Surgical management of Helveston syndrome (triad of A- pattern exotropia, superior oblique overaction and dissociated vertical deviation) using 'Four Oblique' procedure.

Purpose: To report the surgical outcomes in six patients of Helveston syndrome using a "four oblique" procedure. The popular methods for surgical management include superior rectus recessions alone or combined with superior oblique tenectomy. However, large angle exotropia correction would entail a higher risk of anterior segment ischemia when the superior rectus needs to be operated along with the horizontal recti. Hence, we evaluated the long-term results of this uncommon procedure. Methods: This was a retrospective review of six patients diagnosed to have manifest dissociated vertical deviation (DVD) with A pattern exotropia with bilateral superior oblique over action. All patients underwent horizontal muscle recessions/resections for exotropia along with bilateral posterior tenectomy of the superior oblique with inferior oblique anterior transpositioning. Results: The median age was 10 years (Range 5-26 years). The mean postoperative follow-up was 26 ± 14.02 months (Range 12-48 months). The mean reduction in exotropia was from 36.5 ± 21.06 PD (Range 15-65 PD) to 6.1 ± 3.06 PD (Range 3-10 PD). The procedure corrected the A pattern from a mean 23 ± 7 PD (Range 15-35 PD) to 7.6 ± 3.2 PD (Range 3-10 PD). The average DVD in the right eye reduced from 14 ± 4.3 PD (Range 8-20 PD) to 5.3 ± 1.2 PD and in the left eye from 14.33 ± 3.6 PD (Range 10-18 PD) to 4.1 ± 1.1 PD. The DVD asymmetry reduced from 6.33 ± 3.4 PD to 1.5 ± 1.3 PD. Conclusion: "Four oblique" procedure with horizontal muscle surgery seems to be an effective method for significantly correcting the A pattern as well as reducing the DVD with good long-term outcome in our case series.

Tenectomy and Posterior Tenectomy of the Superior Oblique for Superior Oblique Overaction

PURPOSE: The authors of the present study compared the effects of tenectomy and posterior tenectomy of the superior oblique for treating superior oblique overaction (SOOA). METHODS: The records of 30 eyes of 19 patients who underwent tenectomy or posterior tenectomy of the superior oblique alone or in combination with surgery on other horizontal rectus muscles from April 2005 through November 2010 were reviewed. The review was performed in 3 patients who underwent unilateral superior oblique tenectomy, 5 patients who underwent unilateral superior oblique posterior tenectomy, 3 patients who underwent bilateral superior oblique tenectomy, 6 patients who underwent bilateral superior oblique posterior tenectomy, and 2 patients who underwent superior oblique posterior tenectomy and tenectomy. RESULTS: The mean age of the patients was 14.2 years, and the mean follow-up period was 20 months. Through superior oblique tenectomy (11 eyes) and superior oblique posterior tenectomy (19 eyes), the amount of SOOA decreased from +2.27 to +0.09 and from +1.84 to +0.93, respectively. Except for 1 out of 11 eyes with superior oblique tenectomy, SOOA was completely corrected, although SOOA remained in 6 eyes after posterior tenectomy. Therefore, the correctional effects of the 2 methods differed; both procedures showed insignificant correctional effects on vertical strabismus. CONCLUSIONS: Superior oblique tenectomy has a superior long-term weakening effect; however, posterior tenectomy showed a comparable effect in the patient with moderate to severe SOOA. Both of these methods had few complications and are considered to be effective superior oblique weakening procedures.