New strabismus surgical techniques.

Five new strabismus surgical procedures were developed by the authors and were presented as a workshop at the AAPOS annual meeting of the American Association for Pediatric Ophthalmology and Strabismus. They are summarized here to introduce these methods to the reader and provide surgeons with more options in approaching difficult strabismus problems. Diagnosis and correction of consecutive strabismus attributable to stretched scar is discussed. The pulley posterior fixation procedure is a unique approach to correct high accommodative convergence or to augment a maximal medial rectus recession. Diagnosis and repair of the partial avulsion (flap tear) of a rectus muscle allows correction of some restrictive strabismus following blunt trauma. The nasal myectomy of the inferior oblique muscle corrects persistent inferior oblique overaction without sacrificing the tether effect gained by a previous anterior transposition of the inferior oblique. The full advancement of the superior oblique tendon offers another option to strengthen a weak superior oblique muscle.

Long-term study of accommodative esotropia.

PURPOSE: This study aimed, using a large sample size, to determine the long-term results of standard treatment of accommodative esotropia and identify predictors of outcome while minimizing bias in data collection and analysis. METHODS: Data from all the files of a large, long-established pediatric ophthalmology practice were collected and analyzed using a masked protocol. The study included every esotropic patient who had been prescribed glasses. Criteria for patient inclusion were designed to conform to earlier studies by the authors. RESULTS: The database totaled 1307 patients, of who 354 met inclusion criteria. A greater difference between near and distance esodeviation (AC/A relationship) correlated with a higher rate of deterioration of accommodative esotropia control (P < 0.0001). Deterioration also positively correlated with earlier age of onset (P < 0.0001), inferior oblique overaction (P = 0.0005), and amblyopia (P < 0.005). CONCLUSIONS: This study demonstrates that a high AC/A relationship increases the likelihood of deterioration of accommodative esotropia, supporting the earlier studies, as well as the accuracy of this database. It also represents a new model for the utilization of clinical trials' bias-reduction principals in the analysis of retrospective data.

Presumed sinus-related strabismus.

PURPOSE: To determine whether sinus disease may cause acquired strabismus. METHODS: Patients with idiopathic acquired (nonaccommodative) esotropia and/or hypotropia were questioned in detail about possible contributing factors (trauma; family history of strabismus; thyroid, neurologic, or rheumatologic disorders). Acute versus chronic onset was ascertained. Those without obvious cause of strabismus were investigated for possible sinus disease with sinus computed tomographic scan and otolaryngologic consultation. RESULTS: Over a period of 5 years, 59 patients were identified with sinus disease that correlated to their strabismus pattern(s). Twenty-three had "possible" sinus-related strabismus. They had sinus findings that correlated with the strabismus pattern (eg, hypotropia and adjacent maxillary sinus disease). Twenty-six had "likely" sinus-related strabismus. These patients had additional features, such as their own recognition that strabismus worsened along with sinus symptoms, or unusually severe sinus disease. Ten were diagnosed with "very likely" sinus-related strabismus. They had strong correlation between treatment of sinus disease and strabismus improvement. Eighteen patients required sinus surgery owing to failure of medical control. Age at onset of strabismus ranged from 6 months to 81 years. Forty patients required strabismus surgery. All had restriction of motility on forced duction testing under anesthesia. Control of sinus disease combined with range-of-motion eye exercise improved symptoms in 19 who did not require strabismus surgery. CONCLUSIONS: Occult sinus disease may cause acquired strabismus. Perhaps sinusitis leads to inflammation and secondary contracture in adjacent extraocular muscles. Although difficult to prove owing to the high frequencies of both strabismus and sinus disease, the association between the two may prove significant to strabismus treatment and long-term control.

Long-term study of accommodative esotropia.

PURPOSE: Previous studies of accommodative esotropia have been hampered by bias-prone methods of data collection and analysis and by small sample size. The studies have conflicting conclusions, causing uncertain results. This study aims to determine long-term results of standard treatment of accommodative esotropia and identify predictors of outcome, while minimizing bias in data collection and analysis, using the largest possible sample size. METHODS: A research assistant collected data from all files of a large, long-established pediatric ophthalmology practice (M.M.P.). The assistant was given standardized collection forms that allowed inclusion of all patient data points over all visits. The assistant was masked as to study goals. She was instructed to include any patient with esotropia who had been prescribed glasses during treatment. Descriptive terms were converted to code numbers. A second, similarly masked research assistant entered data into a computerized database. Criteria for patient inclusion were designed to conform to earlier studies by I.H.L. and M.M.P. and were implemented by computer. RESULTS: The database totaled 1,307 patients (747,717 data points). Of these, 354 qualified for this analysis. A greater difference between near and distance esodeviation (AC/A relationship) correlated with a higher rate of deterioration of accommodative esotropia control (P<.0001). Deterioration also positively correlated with earlier age at onset, inferior oblique overaction, and amblyopia. CONCLUSIONS: This study agrees with our previous findings that a high AC/A relationship increases the likelihood of deterioration of accommodative esotropia, thus confirming the integrity of the database. This unique, unbiased dataset will be used for future analyses of esotropia.

Flap tear of rectus muscles: an underlying cause of strabismus after orbital trauma.

PURPOSE: To present an avulsion injury of the rectus muscle after orbital trauma, usually the inferior rectus, and detail its diagnosis and operative repair. METHODS: Forty-three patients underwent repair of flap tears of 62 rectus muscles. During surgery, we found the muscle abnormality was often subtle, with narrowing or thinning of the remaining attached global layer of muscle. The detached flap of external (orbital) muscle was found embedded in surrounding orbital fat and connective tissue. Retrieval and repair were performed in each case. RESULTS: The causes of orbital trauma were as follows: orbital fractures (15 patients), blunt trauma with no fracture (11 patients), suspected trauma but did not undergo computerized tomographic scan (12 patients), and status after retinal detachment repair (5 patients). Of note, 15 of the 43 patients (35%) underwent repair of the flap tear alone, without any additional orbital or strabismus surgery. Diagnostically, the predominant motility defect in 45 muscles was limitation toward the field of action of the muscle, presumably as a result of a tether created by the torn flap; these tethers simulated muscle palsy. Seventeen muscles were restricted away from their field of action, simulating entrapment. The direction taken by the flap during healing determined the resultant strabismus pattern. All patients with gaze limitation toward an orbital fracture had flap tears. The worst results after flap tear repair were seen in patients (1) who had undergone orbital fracture repair before presentation, (2) who had undergone previous attempts at strabismus repair, and (3) who had the longest intervals between the precipitating event and the repair. The best results were obtained in patients who underwent simultaneous fracture and strabismus repair or early strabismus repair alone. CONCLUSIONS: Avulsion-type flap tears of the extraocular muscles are a common cause of posttraumatic strabismus. Early repair produces the best results, but improvement is possible despite long delay.