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

Acute Macular Neuroretinopathy in Purtscher Retinopathy

Purtscher retinopathy and acute macular neuroretinopathy are two rare clinical disorders that are both probably associated with ischemic pathogenesis. In this report, we describe for the first time the coexistence of Purtscher retinopathy and acute macular neuroretinopathy in a patient with visual complaints after chest trauma. Optical coherence tomography (OCT) scans demonstrated outer retinal defects, while OCT angiography illustrated areas of hypoperfusion in the superficial and deep capillary plexuses as well as the choriocapillaris. In this report, it is emphasized that acute macular neuroretinopathy is a clinical condition that should be kept in mind in patients presenting with post-traumatic vision loss. Although its clinical diagnosis is difficult, characteristic OCT and OCT angiography findings facilitate diagnosis.

Bilateral Acute Macular Neuroretinopathy in a Young Patient: Imaging and Visual Field during Two-Year-Follow-Up

Acute macular neuroretinopathy (AMN) is a rare disorder. We report a case of bilateral AMN in a young female patient, without any risk factors. She referred a positive scotoma in both eyes after flu-like symptoms. Fundus examination revealed parafoveal dark-reddish oval lesions in both eyes. Therefore, we performed visual field, optical coherence tomography (OCT), fluorescein angiography (FA) and indocyanine green angiography (ICG) at baseline and several times during the two years of follow-up. The infrared (IR) imaging showed one rounded hyporeflective lesion in the left eye and two similar lesions in the right eye. The OCT demonstrated the characteristic alterations in the outer retina. The visual field also demonstrated scotomas corresponding with these lesions. The OCT and IR features disappeared at the end of the follow-up except for the left eye, which continued to have hyperreflective spots in the outer plexiform layer. The patient complained about a residual scotoma only in the left eye after two years. Our case shows a difference in disease progression in the two eyes of the same patient, suggesting that several mechanisms can be implicated in the pathology of AMN.

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY OF ACUTE MACULAR NEURORETINOPATHY REVEALS DEEP CAPILLARY ISCHEMIA

PURPOSE

To present the multimodal retinal imaging findings, including optical coherence tomography (OCT) angiography, of an atypical case of acute macular neuroretinopathy (AMN).

METHODS

The multimodal retinal imaging findings, including structural OCT and OCT angiography, of an atypical case of AMN are presented.

RESULTS

A 23-year old woman, with a history of an unrelenting sinusitis treated with prednisone therapy and decongestants, presented with an acute scotoma of the right eye. Structural OCT illustrated an area of hyperreflectivity in the outer plexiform and outer nuclear layers nasal to the fovea, with associated disruption of the inner segment ellipsoid band consistent with AMN. At the 2-week follow-up visit, intraretinal fluid was noted with repeat OCT, with spontaneous resolution of the fluid at the 2-month follow-up visit. Optical coherence tomography angiography illustrated a flow void in the deep retinal capillary plexus associated with the AMN lesion.

CONCLUSION

Atypical findings of AMN are presented in this case report including the presence and spontaneous resolution of intraretinal fluid. Although OCT angiography illustrated a flow deficit within the deep retinal capillary plexus, the cause of AMN remains elusive.

CILIOCHOROIDAL EFFUSION AND ACUTE MACULAR NEURORETINOPATHY ASSOCIATED WITH CERVICAL TRACTION THERAPY

PURPOSE

To report an unusual case of ciliochoroidal effusion and presumed acute macular neuroretinopathy associated with cervical traction therapy for the treatment of cervical spinal stenosis.

METHODS

Case report.

RESULTS

A 75-year-old man reported sudden onset of a wedge-shaped paracentral scotoma in the right eye. Fundus examination showed a ciliochoroidal effusion in the right eye. Optical coherence tomography revealed intraretinal fluid in both eyes without leakage on fluorescein angiography. B-scan ultrasonography and anterior segment ultrasound biomicroscopy of the right eye showed peripheral ciliochoroidal effusion. He had recently started intensive cervical traction therapy for the treatment of cervical spinal stenosis. There was spontaneous resolution of the choroidal effusion and intraretinal fluid after stopping cervical traction treatments. Optical coherence tomography imaging after resolution of the intraretinal fluid revealed thinning of the outer nuclear layer and attenuation of the ellipsoid and interdigitation zones corresponding to a persistent paracentral scotoma, consistent with acute macular neuroretinopathy.

CONCLUSION

This is the first report of adverse ocular effects of cervical traction. We postulate that venous and arterial compromise during cervical traction therapy resulted in both ciliochoroidal effusion and a watershed infarct in the outer retina.

ACUTE MACULAR NEURORETINOPATHY WITHOUT NEAR-INFRARED REFLECTANCE-AN ATYPICAL CASE PRESENTATION

BACKGROUND

Acute macular neuroretinopathy is a rare disease that with the help of multimodal imaging is being diagnosed more frequently.

METHODS

An atypical case is presented and followed by multimodal imaging.

RESULTS

A typical acute macular neuroretinopathy lesion was seen on biomicroscopic examination and spectral domain optical coherence tomography examination. However, near-infrared imaging revealed a lack of the characteristic finding along with a relative afferent pupillary defect and a widespread depressed multifocal electroretinogram which has not been reported previously.

CONCLUSION

This patient exhibits photoreceptor and outer retinal findings commonly described in acute macular neuroretinopathy lesion without classic near-infrared findings. This case may represent a severe form of acute macular neuroretinopathy.

Quantification of retinal layer thickness changes in acute macular neuroretinopathy

Purpose

To quantitatively evaluate retinal layer thickness changes in acute macular neuroretinopathy (AMN).

Methods

AMN areas were identified using near-infrared reflectance (NIR) images. Intraretinal layer segmentation using Heidelberg software was performed. The inbuilt ETDRS -grid was moved onto the AMN lesion and the mean retinal layer thicknesses of the central grid were recorded and compared with the corresponding area of the fellow eye at initial presentation and during follow-up.

Results

Eleven patients were included (mean age 26±6 years). AMN lesions at baseline had a significantly thinner outer nuclear layer (ONL) (51±21 µm vs 73±17 µm, p=0.002). The other layers, including inner nuclear layer (37±8 µm vs 38±6 µm, p=0.9) and outer plexiform layer (OPL) (45±19 µm vs 33±16 µm, p=0.1) did not show significant differences between the study eyes and fellow eyes. Adjacent to NIR image lesions, areas of OPL thickening were identified (study eye: 50±14 µm vs fellow eye: 39±16 µm, p=0.005) with corresponding thinning of ONL (study eye: 52±16 µm vs fellow eye: 69±16 µm, p=0.002).

Conclusions

AMN presents with characteristic quantitative retinal changes and the extent of the lesion may be more extensive than initially presumed from NIR image lesions.