Retinal Crystals Research Articles

Embolismos retinianos por colesterol tras angiografía coronaria

We report a patient with multiple cholesterol retinal embolism in both eyes following coronary angiography. She also had associated renal, skin and cardiac manifestations of the Cholesterol Embolization Syndrome (CES) and died 10 weeks later. Autopsy revealed cholesterol crystal emboli in several organs. Atheromatous plaques can be ruptured and displaced during a diagnostic catheterisation, and thus can be a potential source of these massive emboli. Retinal cholesterol crystals help to establish the diagnosis of the syndrome, particularly when other systemic manifestations exist. When this complication occurs, the prognosis can be devastating because of associated multiorgan failure.

Refractile superficial retinal crystals and chronic retinal detachment: Case report

BackgroundFew previous reports have described the presence of retinal refractile opacities at the macular area in patients presenting with longstanding peripheral retinal detachment. The exact nature of these opacities is unknown.Case presentationTwo patients were referred with an abnormal appearance of refractile opacities in the macular area noted during routine examination. Both were found to have longstanding peripheral retinal detachments. Subretinal fluid analysis of one patient revealed the presence of multiple birefringent crystals. We hypothesise that these crystals are the origin of the refractile macular opacities noted.ConclusionThis report describes the rare presentation of asymptomatic peripheral retinal detachment by the detection of refractile macular opacities on routine examination. It highlights the importance of meticulous peripheral retinal examination in these cases. The article also describes the findings of the subretinal fluid analysis and discusses the possible hypothesis behind their appearance.

Intraocular Crystals in HIV-Related Hypergammaglobulinemia

Purpose: To describe the occurrence of bilateral iris and retinal crystals in a patient with benign HIV-related gammopathy. Design: Observational case report. Methods: A 45-year-old HIV-positive male with a known, benign hypergammaglobulinemia was referred for routine ophthalmic assessment because of right ophthalmic zoster. Results: Ophthalmoscopic examination revealed the presence of bilateral, multiple, refractile iris and macular crystals. No other signs of uveitis or stigmata of HIV were found. Conclusion: Intraocular crystals are a rare finding, usually seen in chronic uveitis with or without hypergammaglobulinemia. This finding has not been previously described in non-inflamed eyes, nor as an ocular manifestation of HIV. We hypothesize that HIV-related disruption of the blood-aqueous and blood-retinal barriers allows intraocular immunoglobulin deposition in patients with hypergammaglobulinemia.

West African crystalline maculopathy

Objective To report new observations in West African crystalline maculopathy. Design Retrospective, observational case series. Participants Three patients drawn from a private retina practice. Methods Review of clinical charts and photographic studies. Main outcome measures Distribution of intraretinal crystals and changes after laser photocoagulation, and history of ingesting foods typical in a West African diet but atypical for an American diet. Results All patients were older than 50 years, had diabetic retinopathy, ate green vegetables not found in American diets, and showed no deleterious effects of the crystals. Kola nut ingestion in 2 patients was remote and sparse, and was unknown in a third patient. The first 2 affected patients originating outside the Ibo tribe of Nigeria are reported. The pattern of retinal crystals can be changed, and the quantity of crystals reduced, by laser photocoagulation of associated diabetic retinopathy. Conclusions West African crystalline retinopathy is distinguishable from other causes of crystalline retinopathy. It may reflect a component of the West African diet, seems to have diabetic retinopathy as a promoting factor via breakdown of the blood–retina barrier, and can be modified by laser photocoagulation of diabetic retinopathy. Increased awareness of the condition will allow physicians seeing West African immigrants to make the diagnosis and treat the patients appropriately.

The differential diagnosis of crystals in the retina.

Crystalline deposits in the retina may be associated with a wide variety of systemic disorders such as oxalosis, cystinosis, hyperornithinaemia and Sjögren-Larsson syndrome. Refractile crystalline deposits may also be a manifestation of drug toxicity like the antineoplastic agent tamoxifen, the anesthetic methoxyflurane and the oral tanning agent canthaxanthine. Crystals may also occur in drug abusers who inject multiple crushed tablets of methadone or meperidine intravenously (talc retinopathy). The differential diagnosis of retinal crystals also includes primary ocular diseases like Bietti's crystalline retinopathy, calcified macular drusen, idiopathic parafoveal telangiectasis and longstanding retinal detachment. This article will review the most common causes of crystalline retinopathies, their etiologies, pathologies and clinical characteristics.

Bilateral idiopathic juxtafoveolar retinal telangiectasis

Bilateral idiopathic juxtafoveolar retinal telangiectasis (JRT) is a condition of unknown etiology characterized by telangiectatic retinal vessels located temporal to the fovea. Most patients with bilateral JRT have associated telangiectasis, dilated capillaries, minimal exudation, retinal crystals, right angle venules, and retinal pigment hyperplasia. An unusual case of bilateral retinal telangiectasis with associated asymmetric cystoid macular edema in a middle-aged female is presented. This case is unusual due to the presence of cystoid macular edema. Classification, differential diagnosis and management of idiopathic juxtafoveolar retinal telangiectasis are reviewed.

Tamoxifen-associated eye disease. A review.

The oral antiestrogen tamoxifen has demonstrated efficacy in the treatment of metastatic breast cancer and as adjuvant therapy in early-stage disease. Clinical trials of tamoxifen in chemoprevention of breast cancer among high-risk women have focused attention on potential adverse effects of long-term tamoxifen use, including the possibility of ocular toxicity. This review evaluates the published case reports, clinical series, and clinical trial data on ocular toxicities attributed to tamoxifen. Clinical issues of surveillance, differential diagnosis, and management of tamoxifen-related eye disease are discussed. National Library of Medicine online bibliographic services were used to identify case reports and clinical studies of ocular adverse effects that occurred in patients receiving tamoxifen published through the fall of 1994. The medical literature relevant to issues raised by the reports and studies was similarly identified and reviewed. Case reports and case series identify crystalline retinal deposits, macular edema, and corneal changes as potential tamoxifen ocular toxicities. Extensive retinal lesions and macular edema with visual impairment have been reported in a few patients receiving high-dose tamoxifen. Less extensive retinal changes may occur in patients receiving low doses for long periods, and isolated retinal crystals may be observed in patients without visual symptoms. Ocular toxicity is uncommon in the current clinical setting of long-term, low-dose tamoxifen use. Physicians should be aware of the potential for ocular toxicity among patients receiving the drug and should assure appropriate surveillance and prompt evaluation of visual complaints.

Gastrointestinal Blood Loss Due to Cholesterol Crystal Embolization

Gastrointestinal blood loss in elderly atherosclerotic patients may be due to cholesterol crystal embolization (CCE) leading to ischemic lesions in the gastrointestinal tract. The diagnosis of CCE is favored by accompanying clinical or biochemical signs, such as blue toes, renal insufficiency, and eosinophilia. Our report describes the clinical data of four patients with gastrointestinal blood loss due to CCE. In two the bleeding source was in the duodenum, and in the other two the source was in the distal colon. The diagnosis was made by histological examination of endoscopic biopsies in three and of a sigmoid resection specimen in one. Provoking factors were anticoagulant therapy in one, anticoagulant therapy and aortography in another, and aortography followed by aorta bifurcation prosthesis implantation in the third, whereas no provoking factor could be identified in the remaining patient. Accompanying signs included eosinophilia in one, a blue toe with renal insufficiency in one, and retinal cholesterol crystals in another patient. Our findings, in line with previous reports, highlight the importance of CCE in the differential diagnosis of gastrointestinal blood loss in elderly patients.

Canthaxanthin retinopathy. Follow-up of over 6 years

After long-term treatment with high dosages, canthaxanthin causes a characteristic retinopathy with circular, macula surrounding crystals. As changes in retinal functionning disappear relatively easily after withdrawal of the drug, the crystals dissolve rather slowly--over about several years. Five patients showing a profound crystalline retinopathy were re-examined with an average of 69.7 months after withdrawal of the canthaxanthin-containing drug. Three of the patients were treated for erythropoetic protoporphyria (EPP) with Phenoro (2/5 beta-carotene, 3/5 canthaxanthin), two sisters took a canthaxanthin-containing formulation (1/8 beta-carotene, 7/8 canthaxanthin) for cosmetic reasons. Two female patients complained about an increased glare sensitivity, which was explainable for one of them with a subcapsular cataract. The retinal crystals decreased quite differently. Minor deffects of the retinal pigment epithelium remained unchanged in two patients. They increased slightly in the female patient with the smallest crystal formation but highest plasma cholesterol. Shortly after withdrawal of the drugs usually an increase of a-wave amplituded of the electroretinograms was found. The a-waves returned to normal and the b-wave amplitudes showed an increase up to the final control paralleling the reduction of the retinal crystals. A- and b-wave peak latencies which were prolonged under treatment returned to normal.

BIETTIʼS CORNEAL-RETINAL DYSTROPHY

Bietti's crystalline corneal-retinal dystrophy is characterized by deposits of crystals in the marginal cornea and the paracentral and peripapillary retina. To date, only three cases with long term follow-up have been reported. The case of another patient, who has been observed for 16 years, is reported here. The most striking morphologic feature during the period of examination was the diminution of the retinal crystals, an optical phenomenon that appears to be due to the advanced atrophy of the retinal pigment epithelium. The progressive course is documented photographically.

Absence of Retinal Crystals in High-Dosage Beta-Carotene Administration

AbstractPatients with erythropoietic protoporphyria (EPP) are photosensitive to short-wavelength solar exposure due to the endogenous presence of pro-toporphyrin in their tissues. Treatment has involved administration of high dosages of carotenoids, which are considered to protect the patient by quenching singlet oxygen and scavenging photically generated free radical species within the skin. β-Carotene and canthaxanthin have been used in Europe as a mixture in the treatment of EPP and have been associated with the presence of golden crystals in the retinae of some patients. However, the production of crystals has been attributed only to canthaxanthin.In this study, 13 patients with EPP, treated in the United States only with β-carotene, were examined for the presence of crystals. None were found, even though several patients had taken large lifetime doses of up to 821.52 g for periods of up to 19 years. This report presents the β-carotene dosage, blood levels, and retinal findings from these patients.

Monitoring of Patients taking Canthaxanthin and Carotene: An Electroretinographic and Ophthalmological Survey

1. Patients who have taken canthaxanthin and beta-carotene to avert phototoxicity have been monitored by electroretinographic testing. 2. Patients took the compounds only during the summer months, but were monitored for more than 1 year to determine if seasonal changes in the ERG were visible. 3. The characteristic refractile retinal crystals reduced during the winter. 4. The scotopic b-wave amplitude increased during the winter, whether evoked by red or blue flashes. 5. No other ERG parameter altered. 6. Changes noted in 3 and 4 above are reversible. 7. A dose/ERG-amplitude response relationship was established, but no correlation between blood level or total cumulative dose and b-wave amplitude could be found. 8. It is suggested that the Müller cells concentrate canthaxanthin and this is the mechanism which affects the ERG.

Carotinoid retinopathy. II. Electrophysiologic findings in 23 carotenoid-treated patients

Twenty-three patients on long-term therapy (up to 14 years) with carotenoids (up to 336 g) were tested electrophysiologically. The EOG revealed a small but not significant delay of the light peak. Arden's ratio, however, was normal. The ERG was depressed as far as photopic activity was concerned. At low dosages of carotenoids the scotopic ERG amplitudes were found to be hypernormal, whereas at higher dosages the increase in amplitude during dark-adaptation was markedly delayed. There was a dose-dependent prolongation of b-wave implicit time and a dose-dependent reduction in oscillatory potentials. The marked effect on the b-wave and on the oscillatory potentials and the site of the retinal crystals permit the assumption that a mechanism of carotenoid action is located in the middle layers of the retina.

Carotenoid retinopathy. I. Morphologic and functional findings

Thirty patients who had undergone long-term treatment with carotenoids (max. 14 years and 336 g of carotenoids) were examined. Ophthalmoscopy revealed retinal crystals in 20 patients. The retinal crystals were usually located around the macula, forming a ring, and in one case they were even found in the macula itself. No deterioration of visual acuity or visual field defects were found, but there was a markedly dose-dependent prolongation of the duration of dark adaptation.

Central areolar choroidal dystrophy with retinal crystals

Central choroidal dystrophy is characterized by lack of large parts of the central choroid. In the dystrophic region outer retinal layers are also involved whereas inner retinal layers may be unaffected. Three patients with central choroidal dystrophy and retinal crystals in the dystrophic region or near its border are described. Predominantly, these crystals are located in the inner or middle retinal layers. The amplitude of the electroretinogram is reduced according to the extent of the defect in the neurosensory epithelium. In the cases described here the inner retinal layers may also be involved in the pathologic process. In two patients with the most marked clinical and electrophysiological disturbances, a multiple lipoprotein-type hyerlipidemia was found.

Central chorioretinal dystrophy with drusen and retinal crystals

4 patients out of 2 pedigrees present an association of dominant drusen, central chorioretinal dystrophy and retinal crystals. It seems to be transmitted in an autosomal dominant mode. Drusen have also been found in 4 patients (3rd generation) at the age of 40 years. Central chorioretinal dystrophy and retinal crystals have not been found prior to the age of 60 years. Visual acuity and central scotoma depend on the central chorioretinal dystrophy. Electro-oculograms and electroretinograms exhibited relatively little changes. 2 patients showed phenotype II and IV of Fredriksen.