Two-year evaluation of telepathology.

We evaluated a dynamic telepathology system in routine use after a two-year developmental phase. In two three-month studies, two years apart, all intraoperative frozen sections were examined by one pathologist via the telepathology system. Laboratory technicians sampled tissues at gross examination and were connected with the pathologist by videoconference. Specimens were immediately reviewed after the telepathology diagnosis by the same diagnostician. In the second study there were 342 cases. The mean time required to diagnose small specimens such as biopsies was 8 min (range 4-14); for specimens with extensive gross examination it was 22 min (range 10-45). The telepathology and traditional frozen-section diagnoses agreed in 99.4% of cases, but telepathology took two to four times longer for gross and histological examinations, and up to 10 times longer for histological examination only. There were five false diagnoses (1.5%), two of which originated from telepathology (0.6%) and were recognized in the subsequent light microscopy review. Telepathology is not a replacement for light microscopy, but should be regarded as a complementary technique.