and 4% had dubious binocular function. Only two patients pro-ceeded to surgery after multiple injections, the first after 40injections and the second after 27. Conclusion: Treatment ofstrabismus with Botulinum Toxin on a long-term basis is prac-ticable and valuable in patients with poor binocular potential andcomplicated or multiple previous strabismus operations. A trendto fewer injections with time was observed and no significantadverse effects were seen with long-term treatment.

Can occupational therapy improve vision skills associatedwith reading/writing? Cintia F. Gomi, Howard Taras, DavidB. GranetIntroduction: Occupational therapists (OT ) from the largestschool system in San Diego evaluated a new intervention todetermine whether motor skills also impact vision skills asso-ciated with reading and handwriting. Methods: OTs workedwith 52 general education first-grade students and 20 studentsin special education. They developed and applied a 12 weekprogram working on gross- and fine-motor coordination. Pre-and postintervention testing included handwriting samplesand standardized tests of Eye Movements and Control (fixa-tion, saccades, visual pursuits) and of Eye Teaming (vergences,fusion) for general education students. For special educationstudents tests were as follows: Eye Movements and Control(fixation and visual pursuits), Developmental Eye Movementtest, and Children’s Handwriting Evaluation Screening. Con-sultants from UCSD departments of Ophthalmology andCommunity Pediatrics were asked to analyze their results.Results: For special education students, a statistically signif-icant improvement was noted on the Eye Movement test forfixation and for accuracy of visual pursuits. In general educa-tion classes the total score for saccades and visual pursuitsshowed a statistically significant improvement. Scores for thehandwriting sample showed an improvement in legibility, lineapproximation, proportion, and spacing. Discussion: Al-though this project has several limitations, the data suggestthat working on motor coordination might also affect eyemovements. It is unclear however if these changes are relatedto the improvement seen in the handwriting samples, viceversa, or are unrelated. Conclusions: Just as increased readingfluency has been demonstrated to result in an improvement inoculomotor strategies, it may be that improved motor skills dothe same. Much work remains to be done in this intriguingfield.

The connective tissue power of extraocular muscles.Ossama M. HakimIntroduction: Eye movements have long held a fascination forclinicians, neuroanatomists, neurophysiologists, and recently,bioengineers. Our aim was to study ocular motility after extraoc-ular muscle (EOM) disinsertion. Methods: Forty strabismussurgeries were done for 40 adult volunteers (20-45 years). Allsurgeries were completed under either topical anesthesia usinglidocaine 2% jelly or peribulbar sensory-motor differentialblocking anesthesia using ropivacaine 0.2%. These surgeries in-volved disinserting 64 rectus and 6 oblique muscles, after lockingthem using 6-0 vicryl. After disinserting each muscle, the patientwas asked to move his eye in the field of action of this muscle andeye movement was recorded as normal, reduced, or absent. Re-sults: Normal eye movement was attained after disinserting 50rectus muscles (87%), while the other 14 rectus muscles (13%)showed reduced eye movement. On the other hand, the six

oblique muscles (100%) gut normal eye movement after disin-sertion. None of the muscles showed absent eye movement afterdisinsertion. Discussion: The unexpected, strong, persistence ofeye movement in the direction of action of the disinserted musclesignifies the anatomic insertion not only occurs at the point atwhich the muscle blends into the sclera but also involves the areaof muscle attachment to the surrounding connective tissue. Athorough knowledge and management of these attachments maybe the key to successful strabismus surgery in some cases likeunexpected residual esotropia or exotropia and persistence ofdissociated vertical deviation after superior rectus recession.Conclusions: Orbital connective tissue is an important addi-tional locomotor system which requires special microsurgicaltechniques.

Clinical and electrophysiological characterization ofinfantile periodic alternating nystagmus. Richard W.Hertle, Leah Reznick, Dongsheng YangIntroduction: This study identifies the clinical and ocularmotility characteristics of infantile periodic alternating nys-tagmus (IPAN) and establishes the range of electrophysiologyand clinical characteristics. Methods: Of 1026 eye movementrecordings performed from 1998 to 2006 in 506 patients withINS, 78 with IPAN are the subjects of this report. Analysis wasperformed offline from digitized data. Variables analyzed in-cluded, age, sex, vision, ocular abnormalities, head position(AHP), cyclic null-zone-neutral-zone characteristics, symme-try, conjugacy, and waveforms. Results: Ages ranged from 3months to 76 years; 77% had abnormal vision in at least oneeye, and 90% had strabismus and an anomalous head posture.All had oculographic null and neutral positions; 77% hadbinocular asymmetry, and 10% showed consistent dysconju-gacy. Average foveation periods were longer, more “jerk” inthose patients with better vision. The periodicity of the cycleswas largely irregular, and the phases within a cycle wereasymmetric. The AHP was in only one direction in 45%. In allpatients the PAN waveforms had an increasing slow-phasevelocity in at least one phase of the cycle. Discussion: Theoccurrence of IPAN as part of INS is not as rare as previouslythought and is often missed because of long or (a)periodiccycles, associated strabismus, and inconsistent or no AHP.The AHP was dependent on, and could be predicted from, thewaveforms containing the longest foveation times. Conclu-sions: We will help the clinician clinically recognize IPAN inthe INS population as medical and surgical treatment out-comes may be influenced by this motility diagnosis.

Surgical implications of the superior oblique frenulum.Megumi Iizuka, MD, Burton J. KushnerIntroduction: The superior oblique frenulum is a fascialmembrane that prevents significant separation of the superiorrectus muscle and superior oblique tendon. In this case series,we measured the effect of severing this frenulum on therelative positions of the superior oblique tendon and superiorrectus muscle when recessed. Methods: In three patients, thesuperior rectus was disinserted and suspended 6, 8, 10, 12, and14 mm from its insertion. The posterior excursion of theanterior edge of the superior oblique tendon from the superiorrectus muscle insertion was measured before and after sever-ing the frenulum structure. Next, in four patients, the superioroblique tendon was disinserted at its insertion temporally. Itsexcursion from the temporal edge of the superior rectus mus-

Volume 11 Number 1 February 2007 Abstracts 79

Journal of AAPOS