Diagnosis of pili trianguli et canaliculi by frozen section: A rapid and inexpensive method of diagnosis.

We present frozen section as a novel method in the diagnosis of pili trianguli et canaliculi that may serve as a more time- and resource- efficient alternative to current gold- standard electron microscopy. In this case series, three children between ages one and four presented with blonde hair unable to be combed into place. Frozen section was performed and evaluated under light microscopy with easy visualization of the hair shaft abnormality, consistent with the diagnosis of pili trianguli et canaliculi.