Concomitant Hypertropia with Intermittent Exotropia

PURPOSE: To investigate the incidence and characteristics of vertical deviation in the intermittent exotropia. METHODS: Fifty consecutive intermittent exotropes over age of 5 were prospectively studied. Patients with any significant ocular and neurologic abnormalities or orbital anatomic abnormalities, definite oblique dysfunction with A or V pattern were excluded. Ophthalmologic evaluation included visual acuity, ocular movements, measurements of angle of deviation by prism cover test, Bielschowsky head tilt test, stereoacuity test, and fundus observation for torsion by indirect ophthalmoscopy. RESULTS: We found that 27 children(54%) had concomitant hypertropia in primary position. Mean amount of hypertropia was 4.81 PD(range: 2~20 PD). Thirty nine children(78%) showed positive Bielschowsky head tilt test. No objective torsion was observed. No inferior oblique overaction was found except for only 2 patients. All subjects had good visual acuity and stereopsis. CONCLUSIONS: The incidence of vertical deviation in the intermittent exotropia is much higher than expected. All of the vertical deviations show positive Bielschowsky head tilt test.

The Effect of Bilateral Superior Oblique Tenotomy on Primary Position Horizontal Alignment

To evaluate the effect of superior oblique tenotomy on horizontal deviation at primary position in A-pattern exotropia with bilateral superior oblique overaction.We performed adjustable strabismus surgeries under topical anesthesia in 6 patients with A-pattern exotropia. After adjusting horizontal deviation to orthotropia in primary position by horizontal muscle surgery, we measured angle deviation in up, primary, downgaze position and added bilateral superior oblique tenotomy, and remeasured the angle deviation at same positions. We analyzed the angle deviation at postoperative one day, one month, and three month in comparison with the preoperative value. There were no change of horizontal deviation in primary position in 2 patients, qhile 3 to 8 prism diopter(PD) esotropic shift occurred in 4 patients(average 3.3PD) after bilateral superior oblique tenotomy at last follow-up of 3 month. At 3 month postoperatively, there was a tendency of exotropic shift from esotropia noted at immediate postoperative period. When combined surgeries of superior oblique and horizontal muscle are considered and intraoperative adjustable surgery is not permitted, horizontal muscle surgery can be performed with disregarding the effect of bilateral superior oblique tenotomy on primary position horizontal alignment.

Timing of Amblyopia Therapy in Pure Anisometropic Amblyopia

The aim of this study was to analyze the effect of age at beginning of treatment on the results of anisometropic amblyopia in twenty-two consecutive children. The children who had strabismus or any other ocular disease affecting visual acuity was excluded. Two age groups were defined, according to the age at which treatment was started : 7 years or less(group I. N=10), 8 years or more(group II. N=12). Mean age of group I was 5.3 years old(4.1-7.9), while group II was 10.2 years old(8.0-13.2). Six patients were treated with occlusion therapy, 11 patients with atropine penalization, 1 patient with occlusion therapy and atropine penalization alternatively and 4 patients with spectacle correction only. All children had cycloplegic refraction before treatment and at each visit the corrected visual acuity was assessed. The difference in refractive errors between two eyes before treatment was 2.58D(1-9D) in group I and 2.75D in group II. The mean initial corrected visual acuity of amblyopic eyes was 0.43 in group I and 0.46 in group II. There was no significant difference in initial visual acuity between the two groups. The range of follow up times was from 5 to 60 months, with an average of 18 months. There was no significant difference in final visual outcome of amblyopic eye between the two groups. For patients aged 7 years or less, 80%(8/10) of patients achieved a final visual acuity of 0.8 or better and 90%(9/10) achieved the same final visual acuity as in the sound eye. For patients aged 8 years or more, 83%(11/12) of patients achieved a final visual acuity of 0.8 or better and 83%(10/12) achieved the same final visual acuity as in the sound eye. The initial visual acuity, the methods of therapy did not affect the final visual outcome. In pure anisometropic amblyopia, the patients older than 8 years of age have been treated as effectively as the patients 7 years or less.

A New Computerized Cyclotorsion Test

Cyclotorsion is a well known feature of oblique muscle disorders in the eye, usually associated with vertical and/or horizontal strabismus. Its presence and amount of deviation are not easy to detect, therefore requiring more sensitive and accurate tests. But the present measuring devices such as the double Maddox rod test and Bagolini lens test, known to be the standard tests used for cyclodeviation in these days have some limitations. We developed a new computerized test for the measurement of cyclodeviation that remedies the weak points of the existing tests. The cyclotorsion at any eye position can be measured accurately. It is based on subjective response of the examinee. The examinee wears the red-green glasses and identifies when the two lines on the monitor are parellel while the examiner rotates the red or green line with keystroke of computer keyboard. It is possible to test the deviations in all directions. We hope this computerized application will be accepted widely as an useful subjective torsion test in near future.

A New LogMAR Vision Chart: Jin`s Vision Chart

A new vision chart has been developed. This chart utilizes geometric progression of optotype size instead of arithmetic progression. The optotype is increased or decreased in its size by 1.25X (0.1 log unit) when a line changes. It becomes double or half by change of 3 lines. this principle is based on the suggesstion of International Standard Organization (ISO 8596). There are 3 kinds of vision chart; each one for adult, for children and landolt`s ring chart. They are available in one set. The basic distance for examination is 4 m, but it can be used in 3.25, 5and 6.25m. Five optotypes are arranged in each line, and the corresponding visual acuity is given when more than 3 letters are recognized correctly. The correlation coefficient when compared to ladolt`s ring chart were 0.88 with adult chart and 0.91 with children`s chart.

Amblyopia in Infantile Esotropia

Sixty-eight children who had undergone surgery for infantile esotropia were analysed. The mean follow-up time was 2.7 years. Thirty-two patients without amblyopia prior to surgery remained as such postoperatively except one child(3.1%). There were twenty-seven children that received treatment for amblyopia prior to strabismus surgery. Out of these, twenty children(20/27, 74%) developed recurrent amblyopia in postoperative follow-up period. Dissociated vertical deviation and/or inferior oblique overaction occurred in 21 children(21/39, 54%) in the group free of amblyopia, while those occurred in 16 children(16/29, 55%) in amblyopic group, postoperatively. In conclusion, children without amblyopia before surgery remained as such postoperatively. The development of postoperative vertical deviation such as DVD and IOOA is not related to the existence of amblyopia in postoperative periods.

Effect of Induced Anisometropia on Stereoacuity by Far and Near Distance Random Dot Stereo Test

Induced refractive errors or anisometropia are known to cause reduction in stereoacuity. We compared the reduction of stereoacuities in anisometropia between far and near stereotests to determine the value of these tests as a screening tool of anisometropia. The far stereoacuity of 3m distance was tested with a red-green RDS developed with a color computer, and the near stereoacuity with TNO test in 10 normal adult volunteers. The effect of anisometropia. on the stereoacuity was tested by placing spherical lenses in 0.5 D steps bfore one eye(-2.0 D ~ +2.0 D). Stereoacuities tested at far showed a more rapid decrease than those at near as the power of the lenses was increased. The plus lenses showed more deteriorating effect on the stereoacuity than the minus lenses. And all subjects showed more than 620 arc seconds of stereoacuities with more diopter than +1.5D spherical lens. The far stereotest seems to be a more sensitive screening tool of anisometropia than the near stereotest especially in the mild degree(less than 2.0 D) of anisometropia.

A Study about the Accuracy of Automated Refraction

We analysed the differences between the values of noncycloplegicautomated refraction and manifest refraction by ophthalmologist 150 patients(274 eyes)were studied. We divided these patients into five groups according to the age; Group 1 included patients under 10 yea(n=50 eyes), Group 2 from 10 yrs to 19 yrs(n=74 eyes), Group 3 from 20 yrs to 39 yrs(n=66 eyes), Group 4 from 40 yrs to 49yrs(n=39 eyes), Group 5 over 50 yrs(n=46 eyes); We used Canon Auto Ref R-10 autorefractor and ophthalmologist's refractions were the results of both subjective refraction by retinoscope and objective refraction used by cross cylinder. Between the two examinations, the percentages of eyes of disagreement beyond +/-0.5D were 22%(group 1), 39.2%(group 2), 14.1%(group 3), 15.8%(group 4), 17.4%(group 5) in spherical power; 18%, 23%, 27.3%, 29%, 15.2% in cylindrical power respectively; 20%, 31.9%, 18.2%, 15.8%, 19.6% in spherical equivalent respectively and the percentages of eyes of disagreement beyond +/-10 degrees in cylindrical axis were 25%, 42.6%, 39.2%, 40%, 52.9% respectively. There was no statistic significance between the age groups when we compared the absolute differences of values between two examinations. Conclusively, this study revealed that there were large differences between the values of noncycloplegic automated refraction and manifest refraction by ophthalmologist in the large amout of patients and then our results indicated that automated refraction was dangerous to patient's eyes and subjective refinement was needed by ophthalmologist if patients wanted the spectacle or contact lens.

Joubert Syndrome Presented with Ocular Motor Apraxia

Agenesis of the cerebellar vermis, episodic hyperpnea alternating with apnea, abnormal eye movement, ataxia, and psychomotor retardation are shown in Joubert syndrome. This rare syndrome is inherited as an autosomal recessive trait with variable expression. We report the first cases of Joubert syndrome in Korea, to our knowledge, which showed ocular motor apraxia and agenesis of the cerebellar vermis by Magnetic Resornance Image. From these two cases, we describe the correlation between the cerebellar vermian dysfunction and the ocular motor apraxia.

Pseudoaccomodation in Pseudophakic Eyes with 3M Multifocal Intraocular Lens

We measured the near point of accommodation in 59 patients (59 eyes), who were implanted with 3M diffractive multifocal intraocular lens, in order to evaluote the pseudoaccommodation Average amount of pseudoaccommodation were 3.65 diopter (standard deviation was 1.75) and it was greater than that of monofocal intraocular lens Far vision and age did not affect the pseudoaccommodation. Near visual acuity alone appeared to have a positive correlation with pseudoaccommodation.

Surgical Effect of Type I Nystagmus Blockage Syndrome

Six patients of nystagmus blockage syndrome (type 1) underwent both medial rectus recession and posterior fixation suture. Associated amblyopia wsa treated with occlusion or atropinization before and after surgery. During follow-up period for 12 weeks (4-36 weeks), four patients revealed orthophoria and one was esotropi a less than 5 delta and the other was 4-5 delta exotropia. The tropic status was stable, and in two patients who had manifest latent nystagmus, the amplitude of nystagmus was markedly decreased. Head turn was present in all patients before surgery. After surgery head turn was disappeared in five patients but still remained in one although their tropic status changed to orthophoria and the visual acuities of both eyes were equal.

Intraoperative Adjustment with Topical Anesthetics in Strabismus Surgery

For the better correction of strabismus surgery, various adjustable surgical technics are performed with general or retrobulbar anesthesia. Topical anesthetics with IV analgesics (Fentany 1 citrate) and sedative (Valium) can induce adequate pain control without inhibiting extraocular muscle activities and enable intraoperative adjustment easily and conveniently without the troublesome maneuver of postoperative adjustment and accompanying risk of infection Intraoperative adjustable surgery is better than postoperative adjustable surgery because it is easier to perform due to less tissue edema, enables to avoid the risk of retrobulbar or peribulbar anesthesia, and the risk of infection. We operated 20 strabismic patients aging 10 to 48 years using the intraoperative adjustment and topical anesthetics with the good success rate 90%, within +/- 10 delta after 5 weeks follow-up.

Surgical Effect of Type I Nystagmus Blockage Syndrome

Six patients of nystagmus blockage syndrome (type 1) underwent both medial rectus recession and posterior fixation suture. Associated amblyopia wsa treated with occlusion or atropinization before and after surgery. During follow-up period for 12 weeks (4-36 weeks), four patients revealed orthophoria and one was esotropi a less than 5 delta and the other was 4-5 delta exotropia. The tropic status was stable, and in two patients who had manifest latent nystagmus, the amplitude of nystagmus was markedly decreased. Head turn was present in all patients before surgery. After surgery head turn was disappeared in five patients but still remained in one although their tropic status changed to orthophoria and the visual acuities of both eyes were equal.

Intraoperative Adjustment with Topical Anesthetics in Strabismus Surgery

For the better correction of strabismus surgery, various adjustable surgical technics are performed with general or retrobulbar anesthesia. Topical anesthetics with IV analgesics (Fentany 1 citrate) and sedative (Valium) can induce adequate pain control without inhibiting extraocular muscle activities and enable intraoperative adjustment easily and conveniently without the troublesome maneuver of postoperative adjustment and accompanying risk of infection Intraoperative adjustable surgery is better than postoperative adjustable surgery because it is easier to perform due to less tissue edema, enables to avoid the risk of retrobulbar or peribulbar anesthesia, and the risk of infection. We operated 20 strabismic patients aging 10 to 48 years using the intraoperative adjustment and topical anesthetics with the good success rate 90%, within +/- 10 delta after 5 weeks follow-up.

Surgery for Nystagmus

"Eleven mm recession from insertion of 4 horzontal muscles" was performed for 3 patients with sensory nystagmus and "Classic + 1mm or "Clasic + 40% augmented procedure" were performed for 5 patients with congenital nystagmus who have face turn. The degree of nystagmus was decreased from 20 degrees - 45 degrees to within +/- 5 degrees in 4 of 5 congenital nystagmus patients although degrees of nystagmus were not decreased. No significant diminution or abnomality of the ocular motility was noted after the extensive recession and resection.

Surgery for Nystagmus

"Eleven mm recession from insertion of 4 horzontal muscles" was performed for 3 patients with sensory nystagmus and "Classic + 1mm or "Clasic + 40% augmented procedure" were performed for 5 patients with congenital nystagmus who have face turn. The degree of nystagmus was decreased from 20 degrees - 45 degrees to within +/- 5 degrees in 4 of 5 congenital nystagmus patients although degrees of nystagmus were not decreased. No significant diminution or abnomality of the ocular motility was noted after the extensive recession and resection.

The Effect of 0cclusion in Intermittent Exotropia

Occlusion therapy has been reported to improve the motor phase and sensory phase of exodeviations. We performed occlusion on the preferred eye in intermittent exotropia for three hours a day. Average follow-up time was 15.8 weeks. The frequency of tropic status of exodeviation was decreased in 21 cases(70%). In two cases intermitent pattern was changed to exophoria, and in one case, to exotopia. The size of the deviation angle was changed from 28.93 +/- 7.6 prism diopter(PD) to 24.03 +/- 7.9 PD(p<0.01). In 13 cases(43.3%) the size of the deviation angle decreased more than 6 PD, increased more than 6 PD in one case(3.3%), and in 16 cases(53.3%) the size of deviation angle showed no change. The preference pattern changed from monocular to alternating type in 5 cases. Stereopsis improved in 24% of the cases and did not deteriorate in Others.

Refractive Errors in Strabismic Patients: Fixing Eye Becomes Myopicl

We examined 59 intermittent strabismic patients who were not alternate fixaters. Fixing eyes of these patients were found to be more myopic that the fellow eyes in 80% of the cases, and it was statistically significant(p<0.01). When both eyes were myopic and corrected with glasses, the more myopic of the two eyes was still used to fixate at distant objects(87%). Although neither the duration of strabismus nor the degree of anisometropia was found to be significantly related(r=0.336), we do suspect that myopia of the fixating eyes is causatively related to greaterer use rather than clearer image of certain distant objects without accommodation.

A Case of Ghost Cell Glaucoma in Phakic Eye

A 52-year-old male was visited our clinic complaining of severe right ocular pain, redness. He had highly elevated intraocular pressure, corneal edema, ciliary injection, cells and flare in the anterior chamber, and vitreous opacities. Then We performed anterior chamber paracentesis and aspiration cytology and this showed typical RBC ghosts with Heinz body so we confirmed the diagnosis of ghost cell glaucoma and treated him with standard medical treatment for glaucoma and anterior chamber irrigation. Since there has been no previous reports of cases like this, we present this case for the first time in Korea.

Non-contact tonometry: an ideal method for mass screening

We evaluated one of the new non-contact tonometers, the Pulsair non-contact tonometer, to assess its accuracy and reliability. Measurements on 101 eyes were used to assess its accuracy against Goldmann tonometry measurements, and another 24 eyes were used to assess its reliability (reproducibility). The results showed the instrument to be highly accurate and reliable in measurement.