Clinical application of photoacoustic imaging for cervical precursor lesion detection

Early diagnosis of a precursor lesion in the uterine cervix is an essential factor in uterine cervical cancer prevention. Although colposcopy is an established procedure for detecting high-risk patients, its accuracy and reproducibility are relatively low. Some supportive or alternative techniques to improve the early diagnosis of a precursor lesion have been studied, and correct diagnosis with high reliability using a minimally invasive, cost-effective technique has been pursued. This study aimed to examine the possibility of using photoacoustic (PA) imaging as a supportive technique to improve the accuracy of early diagnosis of cervical precursor lesions.

A PA imaging system for microvessels was used to detect angiogenesis in severe lesions. A total of 21 patients who underwent surgical treatment and 114 outpatients who visited our colposcopy clinic were examined. A retrospective evaluation of PA images was performed as follows: (i) pathological assessment of the specific PA findings and (ii) retrospective evaluation of the severe lesion detection rate through PA.

PA image evaluation and pathological findings showed dense angiogenesis in a severe precursor lesion appearing as a "hot spot" in the PA image. A comparison with colposcopy findings was performed for accuracy evaluation, and the detection rate of severe lesions using PA was relatively high (positive predictive value, 84.5%; negative predictive value, 82.1%).

Our results indicate the possibility of using PA imaging for early diagnosis of severe cervical precursor lesions. With its ability to yield quantitative information, PA imaging can improve ultrasound diagnosis.