[Results of inferior oblique muscle surgery in superior oblique paralysis]. / Les résultats de la chirurgie de l'oblique inférieur dans la paralysie de l'oblique supérieur.

The aim of this study was to evaluate the results of inferior oblique muscle recession in certain cases of superior oblique paralysis. Twenty-three patients with moderate hyperaction of the inferior oblique muscle, secondary to paralysis of the superior oblique muscle, in whom a recession of the ipsilateral inferior oblique was applied were enrolled in this study. These cases were selected among those with congenital superior oblique paralysis and infantile nontraumatic paralysis and those of unknown origin. Isolated recession of the inferior oblique muscle achieved a mean decrease in 8.69 +/- 2.05 D in hypertropia in the primary position. In 19 cases out of 23 (82.6%) who received isolated recession of the inferior oblique muscle, a vertical deviation equal to or less than 4 PD was obtained, showing the efficacy of this method in the surgical treatment of the cases with superior oblique paralysis and a moderate inferior oblique hyperaction.

Earthquake related startle reaction and its EEG correlates.

The acute effect of traumatizing events on the human brain has long been studied. The major obstacles to this endeavor have been the severity and the delay from time of exposure to the traumatizing events. To avoid these issues, EEG and clinical examinations of 18 healthy, drug-free subjects were performed 2 weeks after an earthquake occurred in Turkey in 1999. It was found, for the first time to our knowledge, that EEG parameters can predict startle response in acute stress reaction correctly in 100% of the cases. EEG measures of the reactivity to eyes opening were especially important in this regard.

Long-term results of bimedial rectus recessions in infantile esotropia.

BACKGROUND: Congenital esotropia has a deviation of 50 or more prism diopters (delta). Generally, surgical alignment of the eyes is the accepted treatment but surgical techniques differ. METHODS: A total of 54 patients were evaluated. Surgery was done at a mean age of 28 months. Bimedial rectus recessions up to 8 mm were performed. RESULTS: The mean preoperative deviation was 70 delta of esotropia. Our success rate with a uniform approach was 66.6%. CONCLUSIONS: Contrary to the selective approach for large angle congenital esotropia, we do not consider initial surgery on three or more muscles. Our method is quicker, simpler, less traumatic, and leaves the lateral rectus muscles unoperated for patients requiring a second surgery.

Cerebellar astrocytoma presenting with acute esotropia in a 5 year-old girl. Case report.

We encountered a 5-year-old girl with acute onset of alternating, comitant esotropia in the absence of diplopia and other neurologic findings. She did not have any refractive error and seen bilateral papilledemas in fundus examination, magnetic resonance imaging (MRI) of the head was performed. A large cerebellar astrocytoma and moderate hydrocephalus was identified and successfully resected. The onset of comitant esotropia in a child can be the first sign of a cerebellar tumor without any other neurologic signs and symptoms.

[The angle under anesthesia and elongation of the lateral rectus muscle in primary esotropia]. / L'angle sous anesthésie et l'élongation du droit externe dans les ésotropies primitives.

PURPOSE: In a group of 34 patients with esotropia, the anesthetic sign was studied in order to decide on the selection of the eye that should be initially operated. It is based on the examination of the variation between the angle while the patient is awake and the angle under general anesthesia applied with a definite protocole. The operated eye was always the most convergent or the less divergent one under general anesthesia. METHOD: During the operation the elongation of the medial and lateral recti belonging to the operated eye were systematically measured by Rapp-Roth myometer and Péchereau ruler. RESULTS: In 58% of cases, the examination under general anesthesia revealed an equivalent deviation of the dominated and dominant eyes form the midline. In 19% of cases convergence was obvious in the dominant eye while it existed in the dominated eyes in 23% of cases. CONCLUSION: It is concluded that a significant relationship exists between the basic angle and the variation of the angle under general anesthesia as well as between the basic angle and the elongation of the lateral rectus. Besides, this study points out the absence of relationship between the angle under general anesthesia and the elongation of the lateral rectus as well as the elongation of the two recti.

[Secondary hyperactivity of the contralateral oblique muscle after unilateral weakening of the inferior oblique muscle]. / Hyperaction consécutive de l'oblique controlatéral après affaiblissement unilatéral de l'oblique inférieur.

PURPOSE: This study was designed to analyze the consecutive overaction of the contralateral inferior oblique (IO) muscle after unilateral weake in procedure of the same muscle which is a well-known but not regularly studied phenomenon. MATERIAL AND METHODS: Unilateral weakening of overactive IO muscle was performed in a group of 27 patients with esotropia (14 recessions and 13 marginal myotomias). Eleven of these patients had unilateral overaction of the IO muscle. In the remaining 16 patients the overaction was highly asymmetric. RESULTS: Postoperatively we observed only one consecutive overaction of the contralateral IO in patients with unilateral overaction. However, this condition was observed in 11 of 16 patients with asymmetric IO overaction. CONCLUSION: The innervational pathogenesis of this phenomenon is a subject of discussion. The authors emphasize the necessity of the clinical examination in order to identify the bilateral asymmetric forms and to neutralize them by convenient surgical procedures.

Brain SPECT evaluation of the visual cortex in amblyopia.

UNLABELLED: In amblyopia, the number of visual cortical neurons are reduced and abnormal or absent sensitivity to retinal light stimulation of the amblyopic eye is demonstrated. Ten amblyopic patients were studied to evaluate the response of the visual cortex to visual stimulation. METHODS: All patients with unilateral amblyopia received 500-550 MBq 99mTc-HMPAO during visual stimulation. Strobe light flashing was used as the stimulus for five patients and a checkerboard pattern reversal was used in the other five patients, closing one eye. For both groups a 2-Hz frequency was used. One week later, the same procedure was repeated with the opposite eye closed. SPECT images were reconstructed with prefiltering techniques and sliced along the orbitomeatal line. RESULTS: For all patients, the amblyopic eye demonstrated less radioactivity in the visual cortex than in the normal eye. The mean cerebral-to-cerebellar ratios were 0.95 +/- 0.05 and 1.09 +/- 0.07 for amblyopic and normal eyes, respectively (p < 0.0001). CONCLUSION: Visual cortex response of the amblyopic eye to light stimulation was severely reduced when compared to the normal eye.