Superior Oblique Overaction Research Articles

Horizontal mattress technique for superior oblique suture spacer

Superior oblique tendon overaction and Brown syndrome have been managed surgically by means of tenotomy/tenectomy, use of a silicon expander, and elongation with autologous fascia lata. These solutions are problematic with respect to corrective precision, injury and complications, or surgical difficulty. We present a simple "mattress" suture spacer technique that allows a precise and secure intraoperative adjustment.

Anomalous Scleral Insertion of Superior Oblique in Axenfeld-Rieger Syndrome

Axenfeld-Rieger syndrome (ARS) is associated with ocular and systemic anomalies. PITX2 is known to be a major controlling gene in the pathogenesis of ARS and is associated with differentiation in both the neural crest and mesoderm during eye development.A 4-year-old girl with bilateral ARS had 20 prism diopters (PD) of exotropia with 30PD of A- pattern deviation, more than 20PD of dissociated vertical deviation (DVD), and severe superior oblique overaction (SOOA). During surgery we observed that the SO inserted more posteriorly than normal.We believe this finding is one of the abnormal manifestations of the development of the extraocular muscles in ARS.

Reunion of the Rabbit Superior Oblique Tendon After Weakening Procedures

PurposeTo investigate the degree of reunion in rabbit eyes of the superior oblique tendon after several surgical weakening procedures.MethodsA total of 32 rabbits (64 eyes) were used in this study. The rabbits were randomly assigned to four groups, eight rabbits (16 eyes) in the tenotomy group, eight rabbits (16 eyes) in the tenectomy group, eight rabbits (16 eyes) in the disinsertion group and eight rabbits (16 eyes) in the recession group. The degree of reunion or reattachment of the superior oblique tendon on the globe were examined on four eyes in each group at postoperative weeks two, four, six and eight.ResultsAt eight weeks, the newly created insertion site remained at the same site in all eyes in the recession group, and the distal end of the superior oblique tendon was reattached at the medial border of the superior rectus muscle in all four eyes in the tenotomy and disinsertion groups, and in three of four eyes in the tenectomy group.ConclusionsFrom this experimental study, it was speculated that superior oblique recession is more effective than other superior oblique weakening procedures. This result could be helpful in the prediction of time of recurrence for superior oblique overaction after superior oblique weakening procedures.

Z-tenotomy of the superior oblique tendon and horizontal rectus muscle surgery for A-pattern horizontal strabismus

Few studies have investigated combined surgeries for horizontal deviation and A pattern caused by superior oblique overaction (SOOA). This study presents our experience with combined surgery and examines the effect of the type of strabismus and prior surgery on outcome. The medical records of patients who underwent combined surgery for horizontal deviation occurring with A-pattern misalignment from 2000 through 2004 were reviewed. The procedure consisted of horizontal extraocular muscle recession or resection with superior oblique Z-tenotomy. The criteria for surgical success were horizontal deviation at primary gaze of </=10(Delta), A pattern of </=8(Delta), and SOOA of </=1.0. The study group included 28 patients with a mean age of 13.4 years. Thirteen (46.4%) had A-pattern esotropia; 15 (53.6%) had A-pattern exotropia. Fifteen (50%) had undergone previous surgery. The success rate for the whole group was 60.7%. There was no statistically significant difference in success rate between patients with esotropia (53.8%) or exotropia (66.7%) (p = 0.48) or between patients in whom the combined procedure was the primary (71.4%) or secondary (50.0%) treatment (p = 0.246). Measurements of horizontal strabismus remained stable throughout follow-up in the esotropia group but were unpredictable in the exotropia group. The success rate of combined horizontal deviation/A-pattern surgery is unaffected by type of horizontal deviation or prior surgery.

Super oblique tendon elongation with fascia lata

Superior oblique lengthening with a silicone retinal band is used to treat superior oblique overaction (SOOA); however, secondary infection, implant extrusion, orbital cellulitis, and adhesion may occur. We present a method of superior oblique tendon elongation in which autogenous fascia lata is used to decrease the likelihood of these complications. Six patients (5 female, 1 male) aged 7-22 years (mean, 17 years) with 40-85(Delta) exotropia and SOOA (range, +2 to +4; mean, +3.5) underwent bilateral superior oblique lengthening with insertion of fascia lata. In the last 2 cases, the values of elongation were augmented by 2 mm. Fascia lata was harvested through a linear incision on the lateral aspect of the patient's thigh. Postoperatively, correction of A-pattern exotropia to within 10(Delta) was achieved in 66% of the cases as well as correction of SOOA to within +1 in 58% of the cases, with a follow-up of 9 months. All patients with +2 to +3 SOOA (3 cases) were fully corrected, whereas those with +4 SOOA (9 eyes) had residual overaction of +1 to +3. In the 4 eyes with augmented elongation, residual SOOA was between 0 and +2. No patient developed superior oblique palsy. Autogenous fascia lata may be used as an alternative to a silicone band for superior oblique lengthening. Our results were comparable with published results for the silicone band, with a lower rate of overcorrection. The improved biocompatibility makes it likely that autogenous fascia lata will have a lower complication rate than with a silicone band.

Evaluation of subjective and objective cyclodeviation following oblique muscle weakening procedures

To evaluate the subjective and objective cyclodeviational changes following different weakening procedures on superior and inferior oblique muscles. Comparative case series. In a prospective institution based study, 16 cases of A pattern horizontal strabismus having superior oblique overaction were randomized to superior oblique weakening procedures: either silicon expander or translational-recession. Similarly, 20 cases of V pattern horizontal strabismus with inferior oblique overaction were randomized for inferior oblique weakening procedures: either 10 mm Fink's recession or modified Elliot and Nankin's anteropositioning. Cyclodeviation was assessed subjectively with the synoptophore and objectively using the fundus photograph before surgery and 3 months postoperatively. Change in cyclodeviation was measured by subjective and objective methods. The index of surgical effect (ISE) was defined as the net torsional change postoperatively. The difference between the extorsional change induced by the two superior oblique procedures, silicone expander (-6 degrees ) and translational recession (-11.3 degrees), was statistically significant (P=0.001). Translational recession caused more extorsional change (ISE=296%) than silicone expander surgery (ISE=107%). The two inferior oblique weakening procedures, Fink's recession (+2.5 degrees) and modified Elliot and Nankin's anteropositioning (+4.7 degrees) produced equitable amount of intorsional shift with no statistical difference (P=0.93). Objective measurements were significantly more than the subjective measurements. Different weakening procedures on oblique muscles produce different changes in cyclodeviation, which persists even up to 3 months. Subjective cyclodeviation is less than the objective measurements indicating partial compensation by sensorial adaptations.

A case of A-pattern esotropia with dissociated vertical deviation with bilateral congenital ptosis

Dissociated vertical deviation (DVD) is an enigmatic strabismus entity for which various theories of causation have been proposed. Commonly seen in association with infantile esotropia, it responds unpredictably to surgical intervention hence fuelling theories for a supranuclear center defect albeit at the midbrain level. Cases of DVD associated with A- pattern eso or exotropia and superior oblique overaction have been reported, although rarely. We report a case of bilateral congenital ptosis associated with this complex. Not reported earlier, we hope this case may help in better understanding of the obscure etiology of this symptom complex.

Clinical Study of A-V Pattern Strabismus in Korea

Purpose: To assess the prevalence of A-V pattern strabismus and evaluate the clinical characteristics, surgical methods and outcomes. Methods: Among 825 patients who underwent horizontal strabismus surgery, the records of patients with A-V pattern strabismus were reviewed retrospectively. The prevalence and clinical characteristics of patients with A-V pattern strabismus were assessed and the surgical methods and outcomes of A-V pattern strabismus were evaluated. Results: Among 825 patients with horizontal strabismus surgery, 113 (13.7%) patients had A-V pattern. V exotropia was the most common (65.5%) and A esotropia was the least common (7.1%) pattern. A +1.9 inferior oblique overaction in 92.8% of the V-pattern patients and a +1.5 superior oblique overaction in 70.0% of the A pattern patients was found. Among the 113 patients, 64.6% patients underwent oblique muscle surgery and 35.4% patients underwent vertical transposition of horizontal muscle. Vertical incomitance was significantly reduced after surgery in all types of A-V pattern strabismus (p

Anterior plagiocephaly with contralateral superior oblique overaction

Anterior plagiocephaly is a craniofacial anomaly related to premature unilateral synostosis. We present three cases of anterior plagiocephaly with contralateral superior oblique dysfunction. A detailed ophthalmic examination, including orthoptic assessment for the extraocular muscle misalignment, with appropriate radio-imaging was done in all the three cases. All of them showed a right-sided plagiocephaly, with overaction of the left superior oblique muscle, alternating exotropia and a dissociated vertical deviation. Two underwent surgical correction of squint. Both were well aligned after squint surgery. Plagiocephaly has been reported to simulate superior oblique muscle paresis. We report a rare occurrence of contralateral superior oblique muscle overaction in three children with anterior plagiocephaly.

Neuro-ophthalmologic findings in patients with rhombencephalosynapsis

Rhombencephalosynapsis is a rare, sporadic, posterior fossa malformation characterized by agenesis of the cerebellar vermis, dorsal fusion of the cerebellar hemispheres, and fusion of the dentate nuclei and superior cerebellar peduncles. Ophthalmologic findings in patients with rhombencephalosynapsis have not been described in detail. Optic nerve and chiasmal hypoplasia were reported in two patients. Strabismus has been noted in several patients; however, specific details were not provided. We describe the association of A-pattern strabismus and superior oblique overaction with rhombencephalosynapsis.

Surgical and Functional Results of Augmented Superior Oblique Muscle Z-tenotomy in Patients With Superior Oblique Overaction and Brown’s Syndrome

To compare the effectiveness of augmented superior oblique Z-tenotomy (SOZT) with fixed standard SOZT in canceling preoperative superior oblique overaction associated with A pattern anisotropia or V pattern in Brown's syndrome. Sixteen consecutive patients with superior oblique overaction or Brown's syndrome were treated by removal of a triangular piece of the superior oblique tendon near its insertion (augmented SOZT). Outcome was compared with 20 consecutive historical controls after standard SOZT. The decrease in superior oblique overaction in the right and left eyes and fundus intorsion and the collapse of A pattern anisotropia were more significant for patients with superior oblique overaction (P = .003, P = .007, P = .05, P = .0015, respectively) and patients with Brown's syndrome (P = .025, P = .03, and P = .05, respectively). No study patient with superior oblique overaction and A pattern anisotropia required reoperation compared with 5 of 14 controls (37.5%); rates for patients with Brown's syndrome were 0 for the study group and 3 of 6 (50%) for the control group. Augmented SOZT is superior to standard SOZT for correcting superior oblique overaction, intorsion, A or V pattern, and stereopsis. It is not associated with complications or reoperation. The size of the Z-tenotomy can be modified according to the intraoperative assessment to achieve symmetric results.

Uncorrectable Oblique Astigmatism and Impaired Binocular Vision in Case of Orbital Cherubism

A 22-year-old Japanese woman presented with diplopia of 12 years duration. She had a history of cherubism and had had repeated osteoplasties of the mandible. A left hypertropia with “A” pattern exotropia, bilateral superior oblique overaction, inferior oblique underaction, and incyclotorsion were present. The bilateral field of fusion determined by Goldmann perimetry showed diplopia in all fields except 10–20 degrees of the central field. Corneal topographic measurements showed characteristic oblique astigmatism due to the incyclotorsion. Titmus stereoscopic test showed depressed stereoacuity. The astigmatism was too large and axes too variable during eye movements to be corrected with spectacles, and the retraction of the lower lid prevented a proper fitting of contact lens. Thus, we conclude that orbital cherubism has many ophthalmological difficulties that are not easily correctable or treatable.

Superior Oblique Overaction With Limited Binocularity

&lt;h4&gt;EXCERPT&lt;/h4&gt; &lt;p&gt;A 6-year-old boy was referred to your office because his first grade teacher noticed that he holds his chin down when reading. In addition, he rotates his head from left to right while reading a line of text. Despite this, his parents report he is doing well at school and is in the top of his class. The parents did observe brief moments of a misalignment of the eyes when he was an infant, but this has not occurred for years.&lt;/p&gt; &lt;h4&gt;Responses to Last Issue’s Case&lt;/h4&gt; &lt;p&gt;To read last issue's case, please click &lt;a href="http://www.journalofpediatricophthalmology.com/showAbst.asp?thing=12536"&gt;here&lt;/a&gt;.&lt;/p&gt;

Effect of Posterior Tenectomy of the Superior Oblique on Objective and Subjective Torsion in Cases of Superior Oblique Overaction

To evaluate the effect of posterior tenectomy of the superior oblique on the correction of A-pattern, superior oblique overaction and the changes in torsion that occur in such cases. This prospective study included 15 consecutive cases of bilateral superior oblique overaction with an A-pattern of more than 20 PD, a difference of deviation between 25 degrees up-gaze and 35 degrees downgaze, and superior oblique overaction of 2+ to 3+ on a scale of 0 to 4+. Deviation was measured in the primary position, 25 degrees upgaze, and 35 degrees downgaze using the prism bar cover test, and torsion was measured using a synoptophore, the double Maddox rod test, and fundus photographs. Measurements were obtained preoperatively and postoperatively at 1 week, 1 month, and 3 months. All case-patients underwent a standard temporal route posterior tenectomy of the superior oblique by a single surgeon. Mean age was 11.2 +/- 4.2 years with 14 cases of A-pattern exotropia. Mean superior oblique overaction was 2.60 +/- 0.50 in the right eye and 2.26 +/- 0.45 in the left eye, which decreased postoperatively to 2.20 +/- 0.56 and 1.80 +/- 0.41, respectively. The index of surgical effect was 0.84 in the right eye and 0.79 in the left eye. Postoperatively, mean correction of the A-pattern was 17.53 +/- 5.82 PD (index of surgical effect, 0.7). Subjective measurement of torsion was more consistent with the synoptophore compared with the double Maddox rod test. Objective measurement of torsion (fundus photography) was higher compared with subjective measurement. Postoperatively, there was insignificant change in the amount of torsion in upgaze and primary position. Posterior tenectomy of the superior oblique results in significant and controlled weakening of the superior oblique and collapse of the A-pattern with a clinically insignificant change in the amount of torsion.

Treatment of Inferior Oblique Paresis With Superior Oblique Silicone Tendon Expander

Patients with inferior oblique eye muscle paresis may show hypotropia and apparent superior oblique muscle overaction on the side of the presumed weak inferior oblique (IO) muscle. We report 8 such patients successfully treated using unilateral silicone superior oblique (SO) tendon expanders. Eight consecutive cases over the course of 6 years from the authors' private practice are described. None had a history of head trauma or a significant neurologic event. All patients showed IO paresis by 3-step test, with incyclotorsion and SO overacton of the hypotropic (paretic) eye. Forced ductions of the hypotropic eye were normal in all cases, and the vertical strabismus was treated with placement of a 7- mm silicone SO tendon expander in the hypotropic (paretic) eye. Mean preoperative primary position hypotropia was 6.5 prism diopters (PD); mean postoperative was 0.5 PD. Seven of 8 patients had resolution of primary position hypotropia, whereas the eighth was reduced. Mean preoperative SO overaction was 3+; all patients had postoperative resolution of SO overaction. Of 4 patients with preoperative ocular torticollis, mean preoperative head tilt was 9.3 degrees; mean postoperative tilt was 2.9 degrees. Two patients' head tilts had resolved, the other 2 showed improvement. All patients showed preoperative incylclotorsion of the hypotropic (paretic) eye; inclyclotorsion resolved in all patients after the placement of a SO tendon expander. The silicone SO tendon expander effectively restores ocular alignment in IO paresis with apparent SO overaction. Associated ocular torticollis can also be improved.

Surgical results of patients with a-pattern horizontal strabismus

Purpose To investigate the surgical results of patients having horizontal strabismus with A-pattern associated with superior oblique overaction (SOOA). Methods Twenty patients with horizontal strabismus (12 exotropia [XT] and 8 esotropia [ET] with no previous strabismus surgery) with SOOA-associated A-pattern were analyzed retrospectively. Motor success was defined as a horizontal deviation of 8 prism diopters ( PD) or less, 6 PD or less of vertical deviation in all gazes, and no greater than 8 PD of A-pattern. Stereoacuity was measured using the Titmus test (Stereo Optical, Chicago, IL). Results Sixty percent of patients had successful results at the final examination. No significant difference was found between the XT and ET patients in preoperative and postoperative horizontal deviations in the primary position, A-pattern collapse, or success rate ( P > .05). Four patients had an induced postoperative vertical deviation. Among eight patients without stereoacuity preoperatively, four showed an average of 910 seconds of arc (40 to 3000 seconds of arc) after surgery. Conclusion Simultaneous surgery on the horizontal and SO muscles in patients with horizontal strabismus with SOOA-associated A-pattern can achieve a relatively high surgical success rate and restore binocular function.

The efficacy of superior oblique split Z-tendon lengthening for superior oblique overaction.

To evaluate the efficacy of superior oblique muscle split Z-tendon lengthening in the treatment of superior oblique muscle overaction with respect to normalization of superior oblique ductions and versions, reduction of A-pattern strabismus and correction of vertical deviations. In addition, to determine the incidence of complications of the procedure including overcorrection and the effect of the procedure on horizontal deviation. A retrospective review was performed of 19 patients who underwent superior oblique muscle split Z-tendon lengthening for A-pattern strabismus or significant vertical deviation associated with superior oblique overaction between June 1980 and September 1999. Ten males and 9 females were included, ranging in age from 2 to 45 years (mean: 9 years). Patients underwent either a unilateral or bilateral superior oblique tendon lengthening based on the patient's clinical picture. Ten of 11 patients (91%) who underwent unilateral tendon lengthening and 10 of 16 eyes (63%) that underwent bilateral superior oblique tendon had complete normalization of superior oblique action. Seven of 10 patients (70%) who underwent unilateral or bilateral tendon lengthening for a clinically significant A-pattern had the A-pattern completely eliminated or brought to a clinically insignificant level. All 8 patients who underwent a unilateral tendon lengthening for a clinically significant vertical deviation had reduction of the vertical deviation. There was no statistically significant effect of either the unilateral or bilateral procedure on horizontal deviation. The superior oblique muscle split Z-tendon lengthening procedure is highly effective for normalization of superior oblique muscle function and reduction of A-pattern strabismus and vertical deviations associated with superior oblique muscle overaction.

The efficacy of superior oblique split Z-tendon lengthening for superior oblique overaction

Purpose To evaluate the efficacy of superior oblique muscle split Z-tendon lengthening in the treatment of superior oblique muscle overaction with respect to normalization of superior oblique ductions and versions, reduction of A-pattern strabismus and correction of vertical deviations. In addition, to determine the incidence of complications of the procedure including overcorrection and the effect of the procedure on horizontal deviation. Methods A retrospective review was performed of 19 patients who underwent superior oblique muscle split Z-tendon lengthening for A-pattern strabismus or significant vertical deviation associated with superior oblique overaction between June 1980 and September 1999. Ten males and 9 females were included, ranging in age from 2 to 45 years (mean: 9 years). Patients underwent either a unilateral or bilateral superior oblique tendon lengthening based on the patient’s clinical picture. Results Ten of 11 patients (91%) who underwent unilateral tendon lengthening and 10 of 16 eyes (63%) that underwent bilateral superior oblique tendon had complete normalization of superior oblique action. Seven of 10 patients (70%) who underwent unilateral or bilateral tendon lengthening for a clinically significant A-pattern had the A-pattern completely eliminated or brought to a clinically insignificant level. All 8 patients who underwent a unilateral tendon lengthening for a clinically significant vertical deviation had reduction of the vertical deviation. There was no statistically significant effect of either the unilateral or bilateral procedure on horizontal deviation. Conclusions The superior oblique muscle split Z-tendon lengthening procedure is highly effective for normalization of superior oblique muscle function and reduction of A-pattern strabismus and vertical deviations associated with superior oblique muscle overaction.

The efficacy of superior oblique split Z-tendon lengthening for superior oblique overaction

The efficacy of superior oblique split Z-tendon lengthening for superior oblique overaction

Superior oblique overaction from local anesthesia for cataract surgery

Traumatic superior oblique dysfunction from cataract surgery appears to be rare, with only 3 reported cases of postoperative Brown syndrome1,2 and 1 reported case of postoperative superior oblique weakness.3 We are not aware of any prior reports of superior oblique overaction occurring after cataract surgery. We describe a patient with acquired superior oblique overaction as a cause of vertical strabismus after cataract surgery. Ocular torsion analysis was essential in localizing the malfunction to the superior oblique muscle. The most likely etiology is myotoxicity from inadvertent intramuscular injection of local anesthetic before cataract surgery.J AAPOS 2001;5:329-32.