Retrograde cricopharyngeal dysfunction: Two case reports and a literature review.

Retrograde cricopharyngeal dysfunction (RCPD) is a fairly recently described condition that has been gaining traction online. Majority of patients arrive at the diagnosis themselves, after undergoing numerous inconclusive investigations, indicating that widespread dissemination within the medical community remains to be seen. We present two cases, the first describes the successful medical management of a 17-year-old male who was treated with rikkunshito, a Kampo medicine, combined with mosapride, an established prokinetic agent. The second case involves a 30-year-old female with refractory symptoms who was effectively managed with endoscopic cricopharyngeal myotomy. She had previously undergone percutaneous botulinum toxin injection that initially provided temporary relief. Both patients experienced a lifelong inability to belch, and had previous unrevealing diagnostic evaluations. Prior to treatment, high-resolution manometry was performed on both patients, showing elevated basal upper esophageal sphincter (UES) pressure and absence of UES relaxation with attempted belching. These findings finally led to a diagnosis of RCPD. Increased clinician awareness of RCPD could potentially spare patients from a meandering clinical course. Alternative medicine, such as rikkunshito, could be a potential adjunct for patients unwilling to undergo procedures. For refractory cases and those intolerant of repeated injections, more extensive surgery, including cricopharyngeal myotomy, may be offered.