Classification of hydatid liver cysts.

A number of investigations advocate various classification systems for liver hydatid cysts. However, none permits predicting the treatment outcome or making clinical decisions regarding medical treatment; open surgery; punction, aspiration, injection, reaspiration (PAIR); or laparoscopy. An international hydatid disease registry employing an uniform nomenclature and consistent reporting methods would allow more rational comparison of different management strategies. TN(R)C (topography, nature, recurrent, complication) classification is a comprehensive system based on four criteria: location (T), natural history (N), recurrence (R) and complications (C) of the cyst. This pictorial review illustrates the classification and puts accent of its clinical usefulness. The TN(R)C classification provides a standardized description formula of every liver hydatid cyst, permitting multiple comparisons and analyses.