Clarifying the mechanism of idiopathic macular hole development in fellow eyes using spectral-domain optical coherence tomography

Comparison of the morphological characteristics of the choroidal sublayer between idiopathic macular holes and epiretinal membranes with automatic analysis

PURPOSE

To compare the choroidal sublayer morphologic features between idiopathic macular hole (IMH) and idiopathic epiretinal membrane (iERM) on spectral-domain optical coherent tomography (SD-OCT) using an automatic segmentation model.

METHODS

Thirty-three patients with idiopathic IMHs and 44 with iERMs who underwent vitrectomies were involved. The enhanced depth imaging mode of SD-OCT was used to obtain the B-scan image after single line scanning of the macular fovea. The choroidal sublayer automatic analysis model divides the choroidal into the choroidal large vessel layer, the middle vessel layer and the small vessel layer (LVCL, MVCL and SVCL, respectively) and calculates the choroidal thickness (overall, LVCL, MVCL and SVCL) and vascular index (overall, LVCL, MVCL and SVCL). The morphological characteristics of the choroidal sublayer in the ERM eyes and the IMH eyes were compared.

RESULTS

The mean choroidal thickness in the macular centre of the IMH eyes was significantly thinner than that of the ERM eyes (206.35 ± 81.72 vs. 273.33 ± 82.31 μm; P < 0.001). The analysis of the choroidal sublayer showed that the MVCL and SVCL macular centres and 0.5-1.5 mm of the nasal and temporal macula were significantly thinner in the IMH eyes than in the ERM eyes (P < 0.05), and there was a difference in the macular centre of the LVCL between the two groups (P < 0.05). In contrast, the choroidal vascular index of the macular centre in the IMH eyes was significantly higher than that in iERM eyes (0.2480 ± 0.0536 vs. 0.2120 ± 0.0616; P < 0.05). There was no significant difference in the CVI of other parts of the macula, the LVCL or MVCL between the two groups.

CONCLUSION

The choroidal thickness of the IMH eyes was significantly thinner than that of the iERM eyes, which was mainly observed in 3 mm of the macular centre and the MVCL and SVCL layers of the choroid. The choroidal vascular index of the IMH eyes was higher than that of the iERM eyes. These findings suggest that the choroid may be involved in the pathogenesis of IMH and iERM.

Traumatic macular hole study: a multicenter comparative study between immediate vitrectomy and six-month observation for spontaneous closure

Background

Closure of traumatic macular hole (TMH) can be achieved spontaneously or by surgical intervention. Thus far, there exist no prospective comparative studies that have analyzed the difference between the two modalities. This study aimed to compare the anatomical and visual recovery of eyes with TMH following either an immediate vitrectomy or six-month observation.

Methods

This was a multicenter prospective comparative study. Eight centers participated in the study. Patient data from 40 eyes with a recent history of blunt ocular trauma and newly formed full-thickness TMH were recruited in this study. The participating patients selected between an early vitrectomy or a six-month observation after a doctor explained the potential benefits and risks of both strategies in an unbiased manner. Twenty-five patients underwent an immediate vitrectomy, and 15 patients received six-month observation. Patients were assessed by spectral-domain optical coherence tomography (SD-OCT) and best-corrected visual acuity (BCVA).

Results

Closure rates were 66.7% for the observational group, and 100% for the surgical group (P=0.002). There were no vision-threatening ocular complications in both groups. For the observational group, the mean closure time was 2.5±1.6 months, and 80% of the hole closure occurred within 3 months; cystic edema on the edge of the hole at baseline was significantly more frequent in the non-closed subgroup than in the closed subgroup (P=0.03). There were no significant differences in the foveal microstructure and in the final visual outcome between the spontaneously closed cases and the surgically closed cases.

Conclusions

TMH had a moderately high incidence of spontaneous closure, but an immediate vitrectomy achieved an even higher closure rate. Vitrectomy was effective and safe to treat TMH, while a 3-month observation for spontaneous closure may be an alternative modality for TMH management. Cystic edema on the edge of the hole may be an unfavorable factor for the spontaneous closure of TMH.

Idiopathic Macular Hole: A Comprehensive Review of Its Pathogenesis and of Advanced Studies on Metamorphopsia

Vitreous anteroposterior traction is an important factor that affects macular hole (MH) formation at the early stage, and vitreous tangential traction can lead to further hole expansion after hole formation. Recent studies have highlighted the significance of Müller cells for the pathogenesis of MH. Since the advent of MH treatment, success rates for MH closure have significantly improved, as has postoperative visual acuity. However, metamorphopsia, an initial and common symptom of MH, still exists. Metamorphopsia is significantly related to the deterioration of visual quality of life and can be used as an independent index to evaluate visual function before and after surgery. In MH patients, metamorphopsia has different manifestations representing different clinical implications. M-CHARTS, as a new means of inspection, can quantify the degrees of metamorphopsia, and with the development of optical coherence tomography (OCT), layer-by-layer scanning of the retinal structure has become possible. These methods enable detailed analysis of the connections between the degree of metamorphopsia and relevant OCT parameters. Preoperative OCT parameters can be used to evaluate the prognosis of the postoperative visual function of MH patients and are therefore of great significance in guiding the treatment of MH patients.

Movement of the inner retina complex during the development of primary full-thickness macular holes: implications for hypotheses of pathogenesis

BACKGROUND

The inner retinal complex is a well-defined layer in spectral-domain OCT scans of the retina. The central edge of this layer at the fovea provides anatomical landmarks that can be observed in serial OCT scans of developing full-thickness macular holes (FTMH). Measurement of the movement of these points may clarify the mechanism of FTMH formation.

METHOD

This is a retrospective study of primary FTMH that had a sequence of two OCT scans showing progression of the hole. Measurements were made of the dimensions of the hole, including measurements using the central edge of the inner retinal complex (CEIRC) as markers. The inner retinal separation (distance between the CEIRC across the centre of the fovea) and the Height-IRS (average height of CEIRC above the retinal pigment epithelium) were measured.

RESULTS

Eighteen cases were identified in 17 patients. The average increase in the base diameter (368 microns) and the average increase in minimum linear dimension (187 microns) were much larger than the average increase in the inner retinal separation (73 microns). The average increase in Height-IRS was 103 microns.

CONCLUSION

The tangential separation of the outer retina to produce the macular hole is much larger than the tangential separation of the inner retinal layers. A model based on the histology of the Muller cells at the fovea is proposed to explain the findings of this study.

Classification of posterior vitreous detachment

Diagnosing a posterior vitreous detachment (PVD) is important for predicting the prognosis and determining the indication for vitreoretinal surgery in many vitreoretinal diseases. This article presents both classifications of a PVD by slit-lamp biomicroscopy and of a shallow PVD by optical coherence tomography (OCT). By biomicroscopy, the vitreous condition is determined based on the presence or absence of a PVD. The PVD then is classified as either a complete posterior vitreous detachment (C-PVD) or a partial posterior vitreous detachment (P-PVD). A C-PVD is further divided into a C-PVD with collapse and a C-PVD without collapse, while a P-PVD is divided into a P-PVD with shrinkage of the posterior hyaloid membrane (P-PVD with shrinkage) and a P-PVD without shrinkage of the posterior hyaloid membrane (P-PVD without shrinkage). A P-PVD without shrinkage has a subtype characterized by vitreous gel attachment through the premacular hole in a posterior hyaloid membrane to the macula (P-PVD without shrinkage [M]). By OCT, a shallow PVD is classified as the absence of a shallow PVD or as a shallow PVD. A shallow PVD is then subclassified as a shallow PVD without shrinkage of the posterior vitreous cortex, a shallow PVD with shrinkage of the posterior vitreous cortex, and a peripheral shallow PVD. A shallow PVD without shrinkage of the posterior vitreous cortex has two subtypes: an age-related shallow PVD and a perifoveal PVD associated with a macular hole.

Vitreo-retinal interface changes on optical coherence tomography in the fellow eyes of patients with macular hole

AIM

To study the vitreo-retinal interface and macular changes on optical coherence tomography (OCT) in the fellow eyes of patients with macular hole.

METHODS

Patients with idiopathic macular hole in one or both eyes presented to our institute between January 2003 and December 2009 were evaluated retrospectively. Demographic details, best-corrected visual acuity and vitreo-retinal interface, and macular changes of the fellow eye on OCT were studied.

RESULTS

Seventy patients underwent OCT of both eyes during the study period. The average age group was 61.96 years and 35 (50%) were females. Among the fellow eyes, normal foveal contour was noted in 36 (51.4%) eyes and 34 (48.6%) eyes were observed to have vitreo-retinal interface changes. Of them, 13 (18.6%) eyes had some stage of full thickness macular hole and 21 (30.0%) eyes had interface changes. There was no statistical correlation between involved eye lesions (P=0.64) or visual acuity (P=0.55) as predictors of development of either fellow eye lesions or poor visual acuity.

CONCLUSION

There is a significant chance of having vitreo-retinal interface findings in the fellow eyes of patients presenting with macular hole. OCT should be considered in both eyes of patients with macular hole to detect early changes in the fellow eyes, which may require an early intervention.