Comparisons of choroidal nevus measurements obtained using 10- and 20-MHz ultrasound and spectral domain optical coherence tomography

ABSTRACT Purpose: To compare measurements of lesions clinically diagnosed as choroidal nevi using spectral domain optical coherence tomography (SD-OCT) and 10- and 20-MHz ultrasound (US). Methods: This prospective study, which was conducted between May 2011 and December 2011, evaluated eyes diagnosed with choroidal nevus via photographic documentation using 10- or 20-MHz A- and B-mode US (experienced examiner using both the transpalpebral technique and direct contact) or SD-OCT in the enhanced depth imaging mode (performed by a different examiner blinded to the US results). Anteroposterior (AP) and transverse (T) US sections corresponded to sections adjusted perpendicularly on SD-OCT. Results: We evaluated 14 eyes from 12 patients (six males, mean patient age= 64.5 years) diagnosed with choroidal nevus. The choroidal nevi of all samples had a melanocytic profile. Moreover, eight nevi were located at the equator, five nevi were located in the posterior pole (peripapillary in one sample), and one nevus shifted from the equator to the periphery. On SD-OCT, the maximum measurable dimension was 9 mm. The lesions in the posterior pole were easier to evaluate, and image acquisition of lesions located more peripherally was possible depending on patient cooperation. The accurate assessment of height was difficult. Baseline dimensions on 10- and 20-MHz US were larger than those determined via OCT. No significant differences in height were observed between US and SD-OCT. All parameters were statistically similar between 10- and 20-MHz US measurements. Conclusions: No significant difference in the AP and T diameters was observed between 10- and 20-MHz US measurements; however, these measurements (AP and T) were significantly higher than those obtained using OCT. No significant differences in height were observed among the techniques adopted.

摘要
研究目的：对比采用光谱域光学相干断层扫描（spectral domain optical coherence tomography，SD-OCT）以及10 MHz、20 MHz超声（ultrasound，US）对临床诊断为脉络膜痣的病灶进行测量的结果差异。
研究方法：本前瞻性研究于2011年5月至2011年12月期间开展，纳入经影像学资料确诊为脉络膜痣的患眼，分别采用10 MHz或20 MHz的A型、B型超声（由经验丰富的检查者采用经睑法与直接接触法完成检测），或采用增强深度成像模式下的SD-OCT（由另一名对超声结果设盲的检查者进行操作）进行评估。超声测量的前后径（anteroposterior，AP）与横径（transverse，T）所对应的扫描层面，与SD-OCT上经垂直调整的层面相一致。
研究结果：本研究共纳入12例患者的14只患眼（其中男性6例，患者平均年龄为64.5岁），所有纳入样本的脉络膜痣均为黑素细胞源性病变。其中8颗痣位于眼球赤道部，5颗位于眼球后极部（其中1颗位于视乳头旁），另有1颗痣从赤道部移行至周边部。在SD-OCT下，可测量的最大病灶维度为9 mm。后极部病灶更易于评估，而周边部病灶的图像采集则需依赖患者的配合度。准确测量病灶高度存在一定难度。10 MHz与20 MHz超声测量的基线病灶维度均大于SD-OCT的测量结果。超声与SD-OCT在病灶高度测量上未发现显著差异。10 MHz与20 MHz超声的各项测量参数均无统计学差异。
研究结论：10 MHz与20 MHz超声在前后径与横径的测量上无显著差异，但二者的测量结果均显著高于SD-OCT测量值；不同检测技术在病灶高度测量上均未观察到显著差异。