Berlin’s Edema with Atypical Optical Coherence Tomography Findings: A Case Report

Abstract

Berlin’s edema is an acute traumatic maculopathy following ocular blunt trauma, with the major site of injury is photoreceptor outer segments and retinal pigment epithelium (RPE). Optical coherence tomography (OCT) is a useful tool to diagnose and follow microstructural changes in Berlin’s edema. In this report, we present an atypical case of Berlin’s edema that resembled Vogt-Koyanagi-Harada disease. OCT demonstrated multiple neurosensory detachments and giant cystic changes of the outer retina. Fluorescein angiography showed no dye leakage or vascular alterations. The patient was treated with a short period of topical and systemic corticosteroids, and she improved significantly within a few weeks.

Introduction

Commotio retinae is a retinal contrecoup injury following ocular blunt trauma. It may involve the central or peripheral retina, and when it occurs centrally, it is known as Berlin’s edema. While mild cases may resolve spontaneously with no or minimal sequelae in a few days to weeks, severe ones may progress to further sight-threatening complications such as choroidal rupture, macular hole, etc.

Increased reflectivity of photoreceptor outer segments and increased thickening of the outer retina are the most frequent findings of optical coherence tomography (OCT) [1–4]. Herein, we report a patient with Berlin’s edema who exhibited atypical OCT findings.

Case Report

A 45-year-old housewife presented to our clinic with a complaint of sudden loss of vision in the right eye following ocular blunt trauma from a thrown hanger, happened 4 days earlier. She had no history of underlying disease or previous ocular surgery. Her family and drug histories were both negative.

A comprehensive ophthalmic examination was conducted and revealed that the best corrected visual acuity was 7/100 and 10/10 in her right and left eyes, respectively. The RAPD was negative. The fundus biomicroscopy of the right eye revealed thickening and white-grayish discoloration of the macula with subretinal fluid but without any bleeding or vascular alterations (see Fig. 1a). No other ocular injuries were evident.

Fig. 1.

a The fundus photo of the right posterior pole at presentation shows macular elevation, white-grayish discoloration of the macula, and diminished foveal reflex, with no bleeding, vascular alterations, or optic nerve head abnormalities. The macular edema appears with white concentric lines. b The fundus photo of the right posterior pole taken 3 weeks later shows resolved opacification of the retina, leaving mottling of retinal pigmented epithelium (RPE) in the affected area.

Spectral domain optical coherence tomography (SD-OCT) (OCT Spectralis, Heidelberg Engineering, Germany) revealed a significant increase in the central macular thickness (985 µm), hyper-reflectivity of the inner layers of the retina with preserved architecture, giant cystic changes in the outer layers along with multiple neurosensory retinal detachments (NSD) (see Fig. 2a, b). Due to significant intraretinal and subretinal cystic changes, the presence of an underlying vascular versus inflammatory pathology was suspected. Hence, the patient was subjected to additional paraclinical examinations to evaluate Harada disease, central serous chorioretinopathy, acute macular neuroretinopathy, and acute idiopathic maculopathy.

Fig. 2.

a, b The horizontal macular OCT scans of the right eye taken at presentation show significant macular thickening, hyper-reflectivity of the inner retina (red arrow) with preserved architecture, giant intraretinal (asterisks) and subretinal (white arrow) pseudo-cystic changes along with multiple neurosensory retinal detachments (NSD) are indicated (arrowheads). c The horizontal macular OCT scan of the right eye taken 3 weeks later shows complete resolution of intra- and subretinal edema, with the retina appearing atrophic. The reflectivity of the retinal layers was subnormal, and the outer layers were slightly attenuated (yellow arrow). d The horizontal macular OCT scan of the right eye taken 6 months later shows surprising regeneration of the retinal outer layers, with slight residual attenuation of photoreceptors (pink arrow).

Enhanced Depth Imaging OCT Showed No Dilatation or Pachychoroid Appearance

Fundus autofluorescence imaging indicated hypoautofluorescence corresponding to the edematous and opaque macula (see Fig. 3a). Additionally, the fluorescein angiography demonstrated the macular hypofluorescence secondary to blockage from macular thickening and opacification. No evidence of dye leakage in the retina or optic nerve head, vessel wall staining, or other vascular alterations was found (see Fig. 3b–d).

Fig. 3.

a The fundus autofluorescence image of the right eye shows blocked autofluorescence corresponding to the edematous and opaque macula. b–d The fluorescein angiography of the right eye shows the macular hypofluorescence corresponding to the macular edema blockage, with no evidence of dye leakage in the retina, optic nerve head, vessel wall staining, or other vascular alterations.

After being diagnosed with Berlin edema, the patient was treated with betamethasone eye drops (Betasonate 1%, Sina Darou, Iran) four times daily and prednisolone 50 mg (Nisopred 50 mg TAB, Iran Hormone, Iran) daily. Three weeks later, the patient’s vision improved to 4/10, and the opacification of the retina was resolved, leaving mottling of retinal pigmented epithelium (RPE) in the affected area (see Fig. 1b).

In the SD-OCT, the retina was found to be atrophic and the intra- and subretinal edema were completely resolved. The central thickness of the macula decreased to 185 microns, and the reflectivity of the retinal layers was subnormal. Additionally, the ellipsoid zone was slightly attenuated (see Fig. 2c).

Due to the risk of complications, including macular hole, the patient was regularly followed up. During the 6-month follow-up, the patient’s vision improved to 10/10, and the SD-OCT showed surprising regeneration of the retinal outer layers (see Fig. 2d).

The study adheres to the tenets of the Declaration of Helsinki, and informed consent was obtained from the patient to publish her data. The CARE Checklist has been completed by the authors for this case report, attached as online supplementary material (for all online suppl. material, see https://doi.org/10.1159/000533886).

Case Discussion

Berlin’s edema, first described as commotio retinae by Berlin in 1873 in a patient with ocular blunt trauma, is an acute traumatic maculopathy [5], characterized by disruption of photoreceptor outer segments and damage to RPE [6]. The severity and extension of edema depend on the severity of the trauma.

The pathogenesis of Berlin’s edema is not completely understood, but it is hypothesized that rapid deceleration of ocular tissues and transmission of blunt force to the retina lead to disruption of the blood-retinal barrier [7]. However, other researchers have found evidence to contradict this hypothesis. For instance, vitreous fluorophotometry revealed no statistically significant differences in posterior vitreous dye penetration between the involved and uninvolved eyes. Moreover, the fluorescein angiographies demonstrated no leakage in either eye, making it unlikely that breakdown of the blood-retinal barrier plays a major pathophysiological role [7].

It is suggested that retinal opacification in Berlin’s edema is the result of swollen nerve fibers, Müller cells, and disrupted RPE and photoreceptor outer segments [8]. Loss of vision occurs as a consequence of permanent loss of these photoreceptors [6, 8]. It is hypothesized that hydraulic forces stretch the neuroretina at the level of the outer segments, while intact Müller cells hold the rest of the retina together [2, 9]. Commotio retinae is a result of impairments of intracellular structures with no extracellular edema. Edematous inner segments with mitochondrial calcium deposits may demonstrate increased permeability of the plasma membranes [2]. Following a blunt trauma, vitreoretinal attachments can exert mechanical contrecoup distortion of the retina [2]. The intact Müller foot processes appear to be responsible for preserved neuro-retinal architecture, up to the level of the photoreceptors. An uncommon hyper-reflective inner retinal band possibly indicates the photoreceptor inner segments, with less reflective outer segments underneath and in the subretinal space [2]. Impaired outer segments are phagocytosed by RPE and restored, leading to central vision improvement within weeks [6].

Compared to other imaging methods, OCT is a valuable tool in the evaluation of patients with posterior segment trauma, especially in acute traumatic maculopathy, as it is noninvasive and comfortable [10]. Different OCT findings have been described in Berlin’s edema, including increased reflectivity due to photoreceptor outer segment disruption [1–4] and, less commonly, hyper-reflectivity of inner retinal layers [3]. Other findings include outer retinal thickening, a low signal triangular area below the foveal pit, and increased central retinal thickness [10]. Fragmentation of the inner segment/outer segment layer [11], disruption of retinal pigment epithelium interdigitation associated with intraretinal edema of the outer nuclear layer [12], neurosensory retinal detachment (NSD) [2, 10], and increased reflectivity of the line at the junction between the photoreceptor inner and outer segments in the healing phase have also been reported in Berlin’s edema [13]. Recently, OCTA has exhibited foveal avascular zone enlargement in both the superficial and deep capillary layers [14].

In our patient, a significant macular thickening (985 μm) and apparently hyper-reflective inner retina with preserved architecture were observed. Additionally, giant cystic changes in the outer retina along with multiple NSD were present in an atypical way that raised suspicion of pathologies other than traumatic maculopathy. However, further investigations ruled out any underlying vascular or inflammatory etiologies. Fluorescein angiography also ruled out any signs of active leakage, making it less probable that blood-retinal barrier breakdown played a major role in the pathophysiology of Berlin’s edema.

Although different reported cases of Berlin’s edema have resulted in similar clinical outcomes, the involved layers of the retina have shown slight variations, possibly due to differences in the nature and severity of the injury [1–4, 10, 13]. It is suggested that the greater the severity of the trauma, the more severe the imaging findings are likely to be. Despite our patient’s history of being hit by a thrown hanger with low intensity, her clinical and OCT manifestation were surprisingly remarkable.

Berlin’s edema has been reported to resolve almost completely [1, 8]. The disruption limited to the photoreceptor outer segments mostly improves, while, in more severe trauma, when the inner segments of the photoreceptors are also damaged, cellular necrosis and consequent atrophy of the fovea can be expected [6]. However, persistent vitreoretinal traction can lead to Müller cell degeneration and consequent chronic cystoid macular edema and macular holes [4]. Moreover, Berlin’s edema may be accompanied by choroidal infarction (Hutchinson-Siegrist-Neubauer syndrome), choroidal rupture, or choroidal neovascularization [15].

Due to the high potential for uncomplicated improvement, most patients with Berlin’s edema are followed up conservatively. However, some ophthalmologists experimentally use steroids, either topically or systemically, to speed up the recovery process. In our case, the patient was treated with topical and oral steroids for 2 weeks. Despite the initially vigorous manifestations, both anatomically and functionally, the patient completely recovered in a period of 6 months. However, the role of steroids in treatment of Berlin’s edema cannot be conclusively determined due to the lack of controlled studies.

Conclusion

OCT is a useful modality for diagnosing ultrastructural macular alterations in eyes with Berlin’s edema. Atypical presentations of severe Berlin’s edema, such as Vogt-Koyanagi-Harada-like manifestations in OCT, can occur. Despite the initially vigorous clinical and OCT manifestations, Berlin’s edema can improve surprisingly. However, precise and regular follow-up visits are warranted to diagnose and manage possible complications. Further trials are required to stablish the role of steroids in accelerating recovery and regeneration of outer retinal layers and preventing scarring in patients with severe Berlin’s edema.

Statement of Ethics

The study adheres to the principles outlined in the Declaration of Helsinki. Written informed consent was obtained from the patient for publication of the details of her medical case and accompanying images. Ethical approval was not required for this study in accordance with national guidelines.

Conflict of Interest Statement

The authors have no conflicts of interest to declare.

Funding Sources

This study is not funded.

Author Contributions

N.K. and H.N. contributed to data gathering, drafting, and approval of the manuscript. F.Y. gathered the data and approved the final manuscript.

Funding Statement

This study is not funded.

Data Availability Statement

All data generated or analyzed during this study are included in this article. Further inquiries can be directed to the corresponding author.