Tamoxifen therapy conveys increased risk of developing a macular hole

Etiology of Idiopathic Macular Holes in the Light of Estrogen Hormone

The aim of this review was to identify a new potential explanation for the development of macular holes in relation to the female sex and to explain the possible underlying pathways. This approach was based on the evaluation of anatomical, physiological, and morphological analyses currently available in the literature. The findings showed that estrogen exerts a protective effect on the neuroretina and may influence Müller and cone cells. Both cell types are responsible for the building of the fovea structure. However, this protection may be lost due to the sudden decrease in estrogen levels during menopause. In conclusion, the fovea cones, through its sensitivity to estrogen and high energy consumption, may be very vulnerable to damage caused by a sudden changes in the concentration of estrogen in menopausal females. Such changes may result in cone degeneration, and thus a destroyed structure of the fovea, and may lead to the development of a hole in the fovea, as in the case of macular holes. This review revealed that under the decreasing influence of estrogen may cones play a key role with regard to the etiology of the development of macular holes. This aspect may be of strategic importance in prophylactic therapy for the prevention of the development of macular holes in premenopausal females or after ocular trauma.

Tamoxifen induced maculopathy presenting like macular telangiectasia type 2 in a patient with breast cancer

INTRODUCTION

Drug-induced crystalline maculopathy has been reported secondary to tamoxifen use for breast cancer treatment. It could be misdiagnosed as macular telangiectasia type 2 (MacTel type 2).

CASE REPORT

A 56-year-old woman with a history of diabetes mellitus and breast cancer was referred to our clinic with painless, bilateral, gradual onset of central vision loss for several months. The fundus examination showed the macular pigmentary change in both eyes and a few refractile crystalline deposits in the parafoveal area in the left eye. However, the rest of the retina was normal in both eyes.

MANAGEMENT AND OUTCOME

With the diagnosis of tamoxifen-induced maculopathy, the drug was discontinued and supplementary treatment was started.

DISCUSSION

In this report, patient medical and drug history was an important and powerful measure. Due to the side effects of long-term use of tamoxifen, we need further studies on the need for retinal screening in these patients.

Tamoxifen retinopathy

Tamoxifen (TAM) is a selective estrogen receptor modulator that is used in the treatment of breast cancer. As there are estrogen receptors in the retina, retinal pigment epithelium, and choroid, these tissues may also be affected by TAM. We describe the reported effects of TAM on the retina and choroid. Medical databases were searched using relevant keywords and the results were extracted and pooled. The incidence of retinal/choroidal toxicity ranged from 0.9% to 12%. There was a wide range for the time of exposure before the development of TAM retinopathy (3 weeks to 13 years). While functional measurements may be appropriate for assessment of TAM retinopathy, they have not been effective for screening patients. There is no generally accepted screening modality, but serial funduscopy and optical coherence tomography imaging seem to be the most reasonable approach for detecting early TAM-induced retinal toxicity.

Partial thickness subfoveal hole in a patient treated with tamoxifen: a case report and review of the literature

BACKGROUND

We describe a patient presenting with a partial thickness subfoveal hole in the right eye after tamoxifen treatment for breast cancer.

CASE PRESENTATION

A 76-year-old Caucasian female presented with a 1-day history of acute central scotoma and blurry vision in the right eye. The patient had been receiving oral tamoxifen for 5 years as adjuvant treatment for stage I lobular breast cancer. Her past ocular history was significant for complete, uneventful, and bilateral posterior vitreous detachment. Clinical examination and optical coherence tomography revealed a new, partial thickness subfoveal hole sparing the inner retinal layers. Observation was recommended. At the last follow-up examination, 1 year after the initial presentation, the subfoveal hole remained stable and visual acuity remained stable.

CONCLUSION

Tamoxifen has been associated with a plethora of ophthalmic adverse events, including macular holes, some of which are partial thickness subfoveal holes. Holes with this almost unique morphology are uncommon, and eye care professionals should be aware of this association given the frequency of tamoxifen use, as well as the low success rate of surgical repair with pars plana vitrectomy.

[Effects of systemic drugs on the development of drug-induced retinopathy]

This article reviews information on possible adverse events occurring in the organ of vision - in particular, the retina - after using systemic drugs, discusses the drugs that lead to drug-induced retinopathy most often, and describes histomorphological changes and modern understanding of the pathogenesis of damage to retinal structures.

Retinal toxicities of systemic anticancer drugs

Newer anticancer drugs have revolutionized cancer treatment in the last decade, but conventional chemotherapy still occupies a central position in many cancers, with combination therapy and newer methods of delivery increasing their efficacy while minimizing toxicities. We discuss the retinal toxicities of anticancer drugs with an emphasis on the mechanism of toxicity. Uveitis is seen with the use of v-raf murine sarcoma viral oncogene homolog B editing anticancer inhibitors as well as immunotherapy. Most of the cases are mild with only anterior uveitis, but severe cases of posterior uveitis, panuveitis, and Vogt-Koyanagi-Harada-like disease may also occur. In the retina, a transient neurosensory detachment is observed in almost all patients on mitogen-activated protein kinase kinase (MEK) inhibitors. Microvasculopathy is often seen with interferon α, but vascular occlusion is a more serious toxicity caused by interferon α and MEK inhibitors. Crystalline retinopathy with or without macular edema may occur with tamoxifen; however, even asymptomatic patients may develop cavitatory spaces seen on optical coherence tomography. A unique macular edema with angiographic silence is characteristic of taxanes. Delayed dark adaptation has been observed with fenretinide. Interestingly, this drug is finding potential application in Stargardt disease and age-related macular degeneration.

Ocular Toxicity of Targeted Anticancer Agents

The proliferation of targeted anticancer agents over the last two decades has revolutionized cancer treatment and improved survival in many previously refractory malignancies. However, many agents are associated with characteristic ophthalmic adverse effects. It is important that ophthalmologists recognize and maintain a high index of suspicion for these side effects in patients on targeted therapy. Most ophthalmic adverse effects can be treated with specific ocular therapy without discontinuation of cancer treatment, although it is important to be aware of the life-threatening and vision-threatening circumstances that would require therapy cessation in conjunction with the patient's oncologist. This review aims to summarize the ophthalmic adverse effects of targeted and hormonal anticancer agents and briefly describe their management.

Bilateral Macular Hole Related to Tamoxifen Low-Dose Toxicity

Bilateral macular hole is a rare secondary effect of tamoxifen, a condition which is probably underdiagnosed. We describe the case of a 63-year-old woman who had received low-dose treatment with tamoxifen for 10 years. She presented with a best-corrected visual acuity of 20/40 in both eyes and bilateral macular hole with posterior hyaloid attachment. No reflective deposits were observed. A 23-gauge pars plana vitrectomy with internal limiting membrane peeling and gas tamponade was performed in the right eye with no anatomical or functional improvement. The most accepted mechanism of macular hole related to tamoxifen is Müller cell toxicity with retinal tissue loss. Therefore, it seems that the standard procedure used in idiopathic macular hole is not the optimal choice, due to a different pathogenic mechanism.

Tamoxifen Induced Pachychoroid Pigment Epitheliopathy with Reversible Changes After Drug Discontinuation

We report a case of breast cancer with clinically significant retinal toxicity induced by 7 years’ Tamoxifen consumption in which patient’s visual acuity and paraclinical findings remarkably improved after drug discontinuation. A 49-year-old woman with a history of breast cancer and Tamoxifen consumption was referred to our clinic for evaluation and treatment of gradual and progressive decrease visual acuity of both eyes (more prominent in right eye). Funduscopy showed bilateral macular pigmentary changes, with diffused tiny yellow crystals and reduced macular tessellation. On spectral-domain optical coherence tomography (SD-OCT), there was retinal pigment epithelium (RPE) abnormality and ellipsoid zone discontinuity accompanied by retinal thinning and choroidal thickness that was more prominent in the right eye. One year after discontinuation of the drug, visual acuity was significantly improved and SD-OCT revealed some surprising recoveries in the photoreceptor layers especially in her right eye.

The effects of adjuvant hormonotherapy on tear functions in patients with breast cancer

PURPOSE

Aromatase inhibitors (anastrozole, letrozole) and selective estrogen receptor modulators (tamoxifen) are widely used as adjuvant hormonal therapy in women with hormone receptor-positive breast cancer. We aimed to evaluate the effects of oral adjuvant hormonotherapy on tear functions in patients with breast cancer.

METHODS

In this case-control study, we enrolled eligible patients with breast cancer who were receiving regular medical selective estrogen receptor modulator (tamoxifen, n:50), aromatase inhibitors (anastrozole, letrozole, n:50) and gender-matched healthy controls (n:50). Tear functions were measured and compared by the Schirmer test, fluorescein breakup time, corneal staining evaluated by Oxford grading scale and Ocular Surface Disease Index scores.

RESULTS

Mean age was 49.95 (± 9.2), 51.52 (± 7.2) and 51.91 (± 10.3) in tamoxifen, aromatase inhibitors groups and controls (p = 0.426). Mean duration of BC diagnosis (p = 0.536) and drug use (p = 0.417) was not significant between two groups. Ocular Surface Disease Index scores were lower (p < 0.001), and fluorescein breakup time measurements were higher (p < 0.001) in controls. Schirmer test scores were higher in controls than aromatase inhibitors group (p < 0.001). According to the scores of all measurements, the differences between aromatase inhibitors and tamoxifen groups were statistically significant (p < 0.001).

CONCLUSIONS

Our results demonstrated a high difference in all parameters in patients receiving aromatase inhibitors compared to tamoxifen group and controls. Aromatase inhibitors, which reduce estrogen levels in the blood, might affect the tear functions more than tamoxifen, which affects as antiestrogenic on estrogen receptors.

The Effects of Adjuvant Tamoxifen Use on Macula Pigment Epithelium Optical Density, Visual Acuity and Retinal Thickness in Patients with Breast Cancer

Purpose: We aimed to compare best corrected visual acuity, macular pigment optical density and macular thickness in patients with breast cancer, who received oral adjuvant hormone therapy.Materials and Methods: We enrolled consecutive eligible patients with breast cancer who were receiving regular medical tamoxifen treatment. The participants were divided into two groups as cases and controls. Best-corrected visual acuity and retinal thickness were examined. Macular pigment optical density was measured by fundus reflectometry using the one-wavelength reflection method. The output parameters included max optical density, mean optical density, volume and area of the right eye.Results: A total of 104 eyes, cases (n: 50) and controls (n: 54) were included in the study. Mean age in cases was 49.95 ± 9.2 years and 50.21 ± 9.3 years in controls (p = .151). The mean foveal optical density and the maximum optical density differed between cases (0.13 ± 0.03 density units (DU)/0.35 ± 0.07 DU) and controls (0.18 ± 0.04 DU/0.41 ± 0.06 DU) (p = .002/p = .009). Macular pigment optical density volume was 8102.84 ± 2412.67 in cases versus 8280.18 ± 2904.56 in controls (p = .034), and mean MPOD area was 59567.79 ± 11538.06 in cases versus 61748.14 ± 10591.19 in controls (p = .023). The best corrected visual acuity and retinal thickness were similar in both groups (p > .05).Conclusions: Patients in care of oral tamoxifen therapy were found to have significantly reduced macular pigment optical density. In addition, higher drug use duration correlated significantly with reduced macular pigment optical density, suggesting that the poor long-term effects may play a role in macular pigment absorption and incorporation in the retinal tissue.

Sex-Dependent Choroidal Thickness Differences in Healthy Adults: A Study Based on Original and Synthesized Data

PURPOSE

The purpose of this study is to determine the influence of sex on choroidal thickness (CT) in healthy adults.

METHODS

Healthy Chinese adults were recruited and complete ophthalmic examinations were performed. The choroid was imaged by swept-source optical coherence tomography and the macular CT in Early Treatment Diabetic Retinopathy Study grids was obtained by the intrinsic automated segmentation software. CT in males and females was compared after controlling other factors. All of the published studies in PubMed were systemically tracked, and a syntheses analysis of the combined data of the present study and previous studies was performed to address this issue further.

RESULTS

A total of 104 healthy adults were included, of whom 38 (37%) were male and 66 (63%) were female. Older age and longer axial length (AL) each were significantly associated with thinner CT. After controlling for age and AL, the foveal CT and average macular CT were 25.5 μm (95% CI: 0.5-50.4 μm) and 22.1 μm (95% CI: 2.7-41.4 μm) thicker in men than in women, respectively. Significant differences in CT between males and females were also observed in inner and outer rings after controlling for age and AL (P < 0.05). After strict screening, 15 previously reported studies were determined to be eligible for inclusion. The combination of data collected from 2821 males and 3389 females provided further evidence that the choroid is thicker in males, with a pooled mean difference of 19.5 μm (95% CI: 11.4 to 27.6) for foveal CT and 14.7 μm (95% CI: 6.8 to 22.6) for average CT.

CONCLUSION

Our study of Chinese subjects, along with the syntheses analysis, strengthens the evidence that CT is greater in males than in females, based on OCT measurements. This observation may be pertinent for the sex disparities in some clinical conditions related to CT.

Tamoxifen Use in a Patient with Idiopathic Macular Telangiectasia Type 2

Crystalline deposits and neurosensory retinal cavitary changes can develop in both tamoxifen retinopathy and nonproliferative idiopathic macular telangiectasia type 2 (MacTel2). MacTel2 is typically differentiated from tamoxifen retinopathy based on the presence of late leakage and mid-phase telangiectatic vessels on fluorescein angiography (FA) and the presence of hyperautofluorescence. Unlike MacTel2, tamoxifen retinopathy is known to be a progressive disease and the cessation of tamoxifen results in resolution of retinopathy. We report a unique case of nonproliferative MacTel2 in a 36-year-old Hispanic woman with tamoxifen use and the vision outcome 30 months after cessation of tamoxifen. The FA and optical coherence tomography angiography findings of this patient support the diagnosis of MacTel2, but her cessation of tamoxifen led to partial reversal of the topographic findings and improvement in visual acuity. This patient is also unique in the unusually young age of presentation for MacTel2. Our case supports that there are common pathways in the pathogenesis of tamoxifen retinopathy and MacTel2, and tamoxifen use could potentially accelerate foveal atrophy in patients with MacTel2.

Electroretinographic and optical coherence tomography findings in breast cancer patients using aromatase inhibitors

BACKGROUND

The present cross-sectional study has the purpose to investigate the impact of aromatase inhibitors (AIs) on retinal nerve fiber layer (RNFL) thickness, optic nerve and macular function in patients using AIs for breast cancer treatment.

METHODS

Participants in our study were 41 hormone-receptor-positive earlystage breast cancer patients who were treated with AIs in the adjuvant setting. Moreover, 40 age- and gender-matched control subjects, having neither ocular nor systemic disorders, were included in this study. All participants underwent a complete ophthalmological examination, including best corrected visual acuity (BCVA) assessment, RNFL thickness and central foveal thickness (CFT) measurement, visual evoked potentials (VEP) recording and multifocal-electroretinogram (mf-ERG) recording. Univariate and multiple regression analyses were performed.

RESULTS

At the multiple regression analyses, patients receiving AIs presented with lower average RNFL and inferior RNFL. Moreover, similarly to the univariate analysis, intake of AIs was associated with lower amplitude P100, lower retinal response density in ring 1 and ring 2, longer peak time P100 and longer P1 time in ring 1.

CONCLUSION

Our study is the first in the literature investigating the potential effect of AIs on RNFL thickness, optic nerve and macular function in patients using AIs for breast cancer treatment. The principal message of our study is that patients using AIs exhibited a significant decrease in RNFL thickness (average, superior and inferior), retinal response density and visual acuity compared to healthy controls, while VEP findings (both amplitude and peak time of P100) differ significantly as well.

Pseudocystic foveal cavitation in tamoxifen retinopathy

PURPOSE

To present 3 cases of tamoxifen-induced foveal cavitation and review previous prospective and cross-sectional studies.

DESIGN

Observational case series.

METHODS

Retrospective analysis of patients presenting to a single institution with evidence of tamoxifen-induced maculopathy.

RESULTS

Three patients presented with pseudocystic foveal cavitation similar in appearance to macular telangiectasia type 2 on spectral-domain optical coherence tomography (SD OCT) imaging.

CONCLUSIONS

Tamoxifen maculopathy is characterized by cavitation in the central macula with or without typical cystoid macular edema. Pathogenesis involves toxicity to retinal Müller cells. It can occur with low daily and cumulative doses of the drug, and in the absence of subjective visual complaints or crystalline retinopathy. Prospective research with SD OCT imaging will be required to gain a more accurate estimate of the incidence of tamoxifen retinopathy.

Ocular side effects of biological agents in oncology: what should the clinician be aware of?

During the last 20 years, biologicals have become increasingly relevant in oncologic therapy. Depending on the medication used, there are different profiles of ocular side effects. Although these can be present in up to 70% of patients, they are generally underreported in the literature. Therefore, the pathophysiological details of their development are often poorly understood. Herein we attempt to identify groups of biologicals to which a specific side effect profile can be assigned. We also tried to capture all relevant side effects and therefore conducted several database investigation including Medline, Cochrane library, and the drugs section of the US Food and Drug Administration (FDA), using the following search strings: “name of biological agent (both generic and commercial names)” AND “eye” OR “ocular”. If we found a side effect that has been associated with a drug, we researched Medline using the following search string: “name of biological agent” (both generic and commercial names) AND “term for the specific side effect”. Due to the wealth of material we report only the drugs that are approved by the FDA.

Breast cancer medications and vision: effects of treatments for early-stage disease

This review concerns the effects on vision and the eye of medications prescribed at three phases of treatment for women with early-stage breast cancer (BC): (1) adjuvant cytotoxic chemotherapy, (2) adjuvant endocrine therapy, and (3) symptomatic relief. The most common side effects of cytotoxic chemotherapy are epiphora and ocular surface irritation, which can be caused by any of several different regimens. Most notably, the taxane docetaxel can lead to epiphora by inducing canalicular stenosis. The selective-estrogen-receptor-modulator (SERM) tamoxifen, long the gold-standard adjuvant-endocrine-therapy for women with hormone-receptor-positive BC, increases the risk of posterior subcapsular cataract. Tamoxifen also affects the optic nerve head more often than previously thought, apparently by causing subclinical swelling within the first 2 years of use for women older than ∼50 years. Tamoxifen retinopathy is rare, but it can cause foveal cystoid spaces that are revealed with spectral-domain optical coherence tomography (OCT) and that may increase the risk for macular holes. Tamoxifen often alters the perceived color of flashed lights detected via short-wavelength-sensitive (SWS) cone response isolated psychophysically; these altered perceptions may reflect a neural-response sluggishness that becomes evident at ∼2 years of use. The aromatase inhibitor (AI) anastrozole affects perception similarly, but in an age-dependent manner suggesting that the change of estrogen activity towards lower levels is more important than the low estrogen activity itself. Based on analysis of OCT retinal thickness data, it is likely that anastrozole increases the tractional force between the vitreous and retina. Consequently, AI users, myopic AI users particularly, might be at increased risk for traction-related vision loss. Because bisphosphonates are sometimes prescribed to redress AI-induced bone loss, clinicians should be aware of their potential to cause scleritis and uveitis occasionally. We conclude by suggesting some avenues for future research into the visual and ocular effects of AIs, particularly as relates to assessment of cognitive function.

Imaging tamoxifen retinopathy using spectral-domain optical coherence tomography

A case of tamoxifen retinopathy examined with spectral-domain optical coherence tomography (SD-OCT) is presented. The typical refractile deposits are located between ganglion cell layer and inner plexiform layer in SD-OCT. A defect on the outer retinal layer with disruption of the photoreceptor layer with sharp edges is seen. The still attached posterior hyaloids gives evidence of other pathomechanism involved in the outer retinal defect than that of macular hole, as suggested in the literature.

Estrogen antagonist and development of macular hole

To describe the clinical and optical coherence tomography (OCT) features of a macular hole (MH) or its precursor lesion in patients treated with systemic antiestrogen agents. We reviewed the medical history of the patient, ophthalmic examination, and both fundus and OCT findings. Three female patients receiving antiestrogen therapy sought treatment for visual disturbance. All of the patients showed foveal cystic changes with outer retinal defect upon OCT. Visual improvement was achieved through surgery for the treatment of MH in two patients. Antiestrogen therapy may result in MH or its precursor lesion, in addition to perifoveal refractile deposits. OCT examination would be helpful for early detection in such cases.

Retinal function in patients treated with tamoxifen

Tamoxifen, an effective treatment of breast cancer, has been shown to cause ocular toxic effects. The purpose of this study was to determine retinal toxicity by full-field and focal electroretinograms (ERGs) in patients treated with tamoxifen. Fullfield and focal ERGs were obtained from three groups: Tamoxifen-14 females (47-72 years, mean 58.3 + or - 9.1) with normal fundus, treated with tamoxifen from 2 to 37 months; No Treatment-10 females (39-65 years, mean 50.1 + or - 8.7) with previous breast cancer diagnosis and before tamoxifen treatment; Control-13 normal female volunteers (41-81 years, mean 52.7 + or - 12.1). Peak-to-peak amplitude and b-wave implicit time were measured and statistically analyzed.Mean peak-to-peak amplitudes and implicit time from full-field and focal ERGs were comparable for the three different groups. Low-dosage tamoxifen showed no retinotoxic effect assessed by full-field and focal ERG in this small group of women with breast cancer.

Visual impairment in myopic patients with breast cancer receiving adjuvant therapy with aromatase inhibitors

Retinal structure and function is maintained in part by the trophic effects of aromatase, a cytochrome P450 convertase responsible for local tissue estrogen synthesis from androgen precursors. Herein, we report deterioration of visual acuity in 2 Chinese patients with breast cancer and preexisting myopia who had recently commenced adjuvant hormonal therapy using the aromatase inhibitor exemestane. Given the neuroprotective functions of estrogen and aromatase, we caution that this timing might not be coincidental. Prompt ophthalmoscopic evaluation is thus recommended for any patient who is prescribed treatment with an aromatase inhibitor and subsequently develops visual symptoms.

[Tamoxifen retinopathy: a case series of clinical and functional data]

BACKGROUND

Tamoxifen is used in the treatment of selected patients with breast carcinoma. Rarely, it has been shown to cause ocular toxic effects including crystalline retinopathy.

METHODS

Retrospective analysis of clinical and functional (visual acuity, visual field, colour vision) data of a case series of eight female patients under tamoxifen therapy with electrophysiological examination.

RESULTS

Seven of eight patients complained of visual disturbances. In one case, examination showed crystalline deposits in the cornea and macular area. Three patients revealed changes in full-field and multifocal electroretinogram, and two had a pathological multifocal electroretinogram only. In six cases we applied a desaturated panel D-15 colour vision test; five of these showed some disorders.

CONCLUSIONS

Most tamoxifen patients who complained of visual disturbances showed electrophysiological changes, particularly in the multifocal electroretinogram and often without a certain morphological correlate. We recommend electrophysiological examination for patients with unclear visual deterioration who are receiving tamoxifen therapy.

Vitreo-retinal traction and anastrozole use

PURPOSE

This study tested a prediction stemming from the hypothesis that anastrozole users experience heightened vitreo-retinal traction. This hypothesis was based on the knowledge that menopause increases the risk of intraocular tractional events such as posterior vitreous detachments (PVDs).

METHODS

Retinal thickness was measured for 3 groups of amenorrheic women: (1) anastrozole users and (2) tamoxifen users undergoing adjuvant therapy for early-stage breast cancer, and (3) control subjects not using hormonal medication. Foveal shape indices were derived for subjects without PVDs.

RESULTS

For anastrozole users, the distance to the temporal side of the fovea became less than the distance to the nasal side at a sufficient height above the foveal base. This effect did not exist for control subjects; the between-group difference was appreciable. Results concerning tamoxifen users were inconclusive.

CONCLUSIONS

The foveas of women using anastrozole appear to be subjected to more tractional force than are the foveas of women not using any hormonal medication.

Retinal hemorrhages in anastrozole users

PURPOSE

To determine whether women using anastrozole (an aromatase inhibitor, which suppresses estrogen synthesis) are likely to have retinal hemorrhages.

METHODS

Fundus photographs were obtained for a study comparing effects on vision and the eye of anastrozole (1 mg/d) and tamoxifen (20 mg/d) for women receiving adjuvant endocrine therapy for early-stage breast cancer. Photographs (2 eyes per subject) were evaluated for hemorrhages by an ophthalmologist masked from identifying subject information. The presence of hemorrhages was assessed for 35 anastrozole users, 38 amenorrheic tamoxifen users, and 53 amenorrheic (peri- or postmenopausal) control subjects not using any endocrine medication. The age range was 43 to 69 years; only subjects reporting normal vision and healthy eyes were recruited. Photographs from 36 tamoxifen users from a previous study also were assessed. Views of the fundus extended appreciably beyond the posterior pole for all tamoxifen and anastrozole users, and for 38 of the control subjects. Photographic assessments were compared with medical history and blood pressure data, and optical coherence tomography was used for quantifying aspects of foveal shape that might be affected by vitreoretinal traction.

RESULTS

Four anastrozole users and no contemporaneous tamoxifen users but one previously tested tamoxifen user had retinal hemorrhages, in each case within the posterior pole. Two anastrozole users had a flame hemorrhage (in the retinal nerve fiber layer), and two had a blot hemorrhage (deeper in the retina). No control subjects were observed to have hemorrhages.

CONCLUSIONS

Anastrozole use appears to be associated with an increased prevalence of retinal hemorrhages. The hemorrhages may mark systemic vascular compromise resulting from estrogen depletion, and/or they may be consequences of vitreoretinal traction resulting from estrogen depletion. They may also depend on the use of medications for controlling common anastrozole-induced side effects. Prospective studies need to be conducted with larger numbers of subjects.