Background: A variety of experimental animal models are used in basic ophthalmological research to elucidate physiological mechanisms of vision and disease pathogenesis. The choice of animal model is based on the measurability of specific parameters or structures, the applicability of clinical measurement technologies, and the similarity to human eye function. Studies of eye pathology usually compare optical parameters between a healthy and altered state, so accurate baseline assessments are critical, but few reports have comprehensively examined the normal anatomical structures and physiological functions in these models.
Methods: Three cynomolgus monkeys, six New Zealand rabbits, ten Sprague Dawley (SD) rats, and BALB/c mice were examined by fundus photography (FP), fundus fluorescein angiography (FFA), and optical coherence tomography (OCT).
Results: Most retinal structures of cynomolgus monkey were anatomically similar to the corresponding human structures as revealed by FP, FFA, and OCT. New Zealand rabbits have large eyeballs, but they have large optic disc and myelinated retinal nerve fibers in their retinas, and the growth pattern of retinal vessels were also different to the human retinas. Unlike monkeys and rabbits, the retinal vessels of SD rats and BALB/c mice were widely distributed and clear. The OCT performance of them were similar with human beings except the macular.
Conclusions: Monkey is a good model to study changes in retinal structure associated with fundus disease, rabbits are not suitable for studies on retinal vessel diseases and optic nerve diseases, and rats and mice are good models for retinal vascular diseases. These measures will help guide the choice of model and measurement technology and reduce the number of experimental animals required.

Background: A variety of experimental animal models are used in basic ophthalmological research to elucidate physiological mechanisms of vision and disease pathogenesis. The choice of animal model is based on the measurability of specific parameters or structures, the applicability of clinical measurement technologies, and the similarity to human eye function. Studies of eye pathology usually compare optical parameters between a healthy and altered state, so accurate baseline assessments are critical, but few reports have comprehensively examined the normal anatomical structures and physiological functions in these models.
Methods: Three cynomolgus monkeys, six New Zealand rabbits, ten Sprague Dawley (SD) rats, and BALB/c mice were examined by fundus photography (FP), fundus fluorescein angiography (FFA), and optical coherence tomography (OCT).
Results: Most retinal structures of cynomolgus monkey were anatomically similar to the corresponding human structures as revealed by FP, FFA, and OCT. New Zealand rabbits have large eyeballs, but they have large optic disc and myelinated retinal nerve fibers in their retinas, and the growth pattern of retinal vessels were also different to the human retinas. Unlike monkeys and rabbits, the retinal vessels of SD rats and BALB/c mice were widely distributed and clear. The OCT performance of them were similar with human beings except the macular.
Conclusions: Monkey is a good model to study changes in retinal structure associated with fundus disease, rabbits are not suitable for studies on retinal vessel diseases and optic nerve diseases, and rats and mice are good models for retinal vascular diseases. These measures will help guide the choice of model and measurement technology and reduce the number of experimental animals required.

Background: Patients with dacryocystitis should be treated for their infection by endoscopic dacryocystorhinostomy (EN-DCR) before any intraocular surgery. However, there is no unified standard for the specific time interval between the two surgeries. This study aimed to determine the appropriate interval for intraocular surgery in patients with previous EN-DCR for chronic dacryocystitis.

Methods: The medical files of all patients who underwent intraocular surgery after EN-DCR surgery in our hospital from 2016 to 2019 were reviewed. The EN-DCR data of patients undergoing intraocular surgery at different time intervals and the incidence of endophthalmitis after intraocular surgery were compared.

Results: A total of 116 patients (92 females and 24 males, mean age 64.06±7.78 years) underwent EN-DCR and intraocular surgery met the inclusion criteria. The interval between EN-DCR and intraocular surgery varied from 5–475 days. The number of patients undergoing cataract surgery after EN-DCR is the largest (75, 64.7%). All patients (100%) who had previously undergone EN-DCR did not develop endophthalmitis infection after intraocular surgery at a follow-up of 12 months.

Conclusions: For patients with dacryocystitis who have undergone EN-DCR surgery, there is no time limit when choosing the timing of intraocular surgery. For patients requiring intraocular surgery, operation can be arranged as soon as possible to solve their problems as long as the patients had patency on lacrimal passage irrigation and no secretions.

Background: Patients with dacryocystitis should be treated for their infection by endoscopic dacryocystorhinostomy (EN-DCR) before any intraocular surgery. However, there is no unified standard for the specific time interval between the two surgeries. This study aimed to determine the appropriate interval for intraocular surgery in patients with previous EN-DCR for chronic dacryocystitis.

Methods: The medical files of all patients who underwent intraocular surgery after EN-DCR surgery in our hospital from 2016 to 2019 were reviewed. The EN-DCR data of patients undergoing intraocular surgery at different time intervals and the incidence of endophthalmitis after intraocular surgery were compared.

Results: A total of 116 patients (92 females and 24 males, mean age 64.06±7.78 years) underwent EN-DCR and intraocular surgery met the inclusion criteria. The interval between EN-DCR and intraocular surgery varied from 5–475 days. The number of patients undergoing cataract surgery after EN-DCR is the largest (75, 64.7%). All patients (100%) who had previously undergone EN-DCR did not develop endophthalmitis infection after intraocular surgery at a follow-up of 12 months.

Conclusions: For patients with dacryocystitis who have undergone EN-DCR surgery, there is no time limit when choosing the timing of intraocular surgery. For patients requiring intraocular surgery, operation can be arranged as soon as possible to solve their problems as long as the patients had patency on lacrimal passage irrigation and no secretions.

Background: The “flipped classroom” is a learner-centered approach that centers on delivering videos,podcasts or slide-based material to learners prior to a lecture or class session. The class session is then dedicated to discussion, analysis, and problem-solving activities. The aim of this study was to investigate whether the flipped classroom could be adapted to medical (ophthalmology) students learning about ocular trauma and to assess the impact of the flipped classroom on those students’ performance and attitudes.
Methods: Questionnaires (using a 4-point scale) were distributed to 93 fifth-year medical students at Sun Yat-sen University, and the data showed that the majority of students preferred the flipped classroom approach to the traditional lecture method.
Results: The results of pre- and post-test scores were 14.35±3.404 and 20.37±4.356, which showed a significant improvement in students’ performance after the flipped classroom was introduced (P<0.05).
Conclusions: Student response to the flipped classroom strategy was largely positive, indicating that the strategy received a high level of approval in an ophthalmology clerkship course taken by medical students in China.

Background: The “flipped classroom” is a learner-centered approach that centers on delivering videos,podcasts or slide-based material to learners prior to a lecture or class session. The class session is then dedicated to discussion, analysis, and problem-solving activities. The aim of this study was to investigate whether the flipped classroom could be adapted to medical (ophthalmology) students learning about ocular trauma and to assess the impact of the flipped classroom on those students’ performance and attitudes.
Methods: Questionnaires (using a 4-point scale) were distributed to 93 fifth-year medical students at Sun Yat-sen University, and the data showed that the majority of students preferred the flipped classroom approach to the traditional lecture method.
Results: The results of pre- and post-test scores were 14.35±3.404 and 20.37±4.356, which showed a significant improvement in students’ performance after the flipped classroom was introduced (P<0.05).
Conclusions: Student response to the flipped classroom strategy was largely positive, indicating that the strategy received a high level of approval in an ophthalmology clerkship course taken by medical students in China.

Backgrounds: To assess changes in anterior segment biometry during accommodation using a swept source anterior segment optical coherence tomography (SS-OCT).

Methods: One hundred-forty participants were consecutively recruited in the current study. Each participant underwent SS-OCT scanning at 0 and -3 diopter (D) accommodative stress after refractive compensation, and ocular parameters including anterior chamber depth (ACD), anterior and posterior lens curvature, lens thickness (LT) and lens diameter were recorded. Anterior segment length (ASL) was defined as ACD plus LT. Lens central point (LCP) was defined as ACD plus half of the LT. The accommodative response was calculated as changes in total optical power during accommodation.

Results: Compared to non-accommodative status, ACD (2.952±0.402 vs. 2.904±0.382 mm, P<0.001), anterior (10.771±1.801 vs. 10.086±1.571 mm, P<0.001) and posterior lens curvature (5.894±0.435 vs. 5.767±0.420 mm, P<0.001), lens diameter (9.829±0.338 vs. 9.695±0.358 mm, P<0.001) and LCP (4.925±0.274 vs. 4.900±0.259 mm, P=0.010) tended to decreased and LT thickened (9.829±0.338 vs. 9.695±0.358 mm, P<0.001), while ASL (6.903±0.279 vs. 6.898±0.268 mm, P=0.568) did not change significantly during accommodation. Younger age (β=0.029, 95% CI: 0.020 to 0.038, P<0.001) and larger anterior lens curvature (β= -0.071, 95% CI: -0.138 to -0.003, P=0.040) were associated with accommodation induced greater steeping amplitude of anterior lens curvature. The optical eye power at 0 and -3 D accommodative stress was 62.486±2.284 and 63.274±2.290 D, respectively (P<0.001). Age was an independent factor of accommodative response (β= -0.027, 95% CI: -0.038 to -0.016, P<0.001).

Conclusions: During -3 D accommodative stress, the anterior and posterior lens curvature steepened, followed by thickened LT, fronted LCP and shallowed ACD. The accommodative response of -3 D stimulus is age-dependent.

Backgrounds: To assess changes in anterior segment biometry during accommodation using a swept source anterior segment optical coherence tomography (SS-OCT).

Methods: One hundred-forty participants were consecutively recruited in the current study. Each participant underwent SS-OCT scanning at 0 and -3 diopter (D) accommodative stress after refractive compensation, and ocular parameters including anterior chamber depth (ACD), anterior and posterior lens curvature, lens thickness (LT) and lens diameter were recorded. Anterior segment length (ASL) was defined as ACD plus LT. Lens central point (LCP) was defined as ACD plus half of the LT. The accommodative response was calculated as changes in total optical power during accommodation.

Results: Compared to non-accommodative status, ACD (2.952±0.402 vs. 2.904±0.382 mm, P<0.001), anterior (10.771±1.801 vs. 10.086±1.571 mm, P<0.001) and posterior lens curvature (5.894±0.435 vs. 5.767±0.420 mm, P<0.001), lens diameter (9.829±0.338 vs. 9.695±0.358 mm, P<0.001) and LCP (4.925±0.274 vs. 4.900±0.259 mm, P=0.010) tended to decreased and LT thickened (9.829±0.338 vs. 9.695±0.358 mm, P<0.001), while ASL (6.903±0.279 vs. 6.898±0.268 mm, P=0.568) did not change significantly during accommodation. Younger age (β=0.029, 95% CI: 0.020 to 0.038, P<0.001) and larger anterior lens curvature (β= -0.071, 95% CI: -0.138 to -0.003, P=0.040) were associated with accommodation induced greater steeping amplitude of anterior lens curvature. The optical eye power at 0 and -3 D accommodative stress was 62.486±2.284 and 63.274±2.290 D, respectively (P<0.001). Age was an independent factor of accommodative response (β= -0.027, 95% CI: -0.038 to -0.016, P<0.001).

Conclusions: During -3 D accommodative stress, the anterior and posterior lens curvature steepened, followed by thickened LT, fronted LCP and shallowed ACD. The accommodative response of -3 D stimulus is age-dependent.

Background: Surgically induced astigmatism (SIA) and corneal high-order aberrations (HOAs) are the two main causes of poor visual quality after cataract surgery. Changes in the parameters of corneal HOAs after cataract surgery and their effects on and relationships with changes in corneal curvature have not yet been reported. This study aimed to explore changes in anterior, posterior and total corneal curvature, astigmatism and HOAs after microincision cataract surgery.

Methods: Sixty-one age-related cataract patients (61 eyes) were included in this prospective study. The total, anterior and posterior corneal astigmatism and corneal HOAs were analyzed by anterior segment optical coherence tomography (AS-OCT) and iTrace before, one day, one week and three months after 2.2 mm temporal microincision coaxial phacoemulsification to evaluate the changes in anterior, posterior and total corneal curvature, astigmatism and corneal HOAs.

Results: The mean J0 and J45 values of anterior, posterior and total corneal curvature obtained by AS-OCT showed no statistically significant difference between preoperatively and any postoperative follow-up. SIA occurred on the anterior, posterior and total corneal surfaces and showed no statistically significant difference at any postoperative follow-up. No significant changes in 3rd-order oblique trefoil, vertical coma or 4th-order spherical aberrations were observed after surgery except for a significant increase in horizontal coma at postoperative day 1 (POD1).

Conclusions: There were no significant changes in corneal curvature after 2.2 mm temporal microincision coaxial phacoemulsification, and the corneal HOAs were not changed significantly except for the increase in horizontal coma at POD1, which may be one of the main reasons of poor visual quality at POD1 in some cataract patients who have good uncorrected or corrected distance vision.

Background: Surgically induced astigmatism (SIA) and corneal high-order aberrations (HOAs) are the two main causes of poor visual quality after cataract surgery. Changes in the parameters of corneal HOAs after cataract surgery and their effects on and relationships with changes in corneal curvature have not yet been reported. This study aimed to explore changes in anterior, posterior and total corneal curvature, astigmatism and HOAs after microincision cataract surgery.

Methods: Sixty-one age-related cataract patients (61 eyes) were included in this prospective study. The total, anterior and posterior corneal astigmatism and corneal HOAs were analyzed by anterior segment optical coherence tomography (AS-OCT) and iTrace before, one day, one week and three months after 2.2 mm temporal microincision coaxial phacoemulsification to evaluate the changes in anterior, posterior and total corneal curvature, astigmatism and corneal HOAs.

Results: The mean J0 and J45 values of anterior, posterior and total corneal curvature obtained by AS-OCT showed no statistically significant difference between preoperatively and any postoperative follow-up. SIA occurred on the anterior, posterior and total corneal surfaces and showed no statistically significant difference at any postoperative follow-up. No significant changes in 3rd-order oblique trefoil, vertical coma or 4th-order spherical aberrations were observed after surgery except for a significant increase in horizontal coma at postoperative day 1 (POD1).

Conclusions: There were no significant changes in corneal curvature after 2.2 mm temporal microincision coaxial phacoemulsification, and the corneal HOAs were not changed significantly except for the increase in horizontal coma at POD1, which may be one of the main reasons of poor visual quality at POD1 in some cataract patients who have good uncorrected or corrected distance vision.

Objective: Day surgery mode has sharply shortened the preoperative waiting time of patients. However, this mode also made rough interactions between patients with vision loss and nursing staff during the preoperative visit. Moreover, patients might experience negative mood. The aim of this study was to describe the preoperative experiences and identify related stressful factors among patients who were waiting for vitreo-retinal day surgery. Methods: An interpretive qualitative approach guided this study. Semi-structured, face-to-face, in-depth interviews were carried out with patients from August 2021 to October 2021. Inductive content analysis and research software were used to analyze the data. Results: Elven patients agreed to join the interviews. The ages ranged from 19- to 70- year-old. The waiting time before hospitalization ranged from 7 to 90 days. Three main categories emerged from patients’ complaints: day surgery procedures, worries about eye conditions and supports. Conclusion: The findings highlighted the importance of preoperative care services. It was suggested that accurate preoperative information and effective supports are beneficial for improving the quality of preoperative care service.

Objective: Day surgery mode has sharply shortened the preoperative waiting time of patients. However, this mode also made rough interactions between patients with vision loss and nursing staff during the preoperative visit. Moreover, patients might experience negative mood. The aim of this study was to describe the preoperative experiences and identify related stressful factors among patients who were waiting for vitreo-retinal day surgery. Methods: An interpretive qualitative approach guided this study. Semi-structured, face-to-face, in-depth interviews were carried out with patients from August 2021 to October 2021. Inductive content analysis and research software were used to analyze the data. Results: Elven patients agreed to join the interviews. The ages ranged from 19- to 70- year-old. The waiting time before hospitalization ranged from 7 to 90 days. Three main categories emerged from patients’ complaints: day surgery procedures, worries about eye conditions and supports. Conclusion: The findings highlighted the importance of preoperative care services. It was suggested that accurate preoperative information and effective supports are beneficial for improving the quality of preoperative care service.