To describe an optical coherence tomography (OCT) sign preceding macular hole (MH) formation after pars plana vitrectomy (PPV) for rhegmatogenous retinal detachment (RRD).
Retrospective observational case series.
Patients who underwent PPV for RRD at Osaka Rosai Hospital between January 2014 and December 2017 were examined. First, the medical records of the patients who had secondary MH after RRD repair were examined, and their sequential changes of the OCT images until MH formation were evaluated. Second, the OCT findings and the medical records of all patients who underwent PPV for RRD were evaluated based on the findings of the cases of secondary MH.
Ten eyes of 10 patients who had secondary MH after PPV for RRD were enrolled. Before MH formation, all eyes had parafoveal epiretinal membrane (ERM) and a characteristic OCT sign that was termed a foveal crack sign (FCS), a hyperreflective vertical line in the foveola with a deformation of the fovea. FCS was found 255 ± 217 days after PPV for RRD, and MH developed 232 ± 171 days after FCS appearance. Furthermore, among 518 eyes that underwent PPV for RRD, FCS with parafoveal ERM was found in 3 eyes without succeeding MH after RRD repair. FCS of these 3 eyes were found 363 ± 4 days after PPV for RRD.
In all cases of secondary MH formation after PPV for RRD, FCS with parafoveal ERM was found before MH formation. This sign may predict secondary MH formation caused by ERM traction.
Ten cases of macular hole formation after vitrectomy for retinal detachment were examined.
A foveal hyperreflective vertical line was found on optical coherence tomography preceding the macular hole.
This sign was accompanied by the parafoveal epiretinal membrane.
Among 518 eyes that underwent the same surgery, only 13 eyes developed this sign.
Eyes with this sign after retinal detachment repair need a careful follow-up.
A secondary macular hole (MH) is a postoperative complication of rhegmatogenous retinal detachment (RRD) surgery. Although MH formation is reported to be a rare complication after RRD repair, the complication should be noted because it can cause severe visual loss that would require an additional pars plana vitrectomy (PPV) to close the hole. The onset time of this complication varied in previous reports, but the cases that underwent PPV for RRD tended to develop MH at a relatively late stage more than 1 year after RRD repair. , ,
The pathogenesis of MH formation after PPV for RRD described in previous reports includes the association of epiretinal membrane (ERM), cystoid macular edema (CME), macula-off RRD, recurrent RRD, and high myopia. , , , , Recent reports using optical coherence tomography (OCT) have suggested that continuous tangential traction caused by ERM is the most considerable factor for MH formation after PPV for RRD. As opposed to an MH, ERM is a common postoperative complication of PPV for RRD, which occurs in the early stage after RRD repair. , Taking into account the gaps of prevalence and onset time between these 2 complications, a clinical question arises as to which cases of patients with ERM after PPV for RRD should be monitored for MH formation in the long term.
The present study retrospectively examined sequential OCT images of eyes with MH after PPV for RRD. We report a novel characteristic OCT sign that precedes MH formation after PPV for RRD. OCT images of all patients who underwent PPV for RRD were further investigated, and we identified the progression of the cases with this sign.
Subjects and Methods
This retrospective study was conducted in accordance with the tenets of the Declaration of Helsinki and approved by the institutional review board of the Osaka Rosai Hospital. Written informed consent was obtained from all patients.
First, the sequential changes of OCT findings in all patients who developed an MH after primary PPV for RRD at Osaka Rosai Hospital between January 2014 and December 2017 were retrospectively investigated. The OCT findings were examined for the presence of a sign that could precede MH formation after PPV for RRD. Additionally, the clinical characteristics of these patients were collected from the medical records. Exclusion criteria were history of intraocular surgery, except for cataract surgery; history of trauma; combined or simultaneous MH with primary RRD; tractional RD; proliferative vitreoretinopathy; presence of any other retinal disease, except for ERM, which could affect the status of the macula; and a follow-up period less than 6 months.
Second, the OCT findings and the medical records of all patients who underwent primary PPV for RRD during the same period were also investigated. Exclusion criteria were the same as above. The natural course of a certain OCT finding which developed after PPV for RRD was examined.
Patients underwent comprehensive ophthalmic examinations at least before and 1, 3, and 6 months after PPV for RRD. Most patients were followed for 12 months or more at the clinicians’ discretion. Examinations included measurement of best-corrected visual acuity, measurement of intraocular pressure, slit-lamp biomicroscopy, fundus photography, and spectral-domain OCT (Cirrus HD-OCT; Carl Zeiss Meditec, Dublin, California) or swept-source OCT (DRI-OCT; Topcon Medical Systems, Tokyo, Japan). A swept-source OCT biometer (intraocular lens Master 500 or 700; Carl Zeiss Meditec) was used to measure the axial length of all patients before RRD surgery. Clinical data, including patient age, sex, axial length, macular status at initial surgery, best-corrected visual acuity at each visit, surgical procedure of each PPV, presence of any postoperative OCT findings, onset time of the OCT findings, and MH size were reviewed from medical records. Continuous variables were expressed as mean ± standard deviation.
Horizontal and vertical B-scan cross-sectional images were acquired in each OCT examination. All OCT images obtained before and after surgery were evaluated by 3 masked investigators (T.I., Y.I., H.N.). In this evaluation, ERM was defined as hyperreflective lines on the retina accompanied by deformation of the foveal pit, and parafoveal ERM as ERM without covering the umbo. An MH was defined as a full-thickness anatomic defect in the fovea. The minimum foveal thickness (MFT) was measured manually between the vitreoretinal interface and the retinal pigment epithelium at the thinnest point of the foveola, and the diameter of the MH was measured at the narrowest hole point in the mid-retina by using the OCT caliper function as previously reported. ,
Twenty-five gauge PPV (Constellation Vision System; Alcon Laboratories, Inc., Fort Worth, Texas) with a wide-angle viewing system (Resight; Carl Zeiss Meditec) was performed in all patients with RRD. Phacoemulsification and intraocular lens implantation were performed simultaneously at the surgeons’ discretion. A core vitrectomy and peripheral vitreous shaving under scleral indentation were performed using a vitreous cutter. Triamcinolone acetonide was used to clarify the vitreous gel and posterior vitreous membrane as needed. Internal limiting membrane (ILM) peeling using Brilliant Blue G stain (Sigma-Aldrich, St. Louis, Missouri) was performed at the surgeons’ discretion. Diathermic coagulation was performed around all retinal breaks. As much subretinal fluid as possible was then drained from the pre-existing retinal break or the break created by drainage retinotomy. After fluid-air exchange, endophotocoagulation around all retinal breaks was performed. If needed, a long-acting gas (sulfur hexafluoride or octafluoropropane) or silicon oil was injected into the vitreous cavity.
The cases which developed MH after PPV for RRD underwent additional PPV to close the hole. Removal of the residual vitreous, ERM, and ILM were performed. After fluid-air exchange, sulfur hexafluoride was injected into the vitreous cavity as a case-dependent treatment.
Ten eyes that developed an MH after PPV for RRD were enrolled in this study. Figure 1 shows the sequential morphological changes of the representative case ( Figure 1 , Case 5) up to MH formation after PPV for RRD. Before MH formation, a hyperreflective vertical line in the foveola with a deformation of the fovea was found ( Figure 1 , D). The authors named this OCT finding the foveal crack sign (FCS). Table 1 summarizes the OCT findings in the 10 patients up to the MH formation. Swept-source OCT was used in 8 patients (80%). Regardless of the type of OCT, FCS was observed as a hyperreflective line at the umbo in all cases ( Figure 2 ), and parafoveal ERM had developed by the time FCS appeared in all cases. This sign was found 255 ± 217 days after PPV for RRD, and the mean interval from FCS appearance to MH diagnosis was 232 ± 171 days. The OCT images between FCS appearance and MH formation could be obtained in 3 of 10 eyes ( Table 1 , Cases 2, 5, and 6), and the MFT decreased before MH formation in all 3 cases. The mean diameter of an MH was 135 ± 34 μm.
|Interval from RRD Surgery to FCS Appearance (Days)
|Interval from FCS Appearance to MH Diagnosis (Days)
|MFT at FCS Appearance (μm)
|MFT at the Last Visit Before MH Formation (μm)
|MH Size (μm)