Objective: To evaluate the reliability of 3-dimensional ultrasound (3D-US)
for the measurement of choroidal melanomas.
Design: Retrospective case series.
Participants: Forty-two consecutive cases of choroidal melanoma imaged with
3D-US.
Methods: Tumor measurements obtained with ophthalmoscopy, transillumination
, standard ultrasound techniques, 3D-US, and pathological studies, Tumor di
ameters, heights, and volumes were compared. Our 3D-US tumor measurement te
chniques were tested for intraobserver and interscan reproducibility.
Results: Fifty 3D-US images were studied. The 3D-US tumor measurements were
found to be reproducible (height coefficient of variation [CV] less than o
r equal to3%; diameter CV less than or equal to9.7%; volume CV less than or
equal to 13.2%). There was significant correlation with the usual methods
of tumor measurement (diameter r=0.76; height r greater than or equal to0.9
8). Significant differences were found between measurements at pathological
examination, as compared with both 2-dimensional and 3D-US height measurem
ents (range, 0.73-0.83 mm). This finding was thought to be due to specimen
shrinkage. Three-dimensional ultrasound was found to be at least as reprodu
cible as clinical examination and standard ultrasound techniques used for m
easurement of diameter and height of choroidal melanomas. It was our impres
sion that the 3D-US volume measurements accounted for the geometry of the t
umor better than volume estimates calculated from basal area and tumor heig
ht.
Conclusions: Three-dimensional ultrasound measurements of choroidal melanom
a were reproducible, correlated well with other tumor measurement technique
s, and can be used for measurement of choroidal melanomas.