Poor correlation between "fix-follow-maintain" monocular/binocular fixation pattern evaluation and presence of functional amblyopia.

PURPOSE: To assess the reliability of visual screening with fix- follow-maintain (FFM) method in early detection of amblyopia in children who are not able to cooperate in testing with Allen Figures or Snellen E-chart. METHODS: Followup records of 89 patients that were examined in our pediatric ophthalmology department between May 1996 and May 1999 were evaluated retrospectively. The visual acuities that were measured with FFM method at the first visit were compared with the visual acuity levels that were measured with the Snellen E-chart at later followup visits. Functional amblyopia was defined as a difference of 2 or more Snellen lines between the two eyes. RESULTS: Amblyopia was later definitively diagnosed on the E-chart in only 17 (32.6%) of the 52 eyes that were estimated to have a significantly lower visual acuity than the fellow eye with the FFM method. Sensitivity of the FFM method in diagnosing amblyopia was found to be 53.1% and the specificity was 38.5%. CONCLUSIONS: The use of the FFM monocular/binocular fixation pattern to determine visual acuity and the possible presence of amblyopia is so insensitive, and so unspecific, that its reliability is very low and the results of such testing are therefore virtually useless, if not medically hazardous. There is, therefore, a need to make more universally available more sophisticated tests of vision (preferential looking, VEP); where they are not available, further emphasis should be placed on Snellen equivalent vision testing as with Allen Cards, Tumbling E, HOTV Test, Lea Figures etc. so as to obtain an accurate direct visual acuity at as young an age as possible. Amblyopia treatment should not be initiated solely on the basis of FFM testing.

Superior oblique muscle palsy in a patient with orbital dermoid cyst.

We describe the clinical and radiologic findings and surgical outcome of an orbital dermoid cyst causing a superior oblique muscle palsy in a child. Superior oblique muscle palsy in childhood is most often congenital. Less common causes are trauma, vascular lesions, neoplasms, and infections.(1,2) The most common orbital lesions in children are dermoid and epidermoid cysts.(3-5) A dermoid cyst at the region of trochlea is suspected as the cause of superior oblique muscle palsy in our case. This unusual presentation of a dermoid cyst has not been reported previously.

Surgical treatment in nystagmus.

PURPOSE: To evaluate the effect of symmetric recession surgery on all four horizontal rectus muscles in the treatment of patients with congenital motor nystagmus and sensory nystagmus secondary to albinism, dyschromatopsia and degenerative myopia. METHODS: Prospectively, four patients with a diagnosis of congenital motor nystagmus and eight patients with sensory nystagmus were operated on. The amount of recession was determined according to the ocular alignment of the patients. Electronystagmographic recordings were conducted in every patient pre-operatively and post-operatively, as well as an ophthalmological examination. RESULTS: Mean age of the patients at the time of the first visit was 6.7 +/- 4.2 years (range 9 months to 14 years) and mean age at the time of operation was 8.3 +/- 2.7 years (range 6-14 years). In 8 cases an equal amount of weakening of the four horizontal recti was done, whereas in 2 cases more recession on the lateral recti due to exotropia and in 2 cases more recession on the medial recti due to esotropia was performed. Mean follow-up time was 15.8 months (min. 6 months, max. 28 months). Improvement in visual function was achieved in 7 patients. Amplitude decreased in 9 patients. One patient had a decrease in visual acuity due to progression of her primary macular degeneration. Improvement in head posture was seen in 3 patients and there was no change in the head posture in 2 patients. One patient acquired head posture after surgery. Restriction of motility was seen in none of the patients after surgery in spite of large amounts of recession. Recession of horizontal recti decreased nystagmus amplitude and frequency in 81.8% of patients. Improvement in visual function, measured as an increase in visual acuity in terms of Snellen lines, was achieved in 63.6% of patients. CONCLUSION: Symmetric recession of the horizontal rectus muscles is shown to be a successful procedure to perform in nystagmus patients, resulting in an increase in visual acuity and a decrease in nystagmus amplitude and frequency. It is a reliable alternative to the Kestenbaum operation and is easier to perform surgically.

Microstrabismus in monozygotic twins.

PURPOSE: To report microesotropia in twins as a unique example of the role of heredity in primary microstrabismus. METHODS: Clinical records of the examinations of monozygotic twins with primary microstrabismus were reviewed. RESULT: Microstrabismus with different clinical findings was present in monozygotic twins. The family history and personal history of the patients were not significant. CONCLUSION: Microstrabismus can be seen as primary ocular motility problem without previous infantile esotropia or anisometropia. Genetic factors as well as intrauterine environment and developmental factors may affect sensorimotor development of the infant and cause ocular motility problems. Both twins should be examined for ocular motility disorders even in the absence of complaints.

Results of pars plana vitrectomy in Behçet's disease.

The result of pars plana vitrectomy in Behçet's syndrome has been investigated in patients with vitreous hemorrhage and condensation. Surgery was performed in seven cases. All of the patients became more hypotonic after surgery, and phthisis developed in less than two years. It is suggested that pars plana vitrectomy should not be performed in Behçet's patients.