Gut Dysbiosis and Blood-Brain Barrier Alteration in Hepatic Encephalopathy: From Gut to Brain.

A common neuropsychiatric complication of advanced liver disease, hepatic encephalopathy (HE), impacts the quality of life and length of hospital stays. There is new evidence that gut microbiota plays a significant role in brain development and cerebral homeostasis. Microbiota metabolites are providing a new avenue of therapeutic options for several neurological-related disorders. For instance, the gut microbiota composition and blood-brain barrier (BBB) integrity are altered in HE in a variety of clinical and experimental studies. Furthermore, probiotics, prebiotics, antibiotics, and fecal microbiota transplantation have been shown to positively affect BBB integrity in disease models that are potentially extendable to HE by targeting gut microbiota. However, the mechanisms that underlie microbiota dysbiosis and its effects on the BBB are still unclear in HE. To this end, the aim of this review was to summarize the clinical and experimental evidence of gut dysbiosis and BBB disruption in HE and a possible mechanism.

Interocular Axial Length Difference and Treatment Outcomes of Anisometropic Amblyopia.

Purpose: To evaluate the effect of interocular axial length (AL) difference on outcomes of treatment for anisometropic amblyopia in comparison with normal participants. Methods: In this historical cohort study, 83 patients with anisometropic amblyopia were divided into two age groups, 70 children (mean, 7.86 ± 1.56 and range, 5-15 years) and 13 adults (mean, 26.46 ± 10.87 and range, 16-45 years). The control group consisted of 43 non-amblyopic children and 17 non-amblyopic adults. Treatment outcomes after a period of one year were defined as successful or unsuccessful when posttreatment amblyopic corrected distance visual acuity (CDVA) was reported as ≤ 0.9 versus CDVA ≤ 0.8, respectively. AL was measured using a Lenstar LS900 (Haag-Streit AG, Switzerland). Results: Fifty-nine patients showed satisfactory treatment outcomes (55 children and 4 adults), while unsuccessful treatment outcomes were observed in 24 patients (15 children and 9 adults). The mean of amblyopia treatment duration was 1.24 ± 0.76 years. The mean of interocular AL difference in all patients, control, successful and unsuccessful treatment outcome groups were 0.49 ± 0.70mm (range, 0.00-3.89 mm), 0.12 ± 0.07 mm (range, 0.02-0.41), 0.33 ± 0.23 mm (range, 0.00-0.99 mm), and 1.81 ± 0.80 mm (range, 1.14-3.89 mm), respectively. In both age groups, the mean of interocular AL difference in patients with unsuccessful treatment outcomes was greater than those with successful treatment outcomes and that of the control group (P < 0.001). Conclusion: The results of this study suggest that the outcome of anisometropic amblyopia treatment may depend on the interocular AL difference.

The effect of different amblyopia treatment protocols on axial length of non-amblyopic eyes in anisohyperopic patients.

PURPOSE: To evaluate the effect of full-time and part-time occlusion therapy on axial length (AL) of non-amblyopic eyes in anisohyperopic patients. METHODS: Sixty-five patients who were treated for anisohyperopic amblyopia were recruited for this prospective cross-sectional study. Treatment was provided as patching of the non-amblyopic for 4 h or less (part-time occlusion therapy, n = 42), patching of the non-amblyopic for 8 h or more (full-time occlusion therapy, n = 13) and refractive correction (spectacles, non-patched group, n = 10). AL measurements were calculated by a Lenstar LS 900 at the last session of amblyopia therapy. RESULTS: The mean age of patients treated for anisohyperopic amblyopia was 4.90 ± 0.80 years, and the mean follow-up period was 1.50 ± 0.80 years. The mean of spherical equivalent in amblyopic and non-amblyopic eyes were +3.58 ± 2.26 and +1.84 ± 0.97 diopter (D) before treatment, and +3.21 ± 2.28 and +1.49 ± 0.99 D after treatment, respectively. The mean of spherical equivalent in non-amblyopic eyes before (F = 0.452, df = 2, P = 0.639) and after (F = 0.190, df = 2, P = 0.828) treatment did not have any significant difference between the three groups. The mean AL of amblyopic and non-amblyopic eyes were 22.11 ± 93.0 and 22.68 ± 1.07 mm, respectively. The mean AL of the non-amblyopic eye was significantly higher in the full-time occlusion therapy group when compared to the part-time patch and the non-patched groups (P < 0.001). The mean AL of amblyopic eyes showed no difference across the three treatment groups (P = 0.840). CONCLUSIONS: The results show that a longer AL in the non-amblyopic eye, but not the amblyopic eye, can be expected with longer daily hours of patching in anisohyperopic patients. Future studies are needed to evaluate the effect of patching on AL in children with anisohyperopic amblyopia.