Characterising the diagnosis of genetic maculopathies in a real-world private tertiary retinal practice in Australia: protocol for a retrospective clinical audit

Figures & data

Table 1. Common inherited macular dystrophies with similar phenotypic characteristics as atrophic age-related macular degeneration.

Phenotype	Associated genes	Inheritance pattern	Reported phenotypic characteristics
Central areolar choroidal dystrophy	PRPH2	AD	Central geographic atrophy and peripapillary atrophy [23] Speckled FAF pattern, possible reticular pseudodrusen [27]
	CDHR1	AR	Outer retinal/RPE atrophy, Macular chorioretinal Atrophy, or Bull’s-eye maculopathy [28] Yellowish flecks
Late-onset Stargardt disease	ABCA4	AR	Outer retinal/RPE atrophy Yellowish flecks in the retina, irregular and prominent on autofluorescence imaging [29]
Stargardt-like macular dystrophies	ELOVL4 PROM1	AD	Central atrophy May have flecks or specific autofluorescence patterns [29]
Pattern dystrophy	PRPH2	AD	Irregular macular pigmentary changes or atrophy patterns [30] May have flecks or specific autofluorescence patterns
Adult-onset vitelliform macular dystrophies	PRPH2 BEST1 IMPG1 IMPG2	AD	Central vitelliform lesions and marked autofluorescence [15]
Best vitelliform dystrophy	BEST1	AD	Central vitelliform lesions and marked autofluorescence [15] Macular atrophic changes in late stages
Mitochondrial macular dystrophies	m.3243A > G ABCC6	Mitochondrial maternal inheritance	Systemic symptoms, such as hearing loss and diabetes [31]
Late-onset retinal degeneration	C1QTNF5	AD	Well-demarcated macular atrophy Drusen-like yellow deposits [32]
Occult macular dystrophy	RP1L1	AD	Multifocal macular atrophy [23]
North Carolina macular dystrophy	MCDR1 locus on chromosome 6 MCDR3 on chromosome 5 PRDM13	AD	Macula atrophy and drusen-like deposits [33, 34]
X-linked juvenile retinoschisis	RS1	X-linked	Macular atrophic changes in late stages May have peripheral retinoschisis [35]

AD: autosomal dominant; AR: autosomal recessive; RPE: retinal pigmented epithelium.

Figure 1. Study flow.

*Drusen based on the Beckman Initiative for Macular Research Classification Committee standards and defined as extracellular deposits beneath the retinal pigmented epithelium >63 µm) [1].

^†Additional variates at this stage include the impact of ophthalmologist (retinal/general), imaging modality, year of most recent image.

Table 2. Proposed abstraction chart to identify people with macular dystrophy.

ESA ID	ID
Demographics
Age (years)
Age of symptom onset (years)
Sex	Male Female X
Retina ophthalmologist	Yes No
Date of exam (first exam)	Date of first exam	Date (last exam)/NA
Retinal imaging
Eye	Right Left
Refraction
Eye included	Yes No	Yes No
Visual acuity
FAF performed	Yes No	Yes No
FAF atrophy (select one)	Uni-lobular Multi-lobular	Uni-lobular Multi-lobular
FAF lesion (select any)	Speckled Trickling (if yes to either) Nasal location Temporal location	Speckled Trickling (if yes to either) Nasal location Temporal location
FAF-based diagnosis	AMD IRD Unsure	AMD IRD Unsure?
NIR images with OCT scan	Yes No	Yes No
(if yes) grading of atrophic lesions on NIR image	Uni-lobular Multi-lobular (if yes to either) Nasal location Temporal location	Uni-lobular Multi-lobular (if yes to either) Nasal location Temporal location
NIR-based diagnosis	AMD IRD Unsure	AMD IRD Unsure?
CFP performed	Yes No	Yes No
CFP features (select any)	Yellow flecking central Yellow flecking peripheral Pigment central Pigment peripheral	Yellow flecking central Yellow flecking peripheral Pigment central Pigment peripheral
CFP-based diagnosis	AMD IRD Unsure	AMD IRD Unsure?
OCT performed	Yes No	Yes No
OCT (select any)	Reticular pseudodrusen Flecks Lesion under fovea	Reticular pseudodrusen Flecks Lesion under fovea
OCT-based diagnosis	AMD IRD Unsure	AMD IRD Unsure?

CFP: colour fundus photography; FAF: fundus autofluorescence; NIR: near-infrared reflectance; OCT: optical coherence tomography. Participants at this stage have been screened for the presence of atrophy without drusen (according to Figure 1).

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Data availability statement

De-identified data will be available from the principal investigator (H.G.M.) upon reasonable request.