A Canalith jam recognition model based on changes in nystagmus features: Hydrodynamic consequences of complete and partial obstruction in the posterior Semicircular Canal
Medical Hypotheses, cilt.214, 2026 (SCI-Expanded, Scopus)
- Yayın Türü: Makale / Tam Makale
- Cilt numarası: 214
- Basım Tarihi: 2026
- Doi Numarası: 10.1016/j.mehy.2026.112072
- Dergi Adı: Medical Hypotheses
- Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, BIOSIS, CINAHL, EMBASE
- Anahtar Kelimeler: BPPV, Posterior semicircular canal, Canalith jam, Hydrodynamic obstruction, Atypical nystagmus, Nystagmus reversal, Semicircular canal mechanics
- Sağlık Bilimleri Üniversitesi Adresli: Hayır
Özet
Benign paroxysmal positional vertigo (BPPV) is classically attributed to free-floating otoconia within a semicircular canal (SC), producing transient, short-latency positional nystagmus. However, atypical and refractory presentations—such as altered latency, shortened duration, direction changes without head repositioning, and resistance to repositioning maneuvers—are increasingly reported. We propose a Canalith Jam Recognition Model that distinguishes complete from partial hydrodynamic obstruction of the posterior SC. Using a simplified piston-based framework, we link hydrostatic pressure–dominant condition to complete obstruction and jet-flow with oscillatory reflux to partial obstruction. This model provides a common explanation for previously reported clinical observations and suggests clinically relevant predictions, including the diagnostic value of nystagmus persistence versus fade-out in the head-hanging position and the presence of sit-up reversal nystagmus. The novelty of this work does not lie in the introduction of canalith jam as a diagnosis, but in its reinterpretation as a continuum of hydrodynamic conditions in the canalith jam.