Optic Capture Research Articles

Capsule Membrane Suture Fixation of Decentered Sulcus Intraocular Lenses

Different surgical methods are used to fixate the subluxated sulcus intraocular lens (IOL) in the absence of in-bag fixation, ranging from iris and scleral suturing to optic capture of the IOL. A new technique, which we have termed capsule membrane suture fixation, provides an additional method for securing a subluxated or decentered sulcus-based IOL to the remnant capsule or a capsular membrane. This method can also be used in secondary surgery for fixation, repositioning, or removal and replacement of IOLs. In this technique, the IOL haptics are sutured to the fibrotic elements of the capsular membrane to center and secure the IOL to the capsular membrane and prevent complications associated with uveal touch.

Oval capsulorhexis for phacoemulsification in posterior polar cataract with preexisting posterior capsule rupture

We describe use of an oval capsulorhexis rather than the conventional circular capsulorhexis for phacoemulsification in posterior polar cataract with preexisting posterior capsule rupture. An oval capsulorhexis minimizes the turbulence in the capsular bag by increasing the area available for efflux of fluid. It also enables end-to-end nuclear sculpting, removal of the nuclear fragment from the bag, intraocular lens (IOL) implantation, and vitrectomy without stretching the capsular bag. The smaller axis of the oval capsulorhexis facilitates optic capture of a sulcus-fixated IOL. The oval capsulorhexis can be used safely for phacoemulsification of all grades of nuclear sclerosis in posterior polar cataract with preexisting posterior capsule rupture.

Pseudophakic negative dysphotopsia: Surgical management and new theory of etiology

To evaluate the benefit of various surgical methods to address pseudophakic negative dysphotopsia. Private practice, Los Angeles, California, USA. Interventional case series. The following 4 surgical methods were used to treat negative dysphotopsia: secondary piggyback intraocular lens (IOL) implantation, reverse optic capture, in-the-bag IOL exchange, and iris suture fixation. Ultrasound biomicroscopy (UBM) was used to analyze posterior chamber anatomy. The primary outcome was partial or complete resolution of the negative dysphotopsia symptoms 3 months postoperatively. Twelve eyes of 11 patients with negative dysphotopsia had surgical treatment. All 10 patients who had piggyback IOL implantation or reverse optic capture had partial or complete resolution of symptoms by 3 months. No patient who had in-the-bag IOL exchange (n = 3) or iris suture fixation of the capsular bag-IOL complex (n = 1) improved despite alteration of IOL material or edge design in the case of IOL exchange or UBM confirmation of posterior chamber collapse in the case of iris suture fixation of the capsular bag-IOL complex. Consistent with a new hypothesis, resolution of negative dysphotopsia symptoms depended on IOL coverage of the anterior capsule edge rather than on collapse of the posterior chamber alone. Furthermore, negative dysphotopsia was not attributed to a particular IOL material or edge design. .

Glued intraocular lens implantation for eyes with defective capsules: A retrospective analysis of anatomical and functional outcome

Purpose To analyze the anatomical and functional outcome of glued intra ocular lens (IOL) implantation technique and its modifications. Design Retrospective observational case series. Methods This is a retrospective analysis of the patients who underwent glued intra ocular lens implantation from December 2007 to August 2010. Post operative uncorrected vision, best corrected visual acuity (BCVA), intra ocular pressure, IOL position, endothelial cells and anterior chamber reaction at their last follow up are analyzed from their concerned case sheets documentation. Subjective changes are analyzed via individual questionnaire. Immediate and late postoperative complications are also evaluated. Surgical modifications and the difference in the operated eyes are analyzed. Results Total 210 glued IOL eyes have been reviewed. Out of this 210, there are 152 (PMMA glued IOL), 21 (three piece foldable IOL), 5 (multifocal foldable IOL), 12 (pediatric glued IOL), 5 (20G sutureless vitrectomy), 2 (glued iris prosthesis) and 3 (transposition of posterior chamber IOL into anterior chamber). In combined surgeries there are, 5 (optical penetrating keratoplasty), 2 (descemet’s stripping endothelial keratoplasty) and 3 (iridoplasty). The modifications in glued IOL are handshake technique, injectable or foldable glued IOL, Multifocal glued IOL and intraoperative 23/25G trocar cannula infusion. Decentration (1.97%), macular edema (1.97%) and optic capture (2.63%) are the post operative complications encountered in rigid glued IOL. Good patient satisfaction is seen in the eyes with IOL repositioning, IOL exchange and multifocal glued IOL. There is significant improvement in BCVA in PMMA IOL ( p = 1.35 × 10 −5) and foldable IOL ( p = 0.000). Conclusion Glued IOL seems to be a good alternative in IOL implantation in eyes with deficient capsules. The modifications in the existing technique decrease the learning time and risk for complications.

Supracapsular implantation with optic capture of posterior chamber intraocular lens in aphakic school-age children after traumatic cataract

To assess the clinical effects of supracapsular implantation with optic capture of the posterior chamber intraocular lens in school-age children with traumatic cataract. It was a retrospective case series study. Thirteen cases (13 eyes) received posterior curvilinear capsulorhexis with optic capture of the posterior chamber intraocular lens. Pre- and post-operative visual acuities were recorded. Intra-o and post-operative complications were observed. The follow-up period ranged from 6 to 42 months. Implantation of optic capture of the posterior chamber intraocular lens was successfully performed in 13 eyes. The best-corrected-visual acuity ranged from 0.2 to 1.0. No optic axis opaque was found in 10 eyes with optic capture. The major complications of optic capture were lenticular precipitates and posterior synechia of the iris. Intraocular dislocation was found in one case two weeks after the operation. Supracapsular implantation with optic capture of the posterior chamber intraocular lens is safe and effective for the treatment of traumatic cataract in school-age children.

Optic capture in the anterior capsulorhexis during combined cataract and vitreoretinal surgery

We describe an optic capture technique that can be used during combined cataract and vitreoretinal surgery if in-the-bag implantation of an intraocular lens (IOL) is not possible. The IOL is placed in the ciliary sulcus, and optic capture is performed behind an intact anterior continuous curvilinear capsulorhexis, with the haptics remaining in the sulcus. The technique maintains IOL stability and separation of the anterior and posterior segments intraoperatively and postoperatively.

Multifocal intraocular lens optic anteriorization capture to correct residual refractive error

To evaluate the efficacy and safety of capturing the intraocular lens (IOL) optic through the anterior capsulorhexis opening in eyes with multifocal IOLs and a residual refractive error. Hospital Oftalmológico de Brasília, Brasília, Brazil. Eyes with previous cataract surgery and Tecnis ZM900 multifocal IOL implantation were prospectively analyzed. After at least 1 month, patients had second surgery in which the IOL optic was captured through the anterior capsulorhexis opening to correct the residual refractive error. Preoperative and postoperative examinations at 1 day and 3 months included spherical equivalent (SE); uncorrected distance (UDVA), near (UNVA), and intermediate (UIVA) visual acuities; and corrected distance visual acuity (CDVA). The study included 16 eyes of 14 patients. The mean UDVA was 0.32 logMAR preoperatively and 0.10 logMAR after anterior optic capture and the mean SE, +1.09 diopters (D) and +0.26 D, respectively; both improvements were statistically significant (P<.001). The change in CDVA and UNVA from before anterior optic capture to the last follow-up was not statistically significant. The UIVA was significantly worse postoperatively (P = .011). No eye lost lines of CDVA. One eye (6.25%) developed glaucoma postoperatively. At the last follow-up, 13 patients (92.85%) were spectacle-independent for near and distance vision. Early outcomes indicate that anterior optic capture is a safe, accurate procedure in eyes with multifocal IOLs and a mild hyperopic residual refractive error postoperatively.

손 동작 인식을 통한 인간 - 컴퓨터 인터페이스용 저가형 비주얼 모션 데이터 글러브

The motion data glove is a representative human-computer interaction tool that inputs human hand gestures to computers by measuring their motions. The motion data glove is essential equipment used for new computer technologiesincluding home automation, virtual reality, biometrics, motion capture. For its popular usage, this paper attempts to develop an inexpensive visual.type motion data glove that can be used without any special equipment. The proposed approach has the special feature; it can be developed as a low-cost one becauseof not using high-cost motion-sensing fibers that were used in the conventional approaches. That makes its easy production and popular use possible. This approach adopts a visual method that is obtained by improving conventional optic motion capture technology, instead of mechanical method using motion-sensing fibers. Compared to conventional visual methods, the proposed method has the following advantages and originalities Firstly, conventional visual methods use many cameras and equipments to reconstruct 3D pose with eliminating occlusions But the proposed method adopts a mono vision approachthat makes simple and low cost equipments possible. Secondly, conventional mono vision methods have difficulty in reconstructing 3D pose of occluded parts in images because they have weak points about occlusions. But the proposed approach can reconstruct occluded parts in images by using originally designed thin-bar-shaped optic indicators. Thirdly, many cases of conventional methods use nonlinear numerical computation image analysis algorithm, so they have inconvenience about their initialization and computation times. But the proposed method improves these inconveniences by using a closed-form image analysis algorithm that is obtained from original formulation. Fourthly, many cases of conventional closed-form algorithms use approximations in their formulations processes, so they have disadvantages of low accuracy and confined applications due to singularities. But the proposed method improves these disadvantages by original formulation techniques where a closed-form algorithm is derived by using exponential-form twist coordinates, instead of using approximations or local parameterizations such as Euler angels.

Intérêt de l’implant « bag-in-the-lens » dans la chirurgie de la cataracte de l’enfant

Evaluate the advantages of the bag-in-the-lens intraocular lens in children undergoing cataract surgery. This prospective study included 54 eyes of 37 children and babies (age, 2 months to 14 years), consecutively operated on between December 1999 and January 2008 for unilateral or bilateral cataract using the "bag-in-the-lens" intraocular lens. Slit-lamp examination, intraocular pressure, visual acuity, and refraction were followed to the best possible degree over time. The mean age of the 37 children at the last consultation visit was 8.3+/-4.9 years. The mean visual acuity improved from 0.2+/-0.1 to 0.8+/-0.3. On the other hand, visual acuity improvement in children presenting hyperplastic persistence of the vitreous was less favorable with a postoperative average visual acuity of 0.14+/-0.18. The mean postoperative refraction in 13 children (26 eyes) operated on for bilateral cataract was 0.5+/-1.5 D for eyes showing axial lengths with substantial variation. The refraction was stable over time in children over 2 years of age. Once the implant was positioned correctly, the remaining epithelial cells of the lens did not migrate toward the visual axis, which was the case in 93.8% of all eyes and in 100% of children over 1 year of age. The "bag-in-the-lens" implant is particularly indicated in children in whom posterior rhexis and optic capture have been recommended since 1994. The implantation minimizes the use of anterior vitrectomy in pediatric cataract surgery, limiting it to those eyes presenting a proliferative hyperplastic vitreous.

Comparison of 2 techniques of intraocular lens implantation in pediatric cataract surgery

To compare the results of 2 intraocular lens (IOL) implantation techniques in pediatric cataract surgery. Labbafinejad Medical Center, Tehran, Iran. This contralateral prospective randomized study comprised children with bilateral congenital or developmental cataract. In all cases, anterior capsulorhexis, lens aspiration, posterior continuous curvilinear capsulorhexis (PCCC), and anterior vitrectomy were performed. In 1 eye of each patient, a 3-piece AcrySof MA60BM IOL was implanted in the capsular bag. In the other eye, the same type of IOL was implanted in the ciliary sulcus and the optic was captured through the PCCC. Visual acuity, visual axis opacification, and complications were assessed. Twenty-eight eyes of 14 children were included in the study. The mean patient age at surgery was 5.1 years +/- 1.5 (SD) (range 2.5 to 8.0 years). The mean follow-up was 22.2 +/- 6.3 months (range 13 to 35 months). The visual axis remained clear in all eyes in both groups. There was no statistically significant difference between the 2 groups in best corrected visual acuity or complications (eg, postoperative uveitis, posterior synechia, significant IOL decentration). In pediatric cataract surgery, placement of haptics in the ciliary sulcus and IOL optic capture through the PCCC was a safe alternative to IOL implantation in the capsular bag.

Capsular Opacification after Vitreous-Sparing Cataract Surgery in Children

The aim of this study was to evaluate different methods of intraocular lens (IOL) implantation and posterior capsule management in the absence of vitrectomy with respect to visual axis opacification (VAO) in children. Seventy-three eyes of African children undergoing cataract extraction and IOL implantation between 1998 and 2001 were evaluated. In all eyes, the IOL haptics were placed in the bag and the vitreous was preserved. The IOL optic and posterior capsule were managed in the following 3 ways: The IOL optic was captured behind the posterior capsule in conjunction with posterior capsulotomy (PC) in 47 eyes (group 1). The IOL optic was implanted in the bag with PC in 14 eyes (group 2) and without PC in 12 eyes (group 3). Cox proportional hazard analysis and Kaplan-Meier survival curves were performed to evaluate the incidence of Elschnig pearls (EP) and VAO. Elschnig pearls developed in 14.9 % of the patients in group 1, in 56.8 % in group 2 and in 91.7 % in group 3. The occurrence of EP depended significantly on optic capture (p < 0.001) and child's age (p < 0.05), but not on PC (p = 0.084) and eye side (p = 0.1). The persistence of visual axis clarity depended significantly on optic capture (p < 0.001) but not on PC. In vitreous-sparing cataract surgery, posterior capsule opening does not effectively prevent VAO unless it is in conjunction with IOL optic capture.

P.009 Restorative treatment of postoperative gingival defects

Purpose: To determine whether anterior vitrectomy is necessary along with primary posterior capsulorhexis in children less than 5 years of age with congenital cataracts.Setting: Iladevi Cataract & IOL Research Centre, Ahmedabad, India.Method: This prospective study comprised 18 eyes of 16 children whose mean age was 2.3 years (range 3 months to 5 years). Primary posterior continuous curvilinear capsulorhexis (PCCC) and posterior chamber intraocular lens (IOL) implantation were performed in all eyes. No vitrectomy was done in 8 eyes (Group 1); an anterior vitrectomy was performed in 10 eyes (Group 2). Optic capture through the posterior capsule was achieved in 3 eyes in Group 1 and in 5 eyes in Group 2. Average follow-up was 13.3 months.Results: Five eyes (62.5%) in Group 1 needed secondary pars plana vitrectomy because the visual axis was obscured; no eye in Group 2 needed a secondary procedure. Four Group 1 eyes developed significant complications (updrawn pupil, decentration, occlusio pupillae, transient glaucoma). While no Group 2 eye developed a serious complication, some degree of pigment dispersion was noted in all the eyes.Conclusion: The results suggest that anterior vitrectomy is desirable along with primary PCCC in children younger than 5 years with congenital cataracts.

Predictability of Intraocular Lens Calculation Using the Holladay II Formula after in-the-Bag or Optic Captured Posterior Chamber Intraocular Lens Implantation in Paediatric Cataracts

Purpose: To assess the predictability of postoperative refraction using the Holladay II-formula in paediatric patients randomized to undergo 2 different surgical procedures. Methods: Fourty cataractous eyes of 29 patients (age 2.31–11.75 years) were operated with in-the-bag intraocular lens implantation. Randomly, either an anterior vitrectomy (group A, 19 eyes) or posterior optic capture without vitrectomy (group B, 21 eyes) was performed. Randomization was done in 4 separate age groups, in accordance with 4 target refractions (0, 1, 2 and 3 dpt) to compensate for the anticipated myopic shift. Results: The predicted refraction correlated with the achieved postoperative refraction (total group, p = 0.019), closer in group A (p = 0.033) than in group B (p = 0.265); however, the results of groups A and B were not significantly different (p = 0.324). There was a tendency for postoperative targeted hyperopia being underachieved in the youngest patients. Conclusion: The Holladay II formula provides reliable intraocular lens calculation in paediatric cataracts. The tendency to underachieve the target refraction in younger patients needs further investigation.

사실적인 컴퓨터 애니메이션 구현을 위한 증분형 영상 기반 운동 렌더링 기법

사실적인 컴퓨터 애니메이션 제작 시 종종 모션 캡쳐 기술이 사용된다. 모션 캡쳐 기술은 대상체의 운동을 측정해서 모델링한 운동 렌더링 결과를 그래픽스로 표현한다. 본 논문에서는 카메라를 사용해서 얻어진 2차원 영상 정보로부터 대상체의 3차원 운동을 측정하여 모델링하는 영상 기반 운동 렌더링 문제를 다룬다. 기존의 영상 기반 운동 렌더링 알고리즘은 계산량이 너무 많거나 정확도가 떨어지는 등의 단점이 있었다. 첫 번 째 단점은 장편 애니메이션 제작시 제작 시간이 너무 길어서 문제가 되고, 두 번 째 단점은 사실적인 애니메이션 구현시 사실감이 저하되는 문제를 야기 시킨다. 이와 같은 기존 방식의 단점을 보완하기 위하여 본 논문에서는 계산량이 적고 정확도가 높은 영상 기반 운동 렌더링 알고리즘을 제안한다. 본 논문에서 제안한 방식에서는 계산량이 적은 증분형 운동렌더링 알고리즘을 최적제어 이론의 시각에서 분석하여 정확도를 향상시키도록 개조한다. 본 방식을 광학식 모션 캡쳐 기술에 적용할 경우 표시자(marker)의 부착 없이도 모션 캡쳐가 가능하다는 부가적 인 장점 또한 얻을 수 있다. Image-based motion capture technology is often used in making realistic computer animation. In this paper we try to implement image-based motion rendering by fixing a camera to a PC. Existing image-based rendering algorithms have disadvantages of high computational burden or low accuracy. The former disadvantage causes too long making-time of an animation. The latter disadvantage degrades reality in making realistic animation. To compensate for those disadvantages of the existing approaches, this paper presents an image-based motion rendering algorithm with low computational load and high estimation accuracy. In the proposed approach, an incremental motion rendering algorithm with low computational load is analyzed in the respect of optimal control theory and revised so that its estimation accuracy is enhanced. If we apply this proposed approach to optic motion capture systems, we can obtain additional advantages that motion capture can be performed without any markers, and with low cost in the respect of equipments and spaces.

Paediatric cataract surgery

Bilateral congenital cataract is the most common cause of treatable childhood blindness. Nuclear cataract is usually present at birth and is non-progressive, while lamellar cataract usually develops later and is progressive. Prompt surgery has to be performed in cases with dense congenital cataract: if nystagmus has developed, the amblyopia is unfortunately irreversible. A treatment regime based on surgery within 2 months of life, combined with prompt optical correction of the aphakia and occlusion therapy with frequent follow-up, have been successful in both unilateral and bilateral cases. The surgery ought to include anterior and posterior capsulorexis in all children at the present time. Intraocular lens implantation has been safely performed below the age of 1 year and has also been successfully performed in bilateral cases. Anterior dry vitrectomy should be performed in preschool children to avoid visual axis opacification. Visual axis opacification is the most common complication found after cataract surgery in children. Secondary glaucoma is by far the most sight-threatening complication and is, unfortunately, common in the newborn so lifelong follow-up is essential in these cases.

Intraocular lenses in children

Intraocular lenses in children

광학식 모션 캡쳐(Optical Motion Capture)방식을 이용한 디지털 캐릭터 움직임

Motion Capture in multimedia contents of the imagination world is utilized in various field such as game, movie, TV. Motion Capture technology of most of game is utilized. As well as is more realistic if use motion Capture and superior time and monetary aspect than previous key frame (Key-Framing) way as well as can display screen that do dynamic, there is more excellent advantage in qualitative aspect. But, is utilizing in some specialty companies and use example was not informed much about problem when is very lacking, and utilize yet in learned circles. Extract motion data of various action using optic motion Capture of motion Capture equipment in this treatise, and investigated about problem that appear when applied in character that is different from a person.

Combined cataract surgery and 25-gauge sutureless vitrectomy for posterior lentiglobus

Combined cataract surgery and sutureless vitrectomy were performed in a 2-year-old boy with posterior lentiglobus. After an anterior capsulotomy was made, the lens nucleus was aspirated without hydrodissection to avoid posterior capsule rupture. The cortex was carefully aspirated because the central posterior capsule moved up and down during irrigation and aspiration. A pars plana vitrectomy was then performed with the sutureless 25-gauge system for an anterior vitrectomy with a posterior capsulotomy. A +27 diopter AcrySof intraocular lens (IOL) (Alcon) was implanted with the haptics in the bag and the optic behind the posterior capsulotomy with optic capture. Two months postoperatively, the IOL was centered and there were no complications. This surgical technique is easy and effective. It avoids complications, facilitates IOL implantation behind the posterior capsule, and improves the external appearance of the eye immediately postoperatively.

Surgical Results and Complications of Implanted Primary Intraocular Lenses in Pediatric Cataract

Purpose: To evaluate surgical results and complications of different intraocular lenses (IOL) implantation in pediatric cataract surgery. Methods: We retrospectively reviewed 139 eyes of 80 patients who had undergone irrigation and aspiration of cataracts and primary posterior chamber intraocular lens implantation with posterior continuous curvilinear capsulorhexis and optic capture from July 1998 to December 2005. All the eyes were divided into three groups into the intraocular lenses implanated: group 1 (n=40), PMMA lens was implantated; group 2 (n=42), hydrophobic acrylic lens was implantated; group 3 (n=57), hydrophilic acrylic lens was implanated. The surgical results and complications was evaluated. Results: Wound leakage, iris prolapse, shallow anterior chamber during operation were the most common in group 1. Peripheral anterior synechiae, conjuntival cyst, pigment deposition of IOL, exudative membrane, elevated intraocular pressure were also the most common in group 1 (P

"Reverse" optic capture complicating retained viscoelastic in capsular bag following phacoemulsification

"Reverse" optic capture complicating retained viscoelastic in capsular bag following phacoemulsification