INITIAL CONFIRMATION OF A SITUS INVERSUS TOTALIS BY INTRAOPERATIVE NEURAL MONITORING IN A PATIENT UNDERGOING PARATHYROID SURGERY

AUTHORS:
J.N. Marx (Halle (Saale), Germany) , S. Ilker (Halle (Saale), Germany) , M. Elwerr (Halle (Saale), Germany) , K. Lorenz (Halle (Saale), Germany) , R. Schneider (Halle (Saale), Germany)
Background:
The significance of neural risk minimization in endocrine neck surgery using intraoperative monitoring (ION) increased the past 20 years. Normal quantitative ION parameters for vagus (VN) and recurrent laryngeal nerves (RLN) were established, a prerequisite to interpret intraoperative ION changes in order to preclude neural injury during dissection. In regular anatomy, a significantly longer latency of the left VN is observed. Situs inversus is a rare condition with completely reversed anatomy of the thoracic and visceral organs, associated with delayed diagnosis and challenges in the event of surgery.
Methods:
Case report of a 59-year-old patient operated for primary hyperparathyroidism with preoperatively by patient history suspected but not confirmed situs inversus totalis.
Results:
ION of the patient`s right VN revealed typical latency consistent with normal median values of a left NV, thereby revealing the suspected situs inversus totalis that was later confirmed in imaging.
Conclusions:
In case of reversed latency values of the VN, on the right side consistent with the normal values of a left VN, a situs inversus must be suspected. However, special attention should be paid when ION reveals a very short latency consistent with a non-recurrent laryngeal nerve in this scenario when an aberrant left subclavian artery may prevail.