Purpose: Following interventions against trachoma in Viet Nam, impact surveys conducted in 2003-2011 suggested that trachoma was no longer a public health problem. In 2014, we undertook surveillance surveys to estimate prevalence of trachomatous inflammation-follicular (TF) and trichiasis. Methods: A population-based prevalence survey was undertaken in 11 evaluation units (EUs) encompassing 24 districts, using Global Trachoma Mapping Project methods. A two-stage cluster sampling design was used in each EU, whereby 20 clusters and 60 children per cluster were sampled. Consenting eligible participants (children aged 1-9 years and adults aged ≥50 years) were examined for trachoma. Results: A total of 9391 households were surveyed, and 20,185 participants (98.8% of those enumerated) were examined for trachoma. EU-level TF prevalence in 1-9-year-olds ranged from 0% to 1.6%. In one cluster (in Hà Giang Province), the percentage of children with TF was 10.3%. The overall pattern of cluster-level percentages of children with TF, however, was consistent with an exponential distribution, which would be consistent with trachoma disappearing. Among people aged ≥50 years, prevalence of trichiasis by EU ranged from 0% to 0.75%; these estimates are equivalent to 0-0.13% in all ages. The prevalence of trichiasis unknown to the health system among people aged ≥50 years, by EU, ranged from 0% to 0.17%, which is equivalent to 0-0.03% in all ages. Conclusion: Findings suggest that trachoma is no longer a public health problem in any of the 11 EUs surveyed. However, given the high proportion of children with TF in one cluster in Hà Giang Province, further investigations will be undertaken.

Background Symptoms due to dry eye in the form of keratoconjunctivitis sicca (KCS) are often seen after cataract surgery. We investigated the influence of cataract surgery on tear film stability on the ocular surface. Material and Methods 60 eyes of 60 patients who underwent cataract surgery were included in a prospective study in 2017 at the Eye Hospital in Hanoi (Vietnam National Institute of Ophthalmology). The mean age of the patients was 65 ± 10 years. The phacoemulsification was performed under topical anaesthesia by a clear corneal incision and implantation of a foldable IOL. The parameters for the evaluation of the change of the tear film included subjective patient data using the Ocular Surface Disease Index questionnaire (OSDI), findings of the Schirmer I test, the tear break-up time (TBUT) as well as the tear meniscus height (TMH) measured noninvasively with the Keratograph 5M (Oculus). In addition, conjunctival and corneal changes were examined after vital staining with fluorescein for the cornea and rose bengal for the conjunctiva. Data were collected preoperatively, at 1 week, 1 month and 3 months postoperatively. According to DEWS, the disease is classified into 4 groups: mild, moderate, severe and very severe. Results One week after surgery, the total score according to OSDI was significantly increased with a total value of 14.4 ± 4.2 (p = 0.001). Schirmer I was 15.8 ± 4.3 mm preoperatively and decreased significantly in the first postoperative week (p = 0.001), before reaching the preoperative level again after three months. TBUT was 12.6 ± 1.5 s preoperatively, decreased significantly to 9.7 ± 1.5 s during the first postoperative week, and normalized to 12.4 ± 1.3 s by the end of the third month. The meniscus height was 0.245 ± 0.055 mm preoperatively, significantly lowered to 0.229 ± 0.057 mm in the first postoperative period and nearly normalised by the third postoperative month to 0.241 ± 0.051 mm. In the first postoperative week, the rate of mild KCS was observed in 30% of patients. At one month, this decreased to 10% and at three months was no longer demonstrable in any patient. Conclusion One of three patients experienced mild KCS after cataract surgery. The symptoms lasted up to three months. This should be taken into account preoperatively and appropriate therapy should be planned.

Although steady fixation is a key aspect of a proper visual function, it is only subjectively assessed in young and uncooperative children. In the present study, we characterize the development of fixational behavior throughout childhood in a large group of healthy children 5 months of age and up, recruited in five geographically diverse sites. In order to do it, we examined 802 healthy children from April 2019 to February 2020. Their oculomotor behavior was analyzed by means of an automated digital system, based on eye-tracking technology. Oculomotor outcomes were gaze stability, fixation stability and duration of fixations (for both long and short fixational tasks), and saccadic reaction time. Ninety-nine percent of all recruited children were successfully examined. Fixational and saccadic performance improved with age throughout childhood, with more pronounced changes during the first 2 years of life. Gaze and fixation tended to be more stable with age ( p < 0.001 for most the outcomes), and saccades tended to be faster. In a multivariate analysis, including age and ethnicity as independent variables and adjusting by data quality, age was related with most fixational outcomes. Our automated digital system and eye-tracking data allow us to quantitatively describe the development of oculomotor control during childhood, assess visual fixation and saccadic performance in children 5 months of age and up, and provide a normative reference of fixational outcomes for clinical practice.

BACKGROUND: Cataract is one of the reasons which causes impaired visual acuity (VA) of the eyes after penetrating keratoplasy (PK), which can be treated by cataract surgery after PK or triple procedure. Cataract surgery after PK has advantages that parameters of the eyes such as axial length, anterior chamber depth (ACD) as well as corneal curvature are stabilized after removing all sutures postoperatively, and intraocular lens (IOL) power can be calculated correctly. Therefore, postoperative VA will be improved significantly. In Vietnam, there have not been any study about cataract surgery after PK, therefore we conduct this research. AIM: To evaluate the outcomes of phacoemulsification cataract surgery following primary PK. METHODS: Non-randomized controlled intervention study. Ninteen eyes (19 patients) that underwent phacoemulsification plus IOL insertion after initial PK in Cornea department, Vietnam National Institute of Ophthalmology, from December 2013 to September 2014. RESULTS: All patients presented with reduced VA, including 17 eyes (89.9%) with VA ≤ 20/200, mean astigmatism was 7.9 ± 1.0 D. Clear corneal grafts in 16 eyes while corneal opacity was seen in 3 eyes. All eyes with cataract were diagnosed from grade 2. After cataract surgery, improved VA > 20/200 was achieved in 72.22% of cases. There was a markable reduce of postoperative astigmatism with 1,8 ± 0.8 D (p < 0.05). However, the immunologic graft reaction was presented in one eye, and two edematous corneas also reported after cataract surgery. After treatment, there was one cornea achieved its clarity. CONCLUSION: Phacoemulsification cataract surgery following initial PK showed good outcomes with improved postoperative VA, reduced astigmatism, and the ultimate graft survival rate was high.