Multifocal electroretinography, color discrimination and ocular toxicity in tamoxifen use

PURPOSE: To study prospectively retinal function, color discrimination, and ocular toxicity in women treated with standard-dosage tamoxifen for breast cancer. METHODS: Thirty visually asymptomatic patients with at least 2 years of continuous tamoxifen therapy underwent multifocal electroretinography (ERG), color discrimination testing, and ophthalmic examination. The results were compared with 17 patients who were not taking tamoxifen after breast cancer surgery and to an additional age-matched group of 21 healthy women. RESULTS: Multifocal electroretinogram amplitudes and latencies were comparable among the three studied groups, and individual recordings were within age norms from our own lab. In the treated group, mild diffuse color vision loss was found in two patients with normal fundi. Three other patients had ocular toxic effects, with two cases of refractile retinal crystals and one case of keratopathy. CONCLUSIONS: The aspects of central retinal function that are assessed by multifocal ERG were not affected even after at least 2 years of tamoxifen use, suggesting that the multifocal ERG is not sufficiently sensitive to detect tamoxifen-associated change that might occur. Some degree of color vision loss and ocular toxic effects were found in a few cases of this cohort suggesting that women using tamoxifen should receive an eye exam at least as often as recommended for middle-aged people.     

Late onset cone dystrophy

Cone dystrophies are a hereditary, progressive and heterogeneous group of retinal diseases with cone system degeneration. They lead to reduced visual acuity, colour vision impairment and photophobia. Full-field electroretinogram (ERG) reveals severe cone function impairment, with normal rod responses or slightly depressed in advanced stages in some cases. The purpose of the study was to present a case of late onset cone dystrophy in 47-year-old male and the proper diagnostic procedure. A 47-year-old patient presented with progressive visual loss for several years and mild photophobia, which he observed recently. The patient underwent fundus photography, fluorescein angiography, colour vision testing, Goldmann visual field testing, full-field electroretinogram (ERG) and multifocal electroretinogram (mfERG). Symptoms and signs of late onset cone dystrophy may be unclear and establishing the proper diagnosis may be difficult in these cases. Patients may be misdiagnosed as having other diseases, especially in case of absence or subtle changes in the macula. The electrophysiological testing is essential in these cases, and ERG is the most useful clinical test in early and differential diagnosis of retinal dystrophies.     

Retinal dysfunction and anterior segment deposits in a patient treated with rifabutin

PURPOSE: To describe the clinical and electrophysiological findings in a young boy with decreased vision possibly due to retinal damage by rifabutin. METHODS: An 8-year-old boy with osteomyelitis was referred due to visual disturbance. During a period of 4 years, the boy was examined six times with electroretinography. Ophthalmological examination included testing of visual acuity, slit-lamp inspection, fundus inspection, fundus photography and kinetic perimetry. Two electrophysiological methods were performed for objective evaluation of retinal function, namely full-field electroretinography and multifocal electroretinography. RESULTS: We found a slightly reduced visual acuity, a slowly increasing amount of yellow-white deposits on the posterior surface of the cornea and on the anterior part of the lens, a normal fundus appearance, and normal visual fields. However, the electroretinogram was abnormal on several occasions during therapy with rifabutin, but returned to normal 3 months after withdrawal of the medication. The multifocal electroretinogram returned to normal after the full-field electroretinogram had done so. The anterior chamber deposits still remain. CONCLUSION: Long-term treatment with rifabutin may have a reversible and previously undescribed side-effect on retinal function. The drug may also accumulate irreversibly on the posterior surface of the cornea and on the anterior surface of the lens. We suggest that objective evaluation of retinal function with electrophysiological methods should be performed in patients with visual disturbance during treatment with rifabutin.     

Multifocal ERG in chloroquine retinopathy: regional variance of retinal dysfunction

· Background: A study was carried out to evaluate the regional variance of retinal dysfunction in chloroquine retinopathy. · Methods: In three patients with different stages of chloroquine retinopathy, ophthalmologic evaluations including recording of full-field electroretinogram (ISCEV standard) and multifocal electroretinogram were performed. · Results: In one patient with mild chloroquine retinopathy the visual acuity, visual fields and full-field electroretinogram were normal, but retinal dysfunction was indicated by color vision disturbances. The second patient had moderate chloroquine retinopathy with normal visual acuity, visual fields and dark-adapted full-field electroretinogram; light-adapted and flicker full-field electroretinogram responses were, however, borderline and color vision was abnormal. The third patient had severe chloroquine retinopathy with reduced visual acuity, visual field and color vision defects, and a reduced full-field electroretinogram. In the multifocal electroretinogram, recorded with 61 hexagons, amplitudes and implicit times were evaluated in rings surrounding the center. In all three patients severe dysfunction (either amplitudes or implicit times) was found in the parafoveal and perifoveal areas. In the fovea and towards the periphery the function was normal or only moderately reduced. · Conclusion: Chloroquine retinopathy of different severity presents with characteristic alterations in the multifocal electroretinogram. Regional distribution of cone dysfunction is in agreement with previously reported histologic findings. The multifocal electroretinogram can detect retinal dysfunction in chloroquine retinopathy even when the full-field electroretinogram is normal and retinal alterations are subtle. Received: 1 September 1998 Revised version reveived: 1 February 1999 Accepted: 10 February 1999     

Comprehensive functional vision assessment of patients with North Carolina macular dystrophy (MCDR1)

PURPOSE: Previous studies indicated abnormal development of fixation toward the optic nerve head in patients with the inherited retinal disease North Carolina macular dystrophy (NCMD). The implication of this development on functional vision and structural characteristics has not been described. METHODS: The anatomical characteristics of five NCMD-affected individuals were assessed by measuring the retinal thickness of the macula using optical coherence tomography. The underlying physiologic health of the retina was assessed using the multifocal ERG. Psychophysical assessment of remaining vision in the affected areas was done with a new microperimetry system that measures functional visual acuity at 27 discrete locations and the Humphrey visual field analyzer. RESULTS: All patients had better areas of visual sensitivity toward the nasal macula. Follow-up examination showed no changes in the clinical appearance of the retina. Visual acuities ranged from -0.10 logMAR (Snellen equivalent, approximately 20/16) to 0.50 logMAR (Snellen equivalent, approximately 20/63) in the better eye. No significant changes in visual acuity were found over time. Local multifocal electroretinogram deficits were found in all patients. Patients with grade 2 or 3 disease had large patches of decreased amplitudes and delayed implicit times. Results of the anatomical, electrophysiological, and psychophysical tests were consistent. CONCLUSION: The electrophysiological and psychophysical deficits found in patients with more severe disease were consistent with an abnormal development of fixation from the anatomical fovea toward the optic nerve head with the placement of the lesion temporal to fixation (into the nasal visual field).     

Melanoma-associated retinopathy versus abnormal retinal function due to interferon-alpha/Isotretinoin therapy in cutaneous malignant melanoma

PURPOSE: To analyze whether an abnormal retinal function in patients with a cutaneous malignant melanoma was due to paraneoplastic retinopathy or due to isotretinoin or interferon-alpha. METHODS: We studied 15 patients with malignant melanoma in stage IIa and IIb who are all participants in a randomized, multicentered, double-blind placebo-controlled clinical trial comparing interferon-alpha/isotretinoin versus interferon-alpha/placebo performed by the Department of Dermatology, University of Graz. Our assessment included a full ophthalmic history and examination, electrophysiological testing (ERG, EOG), dark adaption, color vision and visual field testing. RESULTS: The most prevalent ocular symptom patients complained about was ocular dryness (8 patients). Electrophysiological as well as psychophysical testings showed no abnormalities in 12 patients. In 1 patient the therapy was stopped because of electrophysiological and psychophysiological pathology. This patient suffered from severe reduction of night vision and visual disturbances. Another patient had had night blindness since childhood which remained stable. CONCLUSIONS: We postulate that in 1 of 15 patients, visual complaints are caused with a high probability by melanoma-associated retinopathy although, in the literature, isotretinoin is described to show similar effects on retinal function.     

The multifocal pattern electroretinogram in chloroquine retinopathy

PURPOSE: Optimal screening for ocular toxicity caused by chloroquine and hydroxychloroquine is still controversial. With the multifocal pattern electroretinogram (mfPERG), a new electrophysiological technique has recently become available to detect early changes of ganglion cells. In this study this new technique is applied to a series of 10 patients seen consecutively receiving long-term chloroquine medication. METHODS: In 10 patients receiving chloroquine medication, clinical examination, Amsler visual field testing and computerized color vision testing were performed. If toxicity was suspected, automated perimetry was carried out. In addition, in all patients conventional pattern electroretinogram (PERG) and mfPERG testing were performed. RESULTS: On clinical examination 8 patients showed no chloroquine-associated maculopathy, while 2 patients did. Of these 2, only 1 reported abnormalities when viewing the Amsler chart, while automated perimetry showed typical, ring-like paracentral scotomas in both affected patients and color vision was significantly abnormal. In the normal patients, 4 of 8 had a mild color vision disturbance, which correlated to age-related macular changes. The amplitudes of the PERG and the central (approximately 10 degrees ) responses of the mfPERG were markedly reduced in chloroquine maculopathy, while the latencies were unchanged. The peripheral rings of mfPERG (ranging to 48 degrees ) were not affected by chloroquine toxicity. Both PERG and mfPERG were less affected by age-related macular changes. CONCLUSIONS: The reduction of PERG and central mfPERG responses in chloroquine maculopathy may help with the early detection of toxicity.     

Tamoxifen side effects, age-related macular degeneration (AMD) or cancer associated retinopathy (CAR)?

PURPOSE. Differential diagnosis of maculopathies can be difficult but is important if patients also suffer from other diseases such as breast cancer treated with antiestrogens. The main possible diagnoses, especially in the elderly, are age-related macular degeneration, tamoxifen and cancer-associated retinopathy (CAR). METHODS. We describe an 84-year-old patient with breast and colon cancer, who complained of a decrease in visual acuity after treatment with low-dose antiestrogens. She underwent a general ophthalmological investigation, perimetry and electroretinographic examination with multifocal (m-ERG) and flash-electroretinogram (flash-ERG). RESULTS. Visual acuity was reduced to 1/50 and 0.3. The ophthalmological examination was normal, except for extensive bilateral maculopathy with shining crystalline deposits, central and peripheral visual field defects, slightly affected scotopic and photopic potentials in the flash-ERG, and an abnormal m-ERG. CONCLUSIONS. The findings are expected with age-related macular degeneration with crystalline drusen, but also with CAR. Even if the single and total dosage of antiestrogens given to the patient is sufficient to cause tamoxifen retinopathy, this diagnosis can be excluded because, in tamoxifen retinopathy unlike in the case presented here, the deposits are not distributed in all retinal layers.     

Atrophic tamoxifen maculopathy

Tamoxifen maculopathy is characterized by perifoveal white refractile deposits associated with pigmentary changes and cystoid macular edema. We report a case of atrophic maculopathy related to tamoxifen in a 70-year-old patient. Fundus examination showed refractile deposits in the macula predominantly in the left eye. Fundus autofluorescence demonstrated foveolar autofluorescence in both eyes. Fluorescein angiogram showed bilateral foveolar hyperfluorescence without leakage in the late phase. Optical coherence tomography disclosed an interruption of the photoreceptor layer in both eyes with a foveolar cystoid space. Multifocal electroretinogram showed bilateral alteration of the foveolar pic. The perifoveal foveolar cyst disappeared on OCT after discontinuation of tamoxifen. This case highlights the usefulness of optical coherence tomography and multifocal electroretinogram in the early diagnosis of atrophic form of tamoxifen maculopathy.     

Oligocone trichromacy: a rare and unusual cone dysfunction syndrome

AIM: To describe the phenotype of a case series of six patients with oligocone trichromacy. METHODS: The six affected individuals underwent an ophthalmological examination, electrophysiological testing and detailed psychophysical assessment. RESULTS: All six affected patients had a history of moderately reduced visual acuity (6/12 to 6/24) from infancy, not improved by full spectacle correction. They complained of mild photophobia and they were not aware of any colour vision deficiency. They had no nystagmus and fundi were normal. Electrophysiological testing revealed either absent/profoundly reduced cone flicker responses or preserved but delayed and mildly reduced flicker responses. Colour vision was found to be within normal limits, but some patients showed mildly elevated discrimination thresholds along all axes. CONCLUSION: The largest case series to date of patients with oligocone trichromacy is presented. The electrophysiological findings suggest that there may be more than one disease mechanism. The mode of inheritance is likely to be autosomal recessive, and while previous reports have suggested that this disorder is stationary, in one of these families there is clinical evidence of progression.     

Foveal cone dystrophy: diagnostic ranking of the multifocal electroretinogram

BACKGROUND: In case of visual loss without morphologic pathology differentiation between a functional visual loss and a retinal disorder may be difficult. PATIENTS AND METHODS: We report on two women, aged 33 and 44, who were complaining of a progressive visual loss occurring over the past several weeks to months. They were referred to our department with the presumed diagnosis of functional visual loss. Biomicroscopy of the anterior and posterior segments, perimetry (Goldmann), colour (FM-100-Hue-Test) and stereopsis testing (Lang-Stereotest), fluorescein angiography (FLAG) and electrophysiological testing (P-ERG, VECP, EOG, multifocal electroretinography [mfERG]) were performed. RESULTS: Visual acuity was 0.16 OU and 0.25 OU respectively. A small relative central scotoma (I/1) was detected by dynamic perimetry. Colour vision, random-dot stereopsis and the results of electrophysiological testing except multifocal electroretinography (mfERG) were normal. The mfERG was able to detect a cone dysfunction which was related to the fovea. CONCLUSION: In case of visual loss of unknown etiology electrophysiological testing is indicated. The mfERG as an objective diagnostic method is able to detect a foveal cone dystrophy.     

Elektrophysiologische Untersuchungen bei Mammakarzinompatientinnen mit Tamoxifen-Retinopathie

PURPOSE: Crystalline plaques in the cornea or the retinal nerve fiber layer are well-known side effects of tamoxifen therapy. We investigated whether electrophysiological methods for determining the function of the retinal nerve fiber layer and retinal pigment epithelium demonstrate changes in tamoxifen retinopathy. PATIENTS AND METHODS: We compared the right eyes of four women with breast cancer and mono- or bilateral tamoxifen retinopathy to ten right eyes of age-matched, eyehealthy patients who had not received tamoxifen by means of electrophysiological investigations (e.g., pattern-reversal electroretinography, flash electroretinography for the maximal combined response, electrooculography; ISCEV standard conditions). RESULTS: No significant differences were observed between patients with tamoxifen retinopathy and controls regarding mean visual acuity, basal level of the electro-oculographic standing potential, basal level on the Arden index, or any of the other electrophysiological potentials. CONCLUSIONS: Pattern-reversal electroretinographic measurements revealed no damage of retinal ganglion cells in the presence of crystalline plaques in the retinal nerve fiber layer. Electro-oculography did reveal differences, but these were not statistically significant, possibly due to the small number of cases.     

Acute effects of sildenafil on the electroretinogram and multifocal electroretinogram

PURPOSE: To evaluate the acute effects of sildenafil (Viagra; Pfizer, Inc, New York, New York) on the electroretinogram and multifocal electroretinogram. METHODS: Eighteen healthy individuals (ages 21-49 years) were studied; 14 were given 200 mg sildenafil orally and four were given only water. All subjects were tested before sildenafil and 1 hour after sildenafil (or water) with a desaturated Panel D-15 color test, a full-field standard electroretinogram, and a multifocal electroretinogram using the VERIS system; five subjects were also tested 5 hours after sildenafil. RESULTS: Responses from the subjects who received sildenafil were compared with those from the control subjects. At 1 hour after sildenafil, photopic single-flash waveforms were attenuated by 9% and scotopic maximal response amplitudes were increased slightly. Photopic and 30-Hz flicker electroretinogram responses were delayed; multifocal electroretinogram waveforms were delayed (5%-9%) and attenuated (14%-22%) across the posterior pole. These changes did not resolve by 5 hours. Nine of the subjects who had received sildenafil (64%) reported visual or systemic symptoms, including one who reported bluish vision. Ten of those subjects (71%) showed a slight increase in color test errors 1 hour after sildenafil. CONCLUSIONS: For at least 5 hours after taking 200 mg of sildenafil, cone function was slightly depressed in the macula and periphery, as measured by full-field electroretinogram and multifocal electroretinogram recordings. However, the affected electroretinogram and multifocal electroretinogram parameters still remained within normal limits.     

Peripheral retinopathy and maculopathy in high-dose tamoxifen therapy

PURPOSE: To describe the clinical, angiographic, and optical coherence tomography (OCT) features of high-dose tamoxifen retinopathy in three male patients. DESIGN: Observational case series. METHODS: A review of history, clinical examination, and findings on fluorescein angiography (FA) and optical coherence tomography (OCT) was conducted. RESULTS: Three male patients receiving high-dose tamoxifen therapy sought treatment for vision loss and a crystalline maculopathy. Crystalline deposits were noted in the peripheral retina of two patients. All the patients showed macular leakage by FA, but cystoid macular edema (CME) on OCT was detected in two patients. Inner retinal hyperreflective deposits were identified by OCT in all the patients. CONCLUSIONS: High-dose tamoxifen therapy may result in peripheral crystalline retinopathy in addition to perifoveal opacities. Angiographic evidence of macular edema may not unanimously correlate with presence of CME on OCT in these cases.     

Visual field constriction and electrophysiological changes associated with vigabatrin

Purpose: We investigated functional, morphological and electrophysiological changes in patients under anti-epileptic therapy with vigabatrin (VGB), a GABA aminotransferase inhibitor. Methods: 20 epileptic patients treated with vigabatrin (age range 25–66 years) were enrolled in this study. The referrals were made by the treating neurologist, based on suspected or known visual field changes in these patients. Two patients had vigabatrin monotherapy, 18 patients were treated with vigabatrin in combination with other antiepileptic drugs. None of the patients reported visual complaints. Patients were examined with psychophysical tests including colour vision (Farnsworth D15), dark adaptation threshold, Goldmann visual fields and Tuebingen Automated Perimetry (90°). A Ganzfeld ERG and an EOG following the ISCEV standard protocol were also obtained. Additionally, all patients were examined with the VERIS multifocal ERG including recordings of multifocal oscillatory potentials. Results: Visual acuity, anterior and posterior segments, colour vision and dark adaptation thresholds were normal in all patients. Of 20 patients, 18 presented visual field constriction. All patients with visual field defects revealed altered oscillatory potentials waveforms in the ERG, especially in those patients with marked visual field defects. Multifocal oscillatory potentials were also delayed in those patients. In some patients a delayed cone single flash response (6/20), a reduced mERG amplitude (12/20) and a reduced Arden ratio (9/20) were found. Conclusions: The present data indicate an effect of vigabatrin on the inner retinal layers. Since abnormalities of the oscillatory potentials were seen in all patients with visual field defects a dysfunction of GABA-ergic retinal cell transmission might be assumed.     

Visual evoked potential (VEP) and multifocal electroretinogram (mfERG) in ocular syphilitic posterior segment inflammation

The aim of this study is to correlate multifocal electroretinogram (mfERG) and visual evoked potential (VEP) changes with visual acuity and clinical features in patients with posterior segment inflammation secondary to syphilis. A retrospective interventional case series of 4 patients with visual loss secondary to syphilitic uveitis is reported. The mfERG (P1) showed diminished amplitudes and prolonged latency in 7 affected eyes. Visual acuity rapidly improved 2 weeks after initiation of therapy. OCT demonstrated anatomical recovery at 1 month. In three patients, visual acuity was restored to 6/6 at 6–9 months but mfERG responses remained significantly reduced and delayed for 12–15 months before recovery to normal levels. One patient developed a retinal detachment, but achieved 6/9 vision at 30 months. VEP changes, interpreted in combination with mfERG responses, showed evidence of optic nerve involvement in 6 eyes. Ocular findings, including posterior placoid chorioretinitis, are important diagnostic features of secondary and tertiary syphilis. Visual acuity and clinical recovery occur early with appropriate diagnosis and treatment, and precede full electrophysiological recovery of the outer retina-RPE complex. Ophthalmologists have the opportunity to play a key role in undetected or missed diagnoses of syphilis, and with appropriate treatment the visual prognosis is excellent.     

The value of multifocal ERG in diagnosis of discrete macular dystrophies

BACKGROUND: Multifocal ERG is being extensively applied to numerous retinal disorders. It has gained particular clinical value in retinal disorders developing without morphological alterations. PATIENTS AND METHODS: We investigated a series of 4 patients, aged 10, 18, 29, and 49 years, respectively. When examined, they complained of photophobia and slowly progressive bilateral loss of vision, visual acuity ranging from 0.7 to 0.1. RESULTS: Ophthalmoscopic examination showed no or minimal alterations such as subtle granular changes in the fovea. Photopic-scotopic full-field ERG was normal. Multifocal ERG, in contrast, showed markedly reduced signal amplitudes within the central 10 degrees. CONCLUSIONS: Based on the results of multifocal ERG, we were able in each case to consider with a high degree of probability the diagnosis of progressive foveal cone dystrophy. This is to emphasize the sensitivity of multifocal ERG in disorders affecting primarily the macula, without morphological changes, as cone (-rod) dystrophy, early Stargardt dystrophy, etc. The uttermost advantages of multifocal ERG are its innocuity, its applicability to children and the very early sensitivity to changes in retinal function.     

A case of localized retinal damage in thallium poisoning

Purpose: To determine the cause of visual impairment and to document the late eye disturbances in a case of thallium poisoning. Patient: A 44-year-oldwoman presented with a history of repeated attacks of complete alopecia over a period of several months, diffuse pain in both legs, transient gastrointestinal disturbances, abasia with a progressive paraparesis, paresthesia in the fingertips, and polyneuropathy. She complained of slowly progressive visual deterioration in both eyes which began about six months after the first attack of alopecia. The optic discs showed distinct signs of temporal atrophy together with a deep temporal excavation. The Goldmann perimetry revealed an absolute central scotoma. Traces of thallium were found in the urine and in the serum. The district attorney later discovered that her husband had been trying to poison her with thallium. Methods: The clinical and electrophysiological examinations included visual evoked potentials (VEP) and electroretinography (flash ERG, multifocal ERG and pattern ERG). Results: The VEP showed a reduction in amplitude and a prolonged latency indicating a conduction block. The pattern ERG was initially normal. At a follow-up examination 6 years later, a slight amplitude reduction in the pattern ERG was found. The multifocal ERG showed a diminished amplitude in the center of the retina (up to± 10° visual angle). Conclusions: The electrophysiological investigations in our patient – who had an optic atrophy – indicated a conduction block of the retinal nerve fibers (VEP) and an additional lesion at or before the retinal bipolar cells (multifocal ERG),localized in the central ± 10°. These findings suggest that thallium poisoning can lead to a combined lesion of the retinal nerve fibers and the neural retina. This revised version was published online in August 2006 with corrections to the Cover Date.     

RDH12-associated retinal degeneration caused by a homozygous pathogenic variant of 146C>T and literature review

AIM: To describe the clinical, electrophysiological, and genetic features of an unusual case with an RDH12 homozygous pathogenic variant and reviewed the characteristics of the patients reported with the same variant. METHODS: The patient underwent a complete ophthalmologic examination including best-corrected visual acuity, anterior segment and dilated fundus, visual field, spectral-domain optical coherence tomography (OCT) and electroretinogram (ERG). The retinal disease panel genes were sequenced through chip capture high-throughput sequencing and Sanger sequencing was used to confirm the result. Then we reviewed the characteristics of the patients reported with the same variant. RESULTS: A 30-year male presented with severe early retinal degeneration who complained night blindness, decreased visual acuity, vitreous floaters and amaurosis fugax. The best corrected vision was 0.04 OD and 0.12 OS, respectively. The fundus photo and OCT showed bilateral macular atrophy but larger areas of macular atrophy in the left eye. Autofluorescence shows bilateral symmetrical hypo-autofluorescence. ERG revealed that the amplitudes of a- and b-wave were severely decreased. Multifocal ERG showed decreased amplitudes in the local macular area. A homozygous missense variant c.146C>T (chr14:68191267) was found. The clinical characteristics of a total of 13 patients reported with the same pathologic variant varied. CONCLUSION: An unusual patient with a homozygous pathogenic variant in the c.146C>T of RDH12 which causes late-onset and asymmetric retinal degeneration are reported. The clinical manifestations of the patient with multimodal retinal imaging and functional examinations have enriched our understanding of this disease.     

Amiodarone treatment and visual prognosis

BACKGROUND: Amiodarone is currently regarded as the most effective antiarrhythmic drug available for the treatment of tachyarrhythmias. Up to now, no recommendations exist concerning ophthalmological follow-up examinations at regular intervals of patients treated with amiodarone. METHODS AND PATIENTS: We examined six patients with a mean age of 71.7 years (five men, one woman) who were treated with amiodarone. RESULTS: One patient had no visual disturbances and a second patient had no permanent change of the optic nerve because treatment with amiodarone was discontinued in time. In one patient an abnormal blue colour vision was noticed. Swelling of the optic disc completely disappeared in five patients after discontinuing the drug. One patient revealed a posterior ischaemic optic neuropathy (PION). In two patients a unilateral change of the optic disc occurred. In three patients a severe irreversible lesion of the optic nerve was found at follow-up examination. CONCLUSIONS: An insidious visual loss can occur with amiodarone treatment. A swelling of the optic disc without visual deterioration can occur as the first sign of a defect of the optic nerve. An abnormal blue colour vision can also be detected. After discontinuation of amiodarone either a visual improvement or a permanent deterioration may result. We recommend that every patient being treated with amiodarone should be observed by opthalmoscopy and colour vision examination at regular intervals (approximately every 3 months). Treatment with amiodarone should be discontinued after exclusion of life-threatening situations by a cardiologist, as soon as the first changes of the optic disc occur.