The ocular surface (OS) microbiome is influenced by various factors and impacts on ocular health. Understanding its composition and dynamics is crucial for developing targeted interventions for ocular diseases. This study aims to identify host variables, including physiological, environmental, and lifestyle (PEL) factors, that influence the ocular microbiome composition and establish valid associations between the ocular microbiome and health outcomes. The 16S rRNA gene sequencing was performed on OS samples collected from 135 healthy individuals using eSwab. DNA was extracted, libraries prepared, and PCR products purified and analyzed. PEL confounding factors were identified, and a cross-validation strategy using various bioinformatics methods including Machine learning was used to identify features that classify microbial profiles. Nationality, allergy, sport practice, and eyeglasses usage are significant PEL confounding factors influencing the eye microbiome. Alpha-diversity analysis revealed significant differences between Spanish and Italian subjects (p-value < 0.001), with a median Shannon index of 1.05 for Spanish subjects and 0.59 for Italian subjects. Additionally, 8 microbial genera were significantly associated with eyeglass usage. Beta-diversity analysis indicated significant differences in microbial community composition based on nationality, age, sport, and eyeglasses usage. Differential abundance analysis identified several microbial genera associated with these PEL factors. The Support Vector Machine (SVM) model for Nationality achieved an accuracy of 100%, with an AUC-ROC score of 1.0, indicating excellent performance in classifying microbial profiles. This study underscores the importance of considering PEL factors when studying the ocular microbiome. Our findings highlight the complex interplay between environmental, lifestyle, and demographic factors in shaping the OS microbiome. Future research should further explore these interactions to develop personalized approaches for managing ocular health.

Background and Objectives: To evaluate anterior capsule opening (ACO) contraction and late intraocular lens (IOL) dislocation after cataract surgery in patients with weak or partially absent zonular support and assess methods of reducing these complications. Materials and Methods: For this prospective study, we enlisted cataract surgery patients in our hospital with preoperative diagnoses of weak zonules. All patients received phacoemulsification surgery with implantation of a hydrophobic acrylic IOL and capsular tension ring (CTR). ACO reductions were measured for six months after enrolment. Data on late IOL dislocations were collected five years after enrolment of the last patient. Results: Fifty-three patients were enrolled from 2011 to 2015. Over the six-month active follow-up period, ACO area reduction was 23% in patients receiving CTRs of 11 mm diameter and 8% for patients with CTRs of 12 mm, with an overall mean of 15% reduction. Five years after the last patient was enrolled, seven patients (13%) had experienced late IOL-CTR-capsular bag dislocation. For these patients, the mean ACO reduction in the first six months of follow-up was 33%, including for those who had received neodymium-doped yttrium aluminum garnet (Nd: YAG) anterior capsulotomies. Conclusion: Use of hydrophobic acrylic lenses and CTR reduces ACO contraction, with rates comparable to those after cataract surgery without ocular comorbidity. Our patients experienced a relatively high rate of late IOL-CTR-capsular bag dislocation. However, dislocated complexes were easily repositioned and few patients required IOL exchange. Frequent visits are warranted to promptly detect late complications of cataract surgery in patients with weak zonular support.

This study sought to evaluate anterior capsulorhexis opening (ACO) reductions after surgery for a subluxated lens. Significant reduction of an ACO supports direct zonular involvement (capsular factors excluded by use of capsular tension rings [CTRs] and modern intraocular lens [IOLs]), and these findings question the long-term efficacy of subluxated lens surgery by means of cataract surgery. A small ACO due to lens mobility, non-enlargement of the ACO, and no lens epithelial cell washing due to an additional risk of further zonular damage were left as additional features to evaluate the possible outcomes of this simplified but still complicated surgery. Data from 30 patients were used in the final analysis of this prospective study. Phacoemulsifications of subluxated lenses were performed in all patients, and iris/capsule hooks and CTRs or Cionni rings were used as stabilisers of the lens. Photography of the anterior parts (performed at 1 day, 1 week, 1 month, 3 months and 6 months after surgery) was used to evaluate the anterior capsulorhexis openings. Small initial anterior capsulorhexis openings (13.54mm2) were achieved, and the area reduction at 6 months was 16.70% (mean area at month 6: 11.28mm2, P<0.001). The reduction of the ACO area in the pseudoexfoliation (PEX) syndrome patients was 20% relative to the initial size (13.49mm2 vs. 10.92mm2, P<0.001). Two patients exhibited marked ACO reductions, and both were referred for anterior laser capsulotomy treatment. A weak or partially absent zonule does not markedly affect the reduction of the anterior capsule opening if appropriate surgical techniques, support materials and IOLs are used, even in the presence of a small initial capsulorhexis opening area. Therefore, a cataract surgery approach on the subluxated lens should be used. Ocular comorbidities, particularly PEX syndrome, play more significant roles in ACO reduction, and appropriate ACO size reducing inhibitors (e.g., anterior laser capsulotomy) or other types of surgery should be used.

A cataract surgery in both eyes was scheduled for an 81-year-old female patient. However, ophthalmic examination revealed marked iridodonesis, phacodonesis and pseudoexfoliative material on the surface of the lens in both eyes indicating weak zonules caused by pseudoexfoliation syndrome, which was more pronounced in the left eye. Cataract surgery was performed initially in the left eye by phacoemulsification. Additionally, iris hooks and capsular tension ring (CTR) were used to stabilize the capsular bag, and the haptic of the intraocular lens (IOL) was sutured to the iris at the end of the surgery. The same procedure except haptic suturing was performed in the right eye after 6 months. The left eye remained stable, whereas the right eye developed considerable anterior capsular contraction 2 months postoperatively. Neodymium-doped yttrium aluminum garnet (Nd:YAG) laser capsulotomy was performed to treat the condition. Moreover, 3 years after the initial surgery, late IOL-CTR-capsular-bag complex dislocation developed in the right eye, and reposition surgery was performed. Three days after IOL-CTR-capsular-bag complex reposition surgery, endophthalmitis developed; the eye responded well to 1 mg intravitreal vancomycin treatment. IOL in the right eye remained stable 3 years postoperatively.

The human diving reflex is an innate cardiorespiratory adjustment triggered during apnea that concurrently activates both sympathetic and parasympathetic branches of the autonomic nervous system to maintain physiological stability under stress. Although pupil dilation and constriction are antagonistically regulated by these branches, the effect of the diving reflex on pupil diameter oscillations, known as hippus, remains unexplored. Here, we compared hippus in healthy participants during breathing or apnea either with (Wet) or without (Dry) facial immersion in cold water. In both apneic conditions, hippus exhibited reduced power in the low-frequency band (< 0.25 Hz). Notably, during Wet apnea, we observed a reallocation of power towards higher frequencies (> 0.25 Hz) and increased entropy of fluctuations, indicating a shift in autonomic balance and greater signal complexity during the diving reflex. This pilot study highlights pupil dynamics as a sensitive and non-invasive probe of autonomic adjustments underlying the human diving reflex.