Lipemia retinalis - an unusual cause of visual acuity deterioration

A multiomic study of retinal tissues in mice with direct ocular exposure to vesicants

This study employed a multiomic approach to investigate retinal tissue damage following direct ocular exposure (DOE) to vesicants (VSs)-namely, nitrogen mustard (NM) and lewisite (Lew). We explored both the acute and chronic stages of retinal injury by assessing functional, structural, and molecular changes. C57BL/6 mice were used to measure scotopic and photopic electroretinograms (ERGs) and to analyze TUNEL-positive retinal cells. Global retinal proteomics was conducted to identify common and unique signaling pathways. In addition, we performed targeted metabolomic and lipidomic analyses of retinal tissue to uncover significant metabolic changes. Our results demonstrated remarkable declines in ERG amplitudes at 2 and 4 weeks post-exposure, accompanied by an increase in TUNEL+ retinal cells in response to DOE to both VSs. Our proteomic analysis revealed chronic oxidative stress, mitochondrial dysfunction, elevated RXR signaling, and increased levels of 28 proteins. Moreover, we observed a decline in the KEGG phototransduction pathways, along with the downregulation of photoreceptor-specific proteins, in response to both VSs. Consistent with the proteomic findings, targeted metabolomics identified a decline in phototransduction and steroid hormone biosynthesis, along with increases in D-amino acid and purine metabolism, as well as lysine degradation. These changes were associated with a GSSG/GSH ratio of 2.6, confirming the proteomic data on oxidative stress. Furthermore, lipidomic analysis revealed an increase in oxidative lipid levels, accompanied by a 3.4-fold increase in phosphatidylserine (PS), suggesting apoptotic cell death and a reduction in fatty acids (FAs). In conclusion, exposure to both VSs induced progressive retinal damage, altering major metabolic pathways and dysregulating lipid metabolism. Future studies should focus on identifying the responses of individual neuronal cell types to DOE to VSs to develop cell-specific countermeasures.

Retinal thickness and fundus blood flow density changes in chest pain subjects with dyslipidemia

AIM

To assess the retinal thickness and fundus blood flow density changes in chest pain patients with dyslipidemia using optical coherence tomography angiography (OCTA).

METHODS

All subjects with chest pain as the main symptom accepted a comprehensive ophthalmological examination. According to the serum lipid levels, the participants were divided into the control group and the dyslipidemia group. The retina thickness and fundus blood flow density were determined using OCTA.

RESULTS

The study enrolled 87 left eyes from 87 adults with dyslipidemia and 87 left eyes from age- and sex-matched participants without dyslipidemia. The retina of dyslipidemia subjects was significantly thinner than that of the controls in the inferior (P=0.004 and P=0.014, respectively) and temporal (P=0.015 and P=0.019, respectively) regions, both inner and outer layers. In terms of blood flow density in the macula or optic disk, there was a decreasing trend in the dyslipidemia group compared with the control group, especially in the inferior and temporal regions.

CONCLUSION

Dyslipidemia may contribute to the decrease in retinal thickness and fundus blood flow density. Further validation of the association between abnormal lipid metabolism and fundus microcirculation alterations needs to be carried out in chest pain patients.

Incidental finding of lipaemia retinalis on diabetic retinal screening

SUMMARY

A 37-year-old female of South Asian origin was referred to our diabetes clinic for evaluation of an unusual finding during her retinal screening. Her retinal blood vessels appeared white in contrast to the normal pink-red colour. She had type I hyperlipidaemia, confirmed by genotype, and was recently diagnosed with diabetes, secondary to pancreatic insufficiency, for which she had suboptimal control and multiple hospitalisations with recurrent pancreatitis. On examination, she had multiple naevi on her skin; the rest of the examination was unremarkable. The patient did not report any visual disturbances and had intact visual acuity. Investigations showed raised total cholesterol (12.5 mmol/L) and triglycerides (57.7 mmol/L). Following evaluation, the patient was diagnosed with lipaemia retinalis, secondary to type I hyperlipidaemia. The patient was managed conservatively to reduce the cholesterol and triglyceride burdens. However, therapies with orlistat, statin, fibrates and cholestyramine failed. Only a prudent diet, omega-3 fish oil, medium-chain triglycerides oil and glycaemic control optimised with insulin showed some improvements in her lipid profile. Unfortunately, this led her to becoming fat-soluble vitamin deficient; hence, she was treated with appropriate supplementation. She was also recently started on treatment with volanesorsen. Following this, her lipid parameters improved and lipaemia retinalis resolved.

LEARNING POINTS

Lipaemia retinalis is an uncommon incidental finding of type I hyperlipidaemia that may not affect vision. Management of associated dyslipidaemia is challenging with minimal response to conventional treatment. Increased awareness of lipaemia retinalis and specialist management is needed as part of regular patient monitoring and personalised management.

Lipemia retinalis with different therapeutic responses: A report of two cases

Lipemia retinalis is characterized by retinal blood vessels that are creamy white in color and is considered to be directly correlated to serum triglyceride levels. It is a rare retinal manifestation, with typical serum triglyceride levels above 2500 mg/dL required for its expression. We report two cases of lipemia retinalis with hypertriglyceridemia who presented with different retinal pictures during a 5-year follow-up. One showed a normalization of retinal vessels even though the serum triglyceride level was still far more than 2500 mg/dL (4660 mg/dL), but the other had persistent creamy white discoloration despite decreases in serum triglyceride level to below 2500 mg/dL (1031 mg/dL). This suggests that the absolute serum triglyceride level may not be the sole determinant of the typical retinal manifestation. In spite of this, early detection that leads to timely treatment will assist in prevention of severe ocular and systemic vascular complications.

LIPEMIA RETINALIS DURING CHEMOTHERAPY WITH ADJUNCTIVE GLUCOCORTICOID TREATMENT IN A PATIENT WITH COLON CARCINOMA

PURPOSE

The purpose of this report is to describe a case of lipemia retinalis due to decompensating hyperlipidemia that occurred during chemotherapy in a patient with metastatic colon carcinoma.

METHODS

Retrospective case report.

RESULTS

A 55-year-old non-insulin-dependent diabetic man with well-controlled hyperlipidemia presented himself with temporarily blurred vision in both eyes occurring during chemotherapy. He was found to have lipemia retinalis in his both eyes. Blood tests revealed elevated cholesterol and triglyceride levels exceeding 8,200 mg/dL. He received six cycles of FOLFIRI/bevacizumab and accompanying dexamethasone because of colon cancer with pulmonary metastases. Lipemia retinalis had resolved after a 6-week follow-up when chemotherapy was finished, and the patients' triglyceride and glucose levels decreased to normal values.

CONCLUSION

Lipemia retinalis associated with visual impairment may occur during chemotherapy under accompanying treatment with dexamethasone. Even if patients with hyperlipidemia are metabolically well-controlled with oral medication, treatment with dexamethasone can potentially lead to decompensation of hyperlipidemia causing secondary lipemia retinalis.

Fundoscopic characteristics in three cases of familial hyperchylomicronaemia

CASES REPORT

Three cases are presented of patients with familial hyperchylomicronaemia and lipaemia retinalis, in whom an analysis is made of the fundoscopic characteristics of each of them.

DISCUSSION

The typical appearance of the retinal fundus is pale salmon coloured and corresponds to levels of severe lipaemia retinalis. As regards the findings, the vascular tree tonality is probably the best exploratory evidence to help in the ophthalmological diagnosis.

Statins in ophthalmology

Statins, 3-hydroxy-3-methyl-gutaryl coenzyme A reductase inhibitors, are a class of lipid-lowering drugs with anti-inflammatory, immunomodulatory, and vascular effects. Statins are increasingly being used in the treatment of a variety of medical conditions. We examine the actions of statins on the eye and its associated ophthalmic disorders. Statins can be synthetic or nonsynthetic, and their differentiating derivations may contribute to their varying cholesterol-lowering and pleiotropic effects. There is conflicting evidence on the ocular therapeutic and adverse effects of the statins. Statins may play a role in reducing the burden of dry eye, corneal ulcer scarring, thyroid-associated orbitopathy, glaucoma, uveitis and other associated ocular inflammatory states, cataract, proliferative vitreoretinopathy, diabetic retinopathy, macular degeneration, and choroidal melanoma. Topical preparations of statins can be formulated, thereby extending the range of ocular diseases that may be amenable to treatment. Statins have a relatively safe side effect profile, but rare and serious adverse reactions have been reported with their usage in ophthalmology, including myopathies and rhabdomyolysis with acute renal failure.

Lipemia retinalis as the presenting sign of undiagnosed type 1 diabetes mellitus resulting in severe secondary hypertriglyceridemia

We describe the clinical course of an 11-year-old girl diagnosed with lipemia retinalis as the presenting sign of diabetes mellitus type 1 with severe secondary hypertriglyceridemia. By performing serial multimodal imaging studies, we provide a comprehensive description of the clinical manifestations associated with severe hypertriglyceridemia to promote recognition of this rare clinical diagnosis.

Ultrawide field scanning laser ophthalmoscopy imaging of lipemia retinalis

OBJECTIVE

To describe the characteristic retinal features of lipemia retinalis when using ultrawide field scanning laser ophthalmoscopy.

MAIN POINTS

We report a case series of three subjects with ultrawide field retinal images showing cream discoloration of the fundus, light salmon-coloured posterior retinal vessels and greyish pink peripheral vasculature. On green-only imaging, many of the vessels appear light rather than typically dark.

CONCLUSION

Lipemia retinalis is readily apparent on ultrawide field imaging and illustrates the alterations that systemic diseases may induce in the posterior and peripheral retinal vasculature. Ultrawide field imaging highlights the disparate vascular appearance of the posterior pole and retinal periphery in this condition.

Mechanisms Underlying Early-Stage Changes in Visual Performance and Retina Function After Experimental Induction of Sustained Dyslipidemia

Visual and retinal function was measured in a mouse model of chemically induced, sustained dyslipidemia to determine the contribution of dyslipidemia to the pathogenesis of retinopathy in the context of metabolic syndrome. Fifteen male C57BL/6Crl mice were divided into three groups. Poloxamer 407 (P-407), 14.5% w/w was delivered at a rate of 6 µl/day by implanted osmotic mini-pumps either subcutaneously (P-407 SQ) or intraperitoneally (P-407 IP) to P-407-treated mice, whereas saline was administered at the same rate to control mice using only the subcutaneous route of administration. Total cholesterol (TC) and true triglyceride (TG) levels were quantified from plasma. Optomotor responses to stimuli of varying spatial frequency or contrast were used to measure visual acuity and contrast sensitivity. Retinal function was determined using Ganzfeld flash electroretinography (ERG). At 32 days, TC for the P-407 IP group was significantly elevated compared to saline controls (169.4 ± 16.5 mg/dl, 0.001 < P < 0.01). TG levels for both the P-407 SQ (59.3 ± 22.4 mg/dl, 0.01 < P < 0.05) and P-407 IP groups (67.7 ± 18.0 mg/dl, 0.001 < P < 0.01) were significantly elevated relative to controls. Electroretinography demonstrated a very significant decline in the b/a ratio (1.80 ± 0.11, P < 0.01) for the P-407 IP group. The b/a ratio exhibited a moderate, significant correlation with TC levels (r = - 0.4425, P = 0.0392) and a strong, very significant correlation with TG levels (r = - 0.6190, P = 0.0021). Delivery of P-407 via osmotic mini-pump resulted in the sustained, significant elevation of plasma TC and TG levels. This elevation in plasma lipid levels was correlated with a decline in inner retinal function.

Vasoregression: A Shared Vascular Pathology Underlying Macrovascular And Microvascular Pathologies?

Vasoregression is a common phenomenon underlying physiological vessel development as well as pathological microvascular diseases leading to peripheral neuropathy, nephropathy, and vascular oculopathies. In this review, we describe the hallmarks and pathways of vasoregression. We argue here that there is a parallel between characteristic features of vasoregression in the ocular microvessels and atherosclerosis in the larger vessels. Shared molecular pathways and molecular effectors in the two conditions are outlined, thus highlighting the possible systemic causes of local vascular diseases. Our review gives us a system-wide insight into factors leading to multiple synchronous vascular diseases. Because shared molecular pathways might usefully address the diagnostic and therapeutic needs of multiple common complex diseases, the literature analysis presented here is of broad interest to readership in integrative biology, rational drug development and systems medicine.

Statin therapy decreased the recurrence frequency of atrial fibrillation after electrical cardioversion: a meta-analysis

Background

It is unclear whether statin agents provide clinical benefit in preventing the relapse of atrial fibrillation (AF) after electrical cardioversion (EC). The purpose of this study was to assess the effect of statin agents on the recurrence of AF after EC by conducting a meta-analysis of randomized controlled trials (RCTs).

Material/Methods

We conducted a systematic literature search of Medline, EMBASE, ISI Web of Science, and Cochrane databases. RCTs comparing clinical endpoint of the recurrence of AF associated with statin administration vs. no statin treatment (placebo or conventional medical therapy) in patients with AF after EC were eligible. Combined results are presented as risk ratios (RRs) with 95% confidence intervals (CIs).

Results

A total of 5 trials with 524 patients were available for analysis. The pooling analysis showed that statin agents significantly reduced the recurrence of AF after EC compared with no statin treatment (RR=0.76, 95% CI 0.63–0.92; p=0.004; I²=44%). The beneficial effect was shown both in AF subjects receiving atorvastatin or rosuvastatin treatment (atorvastatin 80 mg: RR=0.82, p=0.05; atorvastatin 10 mg: RR=0.27, p=0.03; rosuvastatin: RR=0.38, p=0.04) and in younger patients (<65 years; RR=0.58, p=0.0005). Furthermore, the benefit of statin agents on preventing AF recurrence after EC was demonstrated within 3-month follow-up (p=0.03), and the clinical benefit seemed likely to remain until no less than 12 months after EC (p=0.05).

Conclusions

Based on the currently available data, administration of statin agents, especially atorvastatin or rosuvastatin, is beneficial in lowering the frequency of AF recurrence after EC.

Improved visual function with dietary intervention in a child with lipemia retinalis

We present a 4.8-year-old female with grade 3 lipemia retinalis due to lipoprotein lipase deficiency, an abnormal electroretinogram, and bilateral decreased visual acuity. Strict dietary intervention resulted in reversal of lipemia retinalis, normalization of her electroretinogram, and improved visual acuity in both eyes.