Atypical Bilateral Posterior Semicircular Canalolithiasis - A Case Series

Area of Science:

• Neurology
• Otolaryngology
• Vestibular Disorders

Background:

• Bilateral posterior semicircular canal benign paroxysmal positional vertigo (PSC-BPPV) is classified under the multicanal subtype by the Barany Society.
• Less common and atypical subtypes of PSC-BPPV, such as short-arm and non-ampullary arm canalolithiasis, have gained attention.
• Identifying bilaterality in these atypical PSC-BPPV subtypes necessitates comprehensive positional testing on both sides.

Purpose of the Study:

• To report three atypical, less-common subtypes of bilateral PSC-BPPV.
• To discuss the clinicodemographic profiles, management strategies, and follow-up of these rare cases.
• To highlight novel presentations of tri-canalolithiasis and bilateral non-ampullary arm canalolithiasis.

Main Methods:

• Case series reporting three patients with atypical bilateral PSC-BPPV.
• Utilized conventional and auxiliary positional tests to diagnose bilaterality.
• Documented clinicodemographic data, repositioning maneuvers, physical therapy, and follow-up outcomes.

Main Results:

• Case 1 presented with bilateral non-ampullary arm PSC-BPPV, a previously rarely reported condition.
• Case 2 and Case 3 exhibited novel tri-canalolithiasis presentations, involving co-occurring ampullary and non-ampullary or short-arm canalolithiasis.
• Successful management was achieved through repositioning maneuvers and physical therapy for all reported cases.

Conclusions:

• The study expands the understanding of rare and atypical presentations of bilateral PSC-BPPV.
• Novel subtypes of tri-canalolithiasis and bilateral non-ampullary arm PSC-BPPV were identified and described.
• Effective management of these complex cases can be achieved with appropriate diagnostic and therapeutic approaches.