Transient Rectangular Alopecia after Endovascular Embolization: A Case Series of four Patients Describing Dermoscopic and Histopathologic Findings.

Transient rectangular alopecia after endovascular embolization (TRAEE) is considered a specific form of radiodermatitis that is probably underreported in the literature. We present a case series of four patients from our hospital describing dermoscopic and histopathologic findings. Dermoscopic findings overlap with those of alopecia areata; therefore, TRAAE may be misdiagnosed without a precise history. Histopathology analysis of one of our cases showed different characteristics from the only report in the literature (high proportion of follicles in telogen phase). Initial reports considered that total radiation doses between 3 and 5 Gy produced TRAEE, whereas doses higher than 7Gy could trigger permanent alopecia. However, one of our patients exposed to a total dose of 7.6 Gy had complete hair regrowth.