Observation of binocular vision after surgical corrections in V - pattern exotropia children / 国际眼科杂志(Guoji Yanke Zazhi)

AlM:To observe the changes of binocular vision in V-pattern exotropia children before and after surgical correction, and the effect of training in reconstructing the binocular vision after surgical corrections.METHODS: Sixty V-pattern exotropia children were enrolled in this study and were divided into three groups according to their age:group A (4~6 years old), group B (7~9 years old), and group C (10~12 years old), 20 cases for each group. Patients received routine refraction and ophthalmic examinations. Distance and near deviation were measured by prism-covering method and synoptophore. The simultaneous perception and fusion were examined with a synoptophore, and the stereacuity was measured with stereograms ( Titmus) . The children who didn’t reconstruct binocular vision function 1wk after surgery received binocular vision training. The data were recorded before and 1 , 2, 4, and 8wk after surgery. RESULTS: Binocular vision significantly improved among the children after surgery in group A and B ( P0. 05). CONCLUSlON: V - pattern exotropia children can benefit from early surgical correction and training after surgery in reconstruct binocular vision.

The Clinical Characteristics of V-Pattern Exotropia Without Inferior Oblique Muscle Overaction

PURPOSE: To compare the surgical outcome between V-pattern intermittent exotropia without inferior oblique overaction and comitant intermittent exotropia. METHODS: The authors of the present study investigated 15 patients (V-pattern group) who had standard horizontal surgery with half-tendon width vertical transposition and 36 patients (Comitant group) with unilateral rectus muscle recession/resection. Preoperative visual acuity, presence of amblyopia, abnormal head posture, stereoacuity, amount of exotropia, and duration of postoperative diplopia were recorded. Surgical success was defined as final alignment of orthophoria or less than 10 PD orthophoria. RESULTS: The frequency of good stereoacuity with 80 sec of stereoacuity or more was higher in the V-pattern group (73.3%) than in the Comitant group (33.3%) (Fisher's exact test, p = 0.01). One case of V-pattern showed consecutive esotropia for 1 year postoperatively. Exotropia recurred in 2 patients in the V-pattern group (13.3%), and in 4 patients in the Comitant group (11.1%) 1 year postoperatively. Surgical success rates were statistically significant higher in the V-pattern group (86.7%) as compared to the Comitant group (58.3%) on final follow-up (Fisher's exact test, p = 0.04). CONCLUSIONS: V-pattern exotropia patients without inferior oblique overaction who had standard horizontal surgery with half-tendon width vertical transposition showed a lower recurrence rate of exotropia than patients with comitant intermittent exotropia.

Secondary Superior Oblique Overaction after Inferior Oblique Muscle Myectomy in a Patient Misdiagnosed with Inferior Oblique Muscle Overaction

PURPOSE: To report a case of superior oblique muscle tenotomy in a patient with suspected bilateral inferior oblique muscle overaction. The patient showed secondary superior oblique muscle overaction and inferior oblique muscle underaction after inferior oblique muscle myectomy. CASE SUMMARY: The patient showed V-pattern exotropia with suspected bilateral inferior oblique muscle overaction. After bilateral lateral rectus muscle recession with bilateral inferior oblique muscle myectomy, the patient showed secondary esotropia and inferior oblique underaction. After the surgery, progressive secondary superior oblique muscle overaction continued and finally, a superior oblique muscle tenotomy was performed. After the superior oblique muscle tenotomy, the superior oblique muscle overaction was corrected but the inferior oblique muscle underaction continued. CONCLUSIONS: After an inferior oblique muscle myectomy, secondary superior oblique muscle overaction can develop. Thus, caution should be taken in diagnosing inferior oblique muscle overaction in patients who show minimally inferior oblique muscle overaction as well as the surgical methods chosen.

The Change of Deviation Angle according to Gaze Position in Exotropes with Inferior Oblique Overaction

PURPOSE: To determine the correlation between the grade of inferior oblique overaction and the change of deviation angle according to gaze position. METHODS: We classified 90 patients into 4 groups according to the grade of inferior oblique overaction. Deviation angle was respectively measured in upward, primary and downward position at far and the difference between them was analyzed. And we assessed the frequency of V and Y pattern and the concordance of deviating eye between at primary position and at upgaze. RESULTS: Mean bilateral sum of the IOOA was +3.58 and average of deviation angle was 33.64 PD in upward position, 27.82 PD in primary position and 24.72 PD in downward position. Difference of deviation angle between upward and primary position was 5.82 PD (P0.05). The frequency of V pattern exotropia was 17.6% in group A, 17.1% in group B, 50% in group C and 85.7% in group D while the frequency of Y pattern among V pattern was 100%, 66.7%, 75% and 25% respectively. The chief deviating eye or IOOA predominant eye at primary position diverged during upgaze only in 67% of patients. CONCLUSIONS: The larger the inferior oblique overaction, the more V pattern exotropia was observed and deviation angle was increased at higher IOOA groups. Overall exotropia patients with IOOA shows rather Y shape than V shape. And chief deviating eye was not always deviating eye at upgaze.