We have measured the saccadic velocties of nystagmoid and normal ocular movements. The ocular motions of normal subjects and of patients with nystagmus were videotaped using a 3 CCD(color) high resolution camera at 30 frames per second. 8.5-second video segments were selected for analysis. The data was processed digitally using a commercially available image analysis program in a standard 32-bit microcomputer. Measurements were replicated by two analysts. Saccadic velocities of each type of ocular movement were calculated and displayed. Measurement errors between observers and with repeated trials were less than 3%. This new technique is non-invasive, efficient and requires only a camera to obtain video data. It has less noise than conventional methods because of the utilization of video lenses providing very good spatial resolution(1 pixel, 0.33mm), so motion range is much larger than pixel size.
Humans ; Microcomputers ; Noise

Anterior transposition is one of the most commonly used inferior oblique weakening procedures. It has been known to be effective in the case of dissociated vertical deviation with inferior oblique overaction or hypertropia due to superior oblique palsy.this study was undertaken to determine whether anterior transposition is effective in the correction of vertical deviation and head tilt in 19 patients with hypertropia due to superior oblique palsy. Preoperative average scale of inferior oblique overaction was +2.4+/-0.7mm, and the elimination of overaction was noted in 14 patients(74%). Preoperative prism-cover for hypertropia in primary position averaged 12.7+/-6.2, and the mean reduction of hypertropia in primary position was about 10. Head tilt was uniformly eliminated in 9 of 12 patients(75%). Therefore, we can expect the reduction of hypertropia about 10 and the elimination of head tilt, using only anterior transposition in hypertropia and inferior oblique overaction due to superior oblique palsy, especially when the amount of vertical deviation is within 13.
Head ; Humans ; Paralysis* ; Strabismus*

Vertical deviation may sometimes coexit with a large horizontal strabismus. If the vertical component is small and comitant, it may be treated by vertical displacement of the horizontal rectus insertions during a monocular recession-resection procedure. A series of 17 patients had vertical displacement of horizontal rectus muscle insertion monocularly combined with recession-resection surgery. Using a surgical plan of 1mm displacement of both medial and lateral rectus insertion to correct each prism diopter of vertical deviation, 12 patients had no residual vertical strabismus. Minimum follow-up period was 3 months. The linear correlation equation between the amount of corrected vertical strabismic angle and that of vertical displacement of medial and lateral rectus muscle is Y=0.67X+0.22(Y=Prism diopter of correction by vertical displacement, X=millimeter of vertical displacement of medial and lateral rectus muscle). These surgical results showed unsatisfactory effect on vertical deviation of more than 6 prism diopters.
Follow-Up Studies ; Humans ; Strabismus*

Nine patient with paralyzed strabismus of large deviation(Seven patients with lateral rectus or medial rectus muscle palsy and two patients with double elevator palsy) had full tendon transposition procedure. If remained strabismus was large postoperatively, recession of anatagonist of paralyzed muscle and botulinum toxin infection was performed respectively. Five patients achieved single binocular vision within central 10 degree of visual field. And six patients achieved less than 10 prism diopter of deviation in primary position. Our method compares favorably with previously descrived transposition procedure for muscle palsy in terms of the amount of correction and the extent of the window of single binocular vision with low risk of anterior ischemia syndrome.
Botulinum Toxins ; Elevators and Escalators ; Humans ; Ischemia ; Paralysis ; Strabismus* ; Tendons* ; Vision, Binocular ; Visual Fields

Botulinum toxin chemodenervation is widely used for the treatment of acute paralytic strabismus. We reviewed the effect of botulinum toxin chemodenervation for the treatment of chronic paralytic strabismus. Between 1996 and 1998, 13 patients with chronic paralytic strabismus were treated with botulinum toxin chemodenervation. The palsy of extraocular muscle persisted for at least 6 months. Each patient received an injection of 1.25 to 5 units of botulinum toxin[Botox]to the antagonist muscle of the paralytic muscle and two patients received injections two times. The follow-up was more than 6 months [mean 7.62 months].2 patients were treated with surgery of horizontal muscles and 3 patients were treated with muscle transposition surgery before injection. The mean preinjection deviation was 36.7PD and the mean strabismus angle after injection was 19.2PD and improving rate of the strabisbismus angle was 47.6%. The final deviations of 6 patients were within 10PD[46.2%]and 4 of 7 patients with final deviation above 10PD were treated with surgery later. Ptosis occurred in 4 patients[30.8%]and hypertropia occurred in 4 patients[30.8%]. In addition to the prevention of muscle contracture with botulinum toxin injection, it is likely that the therapeutic effect of botulinum toxin is produced by permanent alteration in the muscle and influence on the peripheral and central nervous system. Therefore botulinum toxin chemodenervation can be considered as a primary therapy or a subsequent therapy of surgery for chronic paralytic strabismus and further study is needed.
Botulinum Toxins* ; Central Nervous System ; Contracture ; Follow-Up Studies ; Humans ; Muscles ; Nerve Block* ; Paralysis ; Strabismus*

Malignant melanoma is a rare disease. On the average it occurs in from 0.02 to 0.06 of all eye-patients, that is, from 2 to 6 per 10,000. Malignant melanoma is rare among Negroes; the ratio of Caucasian to non-caucasian patients is 250: 1(Hogan and Zimmerman). The sex incidence shows a slight excess of males. Bilater al cases are exceptional. Hereditary influences are little in evidence. The very early stages of a neoplasm are difficult to come upon, but early growths have been found accidentally in eyes enucleated for other reasons. Extraocular entension may take place at a very early stage in the evolution of a malignant melanoma(when it was 2 X 3mm, Schultz-Zehden, 1905), but occurs most readily from the diffuse type of flat or ring-shaped growth. This does not usually occur directly through the sclera which forms a relatively efficient barrier unless the tumor becomes necrotic and the sclera participates in this process. As a general rule extraocular extension takes the path of least resistance along the channels made by the perforating vessels and nerves. A 42 year old Korean man was seen in our outpatient clinic complaining of a dark rapidly growing mass without pain OD for one month period. He was told that he may have intraocular tumor OD of unknown etiology by some ophthalmologist about 3 years ago. But since then he has never consulted with eyespecialist. Right eyeball including large mass was removed under general anesthesia and reported histopathologically to be malignant melanoma of epithelioid cell type. After surgery he received radiation therapy. Total 4,500 rad x-ray irradiation was applied on the right orbital area for 4 weeks.
Adult ; African Continental Ancestry Group ; Ambulatory Care Facilities ; Anesthesia, General ; Epithelioid Cells ; Humans ; Incidence ; Male ; Melanoma* ; Orbit ; Rare Diseases ; Rupture* ; Sclera

The measurement of eye movements in three dimensions is an important tool to investigate the human oculomotor system. When compared with the conventional electro-nystagmography (ENG) and scleral search coil system (SSCS), the video-oculography (VOG) has a higher accuracy and is a more comfortable and reliable method for the 3D-measurement of human eye movements.
Eye Movements* ; Humans

We reviewed the clinical characteristics and surgical results of patients who had consecutive esotropia after exotropia surgery with at least 6 months of follow-up. The number of transient esotropic cases with more than 10 prism diopter postoperatively was 105[9%] in total 1128 cases and persistent esotropic cases at least for six months after surgery was 24[2%]. Significant correlations were found between the development of consecutive esotropia and the presence of amblyopia[p=0.04], poor stereopsis[p=0.02], suppression of the Worth 4-dot test[p<.01], and recession-resction surgery[p=0.02]. The corrective surgery for consecutive esotropia was performed on 12 cases[1.1%] with unilateral lateral rectus advancement[7 cases], bilateral lateral rectus advancement[3 cases], unilateral medial rectus recession[1 case] and bilateral medial rectus recession[1 case]. All of them showed good results.
Esotropia* ; Exotropia* ; Follow-Up Studies ; Humans

PURPOSE: To evaluate the change of accommodation-convergence parameters after implantation of Artisan phakic intraocular lens (PIOL). METHODS: Prospective study for the patients with the Artisan PIOL implantation was performed. A total of 37 patients (3 males and 34 females) enrolled the study. Preoperatively, convergence amplitude, the stimulus accommodative convergence per unit of accommodation (AC/A) ratio and the near point of convergence (NPC) were evaluated. After the Artisan PIOL implantation, the identical evaluations were repeated at 1 week, 1, 3, and 6 months after the surgery. RESULTS: Mean age was 24.3 +/- 4.8 years old, and preoperative refractive error was -8.92 +/- 4.13 diopters (D). After the implantation, mean refractive errors significantly decreased to within +/-1.00 D, and noticeable complications were not found. The convergence amplitude and the stimulus AC/A ratio increased 1 month after the surgery, but progressively stabilized afterward to near preoperative values. NPC didn't show any significant change over follow-up period up to 6 months. CONCLUSIONS: These results regarding implantation of the Artisan PIOL revealed the increase of accommodation-convergence relationship within first 1 month after the surgery, but progressive stabilization was noted during follow-up periods.
*Accommodation, Ocular ; Adult ; *Convergence, Ocular ; Female ; Follow-Up Studies ; Humans ; Lens Implantation, Intraocular/*methods ; Male ; Myopia/*diagnosis/*surgery ; *Phakic Intraocular Lenses ; Postoperative Period ; Prospective Studies ; Refractive Surgical Procedures/methods ; Treatment Outcome ; Visual Acuity ; Young Adult

This study was prospectively performed to assess the corneal refractive changes after strabismus surgery. Seventy patients who were average 12.56 years old were enrolled and the corneal refractive power was measured with corneal topography system[Videokeratoscope, Eye Sys TM laboratories]. The postoperative corneal refractive changes were not observed at apex, 3 mm zone and 5 mm zone in all the patients, but the corneal refractive power increased at 5 mm zone for one week only in resection and recession surgery group. The corneal refractive changes according to the amount of surgery were not observed, but the significant correlation was noted at apex and 3 mm zone for one week, while at 5 mm zone for 8weeks in horizontal muscle recession surgery group. The corneal refractive changes after strabismus surgery were noted at the peripheral cornea and especially in resection and recession surgery group. Further studies of this subject including more patients of various operation methods are expected.
Cornea ; Corneal Topography* ; Humans ; Prospective Studies ; Refractive Errors* ; Strabismus*