Dome-Shaped Macula and Foveal Neurosensory Retinal Detachment—A Case Series

Objective: To report a case series of dome-shaped macula (DSM) and serous retinal detachment (SRD). Methods: A retrospective and observational case series study was performed at two centers of ophthalmology in Rosario-Argentina from January 2016 to December 2017. Eight eyes of 5 patients diagnosed with dome-shaped macula with subfoveal hyporeflective zone seen in optical coherence tomography (OCT) were included. Best-corrected visual acuity (BCVA), OCT, fluorescein angiography (FA), differential diagnoses, clinical course and different treatments were reviewed. Results: Baseline visual acuity ranged from 20/25 to 20/200. OCT revealed that the retinal choroidal macular complex had a convex shape and exhibited foveal neurosensory retinal detachment in all cases. FA showed mild diffuse hyperfluorescence due to changes in the retinal pigment epithelium (RPE). No sign of leakage was observed. Different treatments were used, including intravitreal antiangiogenic drugs, oral spironolactone, melatonin and observation. Follow-up time was between 6 and 18 months. BCVA and OCT findings remained unchanged after different options of treatment. Conclusions: DSM is an unusual entity, which can be confused with other maculopathies that cause neurosensory retinal detachment and do not respond to different types of treatment. Hence, in our opinion, observation is a reasonable approach for this disorder.

ing characterized by an inward convexity of the macula within the concavity of the posterior staphyloma occurring in highly myopic patients [1].
Serous retinal detachment (SRD) without choroidal neovascularization is a well-known complication of DSM and it is rarely reported in the absence of DSM [4]. While its physiopathological mechanism is still unknown, different theories have been proposed and include a thickening of the choroid [1] or a subfoveal scleral thickening that affects the flow of choroidal fluid [5].
Achieving a diagnosis of SRD associated with DSM can be challenging because it should be differentiated from other conditions associated with subretinal fluid (SRF) in the macular area, such as myopic CNV, idiopathic central serous chorioretinopathy, neovascular age-related macular degeneration (ARMD), polypoidal choroidal vasculopathy and tilted disc syndrome.
Because its pathophysiology is still unclear, no treatment has been identified.
Few reports describing the successful treatment of SRD associated with DSM have been published, and the results reported in different reports have been variable. Some articles describe spontaneous resolution [6], while others describe treatment with half-fluence photodynamic therapy [7], argon laser photocoagulation, spironolactone [8] [9] and intravitreal antiangiogenic therapy [10].
Recently, some retrospective studies found that DSM is a condition that seems to remain stable over time even when is associated to chronic SRD [11] [12] in contrast to previous reports [13].
The objective of this study is to present five cases of DSM with SRD, including their refractive characteristics, clinical courses and the lack of successful results following a variety of therapeutic attempts.

Methods
A retrospective review of 8 eyes in 5 patients was conducted at two centers of ophthalmology in Rosario-Argentina from January 2016 to December 2017. The patients had been referred to us for diagnosis of visual complains or imaging of suspected fundus anomalies diagnosed in routine examination.
We analysed the following: BCVA using standard Early Treatment Diabetic Retinopathy Study (ETDRS) charts, refractive error, unilateral or bilateral DSM associated or not associated with SRD, spectral domain OCT and fluorescein angiography (FA) images, clinical course and treatments performed.
Dome-shaped macula was defined as a convexity of the retina-choroidal macular complex seen on spectral domain OCT images. In all patients, we achieved a diagnosis of DSM configuration based on spectral domain OCT (SD-OCT) images with vertical and horizontal scan patterns according to the description of Gaucher. SRD was defined as the hyporeflective subfoveal zone. Subfoveal choroidal thickness (SFCT) was measured with EDI-OCT (Spectralis, Heidelberg Engineering, Heidelberg, Germany) and was defined as the distance from the outer edge of the hyperreflective line corresponding to the RPE to the inner surface of the sclera. Increased SFCT was defined as measurement > 350 micras [14].
The patients received different treatments, including spironolactone, intravitreal anti-VEGF, melatonin and observation. Details of each case are reported in the case report section.
This report was conducted in accordance with the Helsinki Declaration, and informed consent was obtained from patients, consistent with our institutional guidelines.

Results
We included 8 eyes in 5 patients with DSM and SRD confirmed by OCT. There were four female patients and one male patient. Age was ranged between 29 to 68 years.
Refractive error was high myopia (>6D) in 4 eyes, low myopia (<6D) in 2 eyes and hypermetropia in 2 eyes. All patients had a bilateral configuration of DSM, but 3 of them presented bilateral SRD associated and two were unilateral.  Table 1 showed data of five patients included in the study (Table 1).     anti-VEGF treatment was observed. This patient was followed up for 18 months and remained stable. 5) Case 5: A 61-year-old patient being treated with topiramate came to the clinic due to bilateral maculopathy. BCVA was 20/25 in OD (+2: −2.5 × 85˚) and 20/30 in the OS (+1.25: −2.5 × 70˚). Fundoscopy showed posterior staphyloma and pigmentary changes at the macular area in the OU. An inferior parapapillary retinochoroidal coloboma was observed in the OS. OCT confirmed DSM with a subfoveal hyporeflective zone in the OU, and early hyperfluorescence without leakage points was observed on FA ( Figure 3). She remained under observation and there were no changes in BCVA or OCT findings during 18 months of follow-up.

Discussion
DSM was initially described in myopic patients. In 2015, Liang reported the largest series of cases, in which 225 eyes with DSM were identified out of 1118 eyes with high myopia (20%). [15] However, the last analysis of this data has revealed that DSM can occur in patients with moderate myopia, emmetropia and even hypermetropia. [11] This is consistent with our case series, in which one of the patients with DSM had low myopia and one had hypermetropia.
The most frequent complication of DSM is the presence of SRD. Its prevalence ranges from 28.5% to 66.6%. However, the presence of subretinal fluid (SRF) was not associated with vision loss in comparison to patients without SRD [11] [12].
The cause of SRD is not known. Various hypotheses have been suggested.
Imamura et al. proposed that SRD may be the result of an obstruction in the choroidal blood flow due to a thickening of the sclera, similar to the mechanism underlying uveal effusion in nanophthalmic eyes [5]. with antiangiogenic drugs and photodynamic therapy and those who did not [11].
The relationship between SRD and macular atrophy is also variable. While some studies that demonstrated that macular atrophy increases progressively and that it is related to the height of the macular bulge, [8] [16] others did not find any differences between cases with and without SRD based on the size of atrophy [4]. DSM is a rare entity, and its pathophysiology and treatment approach are not clear. In this study, all patients presented an increase in choroidal thickness measured by SD-OCT, this can be the result of a choroidal fluid disturbance produced by the thickened scleral in the dome-shaped area.
We agree that the pathophysiological mechanism in DSM with SRD is similar to that observed in CSC. However, in this review, no points of leakage were observed in any case. In our opinion, this disorder may manifest as active and inactive phases over time.
Differential diagnosis includes other maculopathies that present with neurosensory retinal detachment. The main differential diagnoses are central serous chorioretinopathy (CSC), myopic CNV and choroidal hemangioma [17] [18]. Another disorder to consider in high myopia associated with SRD is tilted disc.
This study has various limitations. It had a small sample size, a retrospective design, and a short follow-up period, and no scleral measurements were obtained.

Conclusion
In this case series, consistent with the reviewed literature, DSM patients present a stable evolution and do not respond to different types of treatment. In our opinion, this makes observation a good alternative.