Seo Young Choi1, Ji-Yeong Jang1, Eun Hye Oh1, Jae-Hwan Choi1, Ji Yun Park1, Seong-Han Lee1, Kwang-Dong Choi2. 1. From the Department of Neurology (S.Y.C., J.-Y.J., K.-D.C.), Pusan National University Hospital, Pusan National University School of Medicine and Biomedical Research Institute, Busan; Department of Neurology (E.H.O., J.-H.C.), Pusan National University School of Medicine, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital; Department of Neurology (J.Y.P.), Ulsan University Medical School, Ulsan University Hospital; and Department of Neurology (S.-H.L.), Chonnam National University Medical School, Chonnam National University Hospital Neurology Department, Seoul, Korea. 2. From the Department of Neurology (S.Y.C., J.-Y.J., K.-D.C.), Pusan National University Hospital, Pusan National University School of Medicine and Biomedical Research Institute, Busan; Department of Neurology (E.H.O., J.-H.C.), Pusan National University School of Medicine, Research Institute for Convergence of Biomedical Science and Technology, Pusan National University Yangsan Hospital; Department of Neurology (J.Y.P.), Ulsan University Medical School, Ulsan University Hospital; and Department of Neurology (S.-H.L.), Chonnam National University Medical School, Chonnam National University Hospital Neurology Department, Seoul, Korea. kdchoi@pusan.ac.kr.
Abstract
OBJECTIVE: To determine the prevalence of central lesions in persistent geotropic positional nystagmus, and characteristics and anatomical substrates of the nystagmus in cerebellar lesions. METHODS: We prospectively recruited 58 patients with persistent geotropic positional nystagmus at the Dizziness Clinic of Pusan National University Hospital. Seven patients with unilateral cerebellar lesions were subjected to analysis of clinical characteristics, oculographic data, and MRI lesions. For comparison, we studied 37 cases of peripheral persistent geotropic positional nystagmus. RESULTS: The prevalence of central lesions in persistent geotropic positional nystagmus was 12% (7/58). Persistent geotropic positional nystagmus in cerebellar lesions was mostly asymmetrical. Horizontal nystagmus changed in direction during the bow-and-lean test with null positions. All patients showed impaired horizontal smooth pursuit bilaterally, and 3 of them also had positional downbeat nystagmus. The peak intensity and asymmetry of persistent geotropic positional nystagmus did not differ between central and peripheral groups (p > 0.05), while there was a difference in the maxima. Lesion overlays revealed that damage to the cerebellar tonsil was responsible for the generation of persistent geotropic positional nystagmus. CONCLUSION: Although persistent geotropic positional nystagmus in cerebellar lesions shares the characteristics of nystagmus measures with peripheral cases, accompanying central oculomotor signs can aid in differentiation. In tonsillar lesions, compensatory rotational feedback due to erroneous estimation of the direction of gravity may generate constant horizontal geotropic positional nystagmus.
OBJECTIVE: To determine the prevalence of central lesions in persistent geotropic positional nystagmus, and characteristics and anatomical substrates of the nystagmus in cerebellar lesions. METHODS: We prospectively recruited 58 patients with persistent geotropic positional nystagmus at the Dizziness Clinic of Pusan National University Hospital. Seven patients with unilateral cerebellar lesions were subjected to analysis of clinical characteristics, oculographic data, and MRI lesions. For comparison, we studied 37 cases of peripheral persistent geotropic positional nystagmus. RESULTS: The prevalence of central lesions in persistent geotropic positional nystagmus was 12% (7/58). Persistent geotropic positional nystagmus in cerebellar lesions was mostly asymmetrical. Horizontal nystagmus changed in direction during the bow-and-lean test with null positions. All patients showed impaired horizontal smooth pursuit bilaterally, and 3 of them also had positional downbeat nystagmus. The peak intensity and asymmetry of persistent geotropic positional nystagmus did not differ between central and peripheral groups (p > 0.05), while there was a difference in the maxima. Lesion overlays revealed that damage to the cerebellar tonsil was responsible for the generation of persistent geotropic positional nystagmus. CONCLUSION: Although persistent geotropic positional nystagmus in cerebellar lesions shares the characteristics of nystagmus measures with peripheral cases, accompanying central oculomotor signs can aid in differentiation. In tonsillar lesions, compensatory rotational feedback due to erroneous estimation of the direction of gravity may generate constant horizontal geotropic positional nystagmus.
Authors: Ji-Soo Kim; David E Newman-Toker; Kevin A Kerber; Klaus Jahn; Pierre Bertholon; John Waterston; Hyung Lee; Alexandre Bisdorff; Michael Strupp Journal: J Vestib Res Date: 2022 Impact factor: 2.354