The differential diagnosis of crystals in the retina

In vivo deposition of poorly soluble drugs

Administered drug molecules, whether dissolved or solubilized, have the potential to precipitate and accumulate as solid forms in tissues and cells within the body. This phase transition can significantly impact the pharmacokinetics of treatment. It is thus crucial to gain an understanding of how drug solubility/permeability, drug formulations and routes of administration affect in vivo behaviors of drug deposition. This review examines literature reports on the drug deposition in tissues and cells of poorly water-soluble drugs, as well as underlying physical mechanisms that lead to precipitation. Our work particularly highlights drug deposition in macrophages and the subcellular fate of precipitated drugs. We also propose a tissue permeability-based classification framework to evaluate precipitation potentials of poorly soluble drugs in major organs and tissues. The impact on pharmacokinetics is further discussed and needs to be considered in developing drug delivery systems. Finally, bioimaging techniques that are used to examine aggregated states and the intracellular trafficking of absorbed drugs are summarized.

Tamoxifen retinopathy: A comprehensive review

Tamoxifen is a selective estrogen receptor modulator used mainly for the treatment of breast cancer. Based on the case reports and studies performed to date on the retinal toxicity of tamoxifen, retinopathy appears to occur in as many as 12% of patients taking 20 mg tamoxifen a day for over 2 years. Of this 12%, as many as half develop symptomatic changes in visual acuity. Retinal changes consist primarily of crystalline deposits, cystoid macular edema, hyperreflective deposits in the inner retinal layers, and telangiectasia. Tamoxifen retinopathy is currently managed by discontinuing tamoxifen therapy as the cancer prognosis permits; however, discontinuing therapy demonstrates little to no improvement in visual acuity once visual changes have taken place. Intravitreal injections of steroids or antivascular endothelial growth factor therapy have been performed, but require further studying before conclusions can be made. Until then, optical coherence tomography screening for retinal changes should be performed every 6 months for patients who have been on tamoxifen therapy for 2 years or more. This way, patients can become aware of retinal changes, and their physicians can consider adjusting tamoxifen therapy before they risk developing changes in visual acuity.

RETINAL DEPOSITS OF TRIAMCINOLONE-MOXIFLOXACIN AFTER DROPLESS CATARACT SURGERY

PURPOSE

To report a case of epiretinal crystalline deposits observed on fundus examination and optical coherence tomography 2 years after transzonular intravitreal injection of triamcinolone-moxifloxacin (TriMoxi) during "dropless" cataract surgery.

METHODS

Observational case report with literature review of toxic effects of intravitreal triamcinolone and differential diagnosis of retinal crystalline deposits.

RESULTS

A 37-year-old asymptomatic pseudophakic man presented with refractile crystalline retinal deposits that had prompted an extensive systemic embolic workup. The systemic evaluation for emboli was negative. OCT imaging revealed that the crystalline deposits were confined to the anterior surface of the internal limiting membrane. Further historical inquiry determined that transzonular intravitreal triamcinolone-moxifloxacin injection had been performed at the time of cataract surgery 2 years earlier.

CONCLUSION

Transzonular triamcinolone acetonide delivered during cataract surgery can deposit on the retinal surface for long periods. These epiretinal crystalline deposits are benign and generally do not interfere with visual acuity. Nevertheless, clinicians should be aware of this differential diagnosis because clinical misdiagnosis can lead to unwarranted evaluation and treatment.

A case of Bietti crystalline dystrophy with clinical, electrophysiological, and imaging findings

In this study, ophthalmologic examination findings, fundus fluorescein angiography, optic coherence tomography (OCT), visual field testing, electrophysiological, and systemic laboratory findings of a 43-year-old female patient who presented with blurry vision and who had retinal and corneal deposits were examined. Our patients’ best-corrected visual acuity was 0.9 bilaterally. Her anterior segments and intraocular pressures were bilaterally normal. Fundus examination revealed bilateral glistening yellowish intraretinal crystalline deposits in the posterior pole and midperipheral retina. The electroretinographic examination revealed a decrease in scotopic and photopic a and b wave amplitudes. Corneal and intraretinal glistening crystalloid deposits were observed in the OCT. Our patient and her husband were relatives. Her sister’s, brother’s, and children’s OCT also revealed bilateral corneal and intraretinal crystalloid deposits. We diagnosed this case as Bietti’s crystalline dystrophy which is a rare disease with genetic inheritance that must be considered in the differential diagnosis in countries in which consanguineous marriage is often.

Multiorgan Crystal Deposition of an Amphoteric Drug in Rats Due to Lysosomal Accumulation and Conversion to a Poorly Soluble Hydrochloride Salt

Poor solubility of drug candidates mainly affects bioavailability, but poor solubility of drugs and metabolites can also lead to precipitation within tissues, particularly when high doses are tested. RO0728617 is an amphoteric compound bearing basic and acidic moieties that has previously demonstrated good solubility at physiological pH but underwent widespread crystal deposition in multiple tissues in rat toxicity studies. The aim of our investigation was to better characterize these findings and their underlying mechanism(s), and to identify possible screening methods in the drug development process. Main microscopic features observed in rat RO0728617 toxicity studies were extensive infiltrates of crystal-containing macrophages in multiple organs. Matrix-assisted laser desorption/ionization Fourier transform ion cyclotron resonance mass spectrometry revealed that these crystals contained the orally administered parent compound, and locality was confirmed to be intracytoplasmic and partly intralysosomal by electron microscopic examination. Crystal formation was explained by lysosomal accumulation of the compound followed by precipitation of the hydrochloride salt under physiological conditions in the lysosomes, which have a lower pH and higher chloride concentration in comparison to the cytosol. This study demonstrates that risk of drug precipitation can be assessed by comparing the estimated lysosomal drug concentration at a given dose with the solubility of the compound at lysosomal conditions.

Novel retinal findings in β-thalassemia major: older age and higher ferritin level as the risk factors

PURPOSE

To investigate retinal changes in β-thalassemia major patients and identify their association with systemic risk factors.

METHODS

In this prospective study, 120 β-thalassemia major patients received complete ophthalmic examinations (best-corrected visual acuity, contrast sensitivity, color vision, and indirect ophthalmoscopy) and retinal imaging using color fundus photography and fundus autofluorescence imaging. Patients were grouped according to the presence of thalassemia-related retinal changes. The association between systemic risk factors (age, type and duration of iron chelator use, history of splenectomy, hemoglobin level, and ferritin level) and thalassemia-related retinal changes was investigated using logistic regression analysis.

RESULTS

Thalassemia-related retinal changes were identified in 36.7% of patients. Several distinct retinal changes were observed, including retinal refractile bodies in 10% of patients and retinal hemorrhage in 5.8% of patients. Fundus autofluorescence imaging showed abnormal patterns in 36.3% of patients with thalassemia-related retinal changes and 18.4% of patients without thalassemia-related retinal changes. Age (odds ratio [OR] = 1.10, 95% confidence interval [CI] 1.03-1.18) and ferritin level (OR 1.16, 95% CI 1.01-1.33) were associated with thalassemia-related retinal changes.

CONCLUSION

Novel retinal changes were observed in β-thalassemia major patients. This study identified older age and higher ferritin level as risk factors for thalassemia-related retinal changes.

Retinal crystalline deposits in a patient who received chemotherapy and radiotherapy for nasopharyngeal carcinoma and subsequent anti-VEGF treatment for the bilateral radiation maculopathy

We report the occurrence of intraretinal crystalline deposits in a patient who received several anti-VEGF injections and one session of focal laser treatment for the treatment of radiation retinopathy during the treatment process. She had received three cycles of epirubicin and cisplatin together with radiation therapy seven years prior to detection of the maculopathy. The multimodal imaging features and the possible cause of the retinal crystalline deposits are discussed.

CRYSTALLINE RETINOPATHY AND RETINAL VASCULOPATHY IN CALCIFIC UREMIC ARTERIOLOPATHY (CALCIPHYLAXIS)

PURPOSE

To report the posterior segment and retinal vascular manifestations of calcific uremic arteriolopathy (calciphylaxis). Clinical findings are correlated with multimodal imaging results.

METHODS

Observational case report.

RESULTS

A 65-year-old white woman on hemodialysis was referred for assessment of poor vision bilaterally. Clinical examination demonstrated a crystalline retinopathy with stigma of previous retinal arterial occlusion. Fluorescein angiography revealed delayed retinal arterial filling bilaterally, sheathing of vessels, and peripheral nonperfusion. The crystals were hyperautofluorescent. Spectral domain and enhanced depth imaging optical coherence tomography localized the crystals within the retina with a predilection for the retinal arterial vasculature. The choriocapillaris was not involved. Two years prior, the patient developed necrotic skin lesions which were biopsied and confirmed the diagnosis of calciphylaxis.

CONCLUSION

Calcific uremic arteriolopathy is an extremely rare cause of thrombogenic microangiopathy in end-stage renal disease patients. Retinal arterial occlusion appears to be a rare but significant cause of visual loss in this disease and is likely to be consequent to crystalline deposition in the retinal vasculature.

Retinal toxicity due to canthaxanthin. Case series

INTRODUCTION

Canthaxanthin is a chemical product used to tan the skin. Its most frequent adverse effect is canthaxanthin retinopathy.

PURPOSE/ METHODS

Report, case series.

RESULTS

Two female patients, one 42 years-old and the other 72 years-old, with signs of retinopathy due to canthaxanthin. Complete ophthalmology examinations were carried out. The peripheral fovea birefringent deposits with internal retinal involvement were studied using multimodal imaging.

CONCLUSION

Canthaxanthin retinopathy is rare. Multimodal imaging may provide important data for the differential diagnosis of crystalline retinopathy.

MACULAR PIGMENT DISTRIBUTION RESPONSES TO HIGH-DOSE ZEAXANTHIN SUPPLEMENTATION IN PATIENTS WITH MACULAR TELANGIECTASIA TYPE 2

PURPOSE

To analyze macular pigment (MP) amount and distribution in patients with macular telangiectasia Type 2 receiving oral zeaxanthin supplementation in a randomized, open-label, interventional trial.

METHODS

Eight macular telangiectasia Type 2 patients were randomized to 10 mg or 20 mg of zeaxanthin per day. At each visit, best-corrected visual acuity, contrast sensitivity, fundus biomicroscopy, color fundus photography, autofluorescence imaging, optical coherence tomography, and serum carotenoid levels were tested. Patients were assessed at baseline and after 6, 12, 18, and 24 months of zeaxanthin supplementation. Concentration of MP was analyzed and calculated from autofluorescence imaging obtained at 488-nm excitation wavelength. Serum carotenoid levels were obtained using high-performance liquid chromatography.

RESULTS

The majority of patients had definite increases in the intensity of hypofluorescent ring of MP, but none of them deposited MP centrally at the fovea. Although some patients noted subjective improvements in vision, no objective improvements could be documented, and there were no changes in foveal optical coherence tomographic features. Yellowish, hypofluorescent crystals appeared in one patient's macular region with no change in visual acuity. These inner retinal crystals disappeared several months after discontinuing her 20-mg zeaxanthin supplement.

CONCLUSION

Based on the current study, zeaxanthin supplementation does not result in any visual benefit in patients with macular telangiectasia Type 2 and does not reestablish a normal peaked distribution of MP in the fovea. One patient developed a novel, reversible, crystalline maculopathy in response to zeaxanthin supplementation that was reminiscent of canthaxanthin crystalline maculopathy.

TAMOXIFEN RETINOPATHY DURING TREATMENT OF AN INOPERABLE DESMOID TUMOR

PURPOSE

To evaluate the clinical significance and rarity of tamoxifen retinopathy after a long-term tamoxifen treatment for an inoperable desmoid tumor.

METHODS

Case report.

RESULTS

Tamoxifen retinopathy is a condition rarely observed in clinical practice. Although tamoxifen is typically a treatment for breast cancer patients, we present a 68-year-old woman taking tamoxifen for an inoperable desmoid tumor, an equally rare condition. She presented with bilaterally deteriorating vision over the course of a year. Fundoscopic examination revealed parafoveal deposits bilaterally. Spectral domain optical coherence tomography exhibited hyperreflective deposits in all layers of the retina. She had a cumulative treatment dose of 292 g of tamoxifen, and the medication was subsequently stopped. Her vision remained stable 3 months after the cessation of tamoxifen.

CONCLUSION

The development of tamoxifen retinopathy in the treatment of a desmoid tumor makes this case a rare entity, and this is the first reported case of these two concomitant conditions to our knowledge. With the use of long-term tamoxifen as a primary treatment, we recommend screening at regular intervals by an ophthalmologist as an integral part of treatment.

First Described Case of Anterior and Posterior Segment Crystals in Phacolytic Glaucoma

Phacolytic glaucoma is an open-angle glaucoma that occurs when lens proteins from hypermature cataracts seep through an intact anterior capsule and induce obstruction of the trabecular meshwork by inflammatory cells. We review the case of a 66-year-old man who presented with acute pain, a hypermature cataract, prominent anterior chamber crystals, and elevated intraocular pressure. After cataract surgery was performed, iridescent crystals were noted in the posterior chamber. Anterior chamber crystals have been associated with phacolytic glaucoma, but this is the first case demonstrating crystals in the posterior chamber as well.

Practical approach to syndromic pediatric retinal dystrophies

PURPOSE OF REVIEW

The purpose of this review is to outline those systemic disorders that are associated with pediatric retinal dystrophy, summarize important retinal, and nonretinal clues that aid in syndromic diagnosis, provide an approach for ophthalmic and systematic systemic examination, describe the important systemic findings seen in pediatric syndromic retinal dystrophies and highlight the role of genetic testing.

RECENT FINDINGS

With profound advances being made in the field of molecular genetics, a definitive molecular etiology is increasingly being made even in rare and unusual forms of retinal dystrophies. Early recognition and precise diagnosis of a syndromic association has major clinical implications. It not only ensures early and holistic care to the child but also provides an opportunity for the parents in better understanding the nature and course of the disorder. It greatly aids in genetic counseling.

SUMMARY

Many syndromic retinal dystrophies may present initially to the ophthalmologist long before they present to the pediatrician with systemic symptoms. The intent of this article is to act as a resource in assisting the ophthalmologist to arrive at an early systemic diagnosis.

Crystalline retinopathy association with flupentixol intake

AIM

To report the first case report of an association between flupentixol and crystalline retinopathy.

STUDY DESIGN

Observational, Case report.

CASE REPORT

We report a case of crystalline retinopathy in a 36-year-old female who was suffering from depression and being treated with tablet flupentixol in a cumulative dose of 4380 mg over two years. Fundus examination of both eyes showed multiple, discrete, yellowish white refractile intraretinal deposits over the macula and peripapillary region, located in the inner retina as shown by OCT.

CONCLUSION

We propose regular retinal evaluation in patients with chronic flupentixol intake and larger studies to establish causal relationship between flupentixol and crystalline retinopathy.

Gyrate Atrophy-Like Phenotype: Normal Plasma Ornithine and Retinal Crystals

PURPOSE

To report an unusual case of a gyrate atrophy-like presentation with retinal crystal deposition in a patient with normal plasma ornithine levels.

CASE REPORT

A 50-year-old Hispanic female patient presented with complaints of blurred vision and nyctalopia. Examination revealed bilateral multiple round islands of peripheral chorioretinal degeneration in addition to small crystal-like deposits in the posterior pole. Spectral domain optical coherence tomography confirmed the crystalline deposits to be above the retinal pigment epithelium. Electrophysiology revealed reduced photopic responses with no recordable scotopic response. Testing for elevated plasma ornithine, which is typical in gyrate atrophy patients, was performed; however, the patient's levels were normal.

CONCLUSIONS

Diagnosis of conditions that cause nyctalopia can be challenging because they are rare and often similar in appearance and presenting symptoms. Retinal crystal deposition and normal plasma ornithine illustrate the phenotypical variation that can be seen in a gyrate atrophy-like phenotype.

To stop or not? Tamoxifen therapy for secondary prevention of breast cancer in a patient with ocular toxicity

We report a case of a patient with treated breast cancer whose dilated fundus examination showed crystalline deposits in the central region of the macula. She was taking tamoxifen for secondary prevention. Optical coherence tomography revealed individual refractile deposits associated with intraretinal cysts in both eyes. Tamoxifen-related retinopathy was suspected. A decision to discontinue treatment with tamoxifen was considered but had to be taken in conjunction with the oncologist.

Tamoxifen toxicity in cultured retinal pigment epithelial cells is mediated by concurrent regulated cell death mechanisms

PURPOSE

To evaluate the mechanism of tamoxifen-induced cell death in human cultured RPE cells, and to investigate concurrent cell death mechanisms including pyroptosis, apoptosis, and necroptosis.

METHODS

Human RPE cells were cultured until confluence and treated with tamoxifen; cell death was measured by detecting LDH release. Tamoxifen-induced cell death was further confirmed by 7-aminoactinomycin D (7-AAD) and annexin V staining. Lysosomal destabilization was assessed using lysosomal-associated membrane protein-1 (LAMP-1) and acridine orange staining. The roles of lysosomal enzymes cathepsin B and L were examined by blocking their activity. Caspase activity was evaluated by caspase-1, -3, -8, and -9 specific inhibition. Cells were primed with IL-1α and treated with tamoxifen; mature IL-1β production was quantified via ELISA. Caspase activity was verified with the fluorochrome-labeled inhibitor of caspases (FLICA) probe specific for each caspase. Regulated cell necrosis or necroptosis was examined with 7-AAD and inhibition of receptor-interacting protein 1 (RIP1) kinase using necrostatin-1 (Nec-1).

RESULTS

Cell death occurred within 2 hours of tamoxifen treatment of confluent RPE cells and was accompanied by lysosomal membrane permeabilization. Blockade of cathepsin B and L activity led to a significant decrease in cell death, indicating that lysosomal destabilization and cathepsin release occur prior to regulated cell death. Tamoxifen-induced toxicity was shown to occur through both caspase-dependent and caspase-independent cell death pathways. Treatment of RPE cells with caspase inhibitors and Nec-1 resulted in a near complete rescue from cell death.

CONCLUSIONS

Tamoxifen-induced cell death occurs through concurrent regulated cell death mechanisms. Simultaneous inhibition of caspase-dependent and caspase-independent cell death pathways is required to protect cells from tamoxifen. Inhibition of upstream activators, such as the cathepsins, may represent a novel approach to block multiple cell death pathways.

Canthaxanthin retinopathy with visual loss: a case report and review

Canthaxanthin is a naturally occurring chemical, which is most commonly utilized as a colorant for food and dyes or a skin bronzing agent. Its most prevalent impact on human health is canthaxanthin retinopathy, which appears as birefringent, yellow to red crystals surrounding the macula. This occurs with increasing, dose-dependent exposure. Generally, patients remain asymptomatic and findings may only be evident on funduscopic examination. Cessation of canthaxanthin ingestion appears to reverse the retinopathy, but the time until crystal disappearance is variable. Despite a usually favorable outcome, long-standing visual changes may occur. We report a case of an 84-year-old woman with significant visual loss secondary to canthaxanthin retinopathy that ultimately improved upon cessation of the drug.

Retinal crystals in type 2 idiopathic macular telangiectasia

PURPOSE

To characterize the phenotype and investigate the associations of intraretinal crystalline deposits in a large cohort with type 2 idiopathic macular telangiectasia (MacTel).

DESIGN

Case-control study.

PARTICIPANTS

Patients with and without retinal crystals from the Macular Telangiectasia Project, an international multicenter prospective study of type 2 MacTel.

METHODS

Grading of stereoscopic 30-degree color fundus (CF), confocal blue light reflectance (CBR), red-free (RF), and infrared (IR) images was performed according to the MacTel Natural History Study protocol and staged using the classification system devised by Gass and Blodi. Spectral domain-optical coherence tomography (SD-OCT) and adaptive optics imaging were used for a finer analysis of the phenotype. Associations between crystals and other characteristics of the disease, as well as potential risk factors, were investigated.

MAIN OUTCOME MEASURES

Presence of crystals, fundus signs of MacTel, clinical characteristics, and presence of potential risk factors of MacTel.

RESULTS

Of 443 probands enrolled in the MacTel study, 203 (46%) had crystalline deposits present; 60% of the cases were bilateral at baseline. Eyes with crystals had a mean letter score of 70.7 (standard deviation [SD] = 15.9), whereas those without crystals had a mean letter score of 66.5 (SD = 15.5, P < 0.001). Crystals were present at all stages of the disease and showed high reflectivity within a wide wavelength range. They were located at the anterior surface of the nerve fiber layer, arranged along the nerve fibers, within an annular area centered on the fovea. Significant associations of crystalline deposits were found with a loss of retinal transparency, macular pigment optical density (MPOD) loss, fluorescein leakage, retinal thickness, and a break in the inner segment/outer segment junction line. Associations with environmental risk factors were not found.

CONCLUSIONS

Intraretinal crystals are a frequent phenomenon associated with type 2 MacTel. They may appear at all stages and aid in the early diagnosis of the disease. Their morphology further implicates Müller cells in the pathogenesis of the disease. Insight into their physical and chemical properties may provide clues to the metabolic pathways involved in the pathogenesis of the disease.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found after the references.

Intraretinal crystalline deposits in neovascular age-related macular degeneration

PURPOSE

The purpose of this study was to describe intraretinal crystalline deposits detected in eyes with neovascular age-related macular degeneration.

METHODS

A retrospective review of patients seen during a 6-month period with the diagnosis of neovascular age-related macular degeneration was performed to identify patients with intraretinal crystalline deposits, defined as pinpoint refractile bodies within the neurosensory retina. The characteristics of the deposits, including their shape, size, distribution, and location within the retina, were determined by analyzing color and red-free fundus photographs and spectral domain-optical coherence tomography images.

RESULTS

Fourteen eyes of 13 patients with neovascular age-related macular degeneration manifesting intraretinal crystalline deposits were identified. The patients had no history of ocular or systemic disease or prior medication use known to be associated with intraretinal crystals. Intravitreal antivascular endothelial growth factor injection was used in 10 eyes, laser photocoagulation in 3 eyes, and intravitreal triamcinolone in 1 eye. The retinal crystals were detected in the macula overlying or adjacent to the areas of choroidal neovascularization. The crystalline deposits could be localized with spectral domain-optical coherence tomography to both the outer nuclear and the outer plexiform layers.

CONCLUSION

Intraretinal crystalline deposits localized to the outer nuclear and outer plexiform layers can be detected in eyes with a history of neovascular age-related macular degeneration, often after treatment with a variety of different modalities. Potential etiologies of these deposits include residual lipid material from choroidal neovascularization leakage, degenerated Müller cell elements, and because these deposits were found in eyes with assorted forms of treatment, an external factor such as diet may play a role.

Gold standards in pharmacovigilance: the use of definitive anecdotal reports of adverse drug reactions as pure gold and high-grade ore

Anecdotal reports of adverse drug reactions are generally regarded as being of poor evidential quality. This is especially relevant for postmarketing drug safety surveillance, which relies heavily on spontaneous anecdotal reports. The numerous limitations of spontaneous reports cannot be overemphasised, but there is another side to the story: these datasets also contain anecdotal reports that can be considered to describe definitive adverse reactions, without the need for further formal verification. We have previously defined four categories of such adverse reactions: (i) extracellular or intracellular tissue deposition of the drug or a metabolite; (ii) a specific anatomical location or pattern of injury; (iii) physiological dysfunction or direct tissue damage demonstrable by physicochemical testing; and (iv) infection, as a result of the administration of an infective agent as the therapeutic substance or because of demonstrable contamination. In this article, we discuss the implications of these definitive ('between-the-eyes') adverse effects for pharmacovigilance.

Parafoveolar intraretinal crystals in pearson syndrome

PURPOSE

To describe the occurrence of bilateral parafoveolar intraretinal crystals in a patient with Pearson syndrome (bone marrow-pancreas syndrome).

METHODS

A patient with an established diagnosis of Pearson syndrome underwent complete ophthalmic examination and optical coherence tomography.

RESULTS

Fine, refractile, crystalline, parafoveolar intraretinal deposits were seen bilaterally. There was no evidence of pigmentary retinopathy or ophthalmoplegia.

CONCLUSIONS

Intraretinal crystals in the macula may be seen in Pearson syndrome and may not cause a substantial decrease in visual acuity. Pearson syndrome should be considered in the differential diagnosis of parafoveolar crystalline retinopathy.

Ocular features of Sjogren?Larsson syndrome

Sjogren-Larson syndrome is a rare autosomal recessive neurocutaneous disorder characterized by a triad of intellectual disability, spastic diplegia or tetraplegia and congenital ichthyosis with associated ocular features, which include pigmentary changes in the retina. The usual presentation of crystalline maculopathy is from the age of 1-2 years onwards. Herein, a case of Sjogren-Larson syndrome in a 25-year-old woman is presented to highlight the ocular findings.

Crystalline Retinopathies

Many types of crystalline retinopathies have been described, associated with a myriad of medical conditions ranging from chronic retinal conditions to inherited systemic diseases. This comprehensive review summarizes the different types of crystalline retinopathies, including their clinical presentations, diagnostic criteria, pathology, and treatment options.

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.

Refractile superficial retinal crystals and chronic retinal detachment: case report

Background

Few 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 presentation

Two 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.

Conclusion

This 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.