Tomás Scalamandré Mendonça

Toxina botulínica no tratamento de estrabismo horizontal em crianças com paralisia cerebral

To evaluate the efficacy of botulinum toxin injection in the treatment of horizontal strabismus in children with cerebral palsy. METHODS: A group of 24 patients, age 6 - 156 months, with cerebral palsy and horizontal strabismus (17 esotropias ranging from 25 to 45 PD and 7 exotropias ranging from 20 to 45 PD) were treated with botulinum toxin (34 medial rectus and 14 lateral rectus muscles). The children underwent full ophthalmic examination. The injection treatment was performed after sedation using Mendoncas forceps. The follow-up was done after 7 days, 15 days and monthly. Deviation less or equal of 10 PD after 6 months of follow-up was considered successful. However, if patients did not achieve this result a second application could be performed. RESULTS: In the group of esotropia (n=17) 47.1% had successful results with only one application after two years of follow-up. All of these patients had previous deviation less than or equal to 35 PD. In the exotropia group a single injection was not sufficient to achieve successful result. The side effects included: subconjutival hemorrhage in 4 (16.7%) patients, transient vertical deviation in 4 (16.7%) and transient ptosis in 22 (91.7%). CONCLUSION: The use of botulinum toxin was a good alternative in the treatment of children with cerebral palsy and esotropia.

Comparação entre os métodos de injeção de toxina botulínica em músculo ocular externo com o uso do eletromiógrafo e com o uso da pinça de Mendonça

PURPOSE: To compare two methods of botulinum toxin A (BTA) injection into the extraocular muscle (EOM): the electromyographically (EMG) guided injection and the injection using Mendoncas forceps. METHODS: Twenty-nine (29) patients with strabismus and low visual acuity in one eye were examined at the Department of Ophthalmology of UNIFESP. They were divided into 2 groups - group I with 17 patients receiving the botulinum toxin A injection using Mendoncas forceps, and group II with 12 patients receiving the toxin with electromyographical guidance. The patients of both groups were examined on the 7th and 14th day after intervention and the outcome of both methods of botulinum toxin A injection were compared. Friedman and Mann-Whitney correlation tests were used in the statistical analysis of the data. RESULTS: Although the follow-up examinations on the 7th and 14th days showed a different behavior between both methods, there was no statistically significant difference between the mean values of the correction attained in both groups at the end of this study. CONCLUSION: No statistically significant difference was shown between the two groups. Mendoncas forceps can be a safe alternative to electromyography to locate an extraocular muscle for botulinum toxin A injection.

Bupivacaine and botulinum toxin to treat comitant strabismus

PURPOSE To evaluate the change in ocular motility and muscle thickness measured with ultrasonography after intramuscular injection of bupivacaine and botulinum toxin A. METHODS Eight patients (five female) were enrolled to measure ocular motility prior and 1, 7, 30 and 180 days after one injection of 2 ml of 1.5% bupivacaine and 2.5 U of botulinum toxin A in agonist and antagonist muscles, respectively, of eight amblyopic eyes. Muscle thickness was measured prior and on days 1, 7 and 30 after injection using 10-MHz ultrasonography (eyelid technique). RESULTS Mean change in alignment was 10 prism diopters after 180 days (n=6). An average increase of 1.01 mm in muscle thickness was observed after 30 days of bupivacaine injection and 0.28 mm increase was observed after botulinum toxin A injection, as measured by ultrasonography. Lateral rectus muscles injected with bupivacaine had a mean increase of 1.5 mm in muscle thickness. CONCLUSION In this study, a change in ocular motility was observed after 180 days of intramuscular injection of bupivacaine and botulinum toxin in horizontal extraocular muscles. Overall, there was an increase of muscle thickness in both botulinum toxin A and bupivacaine injected muscles after 30 days of injection when measured by ultrasonography. This change was more pronounced on lateral rectus muscles after bupivacaine injection.

Resultados da correçäo cirúrgica de esotropias de grande ângulo, em portadores de baixa de acuidade visual unilateral

Purpose: To evaluate the surgical outcome of large angle esotropia (minimum of 60 prism diopters ¾ pd) associated with unilateral low visual acuity (LVA) in which the surgical strategy was applied in order to operate only the non-fixating eye. Patients and Methods: We selected 17 patients with non-accommodative esotropia, LVA (VA£ 0,4 in the non-fixating eye with the better visual correction) and no previous treatment. Patients were classified as good result if they had a postoperative deviation of maximally 10 pd with binocular rotations of up to ¾2 of medial rectus and +2 of lateral rectus. Exotropia/esotropia between 10 and 15 pd or binocular rotations of ±3 were considered as a regular outcome. Deviations greater than 15 pd or binocular rotations of ±4 were included regarded as poor results. Results: Thirteen (76.4%) patients had counts fingers VA in the non-fixating eye, 2 (11.7%) achieved 0.1 and another two had 0.4. Three of them were also highly myopic (spherical equivalent of ¾6.00 diopters) in both eyes. Among the 17 patients, 12 (70.5%) had a good surgical outcome, 3 (17.6%) were regular and 2 (11.7%) poor. Conclusions: Strabismus surgery under topical anesthesia proved to be reliable in these special cases of unilateral LVA and often one can avoid surgery of the fixating eye by using this method.

Histological changes underlying bupivacaine's effect on extra ocular muscle

Abstract To determine the changes in the cross‐sectional area (CSA) of myofibers and their subtype distribution based on the myosin isoform expression after bupivacaine (BUP) injection in the EOM of rabbits and help the understanding of strabismus correction after BUP injection in the clinical practice. A total of 32 rabbits received 0.3 mL of 1.5% BUP in the superior rectus muscle (SR) of the right eye (OD) and were sacrificed at days 7, 28, 60, and 92. Additional eight untouched rabbits were included as controls. Hematoxylin and eosin staining was performed, and ImageJ software was used to measure CSA. Immunohistochemical analysis was performed to analyze the proportion of myofibers positive for myosin types 1 (slow), 2 (fast) and embryonic. Myofiber area measurement decreased 7 days after BUP injection [SR, 1271 ± 412 &mgr;m2 (control) to 909 ± 255 &mgr;m2 (day 7)] after BUP injection, followed by an increasing trend after 28 days and normalization after 92 days [SR; 1062 ± 363 &mgr;m2 (day 28), 1492 ± 404 &mgr;m2 (day 60), 1317 ± 334 &mgr;m2 (day 92)]. The proportion of slow myosin‐positive fibers increased in the 60‐day group (88.5% ± 16.2%). There was no statistically significant difference in fast myosin‐positive fibers. The inferior rectus of both eyes showed an increase in CSA. No increase of endomysial fibrous tissue was observed after 60 and 92 days of BUP injection. Bupivacaine, when injected into the SR of rabbits, initially decreases the fiber area followed by a transient increasing trend and normalization. There is a transient increase in the proportion of slow myosin‐positive fibers in the injected muscle. Muscle adaptation in untreated EOM was found with increased CSA. These findings help clarify the clinical effects of BUP in extraocular muscle. Graphical abstract Figure. No Caption available. HighlightsCross sectional area and myofiber subtype distribution after Bupivacaine injection.Initial necrosis, increased cross sectional area followed by normalization in injected muscles.Extraocular muscle showed increased slow myosin proportion in bupivacaine injected muscles.Not injected muscles showed an adaptation with increased cross‐sectional area.

Prevalence of refractive errors in Möbius sequence

PURPOSE To assess the prevalence of refractive errors in Möbius sequence. METHODS This study was carried out during the Annual Meeting of the Brazilian Möbius Society in November 2008. Forty-four patients diagnosed with the Möbius sequence were submitted to a comprehensive assessment, on the following specialties: ophthalmology, neurology, genetics, psychiatry, psychology and dentistry. Forty-three patients were cooperative and able to undertake the ophthalmological examination. Twenty-two (51.2 %) were male and 21 (48.8%) were female. The average age was 8.3 years (from 2 to 17 years). The visual acuity was evaluated using a retro-illuminated logMAR chart in cooperative patients. All children were submitted to exams on ocular motility, cyclopegic refraction, and fundus examination. RESULTS From the total of 85 eyes, using the spherical equivalent, the major of the eyes (57.6%) were emmetropics (>-0.50 D and <+2.00 D). The prevalence of astigmatism greater than or equal to 0.75 D was 40%. CONCLUSION The prevalence of refractive errors, by the spherical equivalent, was 42.4% in this studied group.