Optical coherence tomography findings in acute macular neuroretinopathy

Acute Macular Neuroretinopathy Following Non-Ocular Trauma: A Hypothesis Regarding Pathophysiologic Mechanism

BACKGROUND AND OBJECTIVE

To describe the imaging characteristics and clinical course of acute macular neuroretinopathy (AMN) following non-ocular trauma, and to hypothesize a pathophysiologic mechanism for this syndrome.

PATIENTS AND METHODS

The records of five patients who developed symptoms and findings suggestive of AMN following trauma to the face or chest were retrospectively reviewed. Optical coherence tomography (OCT), infrared reflectance, fundus autofluorescence, fluorescein and indocyanine green angiography, and multifocal electroretinography were evaluated.

RESULTS

Visual symptoms started immediately or very soon after non-ocular trauma, and scotomas persisted at last follow-up (2 weeks to 10 years after trauma). OCT imaging performed within days of the trauma demonstrated focal areas of hyper-reflectivity in the outer plexiform and outer nuclear layers with eventual thinning of the outer nuclear layer, as well as variable loss of the ellipsoid and interdigitation zones.

CONCLUSION

Acute ischemic injury caused by trauma-induced hypotension and/or catecholamine release and involving the deep retinal capillary plexus is the pathogenic mechanism that most plausibly explains trauma-associated AMN.

[Acute macular neuroretinopathy]

A 24-year-old female patient presented with sudden onset of paracentral visual field defects of the right eye, which were noticed 2 months before the clinical examination. The slit lamp examination of the anterior and posterior segments showed unremarkable findings but three oval, well demarcated, hyporeflective areas were noticed in the right posterior pole in infrared fundus photographs. A similar small area was found in the left posterior pole. Optical coherence tomography (Cirrus OCT) showed a structural defect of the hyperreflective bands of the outer retina. The diagnosis of acute macular neuroretinopathy was made.

Outer retinal abnormalities in acute macular neuroretinopathy

PURPOSE

To investigate the spectral-domain optical coherence tomography findings in four cases of acute macular neuroretinopathy and identify features that may differentiate acute macular neuroretinopathy from similar conditions in the acute zonal occult outer retinopathy complex.

METHODS

Patients with acute macular neuroretinopathy underwent complete periodic examinations, including ophthalmoscopy, color photography and autofluorescence photography, visual field testing, and spectral-domain optical coherence tomography. Abnormalities as seen by multimodal imaging were documented and evaluated during follow-up.

RESULTS

The average age of the 4 patients was 32 years (range, 28-34 years), and 2 had bilateral involvement. The follow-up ranged from 1 month to 5 months. In each patient, dark lobular areas seen by ophthalmoscopy corresponded to the measured visual field defect and what appeared to be a regional loss of outer segments of the photoreceptors. The outer segment defect resolved in two patients and improved in the other two during follow-up. All patients showed a colocalizing regional thinning of the outer nuclear layer, which did not change during the follow-up period. There were no associated abnormalities in the fundus appearance.

CONCLUSION

Acute macular neuroretinopathy causes reddish brown patches that are because of outer retinal damage as documented by spectral-domain optical coherence tomography. Unlike other entities in the acute zonal occult outer retinopathy complex, acute macular neuroretinopathy has no other synchronic ophthalmoscopically visible fundus abnormalities. These lesions may resolve over time, with restoration of the outermost retinal architecture, but persistent thinning of the overlying outer nuclear layer remained.

Acute macular neuroretinopathy: contribution of spectral-domain optical coherence tomography and multifocal ERG

BACKGROUND

Acute macular neuroretinopathy is a rare disease which occurs in young women and causes sudden paracentral scotoma and typical reddish-brown macular lesions.

MATERIAL AND METHODS

We report two cases of young women suffering from acute macular neuroretinopathy which we observed with spectral-domain Spectralis HRA-OCT and multifocal ERG at 3 and 7 months.

RESULTS

Imaging revealed an early hyper-reflectivity of the photoreceptor layer, which changed into hyporeflectivity in the first week and remained the same in the following months, whereas visual field improved.

CONCLUSIONS

Our findings show involvement primarly of the outer retina, and confirm OCT and mf ERG as important tools for diagnosis and follow-up of pathologic changes in AMNR, as other diagnostic tests often remain normal.

Visualization and follow-up of acute macular neuroretinopathy with the Spectralis HRA+OCT device

BACKGROUND

Acute macular neuroretinopathy (AMNR) is a rare disease entity, the diagnosis of which is frequently complicated by the subtlety of biomicroscopic findings.

METHODS

Two cases of AMNR are presented, in which the diagnosis and follow-up was enabled using the Spectralis HRA+OCT in the absence of clear biomicroscopic findings.

RESULTS

The typical lesions were visualized by hyporeflexion during infrared imaging and faded over time. With spectral domain optical coherence tomography, changes in the outer retina in the affected regions were documented, with no change over time.

CONCLUSION

The broader availability of this technology may enhance the diagnosis and follow-up of AMNR.

Two cases of acute macular neuroretinopathy

PURPOSE

To report chorioretinal vasoconstriction as a potential pathogenic mechanism in acute macular neuroretinopathy (AMNR). To describe a time lag between the onset of functional deficits and that of fundoscopically visible lesions and illustrate the superior value of infrared (IR) compared to red-free or white light imaging in AMNR.

METHODS

Two young female patients (30 and 19 years old) with AMNR are described. Both underwent detailed clinical examination with additional imaging using IR, blue, and red-free light. Functional evaluation with pattern and multifocal electroretinography, Goldmann manual, and automated Humphrey visual fields (VFs) was also performed.

RESULTS

The first patient was diagnosed with AMNR after a caesarian section during and after which she received treatment with vasoconstrictive drugs. She was followed up for 28 months, after which time she still suffered from bilateral U-shaped paracentral scotomata associated with macular lesions. The second patient complained of central scotomata prior to the onset of any visible fundoscopic lesions, following a bout of flu. VFs confirmed a central scotoma and pattern electroretinography was consistent with loss of macular function. Bilateral petaloid lesions became visible after 3 days when function began to improve. In both patients IR imaging was superior to standard red-free and white light in identifying macular lesions.

CONCLUSIONS

Vasoconstriction in the chorioretina may be pathogenic in AMNR. Functional complaints precede fundus lesions in AMNR. And, IR light is superior to red-free or white light imaging in detecting typical fundus lesions in AMNR both early and late in the course of the disease.

Longitudinal findings of acute macular neuroretinopathy with multifocal electroretinogram and optical coherence tomography

A 34-year-old woman, with preceding flu-like febrile illness, developed acute macular neuroretinopathy in her left eye with typical reddish brown macular lesions and a dense paracentral scotoma. Her condition was evaluated with multifocal electroretinogram and optical coherence tomography in her acute and recovery phases. The findings assist ophthalmologists striving for better understanding and diagnosis of acute macular neuroretinopathy.