inner retina displayed increased activity of neovascularization; however, the outer retina exhibited vacuolar degeneration of the photoreceptor cell layer. Our biochemical assessments showed reduced levels of CAT, SOD, and GST along with increased lipid peroxidation. Concurrently, cellular angiogenic and stress markers were significantly elevated associated with increased apoptotic activities as evidenced by increased expressions of annexin-V and PARP. Furthermore, the neurotransmitter content of the retina was altered in diabetic rats compared to controls and diabetic-treated groups. Paradoxically, vitamin A and CE supplementation attenuate these retinal insults in diabetic animals and normalized aforementioned assayed parameters; evidencing that both treatments exerted ameliorative impacts and restored visual functions by diminishing oxidative stress and neuronal degeneration. PRACTICAL APPLICATIONS: Diabetes is a complex disease that involves various physiological perturbations especially visual functions. In our study, we showed that vitamin A and carrot root extract (CE) confer remarkable protection against retinal degeneration in STZ-induced diabetic rats. Our findings showed that the chemical and phytochemical ingredients of the vitamin A and CE substantially attenuated the histopathological changes, oxidative stress, inflammatory reactions, and cellular death in diabetic rats. These favorable changes are attributable to the high content of retinoic acid, carotenoids, and phenolic compounds that effectively regulates the production of visual pigments, increases the antioxidant defense system, and diminishes the pro-inflammatory and apoptotic pathways. Thus, the nutritional values of vitamin A and CE represent promising therapeutic choices to mitigate the retinal-induced diabetic insults.

Vitamin A deficiency after prolonged intake of an unbalanced diet in a Japanese hemodialysis patient

BACKGROUND

In industrialized countries, vitamin A deficiency (VAD) is extremely rare, except association with bariatric surgeries and hepatobiliary disorders. It is unusual that VAD develops during hemodialysis due to reduced glomerular filtration of vitamin A-binding protein. We reported the case of a 58-year-old Japanese male hemodialysis patient diagnosed with VAD.

CASE PRESENTATION

The patient undergoing hemodialysis for more than 15 years presented with progressive photophobia and night blindness and was ophthalmologically examined. He denied a history of cancer or hepatobiliary disease and reported that he loved eating prepackaged noodle bowls and foods, with prolonged low intake of fruits/vegetables. He had good visual acuity. Fundus images showed numerous white dots in the midperipheral retinae, but no degenerative changes. In baseline full-field electroretinography (ERG), b-wave responses were extremely reduced in rod ERG, a-wave amplitudes in standard-flash/strong-flash ERG were reduced to 20-25% of our controls, a- and b-wave amplitudes in cone ERG were reduced to 40-50% of the controls. Whole-exome sequencing identified no pathogenic variant for any inherited retinal disorder. He was diagnosed with VAD because of reduced serum vitamin A levels and treated with retinol palmitate. Two months after treatment commencement, the serum vitamin A level was within the normal range. Full-field ERG showed that the scotopic ERG responses markedly improved compared with baseline.

CONCLUSIONS

This is the first report of VAD associated with undernutrition in the Japanese hemodialysis population.

Macular thickness analysis and resolution of subretinal drusenoid deposits with optical coherence tomography in vitamin A deficiency-related retinopathy

Purpose

To report the resolution of subretinal drusenoid deposits (SDDs) and the changes in macular thickness at various segmentation levels in a patient who was treated for vitamin A deficiency-related retinopathy.

Observations

A 67-year-old man with cirrhosis secondary to hepatitis C was referred for unexplained vision decline and nyctalopia. He was diagnosed with vitamin A deficiency after he was found to have yellow-white drusen-like deposits in the posterior pole and midperiphery, which corresponded to SDDs on optical coherence tomography (OCT). Treatment with vitamin A supplementation was initiated, and, over the course of eight months, the symptoms improved, the SDDs resolved, and retinal thickness generally increased, although the rate and pattern of change differed depending on the macular quadrant and the segmentation layer being analyzed.

Conclusions and importance

Vitamin A deficiency should be considered in patients with liver disease who present with drusen-like deposits in the macula and midperiphery. Prompt recognition and treatment may improve symptoms and reverse some retinal pathology, including the presence of SDDs. Vitamin A supplementation in these patients seems to affect the inner retina and outer retina differently.

Anti-Retinal Antibodies in Vitamin A Deficiency

Vitamin A is an important component of the visual cycle, and its deficiency causes a retinal degeneration that may be reversed with retinol supplementation. Here, the authors present a patient with vitamin A deficiency and rod-mediated retinopathy who was found to have multiple anti-retinal antibodies that gradually dissipated after vitamin A supplementation. This interesting case suggests the possibility that the photoreceptor degeneration induced by vitamin A deficiency may lead to transient immune exposure to retinal antigens and development of anti-retinal antibodies. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:723-726.].

Outer retina changes on optical coherence tomography in vitamin A deficiency

Background

Vitamin A deficiency is rare in the United States and can be missed in patients with malabsorption syndromes without a high dose of suspicion. Ocular complications of hypovitaminosis A include xerosis and nyctalopia, and to a lesser extent reduction in visual acuity and color vision. Outer retinal changes, as seen on spectral domain optic coherence tomography (SD-OCT), in patients with vitamin A deficiency have previously not been documented.

Case presentation

We present two cases with symptoms of severe nyctalopia who were subsequently diagnosed with severe Vitamin A deficiency and their unique findings on SD-OCT of outer nuclear layer diffuse thinning with irregular appearance of the interdigitating zone and the ellipsoid zone as well as normalization after vitamin A supplementation.

Conclusions

Outer nuclear layer thinning and disruption of the outer retinal bands on SD-OCT are reversible with correction of vitamin A deficiency. Improvement in visual acuity, color vision, and nyctalopia are possible with early diagnosis and appropriate treatment.

Pharmacotherapy for metabolic and cellular stress in degenerative retinal diseases

Retinal photoreceptors continually endure stresses associated with prolonged light exposure and the metabolic demands of dark adaptation. Although healthy photoreceptors are able to withstand these stresses for several decades, the disease-affected retina functions at a reduced capacity and is at an increased risk for dysfunction. To alleviate cellular and metabolic stressors in degenerative retinal diseases, a new class of drugs that modulate the metabolic activity of the retina have been developed. A clinical candidate in this class (emixustat) has been shown to reduce retinal pathology in various animal models of human retinal disease and is currently under clinical study. Here, we describe the pharmacological properties of emixustat, its mechanisms of action, and potential for use in the treatment of specific retinal diseases.

Late-onset night blindness with peripheral flecks accompanied by progressive trickle-like macular degeneration

PURPOSE

To report the clinical and genetic characteristics of 6 cases with late-onset night blindness with peripheral flecks accompanied by progressive trickle-like macular degeneration.

METHODS

Clinical and genetic data were collected from 6 independent patients who complained of night blindness in their fifth to eighth decade of life. The ophthalmological examinations included ophthalmoscopy, fundus autofluorescence (FAF), and full-field electroretinography (ERG). Whole exome sequencing with target gene analysis was performed to determine the causative genes and variants.

RESULTS

All of the patients first complained of night blindness at the ages of 40-71 years. Funduscopic examinations demonstrated white or atrophic flecks scattered in the posterior pole and peripheral retina bilaterally. FAF showed patchy hypo-autofluorescence spots in the posterior pole similar to that of the trickling type of age-related macular degeneration (AMD). The region of abnormal FAF rapidly expanded with age, and one eye developed a choroidal neovascularization. The full-field scotopic ERGs with 20 min of dark adaptation were severely reduced or extinguished in all cases. There was partial recovery of the ERGs after 180 min of dark adaptation. The cone ERGs were reduced in all cases. Whole exome sequencing revealed no pathogenic variants of 301 retinal disease-associated genes.

CONCLUSIONS

The six cases had some common features with the flecked retina syndrome, familial drusen, and late-onset retinal degeneration although none had pathogenic variants causative for these disorders. These cases may represent a subset of severe trickling AMD or a new clinical entity of acquired pan-retinal visual cycle deficiency of unknown etiology.

Soft Drusen in Age-Related Macular Degeneration: Biology and Targeting Via the Oil Spill Strategies

AMD is a major cause of legal blindness in older adults approachable through multidisciplinary research involving human tissues and patients. AMD is a vascular-metabolic-inflammatory disease, in which two sets of extracellular deposits, soft drusen/basal linear deposit (BLinD) and subretinal drusenoid deposit (SDD), confer risk for end-stages of atrophy and neovascularization. Understanding how deposits form can lead to insights for new preventions and therapy. The topographic correspondence of BLinD and SDD with cones and rods, respectively, suggest newly realized exchange pathways among outer retinal cells and across Bruch's membrane and the subretinal space, in service of highly evolved, eye-specific physiology. This review focuses on soft drusen/BLinD, summarizing evidence that a major ultrastructural component is large apolipoprotein B,E-containing, cholesterol-rich lipoproteins secreted by the retinal pigment epithelium (RPE) that offload unneeded lipids of dietary and outer segment origin to create an atherosclerosis-like progression in the subRPE-basal lamina space. Clinical observations and an RPE cell culture system combine to suggest that soft drusen/BLinD form when secretions of functional RPE back up in the subRPE-basal lamina space by impaired egress across aged Bruch's membrane-choriocapillary endothelium. The soft drusen lifecycle includes growth, anterior migration of RPE atop drusen, then collapse, and atrophy. Proof-of-concept studies in humans and animal models suggest that targeting the “Oil Spill in Bruch's membrane” offers promise of treating a process in early AMD that underlies progression to both end-stages. A companion article addresses the antecedents of soft drusen within the biology of the macula.

Novel clinical findings in autosomal recessive NR2E3-related retinal dystrophy

PURPOSE

To evaluate the clinical phenotype of autosomal recessive NR2E3-related retinal dystrophy.

METHODS

We retrospectively studied 11 patients carrying out at least 2 NR2E3 mutations; they had undergone comprehensive ophthalmological examination, fundus photography, optical coherence tomography, electrophysiological testing, and visual field at the Regional Reference Center for Hereditary Retinal Degenerations of the Eye Clinic in Florence.

RESULTS

Five females and six males with a diagnosis of NR2E3-related retinal dystrophy were included in the study. All patients complained of nyctalopia. Visual acuity ranged from 0.00 logMAR to hand motion. Two patients presented bull's eye maculopathy, and one of these was characterized by a triple hyper-autofluorescent ring at the fundus autofluorescence examination. Three patients showed small yellowish dots and spots at the mid-periphery. One patient was characterized by widespread subretinal drusenoid deposits (SDD) at the posterior pole. Four patients showed vitreous abnormalities. Optical coherence tomography (OCT) examinations detected variable degrees of abnormal retinal lamination and schitic changes. Seven patients were compound heterozygous and four were homozygous for mutations in NR2E3.

CONCLUSIONS

Our study confirmed high variable phenotype in autosomal recessive NR2E3-related retinal dystrophy. Bull's eye maculopathy, subretinal drusenoid deposits, and foveal hypoplasia represent novel clinical findings in NR2E3-related retinal dystrophy. Macular involvement was detectable in all the patients, and the abnormal foveal avascular zone (FAZ) supports the role of NR2E3 in retinal development.

IMPROVING THE AGE-RELATED MACULAR DEGENERATION CONSTRUCT: A New Classification System

Previous models of disease in age-related macular degeneration (AMD) were incomplete in that they did not encompass subretinal drusenoid deposits (pseudodrusen), subtypes of neovascularization, and polypoidal choroidal vasculopathy. In addition, Type 3 neovascularization starts in the retina and may not necessarily involve the choroid. As such, the term choroidal neovascularization is not appropriate for these eyes. The new aspects in the AMD construct are to include specific lipoprotein extracellular accumulations, namely drusen and subretinal drusenoid deposits, as early AMD. The deposition of specific types of deposit seems to be highly correlated with choroidal thickness and topographical location in the macula. Late AMD includes macular neovascularization or atrophy. The particular type of extracellular deposit is predictive of the future course of the patient. For example, eyes with subretinal drusenoid deposits have a propensity to develop outer retinal atrophy, complete outer retinal and retinal pigment epithelial atrophy, or Type 3 neovascularization as specific forms of late AMD. Given Type 3 neovascularization may never involve the choroid, the term macular neovascularization is suggested for the entire spectrum of neovascular disease in AMD. In contrast to older classification systems, the proposed system encompasses the relevant presentations of disease and more precisely predicts the future course of the patient. In doing so, the concept was developed that there may be genetic risk alleles, which are not necessarily the same alleles that influence disease expression.

Subretinal drusenoid deposits AKA pseudodrusen

A distinction between conventional drusen and pseudodrusen was first made in 1990, and more recently knowledge of pseudodrusen, more accurately called subretinal drusenoid deposits (SDDs), has expanded. Pseudodrusen have a bluish-white appearance by biomicroscopy and color fundus photography. Using optical coherence tomography, pseudodrusen were found to be accumulations of material internal to the retinal pigment epithelium that could extend internally through the ellipsoid zone. These deposits are more commonly seen in older eyes with thinner choroids. Histologic evaluation of these deposits revealed aggregations of material in the subretinal space between photoreceptors and retinal pigment epithelium. SDDs contain some proteins in common with soft drusen but differ in lipid composition. Many studies reported that SDDs are strong independent risk factors for late age-related macular degeneration. Geographic atrophy and type 3 neovascularization are particularly associated with SDD. Unlike conventional drusen, eyes with SDD show slow dark adaptation and poor contrast sensitivity. Outer retinal atrophy develops in eyes with regression of SDD, a newly recognized form of late age-related macular degeneration. Advances in imaging technology have enabled many insights into this condition, including associated photoreceptor, retinal pigment epithelium, and underlying choroidal changes.

Spotlight on reticular pseudodrusen

Age-related macular degeneration (AMD) is a leading cause of vision loss in patients >50 years old. The hallmark of the disease is represented by the accumulation of extracellular material between retinal pigment epithelium and the inner collagenous layer of Bruch's membrane, called drusen. Although identified almost 30 years ago, reticular pseudodrusen (RPD) have been recently recognized as a distinctive phenotype. Unlike drusen, they are located in the subretinal space. RPD are strongly associated with late AMD, especially geographic atrophy, type 2 and 3 choroidal neovascularization, which, in turn, are less common in typical AMD. RPD identification is not straightforward at fundus examination, and their identification should employ at least 2 different imaging modalities. In this narrative review, we embrace all aspects of RPD, including history, epidemiology, histology, imaging, functional test, natural history and therapy.

LONGITUDINAL STRUCTURAL CHANGES IN LATE-ONSET RETINAL DEGENERATION

PURPOSE

To characterize longitudinal structural changes in early stages of late-onset retinal degeneration to investigate pathogenic mechanisms.

METHODS

Two affected siblings, both with a S163R missense mutation in the causative gene C1QTNF5, were followed for 8+ years. Color fundus photos, fundus autofluorescence images, near-infrared reflectance fundus images, and spectral domain optical coherence tomography scans were acquired during follow-up.

RESULTS

Both patients, aged 45 and 50 years, had good visual acuities (>20/20) in the context of prolonged dark adaptation. Baseline color fundus photography demonstrated yellow-white, punctate lesions in the temporal macula that correlated with a reticular pattern on fundus autofluorescence and near-infrared reflectance imaging. Baseline spectral domain optical coherence tomography imaging revealed subretinal deposits that resemble reticular pseudodrusen described in age-related macular degeneration. During follow-up, these affected areas developed confluent thickening of the retinal pigment epithelial layer and disruption of the ellipsoid zone of photoreceptors before progressing to overt retinal pigment epithelium and outer retinal atrophy.

CONCLUSION

Structural changes in early stages of late-onset retinal degeneration, revealed by multimodal imaging, resemble those of reticular pseudodrusen observed in age-related macular degeneration and other retinal diseases. Longitudinal follow-up of these lesions helps elucidate their progression to frank atrophy and may lend insight into the pathogenic mechanisms underlying diverse retinal degenerations.

MULTIPLE EVANESCENT WHITE DOT SYNDROME WITH SUBRETINAL DEPOSITS

PURPOSE

To describe the multimodal imaging findings of transient subretinal deposits occurring in multiple evanescent white dot syndrome (MEWDS).

METHODS

The multimodal imaging characteristics of transient subretinal deposits occurring in MEWDS were investigated with ultra-widefield color and fundus autofluorescence, cross-sectional and en-face optical coherence tomography (OCT), en face OCT-angiography, and quantitative autofluorescence.

RESULTS

A 28-year-old woman presented with photopsia and temporal visual field loss in her right eye. Her best-corrected visual acuity was 20/20 in her right eye and 20/25 in her left eye. Funduscopic examination showed characteristic peripapillary hyperautofluorescent white dots of MEWDS corresponding to ellipsoid zone disruption on OCT. These lesions became confluent throughout the posterior fundus over the next 4 weeks. As the patient's symptoms were resolving, a second type of transient hyperautofluorescent lesion was noted which corresponded to hyperreflective subretinal deposits on cross-sectional and en face structural OCT. These subretinal deposits were most evident at 10-week follow-up and had nearly resolved at 14-week follow-up. Quantitative autofluorescence showed that, unlike the acute MEWDS lesions, the hyperautoflurescence of the subretinal deposits persisted after photobleaching. At multiple time points over 14 weeks of follow-up, OCT angiography showed no evidence of retinal or choroidal flow abnormalities.

CONCLUSION

Transient subretinal deposits may develop during MEWDS in areas of previous diffuse outer retinal disruption. As these deposits remain hyperautoflurescent on quantitative autofluorescence after photobleaching, they may represent accumulations of debris originating from damaged photoreceptor outer segments.

Coronary Artery Disease and Reticular Macular Disease, a Subphenotype of Early Age-Related Macular Degeneration

PURPOSE

Reticular macular disease (RMD) is the highest risk form of early age-related macular degeneration and also specifically confers decreased longevity. However, because RMD requires advanced retinal imaging for adequate detection of its characteristic subretinal drusenoid deposits (SDD), it has not yet been completely studied with respect to coronary artery disease (CAD), the leading cause of death in the developed world. Because CAD appears in middle age, our purpose was to screen patients aged 45-80 years, documented either with or without CAD, to determine if CAD is associated with RMD.

DESIGN

A prospective cohort study of patients with documented CAD status and no known retinal disease in a clinical practice setting at one institution. Subjects and Controls: A number of 76 eyes from 38 consecutive patients (23 with documented CAD, 15 controls documented without CAD; 47.4% female; mean age 66.7 years).

METHODS

Patients were imaged with near-infrared reflectance/spectral domain optical coherence tomography and assessed in masked fashion by two graders for the presence of SDD lesions of RMD and soft drusen.

MAIN OUTCOME MEASURES

Presence or absence of RMD/SDD and soft drusen.

RESULTS

RMD was more frequent in patients with CAD versus those without (Relative Risk [RR] = 2.1, CI = 1.08-3.95, P = 0.03). There was no association of CAD with soft drusen.

CONCLUSIONS

A specific relationship between CAD and RMD suggests common systemic causes for both and warrants further study.

Treatment of vitamin A deficiency retinopathy with sublingual vitamin A palmitate

PURPOSE

To report treatment of vitamin A deficiency retinopathy with sublingual vitamin A drops.

METHODS

Case report with review of the literature.

RESULTS

A 69-year-old Caucasian woman with a history of small bowel resection presented with progressive symptoms of bilateral nyctalopia and decreased visual acuity. Ophthalmic examination revealed bilateral conjunctival xerosis and fine white granular deposits in the midperipheral retina suggestive of vitamin A deficiency. Full-field electroretinogram (ERG), multifocal ERG (mfERG), and two-color dark adaptometry revealed significant impairment of rod and cone photoreceptor function. Kinetic perimetry demonstrated depressed macular sensitivity with constriction of the finer isopters. After 5 months of treatment with sublingual vitamin A drops, the patient's vision, ERG, mfERG, dark adaptometry, and perimetry normalized. A review of the literature summarizing the electrophysiologic testing in vitamin A deficiency is also discussed.

CONCLUSIONS

This case highlights novel observations on the effects of sublingual vitamin A supplementation for acquired vitamin A deficiency retinopathy. Sublingual vitamin A may represent a viable and efficacious treatment modality for vitamin A deficiency.

Prevalence of Subretinal Drusenoid Deposits in Older Persons with and without Age-Related Macular Degeneration, by Multimodal Imaging

PURPOSE

To assess the prevalence of subretinal drusenoid deposits (SDD) in older adults with healthy maculas and early and intermediate age-related macular degeneration (AMD) using multimodal imaging.

DESIGN

Cross-sectional study.

PARTICIPANTS

A total of 651 subjects aged ≥60 years enrolled in the Alabama Study of Early Age-Related Macular Degeneration from primary care ophthalmology clinics.

METHODS

Subjects were imaged using spectral domain optical coherence tomography (SD OCT) of the macula and optic nerve head (ONH), infrared reflectance, fundus autofluorescence, and color fundus photographs (CFP). Eyes were assessed for AMD presence and severity using the Age-Related Eye Disease Study (AREDS) 9-step scale. Criteria for SDD presence were identification on ≥1 en face modality plus SD OCT or on ≥2 en face modalities if absent on SD OCT. Subretinal drusenoid deposits were considered present at the person level if present in 1 or both eyes.

MAIN OUTCOME MEASURES

Prevalence of SDD in participants with and without AMD.

RESULTS

Overall prevalence of SDD was 32% (197/611), with 62% (122/197) affected in both eyes. Persons with SDD were older than those without SDD (70.6 vs. 68.7 years, P = 0.0002). Prevalence of SDD was 23% in subjects without AMD and 52% in subjects with AMD (P < 0.0001). Among those with early and intermediate AMD, SDD prevalence was 49% and 79%, respectively. After age adjustment, those with SDD were 3.4 times more likely to have AMD than those without SDD (95% confidence interval, 2.3-4.9). By using CFP only for SDD detection per the AREDS protocol, prevalence of SDD was 2% (12/610). Of persons with SDD detected by SD OCT and confirmed by at least 1 en face modality, 47% (89/190) were detected exclusively on the ONH SD OCT volume.

CONCLUSIONS

Subretinal drusenoid deposits are present in approximately one quarter of older adults with healthy maculae and in more than half of persons with early to intermediate AMD, even by stringent criteria. The prevalence of SDD is strongly associated with AMD presence and severity and increases with age, and its retinal topography including peripapillary involvement resembles that of rod photoreceptors. Consensus on SDD detection methods is recommended to advance our knowledge of this lesion and its clinical and biologic significance.

Optical Coherence Tomography Assessment Before and After Vitamin Supplementation in a Patient With Vitamin A Deficiency: A Case Report and Literature Review

Vitamin A is an essential fat-soluble vitamin important for the function of various body systems. In the eye, vitamin A is essential for the synthesis of visual pigments in photoreceptors. Vitamin A deficiency is a rare condition in the developed countries and might follow bariatric or intestinal bypass surgery.We present the case of a 67-year-old male that complained of visual loss and nyctalopia. Patient had bariatric surgery 15 years before for weight loss. Low serum levels of vitamin A confirmed the diagnosis and patient started vitamin A supplementation. Visual fields, macular thickness, and ganglion cell layer thickness were recorded and monitored 1 month, 6 months, and 1 year after the beginning of therapy. Visual fields were significantly altered and central macular thickness and ganglion cell layer thickness were reduced, but the first 2 showed a significant recovery with vitamin supplementation therapy. By the 1st month of treatment patient referred a complete remission of visual symptoms. Further, we observed hyperreflective material accumulating beneath a partially disrupted ellipsoid band in the high definition optical coherence tomography that also improved progressively with vitamin repletion.Newer and more sophisticated imaging systems have increased our knowledge of the mechanisms responsible for retinal diseases. To our knowledge, this is the first description of the effect of vitamin A deficiency and vitamin supplementation on macular thickness. This case also highlights the importance of considering bariatric bypass surgery as a cause of vitamin A deficiency in developed countries.

Association of age-related macular degeneration and reticular macular disease with cardiovascular disease

Age-related macular degeneration is the leading cause of adult blindness in the developed world. Thus, major endeavors to understand the risk factors and pathogenesis of this disease have been undertaken. Reticular macular disease is a proposed subtype of age-related macular degeneration correlating histologically with subretinal drusenoid deposits located between the retinal pigment epithelium and the inner segment ellipsoid zone. Reticular lesions are more prevalent in females and in older age groups and are associated with a higher mortality rate. Risk factors for developing age-related macular degeneration include hypertension, smoking, and angina. Several genes related to increased risk for age-related macular degeneration and reticular macular disease are also associated with cardiovascular disease. Better understanding of the clinical and genetic risk factors for age-related macular degeneration and reticular macular disease has led to the hypothesis that these eye diseases are systemic. A systemic origin may help to explain why reticular disease is diagnosed more frequently in females as males suffer cardiovascular mortality at an earlier age, before the age of diagnosis of reticular macular disease and age-related macular degeneration.