ABSTRACT
Lesions at three possible sites can masquerade as apogeotropic horizontal semicircular canal benign paroxysmal positional vertigo (HSC-BPPV), namely: 1) short anterior (ampullary) arm canalolithiasis; and 2) culpulolithiasis, which may be either canal (Cup-C) or utricle-sided (Cup-U). There are no clinical methods or investigations to determine the exact pathological site when a patient with a history compatible with HSC-BPPV is found to have apogeotropic positional nystagmus on the supine roll test. Therefore, the treatment of apogeotropic variant of HSC-BPPV not only poses difficulties but the therapeutic options need to be tailored according to the ostensible localization of the pathology. If the apogeotropic HSC-BPPV is transformed into the geotropic variant, it becomes relatively easier to treat, as the treatment options for the latter are very well established. There are reports of cases of the apogeotropic variant of HSC-BPPV being transformed inadvertently during diagnostic positional tests as well as during therapeutic (intention-to-treat) positional maneuvers. I report here a case of an apogeotropic variant of right HSC-BPPV, that transformed into a geotropic variant during the therapeutic (intention-to-treat) Appiani maneuver, which was subsequently successfully treated with two sequences of Gufoni maneuver after transformation. The patient was followed up at one and 24 hours after the second sequence of Gufoni maneuver with a diagnostic supine roll test, which was negative. The case report is supported by seven videos of the diagnostic and therapeutic positional maneuvers revealing positional nystagmus, its appearance, change, and disappearance as clinical events unfolded during the examination and treatment.
Acknowledgments
To Mr. Renith Kurian, video recorded the diagnostic and therapeutic maneuvers and precisely captured the nystagmus during the entire diagnostic and treatment period and to Mr. Ashraf Hussain for drawing the Figure-1 on CorelDraw graphics suite 2019.
Declaration of interest
The author has no conflict of interest or disclosures to report.
Correction Statement
This article has been republished with minor changes. These changes do not impact the academic content of the article.
Notes
1. 12.3-megapixel rear-facing camera of the Google Pixel android smartphone with quad-core Qualcomm MSM8996 Snapdragon 821 processor coupled with quad-core Qualcomm Kryo CPU and a Qualcomm Adreno 530 GPU, 4GB RAM with 128GB default memory capacity
2. The takeaway Frenzel goggles is a newly designed tool for the bedside examination of nystagmus that consists of a plastic convex lens with a magnifying power of 16 diopters, which removes fixation but lacks infrared digital video cameras mounted in the conventional video-oculography goggles.