Validation of the "Perrier" parathyroid adenoma location nomenclature

Abstract

Background: In 2009, the "Perrier" nomenclature was introduced to enhance communications among surgeons and specialists regarding the location of parathyroid adenomas. The purpose of this study was to validate the utility of the nomenclature in a prospective manner at a different institution.

Methods: A prospective database was created from June 2010 through January 2011 evaluating 108 consecutive patients. In each case, the location of the parathyroid adenoma according to the nomenclature was predicted individually by an attending physician and a resident based on preoperative imaging studies. A radiologist interpreted the images retrospectively. These predictions were compared to the operative findings.

Results: The mean age of the patients was 61 ± 1 years, and 82% were women. The distribution using the nomenclature was as follows: A (adherent to posterior thyroid capsule) 20%; B (tracheoesophageal groove) 27%; C (tracheoesophageal groove but close to the clavicle) 12%; D (directly over the recurrent laryngeal nerve) 2%; E (easy to identify, inferior thyroid pole) 35%; F (fallen into the thymus) 4%. The overall predicting accuracy was significantly higher for the attending physicians than for the residents or the radiologist (78% vs. 64% vs. 25%, P < 0.001). It was 73-92%, 55-77%, and 12-46%, respectively, for locations with more than four patients. The accuracy was not affected by parathyroid hormone or and calcium levels, or the gland weight.

Conclusions: The "Perrier" nomenclature is reproducible. The most common adenoma locations were B and E in our study, similar to the initial studies. Nevertheless, there is a wide range of preoperative predicting accuracy based on the imaging studies obtained and the interpreter's experience.