PURPOSE: Nystagmus is not considered a good indication for laser refractive surgery. However, we report 2 cases with congenital nystagmus that underwent a safe procedure due to improvement of laser firing rate and eye tracker. CASE SUMMARY: Two myopic patients with congenital nystagmus underwent transepithelial photorefractive keratectomy with the Schwind Amaris laser platform using an eye tracker. The laser ablations were performed under topical anesthesia without any mechanical eyeball fixation. A 30-year-old man with a history of muscle surgery at 11 years of age had a conjugate, 4 Hz right beating jerk nystagmus. His preoperative refractive error was -8.50 D sph = -0.50 D cyl x 160degrees x 20/30) in the right eye, and -6.00 D sph = -0.75 D cyl x 30degrees x 20/25) in the left eye. A 19-year-old man had a conjugate, 3 Hz pendular nystagmus. His refractive error was -5.25 D sph = -2.50 cyl x 175degrees x 20/30) in the right eye, and -4.25 D sph = -2.50 D cyl x 180degrees x 20/30) in the left eye. Both patients underwent a well-centered laser ablation without any problems. Six months after surgery, uncorrected visual acuity was 20/25 or better, and refractive error was within +/-0.50 D in all 4 eyes. In addition, the 19-year-old man showed decreased nystagmus amplitude. CONCLUSIONS: In some patients with congenital nystagmus, laser refractive surgery may be safely and accurately performed under topical anesthesia using an active tracking system. The best uncorrected visual acuity may improve in certain patients postoperatively.
Adult ; Anesthesia ; Fires ; Humans ; Laser Therapy ; Nystagmus, Congenital* ; Nystagmus, Pathologic ; Photorefractive Keratectomy ; Refractive Errors ; Refractive Surgical Procedures* ; Visual Acuity ; Young Adult

Periodic alternating nystagmus is a horizontal jerk nystagmus that periodically changes in amplitude and directions every 3 or 4 minutes. Usually the eyes beat in one direction for approximately 90 seconds and then go into a null phase for 10 to 20 seconds before beginning to move in the opposite direction and continued about 90 seconds. The exact mechanism is unknown but the rhythmic alteration of the null zone of horizontal jerk nystagmus is taken as a possible mechanism. These patients periodically show alternating head turning. The authors report 6 cases of congenital periodic alternating nystagmus which show horizontal jerk nystagmus of rhythmic direction change and confirmed by electro-oculogram.
Head ; Humans ; Nystagmus, Pathologic*

We report a case of an otherwise healthy 23-month-old boy who presented with nystagmus, head shaking, and abnormal head posture suggestive of spasmus nutans. Neuro-ophthalmologic exam revealed bilateral, low-amplitude, high-frequency, horizontal, disconjugate nystagmus that was more prominent in one eye along with head shaking and a head tilt or face turn. The rest of the exam and the systemic physical examination were normal. Magnetic resonance imaging of the brain did not disclose optic pathway glioma, which has been reported to cause spasmus nutans-like disease. Electroretinogram (ERG) was also recommended to rule out occult retinopathies. However, it was not done due to unavailability of the appropriate corneal electrode for his age. Instead, close follow-up was advised to monitor spontaneous improvement or resolution, or until the child comes of age that he can undergo ERG. This case highlights the management approach and rationale of patients with presumed spasmus nutans. Recognition of the triad of spasmus nutans allows for quick diagnosis and more focused and efficient investigation.
pathologic nystagmus ; infantile spasms

The possibility that patients with infantile nystagmus achieve spatial constancy by sampling the visual scene only during certain range of velocities or certain phases of their nystagmus cycle was investigated by asking patients to detect a flashed test target that was presented repeatedly during all phases of the nystagmus cycle. After observing a 543 nm fixation spot projected on a diffusely illuminated tangent screen 1 m in front of the eye, patients were asked to detect a 2 msec test flash of the spot, now locked to the retina, that occurred 200 msec after the fixation spot was extinguished. The test target appeared randomly at 3,6,9, or 12 o'clock at, in separate trials, 0.8 deg or 10.0 deg from central vision. To avoid forcing patients from guessing a direction cued by the disappearance of the fixation spot, sometimes the flash did not occur at all. To avoid dark adaptation in our patients, the diffuse background illumination was adjusted to the brightest level allowing easy detection of the test flash. In every condition, all patients reported the fixation spot stationary. The probability of detection was the same across all velocity ranges. Remarkably, patients were just as likely to detect the test flash when the eye was nearly stationary even when it was moving more than 100 deg/sec. In one patient, the background illumination was raised so that he began missing the test flash more often. Here too, the probability of detection, now reduced to about 50%, was the same across velocity ranges. In some patients we tried to backward mask the test flash by having the fixation spot reappear at various time after the test flash (40-2000 msec). Detection probability was unaffected by the reappearance of the fixation spot with the time interval tested. We conclude that the absence of oscillopsia in our patients was not accomplished by a sampling or masking process.
Adolescent ; Adult ; Eye Movements ; Female ; Humans ; Male ; Middle Aged ; Nystagmus, Pathologic/congenital/*physiopathology ; Photic Stimulation ; *Visual Perception

BACKGROUND AND OBJECTIVES: Benign paroxysmal positional vertigo (BPPV) of horizontal canal shows reversible direction changing positional nystagmus and diverse clinical courses because of the frequent clinical presentation of cupulolithiasis. The aim of this study is to find out the early effect of particle repositioning maneuver (PRM) including the barbecue and the modified Semont in single treatment session for the apogeotropic horizontal canal BPPV. SUBJECTS AND METHOD: Thirty-three episodic vertigo patients with direction-changing apogeotropic horizontal nystagmus were enrolled in this study. The patients were initially treated with barbecue rotation and the second PRM was applied 15 minutes after the first PRM. Barbecue rotation was applied when the positional nystagmus was changed its direction to that of geotropic. The modified Semont maneuver or barbecue rotation was randomly applied when nystagmus was not changed. Patients were followed-up 2 or 3 days after the initial visit and the nystagmus was rechecked to determine the single session treatment result. RESULTS: The combination of PRMs in a single treatment session was effective in 23 out of 33 (69.7%) patients. An initial barbecue rotation was effective in 17 patients (51.5%); geotropic nystagmus was obtained in 12, and no nystagmus in 5. Eleven out of 16 (68.8%) patients with persistent apogeotropic nystagmus after initial treatment were successfully treated with the second PRM. There was no statistical difference between the second PRMs of the modified Semont maneuver and barbecue rotation (p=1.000). CONCLUSION: The combination of PRMs including barbecue rotation and the modified Semont maneuver in a single treatment session showed a comparable success rate as the previously reported studies.
Humans ; Nystagmus, Pathologic ; Nystagmus, Physiologic ; Vertigo

No abstract available.
Hemorrhage ; Hypertrophy ; Infarction ; Nystagmus, Pathologic

No abstract available.
Corpus Callosum ; Lithium ; Nystagmus, Pathologic

The authors report a 64-year-old man who developed persistent direction fixed nystagmus after a canalith repositioning maneuver for horizontal canal benign paroxysmal positional vertigo (HC-BPPV). The patient was initially diagnosed with right HC-BPPV given that the Dix-Hallpike test showed geotropic horizontal nystagmus that was more pronounced on the right side, although the roll test did not show any positional nystagmus. The patient was treated with a canalith repositioning maneuver (Lempert maneuver). The next day, the patient experienced a different character of dizziness, and left-beating spontaneous nystagmus regardless of head position was observed. After a forced prolonged left decubitus and frequent head shaking, his symptoms and nystagmus resolved. This condition, referred to as canalith jam, can be a complication after the repositioning maneuver in patients with BPPV. Atypical positional tests suggest that abnormal canal anatomy could be the underlying cause of canalith jam.
Dizziness ; Head ; Humans ; Middle Aged ; Nystagmus, Pathologic ; Nystagmus, Physiologic ; Vertigo

We report a 30-year-old woman with neurocysticercosis, who showed convergence and convergence-retraction nystagmus, V-bobbing, and typical findings of pretectal syndrome due to shunt malfunction. The symptoms and signs improved with shunt revision. The co-development of convergence, convergence-evoked, and convergence-retraction nystagmus, and pretectal pseudobobbing in our patient indicates that these ocular movements may share common pathophysiology of imbalance in the vergence system.
Adult ; Female ; Humans ; Hydrocephalus* ; Neurocysticercosis ; Nystagmus, Pathologic

Internuclear ophthalmoplegia(INO)is a horiwntal ocular motor disturbance caused by a lesion of the medial longitudinal fasciculus. We have experienced a case of bilateral internuclear ophthalmoplegia associated with exotropia, which revealed the symptom of bilateral impairment of adduction and dissociated nystagmus of the abducting eye on horizontal gaze in either direction. No bilateral internuclear ophthalmoplegia caused by trauma has yet been reported in this country. Here we report the case of the trauma-related medial longitudinal fasciculus lesion and its pathophysiology along with a literatural review.
Exotropia ; Nystagmus, Pathologic ; Ocular Motility Disorders*