Fluorescence diagnosis of endometriosis using 5-aminolevulinic acid

Background: The diagnosis of nonpigmented endometrial lesions by simple laparoscopic visualization is difficult and often inaccurate. We therefore sought to establish a new and more accurate method to visualize these nonpigmented peritoneal changes caused by endometriosis. Methods: A total of 37 patients received 30 mg 5-aminolevulinic acid/kg body weight 10 to 14 hs prior to surgery. Laparoscopy was then performed using a D-Light system (Storz, Tuttlingen, Germany). The findings were evaluated first in the white-light mode; the D-light system was then activated, and all areas of fluorescence were documented. Multiple specimens were obtained by biopsy. Results: The sensitivity of the fluorescence diagnosis in detecting endometriosis in nonpigmented areas and normal-looking peritoneum is 100%, with a specificity of 75%. Diagnosis by simple visualization under white illumination has a sensitivity of only 69% and a specificity of 70%. Occult areas of endometriosis were discovered using fluorescence diagnosis. Conclusions: Our findings suggest that fluorescence diagnosis using 5-aminolevulinic acid is feasible and can improve the diagnosis of endometriosis in nonpigmented and occult endometrial lesions. Fluorescence diagnosis is a promising new tool in the diagnosis of endometriosis.