No abstract available.
Strabismus*

No abstract available.
Strabismus*

Anterior transposition of inferior oblique muscle(ATIO) is known to an effective procedure for correcting marked overaction of inferior oblique muscle. However, depression in abduction and elevation deficiency in primary and abduction positions have occurred without adherence syndrome after this procedure. To avoid these complications, the author modiffied ATIO by transposing only the anterior portion of inferior oblique muscle at 2mm anterior to the temporal insertion site of inferior rectus, and placing the posterior portion of muscle just posterior to the insertion site of inferior rectus. Modified ATIO was performed in 4 cases of inferior oblique overaction(IOOA) with dissociated vertical deviation(DVD), 2 cases of unilateral IOOA withcontralateral superior oblique overaction(SOOA) and 5 cases of superior oblique palsy(SOP) Knapp class IV. They were observed for over 6 months (6~18 months). Three of 4 cases of IOOA with DVD were improved but adherence syndrome occurred in one case and depression in abduction occurred in another case. In 2 cases of unilateral IOOA with contralateral SOOA, hypertropia was decreased from 20delta and 2delta respectively, after the procedure. In 5 cases of SOP Knapp class IV, preoperative hypertropia was 20delta-40delta in primary position. After modified ATIO, hypertropia was 0delta-20delta . The correction effect was 12delta-35delta , with an average of 18.4delta in primary position. In 4 of 5 cases, hypertropia was corrected within 10delta in primary position. Modified ATIO is an effective procedure for unilateral IOOA with contralateral SOOA and SOP Knapp class IV as a single muscle surgery.
Depression ; Strabismus

A study on 96 children with squint of which cross-eyed (74) treated in the institute of ophthalmology during 1993-1996 has shown that the merely exercise treatment recovered the biocular vision well for squint, for the latent squint at high grade, alternant squint at high grade, local accommodative cross eyed and concomitant squint at high grade, it should combine the exercise and balance surgical treatment.
Strabismus ; child

Plication of horizontal recti with many advantages in the treatment of strabismus has been applied by many authors in the world, but not yet in Vietnam. Objectives: to evaluate the results of this surgery that applied in Vietnamese. Methods: Prescriptive, longitudinal prospective study that had been done in Hanoi National Institute of Ophthalmology from 9/2003 to 9/2004. Results: In postoperative period, 83.3% of cases with exotropia and 89.6% of cases with esotropia are well corrected after 6 months, 100% of operated eyes are well healed with a smooth conjunctive scars and 52.62 % of operated patients have got a full binocular vision after 3 months following up. The rate of the eyes with suspected amblyopia is reduced from 18.8% to 9.8%, with moderate amblyopia is also reduced from 8.8% to 2.4% by 6 months postoperatively, but the rate of the eyes with severe amblyopia is not significantly changed after surgery. Conclusion: Plication of horizontal recti is a safe, effective method for correction of strabismus, especially when it is necessary to do surgery on many extra-ocular muscles in the same eye.
Strabismus ; Therapeutics

Numerous authors published tables showing the amount of strabismus surgery and the effectivity. Although Scobee and Knapp etc. stressed the difficulty of making an accurate prediction of strabismus surgery. the standardized formula of the surgical treatment of strabismus has long been the ambition of ophthalmologist. Author agreed with the opinion of Dyer who provided the ophthalmologist with excellent tables suggesting combinations of muscles and amount of surgery to correct various types of strabismus and so 132 cases of comitant horizontal strabismus treated surgically with Dyer method at Kong Eye Clinic from August 1975 to July 1976 were analyzed. With author's data. this paper present a mathematical formula to estimate the amount of strabismus surgery.
Muscles ; Strabismus*

PURPOSE: To investigate the effect of illumination on stereoacuity and to evaluate adequate illumination for each stereotest. METHODS: We measured stereoacuity by Titmus stereotest, TNO stereotest, Lang stereotest in normal group of 40 cases and strabismus group of 26 cases with five levels of illumination. The statistical analysis was performed to compare the mean stereoacuity between different levels of illumination using Student t-test. RESULT: In Titmus stereotest, stereoacuity improved as illumination increased up to 60 lux, which was statistically significant (P< 0.05). In TNO stereotest, stereoacuity significantly improved as illumination increased up to 200 lux in normal group (P< 0.01), and up to 60 lux in strabismus group (P=0.01). In Lang stereotest, 100% of normal group passed the test under 20 lux or more, and 100% of strabismus group passed the test under 60 lux or more. DISCUSSION: The illumination of 60 lux or more was required for Titmus stereotest and 200 lux or more for TNO stereotest, which was sufficient with the room illumination. Lang stereotest is less influenced by illumination and could be performed under lower illumination than other stereotests.
Humans ; Lighting ; Strabismus

PURPOSE: To compare the surgical methods for the treatment of sub-V pattern intermittent exotropia. METHODS: Sub-V pattern intermittent exotropia is defined as 8-15 prism diopters (PD) less horizontal deviation in downgaze than in upgaze. The present study included 65 patients who underwent a standard recession procedure of the lateral rectus muscle (group I), oblique muscle surgery (group II) or vertical transposition of the horizontal rectus muscle (group III) and who were followed up for six months after the surgery. RESULTS: Surgical success was defined as vertical incomitance < or =5 PD; the success rate was 92% (23/25) in group I, 88.8% (16/18) in group II and 86.4% (19/22) in group III. Surgical success of the horizontal strabismus was defined as horizontal deviation < or =10 PD at primary position; the success rate was 87.9% (51/58) in the patients with vertical incomitance less than 5 PD, and 42.9% (3/7) in the patients with vertical incomitance greater than 6 PD. There was statistical significance in the success rate of horizontal strabismus according to the decrease in vertical incomitance (p=0.01). CONCLUSIONS: There was no statistical significance of the difference in success rates of horizontal strabismus surgery regardless of vertical transposition of the horizontal rectus muscle or oblique muscle surgery. There was statistical significance in the difference in success rates of horizontal strabismus according to the reduction in vertical incomitance.
Exotropia ; Humans ; Muscles ; Strabismus

In 7 patients with "A" pattern strabismus with superior oblique overaction, we performed superior oblique posterior tenotomy and tenectomy(PTT) and horizontal rectus muscle surgery for horizontal strabismus, uni- or bilaterally, and analysed the status in degree of postoperative correction of "A" pattern, horizontal and vertical deviation in the primary position for availability of PTT in correction of superior oblique overaction. The average correction of "A" pattern was 10.4 prism diopter(PD). 6 of 7 patients showed eso- or exotropia under 6 PD in the primary position. Two of four patients in bilateral surgery and 2 of 3 patients in unilateral surgery showed the change of vertical deviation in the primary position but there were no problems cosmetically except one. From these results, we think that posterior tenotomy and tenectomy of superior oblique muscle is one of the useful methods for correction of superior oblique overaction in "A" pattern strabismus.
Exotropia ; Humans ; Strabismus* ; Tenotomy*

Hang-loose technique(HLT) is a reliable recession method in strabismus surgery. However, the loop length and the parallel of the anterior muscle border may not be sustained when the muscle was recessed behing the equator. This study was designed to assess the postoperative status of the large-recessed superior rectus muscle using the HLT and a modification of HLT(M-HLT) respectively in rabbits. Some of the recessed muscles with both techniques showed forward creeping. The average creeping was 0.5 mm on M-HLT and 1.1 mm on HLT in 7 mm recession group, and the difference was statistically significant(p=0.023). In 8 mm recession group, the average creeping was 1.0 mm on M-HLT and 1.8 mm on HLT. The difference was statistically significant(p=0.012). Although the parallel of the anterior muscle border was better on HLT than on M-HLT, the difference was not significant statistically. According to our result, M-HLT may be an useful alternative method in the cases of large recession with HLT.
Muscles ; Rabbits* ; Strabismus