J Korean Neurol Assoc.  2000 Nov;18(6):794-797.

Premature Reversal Caloric Nystagmus in a Patient withMedulloblastoma, Originated from the 4th Ventricle

• Lee H
• Lee JJ
• Jang SS
• Lee SH
• Lim JG
• Yi SD
• Park YC

Abstract

Some individuals may demonstrate a secondary phase nystagmus (SPN) following the caloric irrigation. It has been stated that if a SPN begins prior to 140 seconds after the onset of caloric stimulation and if the magnitude of the slow phase velocity is greater than 6 degrees/sec, then a premature reversal caloric nystagmus (PRCN) is said to exit. Thus far, there have been no reports describing PRCN in Korea. We described a typical PRCN in a patient with medulloblastoma within the 4th ventricle. The patient had a gaze-evoked horizontal and upbeating nystagmus. However, there was no indication of spontaneous nystagmus. A monothermal caloric test was administered. The initial left beating primary phase nystagmus was subsided at 60 seconds after right cold water stimulation and at 110 seconds, a right beating SPN with 14 degrees/sec of slow phase velocity was appeared and was continuous for 240 seconds. Although the precise mechanism of PRCN is unknown, vestibular nuclei damage may be related.

Keyword

Second phase nystagmus; Caloric stimulation; Premature reversal caloric nystagmus; Medullobalstoma

MeSH Terms

Caloric Tests
Humans
Korea
Medulloblastoma
Nystagmus, Physiologic*
Vestibular Nuclei
Water
Water