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Lan-Hsin Chuang

Publications and source records attributed to Lan-Hsin Chuang.

9 recordsLinked to original sources
PubMed2005

Selective staining of the internal limiting membrane using the sequential intraoperative instillation of whole blood followed by indocyanine green dye.

PURPOSE: To reduce the retention of indocyanine green (ICG) on the retina by selectively staining the internal limiting membrane (ILM) with whole blood during ICG-assisted ILM peeling. DESIGN: Interventional, non-comparative, prospective case series. METHODS: Autologous whole blood was applied to cover the macular area and selectively removed to expose the area needed to be stained. ICG solution (1 mg/ml) diluted in glucose 5% was used to selectively stain the macular area. The stained ILM was removed completely. RESULTS: We studied 22 patients with macular holes, eight with macular pucker and four with diabetic macular edemas. The ILM was selectively stained successfully by ICG with whole blood. One month after surgery, we found no autofluorescence in the posterior pole by infrared-sensitive camera. CONCLUSIONS: Autologous whole blood can help to achieve the goal of selectively staining ILM, further reducing the retention of ICG. It may further reduce ICG toxic effects.

Adult↗
PubMed2005

Prevention of indocyanine green toxicity on retinal pigment epithelium with whole blood in stain-assisted macular hole surgery.

PURPOSE: To examine whether whole blood prevents indocyanine green (ICG) toxicity on in vitro retinal pigment epithelium (RPE) and prevents RPE staining in ICG-assisted macular hole (MH) surgery. DESIGN: In vitro study and prospective case series. PARTICIPANTS: In vitro study and 20 patients who underwent ICG-assisted MH surgery (20 eyes). METHODS: In the in vitro study, cultured human RPE cells were covered with balanced saline solution (BSS), heparinized whole blood, plasma, or packed red blood cells, then exposed to various concentrations of ICG. One cohort was incubated in the dark; the other cohort was exposed to light. Indocyanine green toxicity was evaluated by mitochondrial dehydrogenase assay. In the clinical study, a prospective noncomparative review of 20 consecutive patients (20 eyes) with stage 3 to stage 4 MH who underwent surgery with ICG to stain the internal limiting membrane (ILM) was performed. Indocyanine green solution (0.5 mg/ml) was used to stain the ILM after autologous whole blood covered the macular hole area. Postoperative staining of ICG on RPE was detected by an infrared-sensitive camera. MAIN OUTCOME MEASURES: Cultured human RPE cell viability, macular hole closure rate, median visual acuity preoperatively and postoperatively, postoperative ICG staining, and retinal changes. RESULTS: Cultured human RPE cells covered by whole blood or plasma showed no decrease of mitochondrial dehydrogenase even in 5.0 mg/ml concentration of ICG for 20 minutes with or without light exposure. Conversely, those exposed to ICG and covered with BSS demonstrated a significant decrease of mitochondrial dehydrogenase after incubation in 5, 2.5, and 1.0 mg/ml for 20 minutes in the dark and in 5 to 0.05 mg/ml with light. Clinically, no postoperative staining on RPE was detected. No atrophic RPE changes or other retinal changes were observed in the previous MH area that was covered by autologous whole blood in all 20 eyes on average follow-up of 10.6 months. The hole closed in 19 eyes (95%) on first surgery. Visual acuity improved in 17 eyes (85%) on most recent follow-up. CONCLUSIONS: Whole blood prevents ICG toxicity in RPE cell culture and prevents staining of RPE in surgery of MH when the ILM is stained with ICG.

Adult↗
PubMed2005

Secondary intraocular lens implantation of traumatic cataract in open-globe injury.

BACKGROUND: The purpose of this study was to determine the visual outcome and accuracy of biometry in traumatic cataract in open-globe injury. METHODS: A clinical retrospective study of 30 consecutive patients treated for ocular penetrating trauma was conducted. Patient demographics, causes of injury, wound categories, timing and procedures of the primary repair, interval of subsequent intraocular lens (IOL) implantation, follow-up, and postoperative complications were recorded. Additionally, binocular biometry was documented. Twenty-six eyes (86.7%) were open-globe injuries occurring in the workplace. All patients received cataract extraction with primary repair of the penetrating wound, 18 eyes (60%) underwent trans pars plana vitrectomy with lensectomy and 12 eyes (40%) underwent lens aspiration or extracapsular cataract extraction. Simultaneously, 16 eyes (53.3%) underwent intraocular foreign body removal. RESULTS: The mean visual improvement after secondary IOL implantation was statistically significant (p = 0.002). Seventeen eyes (56.7%) achieved final best-corrected visual acuity of 20/40 or better. The mean deviation of final refraction and target refraction was -0.69 +/- 0.56 diopter, and 23 eyes (76.7%) were within 1 diopter based on biometry of the traumatic eye. In 18 eyes (60%), the difference was within 1 diopter according to biometry of the fellow eye. In 5 cases (16.7%), there was no improvement of vision because of central corneal scar, secondary glaucoma, macular pucker, or recurrent retinal detachment. INTERPRETATION: The vision of patients with traumatic cataract in open-globe injury was improved after prompt surgical intervention and subsequent IOL implantation. A minority of patients experienced no change in vision or a deterioration of vision due to irregular astigmatism caused by a corneal wound or variable damage to the posterior segment. Using biometry of the injured eye after primary repair was more accurate than using biometry of the fellow eye to determine the power of the lens for IOL implantation in variable open-globe injury.

Adolescent↗
PubMed2005

Quantitative grading of preretinal neovascularization in adult rats.

PURPOSE: To quantify photodynamic venous occlusion-induced preretinal neovascularization with fluorescein isothiocyanate-dextran (FITC-dextran) angiography in adult Sprague-Dawley rats. METHODS: Argon green laser was used to ablate retinal veins in the experimental group (24 rats), and applied between the vessels in the control group (10 rats) after systemic injection of rose bengal. Animals were systemically infused with FITC-dextran and killed 14 days after laser treatment. Retinal flat-mounts were observed under a fluorescence microscope. The number and area of neovascular tufts were measured. Confocal microscopy and histological study were performed to rule out possible artifacts, and to confirm FITC-dextran angiography findings. RESULTS: Out of the entire group of 34 albino rats, no preretinal neovascularization was found in the control group (total 20 eyes, 10 rats). In the experimental group (total 48 eyes, 24 rats) 43 eyes (90%) developed well demarcated neovascular tufts revealed by FITC-dextran angiography. This well demarcated boundary of neovascular tufts was reconfirmed by confocal microscopy and histological study. There were no significant differences in the number or area of neovascular tufts between the right and left eyes. CONCLUSION: FITC-dextran angiography provides a time- and labour-efficient basis for quantifying both the number and area of preretinal neovascularization induced by photodynamic venous occlusion in adult rats. This model is suitable for angiostatic study in the adult animals.

Animals↗
PubMed2005

Choroidal detachment after filtering surgery.

BACKGROUND: The purpose of this study is to report the treatment and outcome of eight cases of choroidal detachment, which occurred several days to many years after trabeculectomy. METHODS: This is a retrospective study of eight cases of choroidal detachment after trabeculectomy with or without cataract extraction reviewed at CGMH, Keelung, from 2002 to 2004. One eye with idiopathic scleromalacia with chronic uveitis and secondary glaucoma, five eyes with primary open angle glaucoma and two eyes with chronic angle closure glaucoma after trabeculectomy were reported. Six of the eight cases developed acute onset choroidal detachment within two weeks after surgery. The other two cases suffered from choroidal detachment many years after trabeculectomy for different reasons. Regarding the types of operation, combined glaucoma and cataract surgery was performed in five cases and intraoperative application of adjunctive mitomycin C was used in two cases. Decrease in vision acuity and varying degrees of eye pain with a flat or shallow chamber were noted in all cases. Associated hypotony was found in six of the eight cases. The treatment included topical cycloplegic corticosteroid and oral corticosteroid. RESULTS: Choroidal detachments were improved or complete resolution obtained after medical treatment for about three weeks to one month in all cases. But persistent poor control of intraocular pressure was found in two cases. Ultrasonography was used as a reliable tool to confirm the diagnosis and resolution of choroidal etachment in cases of blurred fundus examination and synechiae miotic pupil. CONCLUSIONS: Choroidal detachment is one of the complications after trabeculectomy. The diagnosis of choroidal detachment can be confirmed most reliably by ultrasonography. Medical therapy is effective for resolution.

Adult↗
PubMed2004

Efficacy and safety of phacoemulsification with intraocular lens implantation under topical anesthesia.

BACKGROUND: To eliminate complications of peribulbar and retrobulbar anesthesia and to achieve efficacy and safety for topical anesthesia with cataract surgery. METHODS: We performed clear corneal phacoemulsification with foldable intraocular lens (IOL) implantation under topical anesthesia using preservative-free 2% lidocaine drops, without intracameral anesthetic supplementation. The exclusion criteria were anxiety, small pupil, baseline endothelial count 1500 cells/mm2, uncontrolled glaucoma, other ocular entities affecting corneal endothelium, and allergy to the relevant medications. We used a specular microscope to evaluate the effect on the endothelium and employed a 10-point visual analog pain scale to assess the discomfort experienced during the operation. RESULTS: Totally, 29 eyes of 29 patients were enrolled in this series. The mean age was 71.5 +/- 8.5 years. Twenty-three of 29 (79.3%) cases achieved a best-corrected visual acuity (BCVA) equal to 20/40 or better at an interval of 3 months postoperatively. Most patients (86.5%) felt mild or no pain during surgery. Pre- and postoperative endothelial counts were 2072.6 +/- 104 and 1927.4 +/- 196 cell/mm2, respectively. One in 29 cases developed vitreous loss due to involuntary eye movements intraoperatively. CONCLUSIONS: Topical anesthesia with preservative-free 2% lidocaine drops is an effective and safe modality for clear corneal phacoemulsification with IOL implantation. On the other hand, for patients with small pupil or those who are anxious, the procedure may be time-consuming, and it is challenging for physicians to perform cataract surgery merely using topical anesthesia.

Aged↗
PubMed2002

Sub-tenon anesthesia for segmental scleral buckling and assessment of postoperative pain.

BACKGROUND: To evaluate the safety and efficacy of sub-Tenon anesthesia for segmental scleral buckling. METHODS: Thirty-two patients diagnosed with rhegmatogenous retinal detachment were treated with segmental scleral buckling under sub-Tenon anesthesia. After topical anesthesia, a buttonhole was made through the conjuntiva and Tenon's capsule 4 mm posterior to the limbus. Four milliliters of anesthetic solution was then delivered into the posterior sub-Tenon space using a blunt cannula. The buckling procedure was done immediately after the completion of anesthesia. We evaluated akinesia and recorded the pain with a visual analogue scale after surgery. RESULTS: There were no anesthesia related complications. Twenty-two patients (69%) reported no pain during surgery. Nine patients (28%) felt pain during surgery. However, the pain was tolerable and the surgeries were finished smoothly with or without a supplemental anesthetic solution. One patient (3%) experienced uncomfortable pain and needed an additional retrobulbar block. Five patients (16%) retained complete eye movement 5 min after anesthesia, and only 4 patients (13%) experienced total akinesia. At the end of the surgery, 16 patients (50%) had total akinesia and 2 patients (6%) retained complete eye movement. CONCLUSIONS: Sub-Tenon anesthesia is efficient and safe in segmental scleral buckling. It can prevent the complications of peribulbar or retrobulbar anesthesia and is a good alternative to both methods of anesthesia, especially in highly myopic eyes.

Adolescent↗
PubMed2002

Cataract extraction in high myopic eyes.

BACKGROUND: According to the high prevalence of myopia in Taiwan, we analyze the adopted cataract extractions, identify predicting factors for postoperative vision, and to assess the incidence of retinal complications after Nd: YAG laser capsulotomy in high myopic eyes. METHODS: One hundred and twenty-five eyes, which the axial lengths were longer than 26 mm, following cataract extraction were enrolled. Surgeries adopted included phacoemulsification with intraocular lens implantation, extracapsular cataract extraction with intraocular lens implantation, phacoemulsification, and extracapsular cataract extraction. Logistic regression was utilized to assess predictive factors for postoperative vision. RESULTS: Postoperative vision of 41 eyes (32.8%) of the 125 high myopic eyes improved at least 4 lines of Snellen acuity. Thirty-two eyes (25.6%) achieved good postoperative vision (BCVA > or = 20/40), and 26 eyes (20.8%) demonstrated poor postoperative vision (BCVA < 20/200). Younger age and shorter axial length were appreciated for better visual outcome (p < 0.05). Nd: YAG laser capsulotomy is required for posterior capsular opacity. Three in 125 eyes (2.4%) developed retinal complications and 2 of them had retinal detachment subsequently within one month after Nd: YAG laser capsulotomy. CONCLUSION: Most high myopic patients achieved visual improvement after cataract surgeries. Age and axial length are the predictive factors in high myopic patients. It is crucial to examine retina prior to Nd: YAG laser capsulotomy to prevent retinal complication.

Adult↗