Dynamics of interhemispheric relations as a result of functional treatment in children with non-paralytic operated strabismus

Purpose. To study the dynamics of interhemispheric interactions in children with friendly strabismus as a result of functional treatment. Material and methods. The study included 135 children aged 6 to 8 (average 6.8±0.1) years with convergent non-paralytic operated strabismus in combination with hypermetropic refraction and 96 children of the same age in the control group (average 7.1±0.1 years) without ophthalmic pathology. In children with strabismus, the leading hand and dominant eye were determined before and after functional treatment. Characteristics of spatial perception were evaluated by copying of complex geometric shapes which were Taylor's (right-handed) and Ray-Osterritz's (lefthanded). Results. After functional treatment in the group of children with non-paralytic strabismus, along with improved binocular functions and improved performance of the Taylor and Ray-Osterritz tests, there was an increase in the number of ambidextrous children and a significant decrease in the number of left-handers (p<0.001). Conclusion. The increase in the number of symmetrical lateral phenotypes against the background of improved binocular functions and spatial perception characteristics as a result of functional treatment of children with non-paralytic strabismus indicates an improvement of their interhemispheric interactions and can be an additional criterion for the ef fectiveness of treatment. Key words: lateral phenotypes, interhemispheric asymmetry, functional treatment of strabismus

TUBB3 E410K Syndrome With Childhood-Onset Nonalcoholic Steatohepatitis

Context Nonalcoholic fatty liver disease (NAFLD) is becoming a major issue worldwide, even in children. Multiple parallel hits hypothesis has been suggested as progress of NAFLD, but the mechanism of NAFLD is not completely understood. β-Tubulin is essential in mitoses, neuronal migration, and axon guidance during neuronal development. Pathogenic variants in the TUBB3 gene were shown to be associated with a wide spectrum of neurological abnormalities, but not accompanied by hepatic complications, such as NAFLD. Objective This work aims to examine the association between TUBB3 mutation and nonalcoholic steatohepatitis (NASH). Methods An 11-year-old girl has been followed up as having atypical Möbius syndrome since infancy, as she was born with bilateral ptosis, paralytic strabismus, and facial weakness. At age 7 years, she was diagnosed with TUBB3 E410K syndrome by whole-exome sequencing. At age 10 years, her blood examination revealed elevated liver transaminase levels, which persisted for almost 2 years. She underwent liver biopsy, the results of which were suggestive of NASH. Results The expression of TUBB3 was absent, but that of tyrosine hydroxylase (TH) was present in the parenchymal nerve fibers of the liver. On the other hand, in comparison with an autopsy case of NASH and a normal control, these showed coexpression of TUBB3 and TH in the liver. Conclusion We report the first case of TUBB3 E410K syndrome accompanied by NASH. This case suggests that the TUBB3 mutation may be associated with the pathogenesis and progression of NASH in humans.

Clinical Factors Affecting Recovery Periods of Vascular and Idiopathic Acquired Paralytic Strabismus

Purpose: Clinical factors affecting the recovery period in patients with vascular or idiopathic paralytic strabismus were evaluated.Methods: This study involved a retrospective review of medical records of patients diagnosed with vascular and idiopathic acquired paralytic strabismus. Vascular paralysis was defined in cases of hypertension, diabetes mellitus, or cardiovascular disease. The angle of deviation and limitation of extraocular movement were evaluated at each visit. Recovery was defined as the absence of diplopia and complete resolution of limitation of extraocular movement. Factors affecting recovery success and recovery period were analyzed.Results: We retrospectively reviewed data of 145 patients consisting of 87 with vascular paralytic strabismus (cranial nerve [CN] III: 21, CN IV: 28, CN VI: 38) and 58 with idiopathic paralytic strabismus (CN IV: 20, CN VI: 24, CN III: 14). The recovery rate did not significantly differ between vascular (60.9%) and idiopathic (63.8%) groups (p = 0.15). The recovery period was longer in the vascular group (130.1 ± 145.1 days) than in the idiopathic group (92.6 ± 76.6) (p = 0.02). Age at onset was significantly associated with the recovery period in both vascular and idiopathic groups. In the vascular group, the recovery periods were 107.4 ± 74.8 days in CN III palsy, 97.2 ± 51.9 days in CN IV palsy, and 159.3 ± 194.1 days in CN VI palsy. The recovery period was significantly longer in patients with CN VI palsy (p = 0.03). Hypertension was significantly influencing the recovery period in patients with vascular CN VI palsy (odds ratio = 2.54, p = 0.01).Conclusions: The recovery period was longer in patients with vascular paralytic strabismus than in patients with idiopathic paralytic strabismus. Recovery rates were not significantly different between groups. In patients with vascular CN VI palsy, a history of hypertension was significantly associated with the recovery period.

Results of Using Different Modes of Presentation of Stereostimuli in the Study of Stereo Vision in Normal Children and in Children with Non-Paralytic Strabismus without Functional Scotoma

The work is devoted to one of the actual problems of current ophthalmology — creating effective methods of studying stereovision.The purpose — comparative analysis of the capability of stereoperception under conditions of using different regimes of alternating presentation of stereo stimuli with different characteristics in children with strabismus and in children without ophthalmopathology.Patients and methods. 294 school children — 167 children of the control group (without ophthalmopathology) and 127 children with non-paralytic strabismus without functional scotoma (FSS) were observed. We used stereostimuli with different characteristics in the following regimes of presentation: 1) the regime of simple monocular alternating (alternate presentation of an image for the right and left eye); 2) the regime having an “empty” interval (black background) between monocular phases; 3) the regime having a binocular phase (a binocular image containing details corresponding to the stimuli for the right eye and the left eye) between monocular phases.Results. It was found that the majority of children with non-paralytic strabismus, who are incapable of stereoperception with the classic Fly-test and Lang-test, can perceive the stereoeffect with alternating presentation of stereostimuli within individual ranges of durations of monocular phases, a binocular phase and an “empty” interval. In children of the control group when switching from the simple alternation regime to the “empty” interval regime the maximal durations of monocular phases, which preserved the stereoeffect, decreased and when switching to the binocular phase regime they significantly increased. In children with strabismus linear images are simpler for stereoperception than random-dot images as well as in children of the control group (p < 0.001); stimuli creating the effect of the frontoparallel separation of details get perceived better than those creating the decline effect or the turning effect (p < 0.001); stimuli creating the effect of the vertical stripes decline get perceived better than those creating the effect of the horizontal stripes turning (p < 0.001). However, as opposed to the children of the control group, in children with strabismus the stereoeffect gets formed better under conditions of the peripheral localization of linear details than under conditions of the central one.Conclusion. Using computer programs with different regimes of alternating presentation of stereostimuli with certain characteristics allows to effectively evaluate individual capability of stereoperception which is necessary for the personalized approach to the selection of visual stimuli and stimuli presentation regimes in functional treatment of patients with non-paralytic strabismus.

Results of Using Alternating Presentation of Stereostimuli in Children with Functional Scotoma in Non-Paralytic Strabismus

The work is devoted to one of the actual problems of modern strabismology — the study of the ability to stereo perception in children with non-paralytic strabismus.Purpose: to study the capability to stereovision with alternating presentation of stereostimuli in children with functional scotoma in non-paralytic strabismus.Patients and methods. 113 children with functional scotoma (FS) in non-paralytic strabismus were observed. We used stereostimuli with different characteristics in the following regimes of presentation: 1) the regime of simple monocular alternating (alternate presentation of an image for the right eye and the left eye); 2) the regime having an “empty” interval (black background) between monocular phases; 3) the regime having a binocular phase (a binocular image containing details corresponding to the stimuli for the right eye and the left eye) between monocular phases.Results. It was found that in 23 (20,3 %) children, the ability to stereo perception was completely absent. All these children had stable total FS (monocular vision). In the remaining 90 children (with unstable or regional FS), the ability to stereo perception was shown with some stimuli in some modes of their alternating presentation. For stimuli with a central arrangement of linear parts, the stereo effect was possible when they were presented in an alternating mode with an “empty” interval lasting from 20 to 70 ms in combination with the duration of monocular phases from 30 to 90 ms. For stimuli with a peripheral arrangement of linear elements, 22.1 % of children were able to stereo perception not only in the “empty” interval mode, but also in the simple alternation mode. At the same time, the greatest number of children capable of stereo perception was detected when using the mode with an “empty” interval of 30–60 ms and a duration of monocular phases of 40–60 ms. With random-dot stimuli, none of the children in this group were capable of stereo perception.Conclusion. Our results suggest that even in patients with FS in non-paralytic strabismus, stereo perception is possible under the conditions of alternating presentation of stimuli with certain characteristics. In this case, the most likely appearance of a stereo effect with stimuli containing peripheral linear elements that create a stereo effect when presented in an alternating mode with an empty interval between monocular phases.

New opportunities for surgical treatment of paralytic strabismus in children

Purpose. To assess the clinical effectiveness of the developed surgical method for treating paralytic strabismus. Material and methods. The operation was performed on 32 patients with paralytic strabismus (32 eyes) aged 3 to 12 years. All patients had diplopia in the primary gaze position or in a small abduction. Convergent strabismus was diagnosed in 26 children (81%), divergent strabismus – in 6 patients (19%), in 34% of cases (11 people) strabismus was with a vertical component. Strabismus angle according to Hirshberg before surgery: horizontal deviation from 10 to 30°, vertical – from 5 to 15°. Results. On the 7–10th day after the operation, orthotropy and the appearance of mobility of the eyeball towards the affected muscle were achieved in all operated patients. In the long term (6–12 months) after surgery, 23 children (72%) fully recovered the mobility of the eyeball in 8 directions and formed stable binocular vision, and orthotropy remained. In 9 patients (28%), there was a limitation of the mobility of the eyeball to 5–7°. Conclusion. The proposed method for the surgical treatment of paralytic strabismus makes it possible to achieve in one stage the correction of the deviation angle and the improvement of mobility with the elimination of diplopia, avoids the appearance of postoperative vertical deviation and eliminates large deviation angles. Using the proposed method, it is possible to simultaneously correct both horizontal and vertical deviations. Key words: paralytic strabismus, deviation angle, horizontal deviation, vertical deviation.