Comparison of the objective ocular torsion measured with GMPE module-based OCT and fundus color photography / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To compare the consistency and feasibility of objective ocular torsion measured with GMPE module-based optical coherence tomography(OCT)and fundus color photography(FCP).METHODS: Patients were enrolled in our strabismus clinic from December 2020 to March 2021, and the objective ocular torsion of the eyes was measured by both GMPE module-based OCT and FCP on the same day. FCP was used to measure the fovea-disc angle(FDA)manually by using the Adobe Photoshop software, while the GMPE module-based OCT software positioned automatically the macula and the center of the optic disc to measure the FDA.RESULTS: Fifty-five patients were included, the FDA measured by OCT was -6.6°±4.5° in the right eye and -8.8°±4.7° in the left eye, respectively; The FDA measured by FCP was -6.6°±4.7° in the right eye and -8.4°±4.1° in the left eye, respectively, with no statistically significant difference between the results of the two methods(Pright eye=0.90, Pleft eye=0.08). In patients with exotropia, the FDA measured by OCT was -5.8°±4.9° in the right eye and -9.1°±4.5° in the left eye, respectively, the FDA measured by FCP was -5.7°±5.0° in the right eye and -8.6°±4.3° in the left eye, respectively,(Pright eye=0.75, Pleft eye=0.15). Similarly, the patients with esotropia, the FDA measured by OCT was -9.0°±7.3° in the right eye and -11.3°±3.5° in the left eye, respectively, while the FDA measured by FCP was -10.0°±7.0° in the right and -10.1°±2.8° in the left eye(Pright eye=0.21, Pleft eye=0.10), respectively. There were no significant differences between the two methods in patients with esotropia or exotropia(P>0.05). The results of both Pearson test and Bland-Altman analysis were highly correlated(rright eye=0.93, rleft eye=0.94, P<0.01). CONCLUSION: GMPE module-based OCT can be used for objective ocular torsion measurement with high reliability and reproducibility, and is a promising clinical alternative to the fundus color photographic method.

Comparison of torsional amplitudes between emmetropes and myopes using after-image slides

Purpose: To describe the influence of corrected refractive error on measured torsional fusional amplitudes (TA) by comparing the TA between emmetropes and spectacle corrected myopes, using the after-image slides of the synoptophore, as targets. Methods: Fifty emmetropes (Group I) and 50 myopes (Group II) with best-corrected acuity of 6/6 in each eye were included in the study. Near point of convergence (NPC), near point of accommodation (NPA), and horizontal fusional amplitudes (HFA) were assessed in all the subjects. After-image slides, both horizontally aligned, were used as targets (without the bright flashes). One of the slides was rotated inwards, till cyclo-diplopia was reported by the subject; the procedure was repeated with the slide rotated outwards. The sum of the two readings was taken as TA. NPC, NPA, HFA, and TA were analyzed. Results: There was no significant difference in the NPC, NPA, and HFA between the two groups. The emmetropic subjects had significantly better torsional amplitude (8.4 ± 1.4 degrees) compared to myopes (7.7 ± 1.5 degrees, P = 0.03). We postulate that this difference may be due to perceived image minification, which brings the edges of retinal image of the targets closer to the fovea, thus rendering the myopes lesser tolerant to cyclodiplopia than emmetropes. Conclusion: Refractive error, corrected with spectacles, influences the measured TA. Myopic subjects have lesser torsional fusional amplitude than emmetropes.

Diagnostic Availability of Blind Spot Mapping for Ocular Torsion

PURPOSE: To evaluate diagnostic the usefulness of blind spot mapping in measuring ocular torsion changes and to investigate the correlations of inferior oblique muscle overaction (IOOA) and excyclotorsion measurements using fundus photographs and blind spot mapping in patients with secondary IOOA. METHODS: Eleven patients (12 eyes; IOOA group) diagnosed with secondary IOOA were evaluated for ocular movement, fundus photograph and Humphrey standard automated perimetry, and 10 patients (20 eyes; control group) were subjected to the same tests. An ocular movement examination was performed to evaluate IOOA, and fundus photograph and Humphrey standard automated perimetry were used to measure the ocular torsion. Inferior oblique myectomy or recession was performed along with horizontal strabismus surgery, and preoperative and postoperative IOOA and ocular torsion measurements were compared between the groups. RESULTS: In the IOOA group after surgery, the IOOA decreased from +2.42 ± 0.63 to +0.50 ± 0.52, the ocular torsion decreased from +14.15 ± 3.60° to +7.47 ± 1.65° (p < 0.001) on fundus photographs, and from +12.19 ± 1.62° to +9.69 ± 1.75° (p = 0.061) in Humphrey standard automated perimetry. The control group showed a mean ocular torsion of 7.44 ± 1.62° on fundus photographs and +7.24 ± 1.28° on Humphrey standard automated perimetry. CONCLUSIONS: The usefulness of blind spot mapping when the ocular torsion was measured in IOOA patients was considered low, due to the weak correlation between IOOA and extorsion; preoperative and postoperative ocular torsion amount values were not significantly different.

Isolated Infarction of Anterior Cerebellar Vermis / 대한평형의학회지

The anterior cerebellar vermis has been known to act in coordination of gait and postural adjustment of the trunk and legs. However, oculomotor abnormalities in an isolated anterior vermian lesion have not been described in the literature. A 59-year-old man presented with acute non-rotatory dizziness and disequilibrium. Neuro-ophthalmologic examination found impaired smooth pursuit and hypometric saccades in the contralesional direction, and disconjugate ipsiversive ocular torsion, but without spontaneous or gaze-evoked nystagmus. Imaging study showed an infarction restricted to the rostral end of right cerebellar vermis involving the lingual and central lobules. The anterior cerebellar vermis participates in the maintenance of axial posture and gait, and also in the control of ocular motor and vestibular systems.

Comparison of Diplopia and Ocular Torsion Rate in Blow-Out Fracture Patients

PURPOSE: We compared ocular torsion rates in blow-out fracture patients before and after blowout fracture repair by analyzing mean disc foveal angles. METHODS: The study participants were divided into 2 groups: blow-out fracutre repair patients (n = 36) and controls (n = 36). We measured ocular torsion rates by analyzing mean disc foveal angle. The angle was composed of 2 imaginary horizontal lines which crossed the optic disc center and fovea. We compared statistically ocular torsion rates in blow-out fracture patients based on subsided diplopia, continued diplopia, or absence of diplopia before and after blow-out fracture repair using paired t-test. RESULTS: In the patient group, ocular torsion rates were statistically significantly decreased. In the blow-out fracture repair group with subsided diplopia, ocular torsion rates were decreased statistically from 7.74 +/- 3.48 degrees before blow-out fracture repair to 5.02 +/- 3.11 degrees after blow-out fracture repair. In the blow-out fracture repair group with continued diplopia or absence of diplopia before surgery, ocular torsion rates did not change statistically significantly from 6.36 +/- 2.80 degrees before blow-out fracture repair to 6.51 +/- 3.24 degrees after blow-out fracture repair. CONCLUSIONS: Subsided diplopia after blow-out fracture repair and ocular torsion rate changes were significantly related in blow-out fracture patients. Further research which on the correlation of intraorbital change and movement of orbital position after blow-out fracture repair with ocular torsion rates are necessary.

Ocular Torsion Measured by Fundus Photographs and Optical Coherent Tomography in Normal Koreans

PURPOSE: To investigate the normal range of ocular torsion in Koreans with no ophthalmologic history using fundus photographs and optical coherence tomography and compare the results of the two methods. METHODS: Fundus photographs and optical coherence tomography were conducted in 400 eyes of 200 people with no ophthalmologic history. ImageJ(R) was used to measure the center of the optic nerve head to foveal angle with fundus photographs. For optical coherence tomography, the fovea-to-disc alignment function in the computer program was used to automatically calculate the angle. Then, the calculated angles measured by the two different methods were compared. RESULTS: In fundus photographs, the angle of the fovea from the center of the optic nerve head was 6.26 +/- 2.92 degree in the right eye, 6.65 +/- 2.58 degree in the left eye, and the mean value was 6.47 +/- 2.76 degrees. From the automatic calculation in optical coherence tomography, the angle of the fovea from the center of the optic nerve head was 6.12 +/- 3.00 degree in the right eye, 6.83 +/- 2.70 degree in the left eye, and the mean value was 6.52 +/- 2.83 degrees. There was no statistically significant difference between the results of the two different methods. In addition, no statistically significant difference was observed between the right and left eyes, sexes, or ages. CONCLUSIONS: When comparing the conventional method of measuring ocular torsion with fundus photographs to optical coherent tomography, the fovea-to-disc alignment function of the optical coherent tomography may be useful to automatically calculate the cyclotorsion.

Age and Gender Specific Reference Value of Ocular Torsion by Using Funduscope in Korean / 대한평형의학회지

BACKGROUND AND OBJECTIVES: Ocular torsion may be a result of vestibulopathy. The funduscopy is the most reliable method of measuring an ocular torsion. However, the reference value of ocular torsion in Korean is available at only limited ages. Therefore, we analyzed the angle of ocular torsion more age-specific than previous study. MATERIALS AND METHODS: We used the fundus photograph of health check-up visitor. And age and sex specific average angle of ocular torsion was measured. RESULTS: The right and left average angle of ocular torsion were 7.7+/-3.6degrees, 5.3+/-3.0degrees, respectively. In addition, there was no significant difference in age or sex specific angle of ocular torsion. CONCLUSION: This result might give an aid to evaluating the function of otolithic organ by measurement of ocular torsion.

Measuring normal ocular torsion and its variation by fundus photography in children between 5-15 years of age.

Cycloposition has been measured by various methods; however, fundus photography is the most reliable method to evaluate the torsion objectively. We did a prospective study to find out the disc foveal angle (DFA) and its variation in children without squint. We included 210 eyes of 105 children between the ages of 5-15 years. DFA was calculated using standard technique after taking a fundus photograph. The cycloplegic refraction was done and compared. The mean age was 10.6 ± 2.5 years. Mean DFA in right eye (RE) was 6.49 ± 3.25° (0-13°) and in left eye (LE) was 5.80 ± 3.29° (0-12°). The difference between the RE and LE was statistically not significant (P=0.131) (mean 1.15 ±1.39°). Mean DFA in emmetropic children was 6.1° ± 3.4° (n=112 eyes). DFA varies widely in children. The difference observed in DFA measurement for eyes with various refractive errors were compared with DFA measurements for emmetropic eyes.

Ocular Torsion in Unilateral Superior Oblique Palsy

PURPOSE: We evaluated the concordance of laterality of the paretic eye and the torsional eye in unilateral superior oblique palsy showing an inferior oblique overaction. METHODS: Thirty-nine patients diagnosed as having a unilateral superior oblique palsy were evaluated for visual acuity, refractive manifestation, ocular movement, prism cover test, and fundus photograph. Of these patients, 32 derived from congenital causes and 7 acquired the condition from trauma. An ocular movement exam was performed to check an inferior oblique overaction, and a fundus photograph was used to measure the ocular torsional amount. Inferior oblique myectomy or recession was performed along with horizontal strabismus surgery. RESULTS: Objective extorsion was presented in paretic eyes of 29 patients (74.4%) and nonparetic eyes of 10 patients (25.6%). The congenital superior oblique palsy patients were divided into two groups by the concordance of laterality of paretic eyes and torsional eyes. In the concordance group of 22 patients, the torsional amount was decreased from +17.69 degrees to +7.98 degrees and inferior oblique overaction from +2.27 degrees to +0.25 degrees after an inferior oblique muscle weakening procedure. In the discordance group of 10 patients, torsional amount was decreased from +16.97 degrees to +8.73 degrees and inferior oblique overaction from +2.50 degrees to +0.21 degrees postoperatively. In acquired oblique palsy patients, all patients showed the concordance of laterality, and the torsional amount was decreased from +16.76 degrees to +8.80 degrees and inferior oblique overaction from +2.5 degrees to +0.21 degrees after inferior oblique weakening procedure. CONCLUSIONS: We found that the paretic eye and the torsional eye may not coincide in congenital superior oblique palsy but always coincide in acquired oblique palsy after trauma. After an inferior oblique muscle weakening procedure, ocular torsional amount of paretic or sound eye is decreased in every case.

Ocular Torsion according to Fixation in Fundus Photograph

PURPOSE: We examined the torsional change of eyeballs according to fixation using fundus photography. METHODS: We took fundus photographs of both eyes of the following patients: group 1, 10 unilateral superior oblique (SO) palsy patients; group 2, 20 exotropia (XT) patients without vertical strabismus or oblique dysfunction; and group 3, 20 normal subjects, from March 2002 to February 2005, using a fundus camera with and without fixation on the internal fixation device. We examined the torsional angle (alpha) between the horizontal line through the optic disc center and the line connecting to optic disc center with fovea using the Scion Image Program, and compared the torsional change according to fixation. RESULTS: The torsional angle (alpha) was 17.92 degrees with fixation and 18.79 degrees without fixation in paretic eyes of group 1 (p=0.46), and 8.78 degrees with fixation and 9.23 degrees without fixation in sound eyes of group 1 (p=0.36). The torsional angle was 6.35 degrees with fixation and 6.86 degrees without fixation in the right eyes of group 2 (p=0.39), and 6.40 degrees with fixation and 6.95 degrees without fixation in the left eyes of group 2 (p=0.28). In group 3, torsional angle was 6.95 degrees with fixation and 7.25 degrees without fixation in the right eyes (p=0.72), and 7.42 degrees with fixation and 7.48 degrees without fixation in the left eyes (p=0.89). Torsional angle with fixation was smaller than without fixation in all groups, but the differences were not statistically significant. CONCLUSIONS: There was no torsional change according to fixation by fundus photography in unilateral SO palsy patients, XT patients without vertical strabismus or oblique dysfunction, and normal subjects.

Ocular Torsion in Normal Korean Population

PURPOSE: We determine the normal variation in cyclotorsion, the difference between the two eyes of each individual, and the torsional changes according to age and sex. METHODS: We examined the horizontal and vertical distances from the center of the disc to the fovea and the angle with fundus photographs of 100 ophthalmologically normal subjects (200 eyes). We calculated the vertical/horizontal disc ratio and the difference of the vertical disc-foveal distance and angle between the two eyes of each individual. We studied the changes of all the measured parameters according to age and sex. RESULTS: The horizontal distance from the center of the disc to the fovea was 2.62 +/- 0.25 DD in the right eye, 2.60 +/- 0.25 DD in the left eye, and the mean was 2.61 +/- 0.25 DD. The vertical distance from the center of the disc to the fovea was 0.28 +/- 0.15 DD in the right eye, 0.30 +/- 0.15 DD in the left, and the mean was 0.29 +/- 0.15 DD. The angle was 6.11 +/- 3.21degrees in the right eye, 6.67 +/- 3.18degrees in the left, and the mean was 6.39 +/- 3.20degrees. The difference of the vertical distance and the angle between the eyes was 0.13 +/- 0.09 DD and 2.98 +/- 2.07, respectively. The parameter change according to age and sex was not statistically significant (p>0.05). CONCLUSIONS: If the fovea was from 0.01 DD above center of the disc to 0.09 DD below the lower edge of the disc, we could confirm the absence of cyclotropia. There was no significant change of any of the measured parameters according to age and sex in the normal population.

Ocular Tilt Reaction

PURPOSE: To report the clinical manifestations of patients with ocular tilt reaction (OTR) and the differential point from other disorders with abnormal head posture. METHODS: The clinical manifestations of four patients who complained of abnormal head posture and diplopia and who were diagnosed to have OTR from January, 2001 to January, 2002 were investigated. The diagnoses were made with alternate cover test, duction and version test, Lancaster test, Bielschowsky head tilt test, fundus photography, and brain MRI. RESULTS: All the four patients showed ipsilateral head tilt, ocular torsion, and vertical deviation. Type of their OTR was tonic OTR. Subjective tilting of visual vertical was observed in one patient. Only with the 3-step test, OTR could be misdiagnosed as an extraocular muscle palsy. The most important sign in differentiation from other disorders of abnormal head posture was ocular torsion. Duction and version examination and tilt of subjective visual vertical were also helpful for the differentiation. CONCLUSIONS: OTR should be considered in patients with ocular torsion, vertical deviation and ipsilateral head tilt. In patients with diplopia and head tilt, examination of ocular torsion should be performed with the 3-step test in order not to make a misdiagnosis of extraocular muscle palsy.

Ocular Torsion and Tilt of Subjective Visual Vertical and Head in Patients with Acute Brainstem Stroke

BACKGROUND & PURPOSE: The ocular torsion (OT) and tilt of the subjective visual vertical (SVV) are sensitive brainstem signs and helps us to localize lesion. We calibrated the degree of OT, SVV tilt and head tilt to investigate their characteristics and temporal profiles in patients with brainstem lesion. METHODS: We selected 15 patients with acute brainstem stroke. We took serial fundus photographs and body pictures in upright position at various times after the stroke. We also determined the deviations of patient's SVV. The data measurement for this investigation ranged from day 2 to day 47. RESULTS: Eight of ten patients with lateral medullay infarction showed ipsiversive tilt of SVV and OT. Among four patients with pontine infarction, one showed ipsiversive tilt and three contraversive. One patient with midbrain hemorrhage showed cotraversive tilt. The resolution of OT and the tilt of SVV in medullary lesions occurred over the periods ranging from 7 days to more than 47 days and was slower in patients with upper brainstem lesion than lower brainstem lesion. The directions of head tilt in our patients, especially with medullary lesions, were rather different from the previous reports. CONCLUSION: The vestibular dysfunction by the brainstem lesions disturbs the eye and head stabilization and also distorts the perception of the subjective vertical in space. The direction of OT and the tilt of SVV is ipsiversive in lower brainstem lesion and contraversive in upper brainstem lesion. But head tilt is contraversive in most lower brainstem lesion as well as upper brainstem lesion. Large-grouped study for the direction of head tilt is thought to be needed. These signs are compensated in the course of clinical recovery.