Evaluation and reconstruction of visual function based on virtual reality technology / 中华实验眼科杂志

Virtual reality (VR) is a computer simulation system that can create and let users experience three-dimensional virtual scenes, and can provide users with multi-sensory information.In recent years, with the rapid development of 5G, artificial intelligence, big data and cloud computing, the application of VR technology in the field of ophthalmology has ushered in new opportunities and challenges.In terms of visual function assessment such as visual acuity, accommodative function, stereoscopic vision, VR combined with infrared eye tracking, binocular dichoptic vision and human-computer interaction can fully control the content presented to user, and provide the possibility to achieve personalized and automated diagnosis, which can effectively reduce labor costs.In the diagnosis and treatment of strabismus and amblyopia, VR combined with the above technologies and environmental immersion, three-dimensional imaging can provide users with rich images, reducing the difficulty of eye position measurement in strabismus and inhibition quantification in amblyopia.VR improves the fun and compliance of strabismus training, amblyopia training and stereoscopic training by imitating training paradigms such as convergence insufficiency training and visual perception training.The combination of augmented reality technology and computer-generated visual enhancement, holographic imaging, three-dimensional audio prompts and adaptive optics can effectively compensate for the visual defects of people with low vision and improve their quality of life.In the field of myopia prevention and control, the pros and cons of VR are still controversial, but it still has potential application value.In this article, the application status of virtual (augmented) reality technology in the assessment and reconstruction of visual function were reviewed, and the challenges it may face were analyzed, with a view to promoting the combination of medicine and engineering in ophthalmology diagnosis and treatment.

Comparison of the efficacy in adolescents with myopic anisometropia corrected by spectacles versus orthokeratology / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM:To observe the near stereoscopic visual function of adolescents with different degrees of myopic anisometropia after being corrected by spectacles and orthokeratology.METHODS:In this prospective clinical research,220 patients aged 10-20 years old with myopic anisometropia were recruited between March 2017 and December 2018. All the patients were divided into four groups according to the difference of cycloplegic spherical equivalent refractive(SER)error between the two eyes: group of 76 cases without anisometropia(SER error difference less than 1.00D), group of 60 cases with mild anisometropia(SER error difference of 1.00-<1.75D), group of 51 cases with moderate anisometropia(SER error difference of 2.00-<2.75D), and group of 33 cases with severe anisometropia(SER error difference of 3.00D or more). With regards the different optical correction approaches for myopia, 88 cases were categorized into the orthokeratology group and 132 cases into the spectacle group, the stereoacuity values at 3mo after correction were compared between the orthokeratology group and the spectacle group to see whether statistically significant difference existed.RESULTS:In the group of spectacle correction, there was significant statistical difference existed between the four sub-groups for the near stereoscopic visual function(<i>P</i><0.001). In the group of orthokeratology correction, there was no statistical difference existed between the four sub-groups for the near stereoscopic visual function(<i>P</i>=0.765). In both non-anisometropia and mild anisometropia groups, there was no statistical difference between the orthokeratology correction and spectacle correction sub-groups for the near stereoacuity values(<i>P</i>=0.109,<i>P</i>=0.052). However, in the moderate and severe anisometropia groups, orthokeratology group had better near stereoscopic vision than spectacle group(<i>P</i><0.001).CONCLUSION: Adolescents with myopic anisometropia corrected by orthokeratology lens were better at near stereoscopic visual function than corrected by spectacles, especially in the moderate and severe anisometropia groups.

Research on the formation mechanism and measurement method of stereoscopic vision / 国际眼科杂志(Guoji Yanke Zazhi)

@#Stereopsis is to perceive vision depth through the subtle three-dimensional differences between two eyes, and it is closely related to human working and living. There are different visual cortices in the cerebral cortex, which are involved in the formation of stereo vision, and process different visual information received. Clinical evaluation of stereo vision is needed to guide clinical decision-making. Traditional assessment is mainly based on static stereoscopic acuity, while binocular disparity appears dynamically with time in daily life. Nowadays 3D technology has been used to evaluate stereo vision. This paper mainly reviews the development mechanism and measurement methods of stereoscopic vision.

Effect of visual perception learning combined with occlusion on anisometropic amblyopia / 国际眼科杂志(Guoji Yanke Zazhi)

@#AIM: To study the therapeutic effect of visual perception learning combined with occlusion on visual acuity and stereoscopic function in patients with anisometropic amblyopia, and to compare the differences in visual acuity and stereoscopic visual function enhancement.<p>METHODS: A total of 47 patients with monocular anisometropic amblyopia who were treated in our hospital from June 2016 to December 2017 were enrolled. The visual acuity learning system combined with occlusion for amblyopia treatment was used to observe the best corrected visual acuity of 47 patients before and after treatment, and the result of random point dynamic 2nd order rough stereoscopic view, random point dynamic 1st order stereoscopic view between fine and rough, random point static 0-order near, far fine stereoscopic view, and to compare the difference between visual acuity improvement and stereo vision improvement.<p>RESULTS: After treatment, the visual acuity improvement degree was significantly different from that of dynamic 2nd order rough stereoscopic vision of random points, dynamic 1st order fine stereoscopic vision of random points, static 0 order near and far fine stereoscopic vision of random points,and the degree of improvement is obviously inconsistent. The difference was statistically significant.<p>CONCLUSION: The degree of visual acuity in patients with anisometropic amblyopia is not synchronized with the improvement of stereopsis. The stereoscopic function of patients with basically curedvisual acuity is not basically normal. Therefore, the training and establishment of stereoscopic function in patients with anisometropic amblyopia should be concerned. The measurement of stereopsis may become a new classification method and treatment standard for amblyopia.

Effect of orthokeratology on stereopsis, accommodation parameters and ocular biological parameters in myopic patients / 国际眼科杂志(Guoji Yanke Zazhi)

AIM:To investigate the effect of orthokeratology on stereopsis, accommodation parameters and ocular biological parameters in myopic patients. METHODS: The clinical data of 65 patients (130 eyes) with myopia in our hospital from January 2016 to May 2017 were analyzed and they were divided into high myopia group,moderate myopia group and slight myopia group. The changes of stereopsis, accommodation parameters and ocular biological parameters were compared between the myopic patients before and after the operation. RESULTS: The difference of distant vision, stereo acuity, accommodation range and accommodation sensitivity between the three groups were statistically significant (P<0.05). The uncorrected visual acuity, the degree of spherical equivalent and the diopter of cylindrical power in the myopic eyes were significantly lower than those before treatment,and the difference was statistically significant (P<0.05). The intraocular pressure and central corneal thickness were not different compared with before treatment (P>0. 05). After treatment, the corneal curvature was lower and axial length were higher than those before treatment, the difference was statistically significant (P<0.05). CONCLUSION: Orthokeratology can obviously improve the distance and near vision and stereoscopic vision function of myopic patients,which may slow the increase of axis and reduce the corneal curvature.

Anatomia microcirúrgica das artérias infratentoriais: um estudo estereoscópico / Microsurgical anatomy of the infratentorial arteries: stereoscopic printing study

CONTEXTO: O espaço infratentorial do crânio é uma região que possui complexa rede de artérias que vascularizam o tecido cerebelar e o tronco encefálico. Sua complexa anatomia tridimensional deve ser profundamente entendida pelo neurocirurgião vascular e pelo radiologista intervencionista. OBJETIVO: Descrever as principais artérias do espaço infratentorial e seu trajeto, bem como sua relação com a topografia das estruturas neurais. MÉTODOS: Foram estudados 30 cérebros humanos, fixados em formalina e 6 cabeças de cadáveres dissecadas, utilizando-se microscópico cirúrgico com 3X a 40X de aumento. Os cérebros e todas as cabeças foram injetados com siloxanos polimerizados ou polisiloxanos (silicone) colorido. As dissecções anatômicas foram documentadas utilizando-se técnica para obtenção de imagens tridimensionais (3D), objetivando a produção de impressões estereoscópicas. RESULTADOS: São descritos o trajeto, segmentos e ramos das artérias basilar, cerebelar superior, cerebelar anteroinferior, cerebelar posteroinferior e vertebral. CONCLUSÃO: A anatomia das artérias infratentoriais é complexa e as imagens estereoscópicas apresentadas são um importante instrumento de documentação, pois permitem uma noção de profundidade da anatomia estudada.

BACKGROUND: The infratentorial space is a region with a complex network of arteries supplying the cerebellum and brainstem. Its complex three-dimensional anatomy must be thoroughly understood by the vascular neurosurgeon and the interventional radiologist. OBJECTIVE: To describe the main arteries of the infratentorial space and its trajectory and its relationship to the topography of the neural structures. METHODS: We studied 30 formalin-fixed human brains and we also dissected 6 cadaver heads, using a surgical microscope with 3X to 40X magnification. The brains and all heads were injected with colored silicone. The anatomical dissections were documented with a three-dimensional method, aiming to produce stereoscopic prints. RESULTS: The neurovascular relationships, segments and branches of the basilar artery, superior cerebellar, anteroinferior cerebellar, cerebellar and posteroinferior vertebral are described. CONCLUSION: The microsurgical anatomy of the infratentorial arteries is complex and the stereoscopic images presented are an important tool for documentation.

Anatomia microcirúrgica da artéria carótida externa: um estudo estereoscópico / Microsurgical anatomy of the external carotid artery: a stereoscopic study

CONTEXTO: O conhecimento das estruturas anatômicas da artéria carótida externa por meio do estudo estereoscópico pode determinar melhores resultados em microcirurgias da artéria carótida externa. OBJETIVO: Descrever as estruturas da artéria carótida externa sob a visão estereoscópica, identificando seus múltiplos aspectos. MÉTODOS: Doze regiões cervicais foram dissecadas, utilizando-se microscópico cirúrgico com 3 a 40x de aumento. As dissecções anatômicas foram documentadas utilizando-se a técnica para obtenção de imagens tridimensionais (3D), objetivando a produção de impressões estereoscópicas. RESULTADOS: O uso da técnica estereoscópica possibilitou a abordagem da circulação arterial extracraniana, sendo realizados estudos cirúrgicos do tipo combinado fossa posterior e fossa infratemporal, tornando as microcirurgias e os procedimentos neurocirúrgicos vasculares mais precisos. CONCLUSÃO: O uso das imagens obtidas pela técnica estereoscópica produziu um resultado mais assertivo em relação ao estudo da anatomia para a microcirurgia e procedimentos neurocirúrgicos, facilitando melhor aprendizado previamente à realização de procedimentos complexos em neurocirurgia.

BACKGROUND: The knowledge on the anatomical structures of the external carotid artery through the stereoscopic study may provide better results in microsurgical treatment of the external carotid artery. OBJECTIVE: To describe the structures of the external carotid artery under stereoscopic vision, identifying its multiple aspects. METHODS: Twelve cervical regions were dissected using a surgical microscope with 3 to 40x magnification. The anatomical dissections were documented using the technique to obtain three-dimensional images (3D), aiming at producing stereoscopic prints. RESULTS: The use of the stereoscopic technique enabled the stereoscopic approach to extracranial arterial circulation, and it was followed by a combined posterior fossa and infratemporal approach, making microvascular surgery and neurosurgical procedures more precise. CONCLUSION: The use of images obtained through the stereoscopic technique produced a more assertive result in relation to the anatomy study for microsurgical or neurosurgical procedures, facilitating a better learning before performing complex procedures in neurosurgery.

Application of Stereo-Imaging Technology to Medical Field / 대한의료정보학회지

OBJECTIVES: There has been continuous development in the area of stereoscopic medical imaging devices, and many stereoscopic imaging devices have been realized and applied in the medical field. In this article, we review past and current trends pertaining to the application stereo-imaging technologies in the medical field. METHODS: We describe the basic principles of stereo vision and visual issues related to it, including visual discomfort, binocular disparities, vergence-accommodation mismatch, and visual fatigue. We also present a brief history of medical applications of stereo-imaging techniques, examples of recently developed stereoscopic medical devices, and patent application trends as they pertain to stereo-imaging medical devices. RESULTS: Three-dimensional (3D) stereo-imaging technology can provide more realistic depth perception to the viewer than conventional two-dimensional imaging technology. Therefore, it allows for a more accurate understanding and analysis of the morphology of an object. Based on these advantages, the significance of stereoscopic imaging in the medical field increases in accordance with the increase in the number of laparoscopic surgeries, and stereo-imaging technology plays a key role in the diagnoses of the detailed morphologies of small biological specimens. CONCLUSIONS: The application of 3D stereo-imaging technology to the medical field will help improve surgical accuracy, reduce operation times, and enhance patient safety. Therefore, it is important to develop more enhanced stereoscopic medical devices.

Clinical Value of Stereoscopic Three-dimensional Echocardiography in Assessment of Atrial Septal Defects:Feasibility and Efficiency / 华中科技大学学报（医学）（英德文版）

Stereoscopic three-dimensional echocardiography(S-3DE) is a novel displaying technology based on real-time 3-dimensional echocardiography (RT-3DE). Our study was to evaluate the feasibility and efficiency of S-3DE in the diagnosis of atrial septal defect (ASD) and its use in the guidance for transcatheter ASD occlusion. Twelve patients with secundum ASD underwent RT-3DE examination and 9 of the 12 were subjected to transcatheter closure of ASD. Stereoscopic vision was generated with a high-performance volume renderer with red-green stereoscopic glasses. S-3DE was compared with standard RT-3D display for the assessment of the shape,size,and the surrounding tissues of ASD and for the guidance of ASD occlusion. The appearance rate of coronary sinus and the mean formation time of the IVC,SVC were compared. Our results showed that S-3DE could measure the diameter of ASD accurately and there was no significant difference in the measurements between S-3DE and standard 3D display (2.89±0.73 cm vs 2.85±0.72 cm,P＞0.05;r=0.96,P＜0.05). The appearance of coronary sinus for S-3DE was higher as compared with the standard 3D display (93.3% vs 100%). The mean time of the IVC,SVC for S-3DE monitor was slightly shorter than that of the standard 3D display (11.0±3.8 s vs 10.3±3.6 s,P＞0.05). The mean completion time of interventional procedure was shortened with S-3DE display as compared with standard 3D display (17.3±3.1min vs 23.0±3.9 min,P＜0.05). Stereoscopic three-dimensional echocardiography could improve the visualization of three-dimensional echocardiography,facilitate the identification of the adjacent structures,decrease the time required for interventional manipulation. It may be a feasible,safe,and efficient tool for guiding transcatheter septal occlusion or the surgical interventions.

Effect of visual function on posterior capsule opacification before and after Nd:YAG laser posterior capsulotomy / 眼科

Objective To explore the influence of stereoscopic vision on the development of posterior capsule opacification (PCO) after intraocular lens implantation. The efficacy of Nd: YAG laser was studied. Design Case-controlled study. Participants 57 consecutive patients with POC(59 eyes with phacoemulsification and IOL implantation). Methods A prospective observational study was conducted comprising 57 patients (59 eyes) who had postoperative PCO. Neodymium: YAG (Nd: YAG) laser posterior capsulatomy was performed on all patients following a standardizes procedure. Preoperative and postoperative evaluation included LogMAR visual acuity, best-corrected visual acuity (BCVA), contrast sensitivity and stereoscopic vision. Main Outcome Measures LogMAR visual acuity, BCVA, contrast sensitivity and stereoscopic vision. Results The average LogMAR eyesight median of sick eye before laser treatment was (0.22?0.31) and the contrast sensitive degree of each frequency area was relatively lower than the opposite eye; After the treatment, there was evident improvement of the sick eye, and the LogMAR eyesight median of that was 0.00; The ratio of reaching the central spatial eyesight and the average sharpness degree both improve much than ahead of treatment. Those whose spatial eyesight sharpness don't get normal after the low best remedy eyesight. Irregular dipodic and previous eye disease. Conclusions LogMAR visual acuity, BCVA, contrast sensitivity and stereoscopic vision were damaged markedly with PCO. Our results indicate that Nd: YAG capsulotomy may affect the reconstruction of stereoscopic vision. Nd:YAG laser posterior capsulotomy is a valuable and clinically relevant method for clinical treatment of PCO.