Uncalibrated Positioning Method for Puncture Robots Based on Optical Navigation / 中国医疗器械杂志

Robotic puncture system has been widely used in modern minimally invasive surgery, which usually uses hand-eye calibration to calculate the spatial relationship between the robot and the optical tracking system. However, the hand-eye calibration process is time-consuming and sensitive to environmental changes, which makes it difficult to guarantee the puncture accuracy of the robot. This study proposes an uncalibrated positioning method for puncture robot based on optical navigation. The method divides the target path positioning into two stages, angle positioning and position positioning, and designs angle image features and position image features respectively. The corresponding image Jacobian matrix is constructed based on the image features and updated by online estimation with a cubature Kalman filter to drive the robot to perform target path localization. The target path positioning results show that the method is more accurate than the traditional hand-eye calibration method and saves significant preoperative preparation time by eliminating the need for calibration.

Pose Testing Method for Medical Service Robots Based on Vision System / 中国医疗器械杂志

Aiming at the medical service robot used in the indoor environment, this study proposes a method to test the pose accuracy of its working surface based on the binocular vision system. This method uses a binocular vision coordinate system to measure targets fixed on the working surface of the service robot, aligns the measurement system with the robot base coordinate system through the nonlinear least squares method, and integrates the multi-eye image data to achieve the accuracy test of the working surface. Finally, the vision test program was tested and verified on a mobile service robot model ABIR X8. According to the accuracy index given in GB/T 38124 Service Robot Performance Test Method, the test results of its pose accuracy were obtained.

Fréquence des amétropies aux cliniques universitaires du graben en République Démocratique du Congo

Introduction : Les amétropies sont des troubles de la vision dus à un fonctionnement défectueux du système optique formé par la succession la cornée, le cristallin et la rétine. Les vices de réfraction (myopie, hypermétropie, astigmatisme, presbytie) donnent des images floues sur la rétine. L'Organisation Mondiale de la Santé (OMS) estime à 153 millions le nombre des personnes souffrant de la déficience visuelle due à des vices de réfraction non corrigés. Le présent travail a pour objectif de déterminer la fréquence et le profil des patients avec amétropies aux Cliniques universitaires de Graben. Méthodes : Notre étude était du type descriptif transversale ayant couvert une période allant du 01 Janvier au 31 Décembre 2020. Notre échantillon a été exhaustif, c'est-à-dire il a été constitué de toute la population d'étude. Résultats : La fréquence des amétropies a été de 11,47%. L'astigmatisme était l'amétropie la plus représentée avec 47,86 %suivi de la myopie avec 38,90% et de l'hypermétropie avec 13,24%. La tranche d'âge la plus touchée est celle des adultes, âge (21-60 ans) avec 73,9% et la moins touchée est de 0-10 ans avec 0,8%. Le taux des déficiences visuelles a diminué après la correction optique et les cas de bonne vision sont passés de 81,1% à 99,4% de bonne acuité visuelle. Conclusion. Les amétropies constituent un réel problème de santé publique. De ce fait, nous encourageons le check up volontaire, comme les amétropies sont souvent méconnues et indolores, pourtant une cause non négligeable de déficience visuelle facilement évitable.

Introduction: : Ametropia are vision disorders due to damage to the visual system caused by a various abnormality in the cornea, lens and retina. The refractive errors (myopia, hyperopia, astigmatism, presbyopia) cause a very weak capacity for the eye retina to properly watch images. The World Health Organization (WHO) estimates that 153 million of people could be suffering from visual issues due to untreated refractive deficiencies. This study aimed to determine the frequency et profil of patients with ametropia. Methods: Our study was of a kind of crosssectional descriptive which covered a time interval from January 01 to December 31, 2020. Our sample was comprehensive and was based on several cases. Results: The frequency of ametropia was 11.47%. Astigmatism was the most prevalent ametropia with 47.86% followed by myopia with 38.90% and hyperopia with 13.24%.The most affected people are adults aged from 21 and 60 years with 73.9% and the least affected are children aged from 0 to 10 years with 0.8%.However, the rate of eyes abnormalities started decreasing after optical treatment and consequently the cases of eyes issues recoveries was about from 81.1% to 99.4% of sight improvement acuity. Conclusion: Ametropia is a real public health problem. As a result, we encourage voluntary check-ups, as ametropia is often unrecognized and painless, yet a significant cause of easily avoidable visual impairment.

A Fluorescence Diffusion Optical Tomography System Based on Lattice Boltzmann Forward Model / 中国医疗器械杂志

Fluorescence Diffuse Optical Tomography (FDOT) is significant for biomedical applications, such as medical diagnostics, drug research. The fluorescence probe distribution in biological tissues can be quantitatively and non-invasively obtained via FDOT, achieving targets positioning and detection. In order to reduce the cost of FDOT, this study designs a FDOT system based on Lattice Boltzmann forward model. The system is used to realize two functions of light propagation simulation and FDOT reconstruction, and is composed of a parameter module, an algorithm module, a result display module and a data interaction module. In order to verify the effectiveness of the platform, this study carries out the light propagation simulation experiment and the FDOT reconstruction experiment, respectively comparing the Monte Carlo (MC) light propagation simulation results and the real position of the light source to be reconstructed. Experiments show that the proposed FDOT system has good reliability and has a high promotion value.

Traços de uma sttética do silício / Rasgos de unaesttética del silicio / Traces of asiliccon aesthetics

Este artigo procura apresentar os conceitos de agenciamento e phylum maquínico, concebidos por Gilles Deleuze e Felix Guattari, para sublinhar o silício dentro do agenciamento contemporâneo homem-natureza. O silício (Si), matéria de destaque da microeletrônica, torna-se matéria expressiva de uma ética e de uma estética próprias. Com o objetivo de cartografar as forças que se colocam em ação em alguns agenciamentos homem-silício, busca criar uma imagem-pensamento tributária de uma estética do silício, que exprime um modo de existência. Neste trajeto, estão cartografadas algumas linhas de sustentação de uma sociedade de controle e outras linhas que agem em ruptura com a mesma. Com a arte, na idade da informatização planetária, vislumbram-se linhas orientadas a uma nova processualidade criativa e singularizante, capazes de promover mudanças nos posicionamentos do homem por uma vida portadora de certos valores estéticos...

Este artículo presenta los conceptos de agenciamiento y phylum maquínico, concebidos por Gilles Deleuze y Felix Guattari, para subrayar el silicio dentro del agenciamiento contemporáneo hombre-naturaleza. El silicio (Si), resalte el campo de la microelectrónica, se convierte en materia expresiva de una ética y de una estética propias. Con el propósito de cartografiar las fuerzas que se ponen a la acción en algunos agenciamientos hombre-silicio, busca crear una imagen-pensamiento tributaria de una estética del silicio, que expresa un modo de existencia. En este camino, se asignan algunas líneas de sostentación de una sociedad de control y otras líneas que actúan en ruptura de la misma. Con el arte, a la edad de informatización planetaria, se vislumbran líneas orientadas a una nueva procesualidad creativa y singularizante, capaces de promover cambios en los posicionamientos del hombre por una vida portadora de ciertos valores estéticos...

In this article we introduce the concepts of arrangement and machinic phylum, created by Gilles Deleuze and Felix Guattari, to underline the silicon inside the contemporary arrangement Man-Nature. Silicon (Si), the highlight of microelectronics, becomes expressive subject of an ethics and an aesthetic. In order to map the forces in action in some arrangements Man-Silicon, we seek to create a thought-image of a silicon aesthetic, which expresses a mode of existence. In this way, we map a few support lines of a control society and others which act in breach with that. With art, at the age of planetary computerization, we find lines oriented to a new creative and singularity process, able to promote changes in man's positions, toward to another mode of existence carried with some aesthetic values...

[Accuracy of platelet counting by optical and impedance methods in patients with Thrombocytopaenia and Microcytosis]

Objectives: Obtaining accurate platelet counts in microcytic blood samples is challenging, even with the most reliable automated haematology analysers. The CELL-DYN[TM] Sapphire [Abbott Laboratories, Chicago, Illinois, USA] analyser uses both optical density and electronic impedance methods for platelet counting. This study aimed to evaluate the accuracy of optical density and electrical impedance methods in determining true platelet counts in thrombocytopaenic samples with microcytosis as defined by low mean corpuscular volume [MCV] of red blood cells. Additionally, the impact of microcytosis on platelet count accuracy was evaluated

Methods: This study was carried out between February and December 2014 at the Haematology Laboratory of the Sultan Qaboos University Hospital in Muscat, Oman. Blood samples were collected and analysed from 189 patients with thrombocytopaenia and MCV values of <76 femtolitres. Platelet counts were tested using both optical and impedance methods. Stained peripheral blood films for each sample were then reviewed as a reference method to confirm platelet counts. Results: The platelet counts estimated by the impedance method were on average 30% higher than those estimated by the optical method [P <0.001]. The estimated intraclass correlation coefficient was 0.52 [95% confidence interval: 0.41-0.62], indicating moderate reliability between the methods. The degree of agreement between methods ranged from -85.5 to 24.3 with an estimated bias of -30, suggesting that these methods generate different platelet results

Conclusion: The impedance method significantly overestimated platelet counts in microcytic and thrombocytopaenic blood samples. Further attention is therefore needed to improve the accuracy of platelet counts, particularly for patients with conditions associated with microcytosis

A Combined Optical Positioning Method Based on 1-D and 2-D Cameras / 生物医学工程学杂志

Optical positioning system has a wide range of application in many fields. This paper presents an optical positioning method which combines linear and plane cameras. 1-D image signal of linear camera is used to get 1-D coordinates of the targets, which can be processed quickly. We can use it to assist processing the 2-D image signals of plane camera under some constraints. Linear camera can reduce the amount of position searching and calculation in coordinates extracting of targets in 2D image, and it can also help identify multiple targets. The results showed that our method could reach an accuracy of 1.608 mm, which was about one thousandth of the measurable range, and the reconstruction time for 4 targets without geometric constraints is 23.87 ms, namely 41.9 fps.

Comparison of Biometric Measurements and Refractive Results between Applanation Ultrasonography and Three Different Interferometries

PURPOSE: To compare ocular biometry and refractive results measured using conventional applanation ultrasonography and 3 different optical interferometries, Lenstar LS900(R), AL-Scan(R) and OA-2000(R). METHODS: The biometries of 31 cataractous eyes were measured using ultrasonography, Lenstar LS900(R), AL-Scan(R) or OA-2000(R). The axial length, anterior chamber depth and keratometry were measured. The SRK/T formula was used to calculate intraocular lens power. Two months after cataract surgery, the refractive outcome was determined and results from the 4 different biometry methods were compared. RESULTS: Axial lengths were 23.39 +/- 0.95 mm, 23.42 +/- 0.98 mm, 23.43 +/- 0.98 mm and 23.44 +/- 0.98 mm measured using ultrasonography, Lenstar LS900(R), AL-Scan(R) and OA-2000(R), respectively with no statistically significant differences observed (p = 0.996). The anterior chamber depth and keratometry were 3.14 +/- 0.41 mm, 3.10 +/- 0.38 mm and 3.13 +/- 0.39 mm (p = 0.936) and 44.41 +/- 1.52 D, 44.54 +/- 1.57 D and 44.44 +/- 1.52 D (p = 0.937) for Lenstar LS900(R), AL-Scan(R) and OA-2000(R) respectively. There were no statistically significant differences between the 3 optical devices. The mean absolute error of the 4 different devices were not statistically significant (p = 0.722). CONCLUSIONS: The ocular biometric measurements and prediction of postoperative refraction using ultrasonography, Lenstar LS900(R), AL-Scan(R) or OA-2000(R) showed no significant differences.

A leitura de pessoas com baixa visão adquirida sob o processo de reabilitação / Reading of people with acquired low vision under the rehabilitation process / La lectura de personas con baja visión adquirida en el proceso de rehabilitación

Objetivo: determinar como sujeitos com baixa visão adquirida que participaram do processo de reabilitação utilizam a leitura em sua vida diária. Método: A investigação foi realizada através de pesquisa descritiva e transversal. A população foi composta por sujeitos com baixa visão adquirida que participaram do Programa de adultos e adolescentes de Reabilitação do CEPRE /FCM /Unicamp em 2008. Foi aplicado um questionário por entrevista, desenvolvido por pesquisa exploratória. Resultados: População constituída por 30 sujeitos. Verificou-se que a maioria dos indivíduos (75,2%) declarou não ser capaz de compreender o texto na primeira vez em que lê, mas apenas 68,7% da população declarou ter a necessidade de ler o texto novamente. Os motivos que levaram 30,0% dos indivíduos a abandonar a leitura foram a dificuldade de ver e a fadiga ocular. Conclusão: O abandono de atividades de leitura e a dificuldade para entender o texto, justificam a necessidade de enfatizar o trabalho de leitura durante o processo de reabilitação...

Aim: to determine how subjects with acquired low vision that participated in the rehabilitation process used reading in their daily life. Method: Investigation was performed through descriptive and transversal survey. Population was composed of 30 subjects with acquired low vision that underwent the Adults and Teens Rehabilitation Program of Cepre/FCM/Unicamp in 2008. A questionnaire was applied through interview, resulting from exploratory survey. Results: Most subjects (75,2%) declared they are not able to comprehend the text on the first reading, but only 68,7% of this population declared having the need to read the text again. The reasons why 30,0% of the subjects abandoned the reading were the difficulty of seeing and the eyestrain. Conclusion: The abandon of reading activities and the difficulty in understanding the text to be read, justify the need to emphasize the work on reading during the rehabilitation process...

Objetivo: determinar como sujetos con baja visión adquirida, que participaron de un proceso de rehabilitación, utilizan la lectura en su vida diaria. Método: La investigación se realizó mediante estudio descriptivo y transversal. La población estaba compuesta por personas con baja visión adquirida que participaron del Programa de Rehabilitación para adultos y adolescentes del CEPRE/FCM/UNICAMP, en el año 2008. Se aplicó un cuestionario desarrollado para investigación exploratória. Resultados: La población era de 30 sujetos. Se encontró que la mayoría de los sujetos (75,2%) declaró no ser capaz de comprender el texto en la primera lectura, y 68,7% de esta población declaró tener la necesidad de leer el texto de nuevo. Las razones que llevaron a 30,0% de los sujetos a abandonar la lectura era la dificultad de ver y la fatiga visual. Conclusión: El abandono de las actividades de lectura y la dificultad para comprender el texto a ser leído, justifican la necesidad de enfatizar el trabajo de lectura durante el proceso de rehabilitación...

Real-time in situ three-dimensional integral videography and surgical navigation using augmented reality: a pilot study / 国际口腔科学杂志·英文版

To evaluate the feasibility and accuracy of a three-dimensional augmented reality system incorporating integral videography for imaging oral and maxillofacial regions, based on preoperative computed tomography data. Three-dimensional surface models of the jawbones, based on the computed tomography data, were used to create the integral videography images of a subject's maxillofacial area. The three-dimensional augmented reality system (integral videography display, computed tomography, a position tracker and a computer) was used to generate a three-dimensional overlay that was projected on the surgical site via a half-silvered mirror. Thereafter, a feasibility study was performed on a volunteer. The accuracy of this system was verified on a solid model while simulating bone resection. Positional registration was attained by identifying and tracking the patient/surgical instrument's position. Thus, integral videography images of jawbones, teeth and the surgical tool were superimposed in the correct position. Stereoscopic images viewed from various angles were accurately displayed. Change in the viewing angle did not negatively affect the surgeon's ability to simultaneously observe the three-dimensional images and the patient, without special glasses. The difference in three-dimensional position of each measuring point on the solid model and augmented reality navigation was almost negligible (<1 mm); this indicates that the system was highly accurate. This augmented reality system was highly accurate and effective for surgical navigation and for overlaying a three-dimensional computed tomography image on a patient's surgical area, enabling the surgeon to understand the positional relationship between the preoperative image and the actual surgical site, with the naked eye.

Optical aids for low vision: use of the Internet to guide teachers of the visually impaired / Auxílios ópticos para baixa visão: uso de internet na orientação de professores de deficientes visuais

PURPOSES: To describe and interpret teachers' opinions about and responsiveness to guidance on optical aids for low vision. METHODS: It was conducted a cross-sectional analytical study. The convenience, non-random sample consisted of 58 teachers from the public school network of the city of Campinas. It was constructed and applied a structured questionnaire, available online at the assessed website. For qualitative data collection it was conducted an exploratory study using the focus group technique. RESULTS: Responses expressed, for the most part, a marked interest in the website, its easiness of access, and the comprehensive nature of the information provided. Most people reported frequent use of the Internet to seek information, and found it easier to access the Internet at home. Among the qualitative aspects of the evaluation, we should mention the perceived importance of the website as a source of information, despite some criticism about the accessibility and reliability of the information found on the Internet. CONCLUSION: Teachers' need for training to deal with visually impaired students and their positive response to advice and information lead to the conclusion that web-based guidelines on the use of optical aids were considered beneficial to ease the understanding of visual impairment and the rehabilitation of the affected subjects.

OBJETIVOS: Descrever e interpretar opiniões e receptividade de professores a orientações sobre auxílios ópticos para baixa visão. MÉTODOS: Caracterizou-se como estudo transversal analítico. A amostra por conveniência, não randômica, foi constituída por 58 professores do sistema público de ensino, no município de Campinas. Aplicou-se questionário estruturado, disponibilizado on-line no site objeto de estudo. Realizou-se também estudo exploratório de abordagem qualitativa, com aplicação da técnica de grupo focal. RESULTADOS: Predominaram as opiniões de muito interesse no site; facilidade e suficiência de informações oferecidas. A maioria reportou uso frequente da internet para buscar informações; consideraram mais fácil acessar a internet na própria residência. Quanto aos aspectos qualitativos da avaliação, evidenciou-se o reconhecimento da importância do site como fonte de informações, embora existissem restrições quanto à facilidade de acesso e confiabilidade de informações veiculadas na internet. CONCLUSÃO: A necessidade de preparo em relação à deficiência visual, declarada pelos professores e a receptividade a orientações e informações, permitem concluir pelo benefício de orientações divulgadas pelo website sobre uso de auxílios ópticos, o que facilita a compreensão de problemas visuais e a reabilitação em baixa visão.

Intubación de paciente despierto con fibroscopio rígido bajo sedación con remifentanil / Rigid fiberscope intubation of a patient awake with remifentanil sedation

Introducción. Al elegir el manejo de un paciente con vía aérea difícil, conocida o sospechada, es importante plantearse alternativas de intervención. Varios algoritmos de manejo, recomiendan la intubación con paciente despierto, con laringoscopia directa o instrumentos ópticos. Los estiletes rígidos y semirrígidos son dispositivos ópticosdesarrollados para el manejo de la vía aérea difícil, que han mostrado ser rápidos, atraumáticos y confiables. Objetivos. Describir el uso de diferentes estrategias de abordaje de la vía aérea difícil en el escenario de cirugía urgente, al utilizar como una de las opciones de manejo el dispositivo Airway RIFL (rigid intubation fiberoptic laryngoscope). Metodología y resultados. Este es el caso de un paciente de 69 años, llevado de urgencia a cirugía para hemostasia de lesión neoplásica en tórax, considerado como vía aérea difícil por antecedente de múltiples resecciones de lesiones tumorales y radioterapia en vía aérea, con secuela de marcada deformidad facial. Intubación con estómago lleno. Se plantea como primera opción en el manejo de la via aérea el uso de anestesia tópica, sedación con remifentanil y laringoscopia directa, lo cual no es posible por limitada apertura oral: se intenta en tres ocasiones intubación nasal, la cual es fallida. Se decide intubación con el dispositivo Airway RIFL, la cual es exitosa. Conclusiones. Dentro del enfoque del paciente considerado como vía aérea difícil, contar con varias estrategias de manejo, la analgesia local y la sedación, permiten una excelente colaboraciónpor parte del paciente y una rápida intubación orotraqueal con fibroscopio rígido, incluso en escenarios de urgencia.

Introduction. When choosing the appropriate management for a difficult airway patient, either established or suspected, several intervention optionsshould be considered. Some management algorithms recommend awake intubation under direct laryngoscopy or optical instruments. Rigid and semi-rigid stylets are optical devices developed for managing the difficult airway that have proven to be fast, non-traumatic and reliable.Objectives. To describe the use of different strategies to approach the difficult airway in an emergency surgery, using the Airway RIFL (rigidintubation fiberoptic laryngoscope) as one of the options. Methodology and results. This is a case of a 69-yr old patient admitted to the ER for hemostasis and surgery of a chest neoplasia. The patient was considered a difficult airway patient because of a history of multiple tumor resectionsand radiotherapy in the airway, resulting in a notorious facial deformity. Intubation on a full stomach. Topical anesthesia was considered the first choice for airway management, remifentanil sedation and direct laryngoscopy but this is not possible due to a limited oral opening: three nasalintubation attempts were made but failed. Then it was decided to use the Airway RIFL device and the procedure was successful. Conclusions. When dealing with a difficult airway patient, having several management strategies at hand, local anesthesia and sedation,allow for excellent patient collaboration and a fast orotracheal intubation using a rigid fiberscope, even under emergency situations.

A importância do treinamento da criança com baixa visão, com emprego dos auxílios ópticos, para capacitação educacional: relato de caso / The value of optical aids' training for low vision child education: case report

O aprendizado do correto manuseio do auxílio óptico foi treinado: localização, focalização e seguimento com o telescópio de 8x de magnificação. Após essa etapa iniciou-se o aprendizado de cópia da lousa com o auxílio adaptado. Totalizaram-se 17 sessões para a criança receber a prescrição final devido às grandes dificuldades apresentadas pela baixa acentuada das funções visuais.

Training of the proper handling of optical devices was performed: location, targeting and tracking with the 8x magnification telescope. After this step, learning to a copy from a blackboard with the adapted optical aid was initiated. Seventeen sessions were required for the child's final prescription due to severe low vision and loss of visual functions.

Resultados preliminares de um sistema computadorizado e estereoscópico para pupilometria in vivo / Preliminary results of a computerized and stereoscopic system for in vivo pupillometry

OBJETIVOS: Desenvolver um sistema digital, com capacidade de induzir acomodação, para medida do diâmetro e formato da pupila para dez diferentes níveis de iluminação (LUX), variando do nível mesópico ao fotópico. MÉTODOS: Um sistema óptico para conjugar imagens da pupila iluminada por LED infravermelho e branco foi projetado e montado usando um capacete típico de oftalmoscópio e uma máscara típica de mergulhador como suporte e uma câmera CCD de alta resolução e sensibilidade. Algoritmos usando princípios de processamento de imagens foram implementados para leitura do arquivo de vídeo e a detecção automática do centro geométrico e diâmetro da pupila para cada quadro. RESULTADOS: Apresentamos dados preliminares deste sistema para um paciente voluntário. Os dados sobre posição horizontal (x), vertical (y) do centro geométrico e do diâmetro da pupila foram exportados para arquivos texto que podem ser impressos usando um programa convencional de planilha (Excel). O processo de acomodação é garantido por uma mira virtual (LED branco) localizada a 6 metros do olho do paciente e o nível de iluminação é precisamente controlado por uma placa eletrônica que alimenta o LED central que tem sua potência controlada pelo "software". CONCLUSÕES: Com o instrumento desenvolvido dados precisos da posição e tamanhos da pupila podem então ser obtidos estereoscopicamente (para ambas as pupilas e ao mesmo tempo) para qualquer paciente. Acreditamos que tal instrumento possa ser útil em algumas práticas oftálmicas onde as características geométricas da pupila sejam importantes.

PURPOSE: We developed a digital system with accommodation capacities for measurement of the diameter and shape of the in vivo pupil for 10 different levels of illumination intensity, varying from mesopic to photopic. METHODS: An optical system for conjugating images from an infrared and white light illuminated pupil was designed and mounted using an ophthalmoscope helmet and a typical diving mask as support for a high-resolution and sensitivity CCD. Using an IBM compatible computer sequences of video in AVI format were digitized for several seconds at a mean rate of 30 Hz. Algorithms using principles of image processing were implemented for detection of the pupil edges. RESULTS: We present preliminary results of this system for a voluntary patient. Data for the horizontal (x) and vertical (y) central position and for the diameter of the pupil were then exported to files that could be read by typical spread sheet programs (Excel). CONCLUSIONS: In this manner, precise data can be obtained stereoscopically (for both pupils at the same time) for any patient, given that the accommodation process is guaranteed by using a white LED virtual mire located 6 meters from the patient's eye. An electronic board precisely controls the level of illumination. We believe here developed instrument may be useful in certain ophthalmic practices where precise pupil geometric data are needed.

Thoracoscopic Approach to the Thoracic Spine / 한양의대학술지

Nowadays, the minimally invasive technique is the current trends in all medical fields. The spine is not the exception. By the development of modern optical devices and computer technology, thoracoscopy arose as new powerful tool in thoracic area. Many spinal disorders which were previously treated by transthoracic surgery are entering into the area of thoracoscopic surgery. The indication for thracoscopic surgery is getting wider and wider as technologies progress. So it seems to be difficult to define its indication strictly, as long as the patient can tolerate one-lung ventilation and endoscopy is accessible. In thoracic discectomy, thoracoscopy not only shortened operation time, hospital stay and chest tube insertion duration, but also lowered medical expense, postoperative pain and complication rate. But the patient selection is not yet established. Corpectomy can be performed in metastatic tumor removal or debridement of osteomyelitis by thoracoscopy. Thereafter, reconstruction or instrumentation is possible to prevent postoperative spinal deformity. In correction of spinal deformity, thoracoscopic surgery showed similar outcomes compared to thoracotomy in deformity correction, bone fusion, and functional outcome. There was also no statistical difference in complication rates between them. Pulmonary complications seen in thoracoscopic surgery such as atelectasis, pneumothorax and hemothorax were common. They seem to be related with the one-lung ventilation and the thoracoscopic approach itself, distinct from thoracotomy. But most complications were not life-threatening with some exceptions. Considering the development during the past two decades, the speed of development of thoracoscopic surgery will accelerate and the role of thoracoscopic surgery will become more important. In the development of thoracoscopy, the technical progression of optics and computer engineering will play important roles.

Anesthesia for Transthoracic Endoscopic Sympathectomy / 대한마취과학회지

Technological advances in video camera, high resolution monitors and optical systems have produced considerable process in endoscopic surgery. Recently we have experienced transthoracic endoscopic sympathectomy(TES) for the treatment of Buerger's disease of both hands in a 47 years old male healthy patient. For the TES, one lung ventilation is necessary to provide adequate surgical access, so this patient had general anesthesia with a disposable left sided Robertshaw double lumen endobronchial tube. The patient was monitored for arterial pressure, herat rate, ECG, pulse oximetry, end-tidal carbon dioxide concentration, peak inspired airway pressure and arterial blood gas analysis. Potenial intraoperative problems wese hypoxemia during one-lung anesthesia, hypotension and hypercarbia occurred by insufflation of carbon dioxide into the chest cavity. Our patient also developed moderate hypoxemia which was corrected by application of high frequency jet ventilation with low driving pressure during right sided operation, and increased significantly arterial carbon dioxide tension about 8-12 mmHg during one lung ansthesia. We reviewed our experience and discussed the anesthetic technique and perioperative problems encounterd in the patient undergoing transthoracic endoscopic sympathectomy for Buerger's disease.

Posterior Chamber Intraocular Lens Implantation in front of the Anterior Lens Capsule during Pars Plana Lensectomy and Vitrectomy

Many patients present simultaneously with visually significant (to the patient and surgeon) lens opacities and vitreoretional disease. Traditional management of this problem has included two operations: vitrectomy followed by cataract extraction or cataract extraction followed by vitrectomy. Visual rehabilitation of aphakic eyes after pars plana vitrectomy is often difficult when anatomic objectives are achieved. Intraocular lens provides more natural and convenient vision. Now, simultaneous cataract extraction and lens implantation during pars plana vitrectomy can be considered. We performed posterior chamber lens insertion in the ciliary sulcus after completion of pars plana lensectomy, vitrectomy, and removal of intraocular foreign body. During pars plana lensectomy, we left the anterior lens capsule and zonules intact. After posterior chamber lens insertion, we removed the central anterior lens capsules from behind the optical component leaving a peripheral rim to support the haptics. The procedure provided good pseudophakic vision.

Melanosome in Retinal Pigment Epithelium: Distribution, Type and Activity of Acid Phosphatase

Distribution of melanosome, types of melanosome in retinal pigment epithelium(RPE) and activity of acid phosphatase in melanosome were studied in rabbits. The eyes were observed using electron microscopy and enzyme cytochemical electron microscopy. The majority of melanosomes were located near the apical region of RPE. So melanosomes can absorb light that passes through the neural retina rapidly and remove free radicals that develop in RPE effectively, thereby benefiting the optical system and protecting visual outer segments. Melanosomes in RPE were classified as two types; ellipsoid and spherical or oval. Ellipsoid types were loccated parallel to the apical process and spherical or oval types, vertically or obliquely to apical process. Mature and immature melanosome showed mostly positive responses for activity of acid phosphatase, indicating that melanosome commonly incorporates into the lysosomal system of the retinal pigment epithelium. But some melanosomes showed negative responses for activity of acid phosphatse, suggesting that melanosome has a stable and inert property. The observed premelanosome showed negative response. Two types of melanosomerelated complex granules were identified: melanosome with a cortex of enzymereactive material(melanolysosome) and melanosome with a cortex of lipofuscin(melanolipofuscin). They were located near or below the melanosomes in the cytoplasm. These findings indicate that a relationship between melanosome and the lysosomal system of the retinal pigment epithelium exists, and suggest that melanosome undergoes modification or degradation there. Also, the findings of premelanosome and positive responses for the activity of acid pnosphatase indicate that melanosome continues to be synthesized at a low rate in adult eye.

Melanosome in Retinal Pigment Epithelium: Distribution, Type and Activity of Acid Phosphatase

Distribution of melanosome, types of melanosome in retinal pigment epithelium(RPE) and activity of acid phosphatase in melanosome were studied in rabbits. The eyes were observed using electron microscopy and enzyme cytochemical electron microscopy. The majority of melanosomes were located near the apical region of RPE. So melanosomes can absorb light that passes through the neural retina rapidly and remove free radicals that develop in RPE effectively, thereby benefiting the optical system and protecting visual outer segments. Melanosomes in RPE were classified as two types; ellipsoid and spherical or oval. Ellipsoid types were loccated parallel to the apical process and spherical or oval types, vertically or obliquely to apical process. Mature and immature melanosome showed mostly positive responses for activity of acid phosphatase, indicating that melanosome commonly incorporates into the lysosomal system of the retinal pigment epithelium. But some melanosomes showed negative responses for activity of acid phosphatse, suggesting that melanosome has a stable and inert property. The observed premelanosome showed negative response. Two types of melanosomerelated complex granules were identified: melanosome with a cortex of enzymereactive material(melanolysosome) and melanosome with a cortex of lipofuscin(melanolipofuscin). They were located near or below the melanosomes in the cytoplasm. These findings indicate that a relationship between melanosome and the lysosomal system of the retinal pigment epithelium exists, and suggest that melanosome undergoes modification or degradation there. Also, the findings of premelanosome and positive responses for the activity of acid pnosphatase indicate that melanosome continues to be synthesized at a low rate in adult eye.