Tilted disc syndrome (TDS): New hypotheses for posterior segment complications and their implications in other retinal diseases

Association between myopia and relative peripheral refraction in children with monocular Tilted disc syndrome

BACKGROUND

This study aimed to investigate the refractive error and relative peripheral refraction in pediatric patients with monocular tilted disc syndrome.

METHODS

This single-center, prospective, cross-sectional, observational study included 49 patients from the Pediatric Ophthalmology Department of the Second Hospital of Hebei Medical University aged 5-17 years with monocular tilted disc syndrome. Eyes with tilted optic discs formed the study group, and contralateral eyes with normal discs served as controls, with mean spherical equivalents of - 3.24 D and - 0.47 D, respectively. Best-corrected visual acuity, spherical equivalent, axial length, tilt ratio, defined as the ratio of maximum to minimum disc diameters, and relative peripheral refraction, assessing myopia-related defocus were compared between groups. Pearson's correlation analysis assessed associations between optic disc tilt and spherical equivalent, axial length, and the total refraction difference value.

RESULTS

Tilted optic discs were associated with significantly greater myopia (- 3.24 ± 1.83 D in tilted eyes and - 0.47 ± 0.72 D in non-tilted eyes, P <.001), longer axial length (24.59 ± 1.04 mm in tilted eyes and 23.45 ± 0.78 mm in non-tilted eyes, P <.001), and a higher tilt ratio (1.43 ± 0.05 in tilted eyes and 1.14 ± 0.04 in non-tilted eyes, P <.001). Discrepancies between tilted and non-tilted eyes were observed in the superior, inferior, and nasal quadrants, and the total refraction difference value (P <.001). In eyes with tilted disc syndrome, a negative correlation was found between the total refraction difference value and the spherical equivalent (P <.001). The tilt ratio of optic disc eyes was significantly greater than that of contralateral eyes and was negatively correlated with the spherical equivalent. There was a positive correlation between the tilt ratio and axial length (P <.001).

CONCLUSIONS

Pediatric patients with monocular tilted disc syndrome exhibited longer axial lengths, more myopic spherical equivalent, and more positive relative peripheral refraction. A greater tilt ratio is associated with larger relative peripheral refraction and axial length, corresponding to more severe myopia.

Morphological characteristics of high myopes complicated by serous retinal detachment with dome-shaped macula or inferior staphyloma

PURPOSE

To investigate the morphological characteristics of dome-shaped macula (DSM) and inferior staphyloma complicated by serous retinal detachment (SRD).

METHODS

Electronic medical records and multimodal images of patients diagnosed with DSM and inferior staphyloma were retrospectively reviewed. Morphological features, including axial length, curvature height, orientation of the dome, presence of retinal pigment epithelial detachment, choroidal vascular features such as subfoveal choroidal thickness, variations in choroidal thickness, presence of abrupt changes in choroidal thickness and presence of large choroidal vessels were analyzed.

RESULTS

Fifty-three eyes of 37 patients were included, of which 33 eyes had DSM and 20 eyes had inferior staphyloma, and 15 (28.3%) were complicated with SRD. Four (12.1%) of the DSM and 11 (55.0%) of the inferior staphyloma eyes had SRD. On univariate analysis of risk factors for SRD, shorter axial length (p = 0.002), presence of inferior staphyloma (p = 0.004), higher subfoveal curve height (p = 0.009), thicker subfoveal choroidal thickness (p = 0.038), greater variation in choroidal thickness (p = 0.005), presence of both abrupt changes in choroidal thickness (p < 0.001) and large choroidal vessels (p = 0.001) showed a significantly higher risk. On multivariate analysis, shorter axial length (p = 0.038) and presence of abrupt changes in choroidal thickness (p = 0.008) were identified as significant risk factors for SRD.

CONCLUSION

SRD was more prevalent in eyes with inferior staphyloma compared to DSM. Shorter axial length and abrupt changes in choroidal thickness were associated risk factors for SRD.

Staphyloma-induced Serous Maculopathy: Natural Course and Treatment Effects

PURPOSE

To study the natural course of staphyloma-induced serous maculopathy (SISM) and the effects of treatments.

DESIGN

Retrospective case series.

PARTICIPANTS

This retrospective analysis included 26 eyes of 20 patients with SISM and at least 12 months of follow-up.

METHODS

Medical records were reviewed for patient demographics, such as age, sex, spherical equivalent, best-corrected visual acuity (BCVA), type of staphyloma, and imaging characteristics. Spectralis OCT B-scans were evaluated for the presence and height of the serous retinal detachment (SRD) at each follow-up visit. An SRD episode was defined as a period with SRD in 1 patient.

MAIN OUTCOME MEASURES

Changes in SRD height and BCVA.

RESULTS

Twenty-six eyes of 20 patients (70% female) were included. The mean age was 54 ± 11 years, and the mean spherical equivalent was -4.8 ± 3.3 diopters at baseline. The staphyloma was located inferior in 12 eyes (46%), inferonasal in 7 eyes (27%), and nasal in 7 eyes (27%). The mean follow-up duration was 73 ± 34 months. During follow-up, the SRD height fluctuated in all eyes, with a mean change of 125 ± 56 μm. The SRD disappeared completely during follow-up in 13 eyes (50%) and then reappeared in 7 eyes (35%). Resolution occurred spontaneous in 8 eyes (31%). The median time of an SRD episode was 25 (interquartile range 14-57) months. Treatment was performed in 20 eyes (77%) and led to resolution of SRD in 3 of the 15 photodynamic therapy treatments (21%), 2 of 5 (40%) anti-VEGF series, and 2 of 4 eyes (50%) treated with topical prednisolone. Best-corrected visual acuity at the final visit (0.42 ± 0.25) was not significantly different from BCVA at baseline (0.34 ± 0.27 logarithm of the minimum angle of resolution, P = 0.07), nor was BCVA change significantly different between treated eyes (n = 19) and nontreated eyes (n = 7, P = 0.3).

CONCLUSION

Serous retinal detachment in patients with SISM fluctuated over time and resolved without treatment in 31% of the eyes. Because treatment does not change the course of BCVA, a wait-and-see policy is advocated in these patients on the exclusion of treatable causes of SRD.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Peripapillary hyperreflective ovoid mass-like structures: multimodal imaging and associated diseases

Growing evidence has demonstrated that peripapillary hyperreflective ovoid mass-like structures (PHOMS) are novel structures rather than a subtype of optic disc drusen. They correspond to the laterally bulging herniation of optic nerve fibers and are believed to be the marker of axoplasmic stasis. PHOMS present in a broad spectrum of diseases, including optic disc drusen, tilted disc syndrome, papilloedema, multiple sclerosis, non-arteritic anterior ischemic optic neuropathy, optic neuritis, Leber hereditary optic neuropathy, and so on. We focus on the multimodal imaging features, pathophysiological mechanisms of PHOMS, and their association with multiple diseases and healthy people in this review to deepen the ophthalmologists' understanding of PHOMS. Additionally, we provide some new directions for future research.

Tilted disc in eyes with fovea plana

PURPOSE

To report the association of tilted disc (TD) with fovea plana.

METHODS

Monocentric retrospective study of consecutive eyes diagnosed with fovea plana, assessed by spectral-domain optical coherence tomography. Analysis of the medical charts and imaging findings of patients to collect demographics, the visual acuity, and the clinical context. The presence of associated conditions was checked by two independent readers in order to classify fovea plana as isolated or part of other conditions.

RESULTS

Twenty-one patients, 9 men and 12 women, aged 12 to 91 years, were included. Fovea plana was isolated and asymptomatic in 10 (47.6%) patients. In 6 (28.5%) patients, fovea plana was associated with ocular albinism and/or nystagmus. In 6 (28.5%) patients, fovea plana was associated with an obliquity of the optic disc typical of TD, isolated (5 cases), or associated with nystagmus (1 case).

CONCLUSION

An association between TD and fovea plana had been reported only once in the literature and had been considered likely coincidental. However, this association could be more common than initially reported and suggests a common pathological process in eye development during embryogenesis.

Deep Optic Nerve Head Morphology in Tilted Disc Syndrome and Its Clinical Implication on Visual Damage

Purpose

To study deep optic nerve head (ONH) morphology in tilted disc syndrome (TDS) and identify factors associated with retinal nerve fiber layer (RNFL) defect.

Methods

In patients with TDS, we evaluated the optic disc shape using the Bruch's membrane opening (BMO)-anterior scleral canal opening (ASCO) offset and measured the border tissue (BT) length, depth, and angle in the direction of the tilt, using radial ONH optical coherence tomography (OCT). We compared the parameters between the TDS groups with and without RNFL defects.

Results

Twenty-one eyes had no glaucomatous RNFL defect, and 38 eyes had a glaucomatous RNFL defect. The group with RNFL defects had a higher baseline IOP, larger tilt axis of BMO-ASCO optic disc margin (76.4° ± 14.5° vs. 87.9° ± 15.4°, P = 0.012), larger BMO-lamina cribrosa insertion (LCI) angle (25.6° ± 9.3° vs. 43.6° ± 15.2°, P < 0.001), and more lamina cribrosa (LC) defects (4.3% vs. 30.6%, P = 0.028) than without RNFL defects. The tilt axis and BMO-LCI angle were significant factors after adjusting for baseline IOP and LC defect. The BMO-LCI angle had excellent diagnostic power for glaucomatous RNFL defect in TDS, similar to the visual field mean deviation.

Conclusions

OCT-based large deep ONH BT angle and tilt axis were factors associated with the presence of RNFL defects in TDS. The results suggest a mechanism of RNFL defect associated with structural ONH deformation. Further investigations are warranted to understand the role of ONH structures in a general population with and without optic disc tilt.

Prevalence of Dome-Shaped Macula and Tilted Disc Syndrome in High Myopia

BACKGROUND AND OBJECTIVE

Dome-shaped macula (DSM) and tilted disc syndrome (TDS) are two macular abnormalities that may occur in eyes with high myopia. The aim of this study was to determine the prevalence of both entities in our population.

PATIENTS AND METHODS

This was a prospective and observational study. Optical coherence tomography of the macula was performed in eyes with high myopia (spherical equivalent [SE] of -8D or greater) to assess the prevalence of DSM and TDS.

RESULTS

Sixty-eight eyes were included. Three eyes (4.41%) had DSM and 8 (11.76%) eyes had TDS. The most common macular anomaly was posterior staphyloma (PS) (12 [17.65%]). From the eyes with DSM (n = 3), only two presented PS. An older age and a higher SE were predisposing factors for PS (P = 0.003).

CONCLUSIONS

A lower prevalence of DSM and a higher prevalence of TDS was observed in our population compared to those reported in literature. [Ophthalmic Surg Lasers Imaging Retina 2023;54:568-572.].

STELLATE MULTIFORM AMELANOTIC CHOROIDOPATHY: Clinical and Multimodal Imaging Features

PURPOSE

To describe the clinical and multimodal imaging features of stellate multiform amelanotic choroidopathy (SMACH; also known as serous maculopathy due to aspecific choroidopathy).

METHODS

Retrospective observational case series of eyes presenting with SMACH. Multimodal imaging including fundus photography, optical coherence tomography (OCT), OCT angiography (OCTA), and indocyanine green angiography (ICGA) was analyzed.

RESULTS

Eighteen eyes from 18 patients (mean age: 28 ± 19 years) were included. The mean follow-up duration was 9 years. Ophthalmoscopy showed a yellowish orange, dendriform choroidal lesion. At presentation, subretinal fluid (SRF) was seen in 10 of 18 cases (56%). Eight patients (44%) showed no evidence of SRF during a mean follow-up of 6 years. Cross-sectional OCT showed hyperreflective fibrous-like changes within the inner choroid with choriocapillaris flow preservation on OCTA. En face OCT showed a hyperreflective choroidal lesion with finger-like projections oriented in a stellate configuration. On ICGA, SMACH showed early and late hypofluorescence. None of the cases showed lesion growth.

CONCLUSION

SMACH seems to be a unilateral choroidopathy characterized by distinctive multimodal imaging features. As SRF was absent in some cases, while a dendriform pattern was a consistent finding in all eyes, the authors propose renaming this entity "stellate multiform amelanotic choroidopathy," a name that retains its previous abbreviation "SMACH."

Myopia: Histology, clinical features, and potential implications for the etiology of axial elongation

Myopic axial elongation is associated with various non-pathological changes. These include a decrease in photoreceptor cell and retinal pigment epithelium (RPE) cell density and retinal layer thickness, mainly in the retro-equatorial to equatorial regions; choroidal and scleral thinning pronounced at the posterior pole and least marked at the ora serrata; and a shift in Bruch's membrane opening (BMO) occurring in moderately myopic eyes and typically in the temporal/inferior direction. The BMO shift leads to an overhang of Bruch's membrane (BM) into the nasal intrapapillary compartment and BM absence in the temporal region (i.e., parapapillary gamma zone), optic disc ovalization due to shortening of the ophthalmoscopically visible horizontal disc diameter, fovea-optic disc distance elongation, reduction in angle kappa, and straightening/stretching of the papillomacular retinal blood vessels and retinal nerve fibers. Highly myopic eyes additionally show an enlargement of all layers of the optic nerve canal, elongation and thinning of the lamina cribrosa, peripapillary scleral flange (i.e., parapapillary delta zone) and peripapillary choroidal border tissue, and development of circular parapapillary beta, gamma, and delta zone. Pathological features of high myopia include development of macular linear RPE defects (lacquer cracks), which widen to round RPE defects (patchy atrophies) with central BM defects, macular neovascularization, myopic macular retinoschisis, and glaucomatous/glaucoma-like and non-glaucomatous optic neuropathy. BM thickness is unrelated to axial length. Including the change in eye shape from a sphere in emmetropia to a prolate (rotational) ellipsoid in myopia, the features may be explained by a primary BM enlargement in the retro-equatorial/equatorial region leading to axial elongation.

Assessment of Ocular Deformation in Pathologic Myopia Using 3-Dimensional Magnetic Resonance Imaging

IMPORTANCE

Ocular deformation in pathologic myopia can affect the entire globe. However, few studies have investigated the equatorial pattern of ocular shape. In addition, the correlation between equatorial and posterior morphology needs to be further explored.

OBJECTIVE

To assess global ocular deformation in pathologic myopia.

DESIGN, SETTING, AND PARTICIPANTS

This hospital-based, cross-sectional study included 180 pathologic myopic eyes with atrophic maculopathy grading C2 (diffuse chorioretinal atrophy) or more from 180 participants who underwent comprehensive ophthalmic examination, including high-resolution 3-dimensional magnetic resonance imaging. In addition, 10 nonpathologic myopic eyes of 10 participants were set as the control group.

Main Outcomes and Measures

According to the cross-sectional view of equator, equatorial shape was classified as round, rectangular, pyriform (noncircular and more protruded in 1 direction), vertical-elliptical, or horizontal-elliptical; according to the nasal and inferior views, the posterior shape was categorized as spheroidal, conical, bulb-shaped, ellipsoidal, multidistorted, and barrel-shaped. Equatorial circularity and ocular sphericity were used to quantitatively assess the morphological variability of the equatorial and posterior regions, respectively. The association between ocular morphology and ocular parameters and myopic maculopathy was also investigated.

Results

The mean (SD) age of 180 participants with pathologic myopia was 55.14 (10.74) years, 127 were female (70.6%), and the mean (SD) axial length of studied eyes was 30.22 (2.25) mm. The predominant equatorial shape was pyriform (66 eyes [36.7%]), followed by round (45 eyes [25.0%]). The predominant posterior shape was bulb-shaped (97 eyes [52.2%]), followed by multidistorted (46 eyes [24.7%]). Equatorial circularity and equatorial shapes were correlated (r = -0.469; 95% CI, -0.584 to -0.346; P < .001) and ocular sphericity was correlated with posterior shapes (r = -0.533; 95% CI, -0.627 to -0.427; P < .001). In eyes with a vertical-elliptical equator, equatorial circularity and ocular sphericity were positively linearly correlated (R2 = 0.246; 95% CI, 0.050-0.496; P = .002) and the prevalence of inferior staphyloma was higher (27.8%; P = .04). Eyes with a horizontal-elliptical equator have the most horizontally oriented axis of corneal flat keratometry (median, 43.55 [interquartile range, 43.84] degrees; P = .01) and tended to present with multidistorted posterior shape (21.7%; P = .04).

Conclusions and Relevance

These findings suggest ocular deformation is common in pathologic myopia and can affect the entire eye, including the equatorial and posterior regions. The morphological classification may enhance the understanding of the diverse patterns of ocular shape in pathologic myopia.

Myopic tilted disc: Mechanism, clinical significance, and public health implication

Myopic tilted disc is a common structural change of myopic eyes. With advancing ocular imaging technology, the associated structural changes of the eye, particularly the optic nerve head, have been extensively studied. These structural changes may increase patients' susceptibility to axonal damage and the risk of developing serious optic neuropathies including glaucoma. They also lead to diagnostic difficulties of disease suspects and treatment dilemmas of patients, which implicate clinical practice and subsequently the health care system. In the context of the mounting prevalence of myopia worldwide and its implications to irreversible visual impairment and blindness, it is essential to gain a thorough understanding of the structural changes of myopia. Myopic tilted disc has been extensively investigated by different study groups. However, generalizing the knowledge could be difficult because of the variable definitions of myopic tilted disc utilized in these studies and the complexities of the changes. The current review aimed to clarify the concepts and discuss various aspects of myopic tilted disc, including the definitions, association with other myopia-related changes, mechanism of tilted disc development, structural and functional changes, and clinical implications.

Anatomic Peculiarities Associated with Axial Elongation of the Myopic Eye

PURPOSE

To describe anatomical peculiarities associated with axial elongation in the human myopic eye.

METHODS

Reviewing the results of previous histomorphometrical investigations of enucleated human globes, as well as reviewing findings obtained in population-based studies and hospital-based clinical investigations of myopic patients and non-myopic individuals.

RESULTS

Myopic axial elongation is associated with a change from a mostly spherical eye shape to a prolate ellipsoid form. It is combined with choroidal and scleral thinning, most pronounced at the posterior pole and less pronounced in the fundus midperiphery. In the fundus midperiphery, the retina and density of the retinal pigment epithelium (RPE) and photoreceptors decrease with a longer axial length, while in the macular region, retinal thickness, RPE cell density, and choriocapillaris thickness are not related to axial length. With axial elongation, a parapapillary gamma zone develops, leading to an enlargement of the optic disc-fovea distance and a decrease in angle kappa. Axial elongation is also correlated with an increase in the surface and volume of Bruch's membrane (BM), while BM thickness remains unchanged. Axial elongation causes moderately myopic eyes to show a shift of BM opening to the foveal direction so that the horizontal disc diameter becomes shorter (with a consequent vertical ovalization of the optic disc shape), a temporal gamma zone develops, and the optic nerve exit takes an oblique course. Features of high myopia are an enlargement of the RPE opening (myopic parapapillary beta zone) and BM opening (secondary macrodisc), elongation and thinning of the lamina cribrosa, peripapillary scleral flange (parapapillary delta zone) and peripapillary choroidal border tissue, secondary BM defects in the macular region, myopic maculoschisis, macular neovascularization, and cobblestones in the fundus periphery.

CONCLUSIONS

These features combined may be explained by a growth in BM in the fundus midperiphery leading to axial elongation.