The efficacy of biofeedback visual rehabilitation therapy in patients with infantile nystagmus syndrome: A retrospective study

Abstract

<jats:sec><jats:title>Objective:</jats:title><jats:p> To report fixation stability changes in patients with different forms of infantile nystagmus syndrome (INS), who have undergone a visual rehabilitation through biofeedback fixation training (BFT) with microperimetry (MP). </jats:p></jats:sec><jats:sec><jats:title>Design:</jats:title><jats:p> Retrospective study. </jats:p></jats:sec><jats:sec><jats:title>Methods:</jats:title><jats:p> Patients 6 to 12 years-old with INS who performed BFT with MP. Initially 10 once-weekly followed by eight twice-weekly sessions of BFT during a minimum of 6 months period were performed. Visual acuity (VA) and MP fixation stability indices were analyzed, including displacement from fixation point (P1, P2) and percentage of retinal loci used during fixation attempt (BCEA 63% and 95%). Statistical analysis was conducted at baseline (BL), 10 weeks (W10) and 6 months (M6). </jats:p></jats:sec><jats:sec><jats:title>Results:</jats:title><jats:p> Twelve patients (mean age 8.9 years.) with INS completed the whole training session. All patients showed significant improvement in the mean BCEA fixation area (deg<jats:sup>2</jats:sup>): For BCEA@95% BL was 78.0, 46.1 at W10, and 27.4 at M6 ( p-value = 0.004). For BCEA@63% BL was 27.3, 15.4 in W10, and 9.17 at M6 ( p = 0.01). The ANOVA test for the FS indices of P1 and P2, as well as for BCVA showed no significant difference when compared at the same intervals. </jats:p></jats:sec><jats:sec><jats:title>Conclusion:</jats:title><jats:p> Fixation stability (FS) indices of BCEAs (63% and 95%) improved at W10 and M6, while P1 and P2 showed significant improvement at W10 but not at M6, probably because BCEA involves a much larger area than P1 and P2. VA did not show significant improvement at any time point. </jats:p></jats:sec>

Fixation instability, astigmatism, and lack of stereopsis as factors impeding recovery of binocular balance in amblyopia following binocular therapy

“…Foveal fixation depends on a diversity of voluntary and involuntary eye movements and eccentric (extra-foveal) fixation is closely associated with long-term visual acuity decrease after amblyopic treatment 76 . It has been previously established that (1) poor fixation stability is associated with poor monocular and binocular functions in amblyopic patients 16 – 18 , 77 – 79 ; (2) the time needed for the recovery and stabilization of visual acuity may be shorter for patients with better fixational abilities of the amblyopic eye in occlusion therapy 56 – 58 ; and (3) fixation stability can be improved in childhood 80 and even in adult patients over the critical period of development 81 – 85 . This is the first report, to our knowledge, showing that the more similar the fixation stability between the eyes, the more likely a patient classified as stereoblind according to Titmus test is to develop a certain level of stereopsis as a result of binocular treatment, regardless of etiology or severity of amblyopia and, more importantly, regardless of age.…”

Post audio-visual biofeedback training visual functions and quality of life in paediatric idiopathic infantile nystagmus: A pilot study

“…15–19 The results obtained in previous studies found increasing of foveation time, visual acuity improvement and nystagmus intensity reduction during the sessions. The protocols were not reproductible clinically, exception for Ciuffreda, 18 who used a special device for simulating BT. No methodology was developed before to follow the long-term efficiency of the method or BT benefits for other visual functions and QoL in children with IINS.…”

“…[14][15][16][17] These devices display images of the fundus and fixation points on a screen in real time, which allows guidance and biofeedback; therefore, it may help to improve oculomotor control increasing awareness of abnormal eye movements in nystagmus patients. Laboratory studies and a recent retrospective analysis 18 suggested a positive BT effect in reducing the nystagmus amplitude and improving fixation stability. [19][20][21][22][23] We hypothesize in this study that BT could optimize the visual functions and functional vision in pediatric patients with IINS, as well as QoL, opening a new possibility for treatment of IINS cases.…”

A new method of amblyopia treatment in children with unstable central and eccentric fixation using biofeedback

“…R. C ap u to и соавт. [14] в 2020 г. п р о вел и л еч ен и е с п ом ощ ью М -Б О С у 1 2 п ац и ен тов в возрасте от 6 до 1 2 лет с и ди оп ати чески м н и с тагмом. В результате авторы указали на у м ен ьш ен и е п л о щ а ди B C E A в с р о к н аб л ю ден и я до 6 м ес, одн ако п олучен н ы е у лучш ен и я н е п о вл и ял и н а М К О З. M. D aib e rt-N id o и с о авт.…”

“…Итогом проведенно го лечения явилось значительное улучшение фиксации, т. е. уменьшение амплитуды нистагма. Тем не менее в некоторых работах не была установлена связь стабилизации фиксации с повышением МКОЗ [14].…”