Optical coherence tomography angiography in choroidal melanoma and nevus

Figures & data

Figure 1 A case with a small choroidal nevus in the posterior pole of the left eye with some small drusen over the lesion.

Notes: (A) The fundus photograph of a pigmented lesion on the macular area without exudative changes. (B) B-scan showing a nearly flat, small choroidal lesion with medium-to-high internal reflectivity. (C) OCTA with slabs crossing the surface of the choroidal nevus at the choriocapillaris level by en face imaging with intact outer retina (arrow). (D) The flow rate over the lesion at the level of choriocapillaris level was evaluated (arrow). It elucidates more concentrated vasculature but is still not much different than nearby retina.
Abbreviation: OCTA, optical coherence tomography angiography.

Figure 2 A case with a small and growing peripapillary choroidal melanoma.

Notes: (A) The fundus photograph demonstrates a pigmented superior peripapillary lesion and pigmentary changes in the macular area due to multiple episodes of increasing subretinal fluid. (B) B-scan shows a small choroidal lesion with medium-to-high internal reflectivity. (C) Cross-sectional B-scan OCTA with slabs crossing the surface of the choroidal melanoma through the choriocapillaris. The RPE–Bruch’s membrane complex shows some derangement with subretinal fluid (arrow) on en face imaging. (D) The flow rate over the lesion at the level of choriocapillaris level was measured, showing thinner vascular area than the nearby choriocapillaris (arrow).
Abbreviations: OCTA, optical coherence tomography angiography; RPE, retinal pigment epithelium.

Table 1 Demographic findings of the patients with small melanocytic nevi and treatment-naive small choroidal melanomas

Characteristics	Choroidal nevus					Choroidal melanoma
	Case 1	Case 2	Case 3	Case 4	Case 5	Case 6	Case 7	Case 8	Case 9	Case 10	Case 11
Age (years)	67	64	55	58	68	49	54	65	55	75	52
Sex	M	F	F	F	M	M	F	M	M	M	F
Eye	OD	OS	OD	OD	OD	OS	OD	OS	OD	OD	OD
Symptom	−	+	+	+	+	+	+	+	+	+	+
Visual acuity	5/10	2/10	3/10	10/10	3/10	5/10	7/10	3/10	3/10	5/10	3/10
Diameter (mm)	2	5	2	7	5	5.3	6.54	8.7	8.5	5	8
Thickness (mm)	Flat	Flat	Flat	2	Flat	1.8	1.5	3	3.6	2	2.23
Subretinal fluid	−	−	−	−	−	+	+	+	+	+	+
Follow-up (months)	24	20	20	21	22	22	24	19	24	20	19

Abbreviations: F, female; M, male.

Table 2 OCTA features of the patients with small melanocytic nevi and treatment-naive small choroidal melanomas

OCTA characteristics	Choroidal nevus					Choroidal melanoma
	Case 1	Case 2	Case 3	Case 4	Case 5	Case 6	Case 7	Case 8	Case 9	Case 10	Case 11
RPE–Bruch’s membrane	Intact	Dotted, thickened	Intact	Thickened	Localized detachment	Disrupted	Disrupted, dome-shaped excrescences	Disrupted, dome-shaped excrescences	Thin and irregular	Double layered, PED	Disrupted, dome-shaped excrescences
Outer retinal layers	Intact	Intact	Intact	Intact	Intact	Obscured IDZ Intact EZ	Deranged and thickened EZ Obscured tumor surface and IDZ	Deranged and thickened EZ Obscured tumor surface and IDZ	Deranged, thickened EZ and IDZ	Thickened EZ and IDZ	Deranged, thickened EZ and IDZ
Flow ratea in affected eye	63.68	66.27	61.46	64.62	67.62	57.96	41.93	53.50	60.82	60.80	47.37 (6×6)
Flow ratea of comparable area in unaffected eye	NA	60.42	60.50	63.05	64.53	62.75	62.37	NA	NA	63.10	61.99
Superficial FAZ (mm^2)	0.23	0.38	0.41	0.26	0.41	0.41	0.02	0.35	0.24	0.43	0.38
Deep FAZ (mm^2)	0.43	1.44	0.49	0.42	0.30	0.49	0.12	0.33	0.69	0.60	0.65
Superficial FAZ (mm^2) of unaffected eye	NA	1.07	0.42	0.31	0.29	0.42	NA	0.48	NA	0.23	0.39
Deep FAZ (mm^2) of unaffected eye	NA	0.52	0.54	0.52	0.25	0.54	NA	0.74	NA	0.49	0.48

Note:

a Flow rate (%) = (Flow area/selected area) ×100 on 31–59 µm section below the level of RPE by 3×3 mm scan.

Abbreviations: EZ, ellipsoid zone; FAZ, foveal avascular zone; IDZ, interdigitation zone; NA, not applicable; OCTA, optical coherence tomography angiography; PED, detached RPE; RPE, retinal pigment epithelium.

Table 3 OCTA FAZ and flow rate in the affected eye with melanoma or nevus versus the fellow eye in 11 consecutive cases

OCTA characteristics	Nevus (n=5)	Melanoma (n=6)	P-valuea
Affected eye
Superficial FAZ (mm^2), medianb (range)	0.38 (0.23–0.41)	0.37 (0.02–0.43)	0.926
Deep FAZ (mm^2), median (range)	0.43 (0.30–1.44)	0.55 (0.12–0.69)	0.784
Flow rate % (31–59 µm), median (range)	63.68 (60.42–67.62)	55.73 (41.93–60.82)	0.006
Non–affected eye
Superficial FAZ (mm^2), medianb (range)	0.37 (0.29–1.07)	0.39 (023–0.42)	0.685
Deep FAZ (mm^2), medianb (range)	0.52 (0.25–0.54)	0.49 (0.48–0.54)	0.661
Flow rate % (31–59 µm), median (range)	61.77 (60.42–64.53)	62.75 (61.99–63.10)	0.773
P-value (affected vs nonaffected contralateral eye)	0.09	0.01

Notes:

a Mann–Whitney U test.

b Median is presented for small sample size.

Abbreviations: FAZ, foveal avascular zone; OCTA, optical coherence tomography angiography.