A twin study of cilioretinal arteries, tilted discs and situs inversus

Peripapillary hyper-reflective ovoid mass-like structures (PHOMS): clinical significance, associations, and prognostic implications in ophthalmic conditions

Pioneering advancements in optical coherence tomography (OCT) have facilitated the discernment of peripapillary hyper-reflective ovoid mass-like structures (PHOMS), prevalent neuro-ophthalmological findings associated with an array of ophthalmic conditions, such as optic disc drusen (ODD), papilledema, myopic/tilted optic discs, non-arteritic anterior ischemic optic neuropathy (NA-AION), and optic neuritis. Despite an expanding corpus of research, numerous inquiries persist concerning their clinical significance, correlations with ocular afflictions, and prognostic implications. This comprehensive review endeavors to impart an in-depth comprehension of PHOMS, encompassing facets like conceptualization, detection, pathogenesis, and associations with diverse ophthalmic conditions. Furthermore, we underscore several unresolved quandaries and suggest prospective avenues for future exploration.

Does the Presence of the Cilioretinal Artery Affect the Incidence, Clinical Picture and Progression of Age-Related Macular Degeneration?

The aims of this study were to analyze the relationship between the presence of the cilioretinal artery (CRA) and the incidence, severity and progression of age-related macular degeneration (AMD) and to estimate the influence of the CRA on choroidal and retinal parameters. A total of 287 patients with AMD and 110 healthy controls were enrolled in the study. CRA occurrence was determined using color fundus images. AMD progression was assessed after 3 years. There was no difference in the incidence of CRA between the AMD and control groups (23.34% vs. 24.55%; p = 0.8). Lower-stage AMD was more frequently observed in eyes with the CRA than in eyes without the artery (p = 0.016). The CRA did not influence disease progression (p = 0.79). The CRA did not influence retinal and choroidal thickness and volume parameters or the retinal vessel caliber and functionality in either the AMD or control groups. There was no relationship between CRA presence and CFH Y402H and ARMS2 A69S risk variants. The results did not show a protective effect of the CRA on the incidence and progression of AMD. The CRA may affect the severity of AMD; however, the mechanism of this phenomenon is unclear.

An overview of peripapillary hyperreflective ovoid mass-like structures

PURPOSE OF REVIEW

The purpose of this review is to provide an overview of the ophthalmic findings associated with peripapillary hyperreflective ovoid mass-like structures (PHOMS) in both adult and pediatric patients.

RECENT FINDINGS

PHOMS have recently been identified in a number of different ophthalmic disease entities ranging from nonpathologic to pathologic, including but not limited to anatomic abnormalities (tilting in myopia), optic nerve head drusen, optic disc edema from inflammation (optic neuritis, white dot syndromes), vascular insults (ischemic optic neuropathy, retinal vascular occlusion), and papilledema. The mechanism underlying the formation of PHOMS has not been fully elucidated although it has been hypothesized that PHOMS occur secondary to axoplasmic stasis from crowding at the optic nerve head.

SUMMARY

Although the clinical significance of the presence of PHOMS remains unclear, PHOMS are associated with several disease processes. Understanding the mechanism behind their formation and their impact on optic nerve head structure and visual function may be relevant in patients with optic nerve head pathology. The presence of PHOMS may also correlate with disease severity and duration. Future studies to evaluate whether the formation of PHOMS may be useful as an early indicator of disease or a prognostic tool are warranted.

CILIORETINAL ARTERIES INFLUENCE OPTIC NERVE HEAD, PERIPAPILLARY, AND MACULAR VESSEL DENSITIES IN HEALTHY EYES: An Optical Coherence Tomography Angiography Study

BACKGROUND/PURPOSE

To analyze the influence of a cilioretinal artery (CRA) on macular and peripapillary vessel density in healthy eyes as measured using optical coherence tomography angiography.

METHODS

A total of 83 eyes of 83 patients were included in this study. Optical coherence tomography angiography was performed using the RTVue XR Avanti with AngioVue (Optovue Inc). The macula was imaged with a 3 × 3-mm scan, whereas for the optic nerve head a 4.5 × 4.5-mm scan was taken. Optical coherence tomography angiography images of the optic nerve head were screened for the presence of a CRA.

RESULTS

In 31 eyes, a CRA was detected (37.3%). The vessel density in eyes with a CRA was significantly lower within the optic nerve head (P = 0.005) but higher in the peripapillary capillary network (P < 0.001) and (whole en face) macular superficial capillary plexus (P = 0.025), when compared with eyes with no CRA.

CONCLUSION

Our findings reveal that in eyes with a CRA, the vessel density in the peripapillary and macular superficial capillary plexus is increased, whereas the optic nerve head perfusion (as indicated by vessel density in the inside disk region) is decreased. This has to be considered when analyzing quantitative optical coherence tomography angiography parameters in scientific and clinical applications.

Prevalence of Cilioretinal Arteries: A systematic review and a prospective cross-sectional observational study

PURPOSE

To review studies focusing on cilioretinal arteries (CLRA) in order to assess the overall prevalence and establish the prevalence of CLRA in a Hungarian Caucasian population. METHODS #1: Systematic literature review of published studies with at least 100 participants. METHODS #2: Non-mydriatic digital colour photographs were taken of 1000 consecutively enrolled healthy Caucasian young adult volunteers. Images were graded by two trained independent observers. Number and location of identified cilioretinal arteries were recorded and statistically analysed. RESULTS #1: Prevalence of CLRA ranges from 6.9% to 49.5%. Detection with fluorescein angiography yields the highest values followed by fundus photography and ophthalmoscopy. Unilateral presence of CLRA is between 70.30% and 93.65%, and temporal location is between 80.77% and 100%. RESULTS #2: We found at least one CLRA in 36.5% of the participants and in 22.75% of all the examined eyes. Cilioretinal arteries (CLRA) were unilateral in 75.34% and bilateral in 24.66%. Of all the identified CLRA, 96.16% were originating from the temporal rim of the optic disc. We identified at least one temporal CLRA supplying the macula in 28% of the participants and 16.95% of the examined eyes.

CONCLUSION

Prevalence of CLRA varies depending on identification method. Unilateral presence is unequivocally more frequent similarly to temporal location. From a risk of bias standpoint, high-quality studies are rare. Our data on the distribution pattern of CLRA are similar to that in the international literature. Based on our findings, we assume that slightly more than one-third of the Hungarian Caucasian population has a CLRA.

Short foveo-disc distance in situs inversus of optic disc

Situs inversus of optic disc (SIOD) is thought to be a congenital optic disc abnormality that is caused by dysversion of optic nerve insertion. SIOD, however, has many additional features that cannot be explained by abnormal optic-nerve-insertion directionality. In this study, we measured the distance between the fovea and disc in 22 eyes of 15 SIOD patients. For comparison, two control eyes were matched with each SIOD eye by age and axial length. The vertical distance between the temporal vascular arcades also was measured. The foveo-disc distance was shorter in the SIOD eyes than in the control eyes, while the inter-arcade distance did not differ. Further, we measured the circumpapillary retinal nerve fiber layer thickness, which showed nasal crowding of two humps in the SIOD eyes. This nasal crowding disappeared when we shifted the circle scan by the mean difference (465 μm) of the foveal-disc distance between the two groups. Our findings suggest that the optic disc was located closer to the fovea than it would have been normally. Thus, SIOD might reflect incomplete expansion of the posterior pole in the direction of the fovea-disc axis.

RAP study, report 1: novel subtype of macular neovascularisation type III, cilioretinal MNV3

PURPOSE

To report on patients with macular neovascularisation type III (MNV3) arising from cilioretinal arteries (CRAs) (cilioretinal macular neovascularisation type III (cMNV3)).

METHODS

We reviewed baseline examinations of patients with neovascular age-related macular degeneration using multimodal imaging. We determined the type and distribution of MNV lesions in each cMNV3 case, the range of distances from the fovea, existence of exudative maculopathy, intraretinal haemorrhage and other morphological characteristics. 50 consecutive eyes with usual MNV3 without CRA were included as a control group.

RESULTS

102 eyes of 102 patients were identified with MNV3 lesions. Among these, we found 12 eyes (12%) with cMNV3, 84 eyes (82%) with usual MNV3 without CRA and 6 eyes (6%) with usual MNV3 with CRA. Ten cases of cMNV3 had one lesion, and two cases had two lesions. The lesions were distributed equally between the superior and inferior halves of the macula, whereas in the nasal and temporal halves, there were 8 (57%) and 6 (43%) lesions, respectively. All cMNV3 lesions were located between 500 and 1500 µm from the central fovea except one, which was located between 1500 and 3000 µm. None of the lesions had macular neovascularisation type I (MNV1) or macular neovascularisation type II (MNV2) elsewhere in both groups. Exudative maculopathy and intraretinal haemorrhage were found in seven (88%) and five (63%) of the eight pure cMNV3 cases, respectively.

CONCLUSION

cMNV3 can be solitary or multiple, isolated or accompanied with usual MNV3 lesions, but not with concurrent MNV1 or MNV2. It is frequently associated with extensive exudative maculopathy, intraretinal haemorrhage and subretinal fluid.

Association Between Cilioretinal Arteries and Advanced Age-Related Macular Degeneration: Secondary Analysis of the Comparison of Age-Related Macular Degeneration Treatment Trials (CATT)

Importance

Recent reports suggest that cilioretinal arteries (CRAs) confer protection against developing advanced age-related macular degeneration (AMD).

Objective

To further characterize the association between the presence of a CRA and incidence of geographic atrophy (GA) or choroidal neovascularization (CNV).

Design

This cohort study constituted an ad hoc secondary analysis of data from the Comparison of Age-Related Macular Degeneration Treatments Trials (CATT) and was performed at 44 clinical centers in the United States among participants in CATT with CNV in the study eye and without advanced AMD in the fellow eye at baseline. The presence of a CRA was determined by 2 graders, masked to clinical data, using color fundus photographs, red-free fundus photographs, and fluorescein angiography. The proportion with CRAs at baseline between the study eye with CNV and fellow eye without CNV was first compared. The association of a CRA with incidence of CNV or GA at 5 years among fellow eyes and with incidence of GA among study (treated) eyes was then assessed. In addition, the association of CRAs with the Age-Related Eye Disease Study severity scale among the fellow eyes at baseline was assessed. Data were collected from February 1, 2008, through April 30, 2015, and analyzed from July 1, 2018, through April 30, 2019.

Exposures

Presence of a CRA.

Main Outcomes and Measures

The association between the presence of a CRA and incidence of CNV or GA at 5 years of follow-up.

Results

A total of 350 patients (700 eyes) (230 [65.7% women; mean [SD] age, 77 [7.2] years) were included in the analysis. Cilioretinal arteries were present in 67 of 345 (19.4%) fellow eyes without baseline CNV and 73 of 349 (20.9%) study eyes with baseline CNV (P = .60). Cilioretinal arteries in fellow eyes were not associated with incidence of CNV at 5 years (125 of 278 [45.0%] among eyes without CRAs and 30 of 67 [44.8%] among eyes with CRAs; P = .99) or with incidence of GA at 5 years (110 of 278 [39.6%] among eyes without CRAs and 25 of 67 [37.3%] among eyes with CRAs; P = .89). Cilioretinal arteries in study eyes were not associated with incidence of GA at 5 years (105 of 276 [38.0%] study eyes without CRAs and 26 of 73 [35.6%] study eyes with CRAs; P = .72).

Conclusions and Relevance

The analysis did not find a protective association between CRAs and incidence of CNV or GA among CATT participants who had unilateral exudative AMD. Why these findings were different from those of previous publications is unclear but may be partially explained by the different techniques used to detect CRAs or by the baseline advanced disease in CATT participants.

Trial Registration

ClinicalTrials.gov identifier: NCT00593450.