Hasil untuk "Ophthalmology"

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S2 Open Access 2023
Performance of an Artificial Intelligence Chatbot in Ophthalmic Knowledge Assessment.

Andrew Mihalache, M. Popovic, R. Muni

Importance ChatGPT is an artificial intelligence (AI) chatbot that has significant societal implications. Training curricula using AI are being developed in medicine, and the performance of chatbots in ophthalmology has not been characterized. Objective To assess the performance of ChatGPT in answering practice questions for board certification in ophthalmology. Design, Setting, and Participants This cross-sectional study used a consecutive sample of text-based multiple-choice questions provided by the OphthoQuestions practice question bank for board certification examination preparation. Of 166 available multiple-choice questions, 125 (75%) were text-based. Exposures ChatGPT answered questions from January 9 to 16, 2023, and on February 17, 2023. Main Outcomes and Measures Our primary outcome was the number of board certification examination practice questions that ChatGPT answered correctly. Our secondary outcomes were the proportion of questions for which ChatGPT provided additional explanations, the mean length of questions and responses provided by ChatGPT, the performance of ChatGPT in answering questions without multiple-choice options, and changes in performance over time. Results In January 2023, ChatGPT correctly answered 58 of 125 questions (46%). ChatGPT's performance was the best in the category general medicine (11/14; 79%) and poorest in retina and vitreous (0%). The proportion of questions for which ChatGPT provided additional explanations was similar between questions answered correctly and incorrectly (difference, 5.82%; 95% CI, -11.0% to 22.0%; χ21 = 0.45; P = .51). The mean length of questions was similar between questions answered correctly and incorrectly (difference, 21.4 characters; SE, 36.8; 95% CI, -51.4 to 94.3; t = 0.58; df = 123; P = .22). The mean length of responses was similar between questions answered correctly and incorrectly (difference, -80.0 characters; SE, 65.4; 95% CI, -209.5 to 49.5; t = -1.22; df = 123; P = .22). ChatGPT selected the same multiple-choice response as the most common answer provided by ophthalmology trainees on OphthoQuestions 44% of the time. In February 2023, ChatGPT provided a correct response to 73 of 125 multiple-choice questions (58%) and 42 of 78 stand-alone questions (54%) without multiple-choice options. Conclusions and Relevance ChatGPT answered approximately half of questions correctly in the OphthoQuestions free trial for ophthalmic board certification preparation. Medical professionals and trainees should appreciate the advances of AI in medicine while acknowledging that ChatGPT as used in this investigation did not answer sufficient multiple-choice questions correctly for it to provide substantial assistance in preparing for board certification at this time.

264 sitasi en Medicine
DOAJ Open Access 2025
The Application of Traditional Chinese Medicine-Derived Formulations in Cancer Immunotherapy: A Review

Li Y, Li C, Fan J et al.

Yanyun Li,1 Changying Li,2 Junzi Fan,3 Yutong Liu,1 Yincong Xu,4 Guowei Pang1 1School of Acupuncture and Tuina, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, People’s Republic of China; 2School of Ophthalmology and optometry, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, People’s Republic of China; 3School of Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, People’s Republic of China; 4College of Traditional Chinese Medicine, Shandong University of Traditional Chinese Medicine, Jinan, Shandong, People’s Republic of ChinaCorrespondence: Yincong Xu; Guowei Pang, Email onion521@sina.com; pgw@sdutcm.edu.cnBackground: Cancer immunotherapy is an advanced therapeutic approach that harnesses the body’s immune system to target and eliminate tumor cells. Traditional Chinese medicine (TCM), with a history rooted in centuries of clinical practice, plays a crucial role in enhancing immune responses, alleviating cancer-related symptoms, and reducing the risks of infections and complications in cancer patients.Methodology: This review systematically examines the current literature on TCM-based formulations in cancer immunotherapy. It explores the mechanisms by which TCM augments immune responses, particularly focusing on how these formulations influence both innate and adaptive immunity. Various TCM herbs and compounds, their active ingredients, and their application in cancer prevention and treatment were analyzed through an integrated review of preclinical studies, clinical trials, and molecular mechanistic investigations.Results: TCM formulations contribute to cancer therapy by modulating the body’s internal environment to improve immune defense. They enhance the immune system’s ability to detect and destroy cancer cells, promote apoptosis in tumor cells, inhibit tumor growth and metastasis, and augment the effectiveness of conventional cancer treatments. The review highlights specific TCM herbs and formulations that have demonstrated significant anti-cancer properties, including their ability to strengthen immune responses and provide synergistic effects with existing cancer therapies.Conclusion: TCM-derived formulations represent a promising addition to cancer immunotherapy. The mechanisms through which these formulations enhance anti-tumor immunity are multifaceted, involving modulation of immune cell activity, apoptosis induction, and suppression of tumor progression. As cancer immunotherapy evolves, the integration of TCM into conventional treatment regimens may offer enhanced therapeutic efficacy, reduced side effects, and improved overall outcomes for cancer patients. Further clinical research is needed to fully elucidate the therapeutic potential and safety of TCM-based immunotherapeutic strategies in cancer care.Keywords: traditional Chinese medicine, TCM, cancer, nanocarriers, immune ability, anti-tumor therapy, tumor microenvironment, drug delivery systems

Neoplasms. Tumors. Oncology. Including cancer and carcinogens
DOAJ Open Access 2024
Biocompatibility of light responsive materials prepared for accommodative intraocular lenses manufacturing

Chen-Zi Liu, Ming-Hao Sun, Wei Dai et al.

AIM: To investigate the biocompatibility and bacterial adhesion properties of light responsive materials (LRM) and analyze the feasibility and biosafety of employing LRM in the preparation of accommodative intraocular lenses (AIOLs). METHODS: Employing fundamental experimental research techniques, LRM with human lens epithelial cells (hLECs) and human retinal pigment epithelium cells (ARPE-19 cells) were co-cultured. Commercially available intraocular lenses (IOLs) were used as controls to perform cell counting kit-8 (CCK-8), cell staining under varying light intensities, cell adhesion and bacterial adhesion experiments. RESULTS: LRM exhibited a stronger inhibitory effect on the proliferation of ARPE19 cells than commercially available IOLs when co-cultured with the undiluted extract for 96h (P<0.05). Under other culturing conditions, the effects on the proliferation of hLECs and ARPE-19 cells were not significantly different between the two materials. Under the influence of light irradiation at intensities of 200 and 300 mW/cm2, LRM demonstrated a markedly higher inhibitory effect on the survival of hLECs compared to commercially available IOLs (P<0.0001). They also showed a stronger suppressive effect on the survival rate of ARPE-19 cells, with significant differences observed at 200 mW/cm2 (P<0.001) and extremely significant differences at 300 mW/cm2 (P<0.0001). Additionally, compared to commercially available IOLs, LRM had a higher number of cells adhering to their surface (P<0.05), as well as a significantly greater number of adherent bacterium (P<0.0001). CONCLUSION: LRM, characterized by their excellent non-contact tunable deformability and low cytotoxicity to ocular tissues, show considerable potential for use in the fabrication of AIOLs. These materials demonstrate strong cell adhesion; however, during photothermal conversion processes involving shape deformation under various light intensities, the resultant temperature rise may harm surrounding cells. These factors suggest that while the material plays a positive role in reducing the incidence of posterior capsule opacification (PCO), it also poses potential risks for retinal damage. Additionally, the strong bacterial adhesion of these materials indicates an increased risk of endophthalmitis.

DOAJ Open Access 2024
M2 microglia-derived exosome-loaded electroconductive hydrogel for enhancing neurological recovery after spinal cord injury

Pengfei Guan, Lei Fan, Zhaobo Zhu et al.

Abstract Electroconductive hydrogels offer a promising avenue for enhancing the repair efficacy of spinal cord injuries (SCI) by restoring disrupted electrical signals along the spinal cord’s conduction pathway. Nonetheless, the application of hydrogels composed of diverse electroconductive materials has demonstrated limited capacity to mitigate the post-SCI inflammatory response. Recent research has indicated that the transplantation of M2 microglia effectively fosters SCI recovery by attenuating the excessive inflammatory response. Exosomes (Exos), small vesicles discharged by cells carrying similar biological functions to their originating cells, present a compelling alternative to cellular transplantation. This investigation endeavors to exploit M2 microglia-derived exosomes (M2-Exos) successfully isolated and reversibly bonded to electroconductive hydrogels through hydrogen bonding for synergistic promotion of SCI repair to synergistically enhance SCI repair. In vitro experiments substantiated the significant capacity of M2-Exos-laden electroconductive hydrogels to stimulate the growth of neural stem cells and axons in the dorsal root ganglion and modulate microglial M2 polarization. Furthermore, M2-Exos demonstrated a remarkable ability to mitigate the initial inflammatory reaction within the injury site. When combined with the electroconductive hydrogel, M2-Exos worked synergistically to expedite neuronal and axonal regeneration, substantially enhancing the functional recovery of rats afflicted with SCI. These findings underscore the potential of M2-Exos as a valuable reparative factor, amplifying the efficacy of electroconductive hydrogels in their capacity to foster SCI rehabilitation.

Biotechnology, Medical technology
DOAJ Open Access 2024
Compliance with the 2016 WHO’s antenatal care recommendation and its determinants among women in Sub-Saharan Africa: a multilevel-analysis of population survey data

Kusse Urmale Mare, Kebede Gemeda Sabo, Yordanos Sisay Asgedom et al.

Abstract Background Despite the positive impact of adhering to the new antenatal care model on pregnancy outcomes and maternal health service uptake, women in resource-limited settings exhibit low levels of compliance with this recommendation. Previous studies on women’s adherence to the new antenatal care recommendation have been limited to individual countries, with no evidence available at Sub-Saharan Africa (SSA) level. Therefore, this study sought to investigate compliance with the 2016 WHO’s recommendation of at least eight antenatal care contacts among women in SSA countries and identify its determinants. Methods The study utilized a weighted sample of 101,983 women who had received antenatal care during their index pregnancy, drawn from recent DHS data of sixteen SSA countries. A multilevel mixed-effect analysis was conducted to identify factors that influence compliance with new antenatal care recommendations. Model comparison was performed using deviance and log-likelihood values, and statistical significance was determined at a P-value of less than 0.05. Results The level of compliance with the recommended antenatal care contacts among women in SSA was 9.9% (95% CI: 9.7-10.1%), with the highest rate in Sierra Leone (26.1%) and lowest in Rwanda (< 1%). A multivariable logistic regression analysis showed that age, education, employment status, household wealth, healthcare decisions, the timing of antenatal contacts, consumption of nutritional supplements, residence, community-level women illiteracy, and media exposure were the significant determinants of compliance. Conclusion Only one in ten pregnant women in SSA countries had attended the recommended number of antenatal contacts, with Sierra Leone having the highest compliance rate and Rwanda and Senegal having the lowest. Therefore, policymakers should focus on improving access to education, especially for women and their partners, and providing exempted services for pregnant women from low-income households. Interventions that target communities with low levels of literacy and media exposure could also be effective in improving the uptake of the services.

Public aspects of medicine
DOAJ Open Access 2022
Predictive factors of the accelerated transepithelial corneal cross-linking outcomes in keratoconus

Mi Tian, Weijun Jian, Xiaoyu Zhang et al.

Abstract Background This study aimed to evaluate the clinical outcomes and assess preoperative characteristics that may predict outcomes in keratoconus 1 year after accelerated transepithelial corneal cross-linking (ATE-CXL). Methods This prospective study included 93 eyes of 84 consecutive keratoconus patients with 1-year follow-up after ATE-CXL. Preoperative characteristics included corneal astigmatism, anterior chamber depth, anterior chamber volume, radius of curvature, posterior elevation, central corneal thickness (CCT), thinnest corneal thickness, steepest meridian keratometry, flattest meridian keratometry, and the maximum keratometry (Kmax). Data were obtained preoperatively and at 1, 3, 6, and 12 months postoperatively. The patient eyes were grouped into 3 subgroups according to CCT and Kmax values to observe the changes of keratoconus progression. Results All patients were successfully operated without complications at any follow-up time point. Mean changes of Kmax from baseline at 6 and 12 months were − 0.60 ± 2.21 D (P = 0.011) and − 0.36 ± 1.58 D (P = 0.030), respectively. Eyes with a thinner CCT and higher Kmax values exhibited a tendency for topographic flattening of ≥1.0 D (P = 0.003; P = 0.003). In the subgroup comparison, the Kmax values decreased significantly at 6 and 12 months after ATE-CXL in the group with CCT ≤ 450 μm (P = 0.018 and P = 0.045); the Kmax values of the group with Kmax > 65.0 D decreased significantly at 6 months postoperatively (P = 0.025). Conclusion ATE-CXL is a safe and effective treatment for keratoconus patients. Patients with thinner CCT and higher Kmax values are more likely to benefit from ATE-CXL.

DOAJ Open Access 2022
Comparison of Indocyanine Green Angiography and Swept-Source Wide-Field Optical Coherence Tomography Angiography in Posterior Uveitis

Meng Tian, Meng Tian, Meng Tian et al.

PurposeTo compare indocyanine green angiography (ICGA) and swept-source wide-field optical coherence tomography angiography (SS-OCTA) for the assessment of patients with posterior uveitis.MethodSS-OCTA montage images of 5 x 12 x 12 mm or 2 x 15 x 9 mm, covering ~70–90 degree of the retina of consecutive patients with posterior uveitis were acquired. The choriocapillaries and choroidal slabs were compared to findings on ICGA.ResultsSixty-eight eyes of 41 patients were included (mean age 47.2 ± 20.4 years; 58.5% female). In 23 (34%) lesions were visible on OCTA, but not discernable on ICGA. In turn, out of the 45 eyes with clearly discernable lesions on ICGA, 22 (49%) and 21 (47%) eyes showed no corresponding areas of flow deficit on OCTA in the CC and choroidal slab, respectively. Lesion size strongly correlated among ICGA and OCTA choriocapillaries- (CC) (r = 0.99, p ≤ 0.0001) and choroidal slabs (r = 0.99, p ≤ 0.0001), respectively. The mean lesion size on the late frames of ICGA (8.45 ± 5.47 mm2) was larger compared to the lesion size on OCTA CC scan (7.98 ± 5.47 mm2, p ≤ 0.0001) and choroidal scan (7.69 ± 5.10 mm2, p = 0.002), respectively. The lesion size on OCTA CC scan was significantly larger than on the OCTA choroidal scan (p ≤ 0.0001).ConclusionSS-wide field OCTA may be a promising tool to assess posterior uveitis patients and may replace ICGA to a certain extent in the future.

Medicine (General)
DOAJ Open Access 2021
Assessing the Clinical Utility of Point of Care HbA1c in the Ophthalmology Outpatient Setting

Mamtora S, Maghsoudlou P, Hasan H et al.

Sunil Mamtora, 1 Panayiotis Maghsoudlou, 1, 2 Hani Hasan, 1 Wenrui Zhang, 3 Mohamed El-Ashry 1 1Department of Ophthalmology, Great Western Hospital, Swindon SN3 6BB, UK; 2Department of Developmental Biology, University College London, London WC1E 6BT, UK; 3Department of Ophthalmology, Queen Elizabeth University Hospital, Glasgow G51 4TF, UKCorrespondence: Panayiotis MaghsoudlouUniversity College London, London, UKTel +44 020 7242 9789Fax +44 020 7905 2000Email p.maghsoudlou@ucl.ac.ukBackground/Aims: Effective management of diabetic retinopathy requires multidisciplinary input. We aimed to evaluate the impact of point of care (POC) HbA1c testing as a tool to identify patients most in need of specialist diabetologist input and assess the accuracy and determinants of patients&rsquo; insight into their glycaemic and blood pressure control.Methods: Forty-nine patients with diabetic retinopathy were recruited from the eye clinic at Great Western Hospital. Patients completed a questionnaire and POC HbA1c and blood pressure values were measured. Statistical analysis was completed with SPSS v23.Results: Mean age was 64.4 years, median interval since the last formal HbA1c reading was 10.2 months and the mean POC HbA1c was 64.1 mmol/mol. HbA1c significantly correlated with the degree of retinopathy. Of the patients, 81.6% had POC readings above the levels recommended by the National Institute for Health and Care Excellence, with only 16.3% having insight into this. Insight to HbA1c levels was predicted by age but not by duration of disease. Fourteen patients (33.3%) identified with high HbA1c readings were referred to secondary diabetic services and 88.8% of patients felt that the test was useful and likely to improve their diabetic control.Conclusion: The majority of patients had poor insight into their diabetes control, with sub-optimal treatment and follow-up. Poor insight is high in younger patients, suggesting that POC HbA1c testing is particularly important in educating younger patients who may be Type 1 diabetics with more severe disease. POC HbA1c represents a cost-effective, reproducible and clinically significant tool for the management of diabetes in an outpatient ophthalmology setting, allowing the rapid recognition of high-risk patients and appropriate referral to secondary diabetic services.Keywords: diabetic retinopathy, glycemic control, point of care testing, HbA1c

Ophthalmology
DOAJ Open Access 2020
Indocyanine green angiographic findings in seven eyes with vasoproliferative retinal tumor

Saya Matsuura, Tomoka Ishida, Miho Tobe et al.

Purpose: Vasoproliferative tumors (VPTs) are rare benign tumors, and detailed indocyanine green angiographic (ICGA) findings in eyes with VPTs have not been reported. We present the characteristic ICGA findings in seven eyes with a VPT. Observations: We present the fluorescein angiographic (FA) and ICGA findings of seven consecutive patients who were diagnosed with primary VPT from April 2013 to March 2015 in the Oncology Service of the Department of Ophthalmology, Tokyo Medical and Dental University. We reviewed the demographics of the seven patients with VPTs. Abnormal vessels within the tumor were observed in three cases with active tumors. These vessels were hypofluorescent in the ICGA images in the scar phase. On the other hand, three cases in which the exudation remained from the initial visit to the last examination had abnormal vessels in the ICGA images. The remaining case had one straight vessel in the tumor from the initial to the last examination in the scar phase. FA in the active phase changed from hyperfluorescent leakage to staining in one eye, and the remaining six eyes continued to show hyperfluorescent leakage throughout the examination period. Conclusions: The leakage of fluorescein continued from the initial to the final examination even after the activity of the tumor had decreased. In the active phase, ICGA showed abnormal vessels with or without leakage, and the tumors at the scar phase show a hypofluorescent lesion. Importance: ICGA supported the ophthalmoscopic findings, and can be used as a diagnostic aid to confirm a regression of the VPTs.

DOAJ Open Access 2020
Influence of virtual reality on visual parameters: immersive versus non-immersive mode

Hyeon Jeong Yoon, Jonghwa Kim, Sang Woo Park et al.

Abstract Background To investigate the differences in refraction, accommodative factors, visual parameters, and subjective symptoms after using two types of virtual reality (VR) content with different depths of perception. Methods Twenty-three volunteers, who played VR games in two modes (immersive and non-immersive) for 30 min, were enrolled. Visual parameters were examined before and after using VR. Accommodative factors were measured using static and dynamic methods. Subjective symptoms were assessed using a questionnaire. Differences according to VR content were compared, and correlations between each visual parameter were analyzed. Results There were no changes in refraction or accommodative factors after use of the VR. However, there was a significant increase in the near point of accommodation (NPA), the near point of convergence (NPC), and subjective symptom scores after using the immersive mode. Correlation analysis revealed a positive correlation between baseline values of near exophoria and mean accommodative lag of the dominant eye, and also revealed a negative correlation between NPA and mean accommodative lag in the non-dominant eye. Conclusions The use of VR for 30 min increased NPA and NPC, especially after the immersive mode was used. In addition, higher exophoria and smaller NPA is associated with increased accommodative lag after using VR.

DOAJ Open Access 2019
How to improve Iranians’ vision health: on the national policy of preventing Iranians’ blindness

Behzad Damari, Alireza Mahdavi, Maryam Hajian

AIM: To review vision health situation of Iranian community, analyze its determinants, and discuss the adopted improvement strategies by the Iran Ministry of Health and Medical Education (MOHME). METHODS: This was a rapid situation analysis with a qualitative approach in three parts of recognition, orientation and implementation. The data were gathered via review of upstream documents, national and international experiences, and experts and stakeholders’ opinions. RESULTS: Eradicating trachoma, increasing human resources, increasing educational and research centers and promotion of ophthalmic technologies were important achievements in the field of vision health in Iran. Through these achievements, it seemed that the pattern of causes of blindness and low vision was similar to that of the developed countries. However, the review of Iranians’ vision health indicators showed that a considerable percent of the blindness and low vision was avoidable through a national program demanding 3 types of interventions in social determinants of health (SDH), community education, and increasing the access to health care services by integrating the necessary services in primary health care system. CONCLUSION: Managing the issue requires attentions from a national committee for preventing blindness with participation of all stakeholders, implementing a national survey on vision health, preparation of the primary level health centers including employment and education of community health workers (Behvarzes), optometrists and general practitioners, fair distribution of specialized human resources and establishing at least one specialized center in each province for referring patients from the primary levels.

DOAJ Open Access 2019
Topical Application of Liriope platyphylla Extract Attenuates Dry Eye Syndrome Induced by Particulate Matter

Su Jeong Song, Soo-Wang Hyun, Tae Gu Lee et al.

Particulate matter (PM) is a type of air pollutant that poses a risk to human health. In the ocular system, PM causes or aggravates dry eye syndrome (DES) by damaging the corneal and conjunctival epithelia. Liriope platyphylla has been used traditionally as an expectorant, antitussive agent, and tonic in Korea. However, the effects of Liriope platyphylla extract (LPE) on PM-induced ocular damage have not been elucidated. In this study, we evaluated the in vivo protective effect of LPE against PM-induced DES in rats. Topical administration of LPE attenuated the PM-induced decrease in tear volume and reduced corneal epithelial irregularity and damage. LPE also protected against PM-induced disruption of the corneal mucin-4 layer and reduction in the conjunctival goblet cell density. These findings suggest that LPE has protective effects against PM-induced DES.

S2 Open Access 1985
Clinical Ophthalmology

W.M Lyle

Background: The European Glaucoma Society recommends that selective laser trabeculoplasty (SLT) be considered as a first-line treatment option for patients with mild or moderate primary open-angle glaucoma (POAG) or for those who

421 sitasi en Medicine
DOAJ Open Access 2018
Bilateral acute retinal necrosis associated with bilateral uveal effusion in an immunocompetent patient: A challenging association

S Bala Murugan, Girish Bharat Velis, Manavi D Sindal

Bilateral uveal effusion syndrome associated with bilateral acute retinal necrosis is a diagnostic and therapeutic challenge. A 52 year old man presented with bilateral angle closure with choroidal detachment. With restricted fundus view, parenteral steroid was started. During close follow up bilateral discrete areas of peripheral retinitis were noted. Parenteral steroids were promptly stopped and parenteral antivirals with oral steroids were continued. It showed healing response with nil recurrences till last follow up. Aggressive treatment of bilateral uveal effusion with parenteral steroids can cause progression of bilateral acute retinal necrosis leading to phthisis bulbi. However early diagnosis, prompt intervention and close follow up are the key elements to therapeutic success even during diagnostic surprises and avoid costly mistakes.

DOAJ Open Access 2016
Comparison of microbiology and visual outcomes of patients undergoing small-gauge and 20-gauge vitrectomy for endophthalmitis

Almeida DRP, Chin EK, Shah SS et al.

David RP Almeida,1 Eric K Chin,2,3 Shaival S Shah,3 Benjamin Bakall,3 Karen M Gehrs,3 H Culver Boldt,3 Stephen R Russell,3 James C Folk,3 Vinit B Mahajan3,41VitreoRetinal Surgery PA, Minneapolis, MN, 2Retina Consultants of Southern California, Riverside, CA, 3Vitreoretinal Service, Department of Ophthalmology and Visual Sciences, 4Omics Laboratory, University of Iowa, Iowa City, IA, USABackground: The role of pars plana vitrectomy (PPV) for endophthalmitis has evolved over recent decades but the literature is lacking on comparisons between small-gauge and 20-gauge vitrectomy.Objective: To evaluate evolving etiological and microbiological trends in patients undergoing vitrectomy for endophthalmitis and to compare culture-positive rates and visual outcomes between small-gauge (23- and 25-gauge) and 20-gauge instrumentation during vitrectomy for endophthalmitis.Methods: Ten-year retrospective comparative case series and prospective laboratory in vitro testing. Tertiary care academic referral center. Patients who underwent PPV for endophthalmitis between 2003 and 2013. Vitreous biopsies were obtained in all cases. The effect of vitrectomy gauge (20-, 23-, and 25-gauge) and vitreous cutting rate (1,500 and 5,000 cuts per minute) on the viability of bacterial culture was evaluated in an in vitro prospective laboratory investigation.Main outcome measures: Comparison of etiology, microbiology culture-positive rates, and visual outcomes between small-gauge and 20-gauge instrumentation in patients undergoing PPV for infectious endophthalmitis.Results: A total of 61 cases of vitrectomy for endophthalmitis were identified over a 10-year period; of these, 34 were treated with small-gauge (23- and 25-gauge) vitrectomy and 27 were treated with 20-gauge vitrectomy. In the small-gauge group, 12 cases (35.3%) yielded culture-positive results versus 20 cases (74.1%) with culture positivity in the 20-gauge cohort (P=0.002). The most common cause of endophthalmitis was cataract surgery and the most frequently identified organism was coagulase-negative Staphylococci in both groups. There was no significant difference in mean postoperative visual acuities between groups (P=0.33). Etiological trends indicate an increase in endophthalmitis due to intravitreal injection in the small-gauge group (n=9) compared to the 20-gauge group (n=3) (P=0.001). In vitro laboratory testing revealed no significant difference in rates of culture growth for different vitrectomy gauge sizes or vitreous cutting speeds.Conclusion and relevance: Small-gauge vitrectomy for endophthalmitis yields final visual outcomes comparable to 20-gauge instrumentation. A significant difference in culture-positive rates was observed between small-gauge and 20-gauge instrumentation for vitrectomy in endophthalmitis; however, laboratory testing indicates this is not related to either vitreous gauge size or cutter speed. Intravitreal injections are emerging as a common etiology of vitrectomy for endophthalmitis.Keywords: endophthalmitis, vitrectomy, vitreous biopsy

Ophthalmology
DOAJ Open Access 2016
Precision of anterior and posterior corneal curvature measurements taken with the Oculus Pentacam

Elizabeth Chetty

In the era of rapid advances in technology, new ophthalmic instruments are constantly influencing health sciences and necessitating investigations of the accuracy and precision of the new technology. The Oculus Pentacam (70700) has been available for some time now and numerous studies have investigated the precision of some of the parameters that the Pentacam is capable of measuring. Unfortunately some of these studies fall short in confusing the meaning of accuracy and precision and in not being able to analyse the data correctly or completely. The aim of this study was to investigate the precision of the anterior and posterior corneal curvature measurements taken with the Oculus Pentacam (70700) holistically with sound multivariate statistical methods. Twenty successive Pentacam measurements were taken over three different measuring sessions on one subject. Keratometric data for both the anterior and posterior corneal surfaces were analysed using multivariate statistics to determine the precision of the Oculus Pentacam. This instrument was found to have good precision both clinically and statistically for anterior corneal measurements but only good clinical precision for the posterior corneal surface. Key words: Oculus Pentacam; keratometric variation; corneal curvature; multivariate statistics

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