We studied the change in intraocular pressure (IOP) in 15 consecutive cataract patients who underwent extracapsular cataract extraction and posterior chamber lens implantation between Feb. 1993 and Apr. 1993 to evaluate the effect of this surgery on postoperative IOP. To evaluate the clinical usefulness of non-contact tonometer, the intraocular pressures were measured with Kowa non-contact tonometer (TM-2000, Japan) as well as Goldmann applanation tonometer. There was a decrease in IOP of 3.4±2.9mmHg (p<0.001) 3 months after this surgery and the intraocular pressure differences between pseudophakic eyes and contralateral phakin eyes at 3 months postoperatively were 2.4±3.8mmHg (p<0.05). The correlation coefficient between non-contact tonometer and Goldmann tonometer was 0.8876 (p=0.001) in the postoperative 76 eyes. Therefore, out results suggest that extracapsular cataract extraction and posterior chamber lens implantation alone can be a useful surgical method in cataract patient with ocular hypertension, and non-contact tonometer was relatively accurate in measuring the postoperative intraocular pressure.
Cataract Extraction* ; Cataract* ; Humans ; Intraocular Pressure* ; Methods ; Ocular Hypertension

A retrospective study of 50 consecutive, planned extracapsular cataract extraction with Sheets posterior chamber lens(Model 30LE) inserted in the capsular bag on the outcome between six and twelve months postoperatively, was carried out. Visual improvement of 20/40 or better was obtained in 94.7% as the patients with preexisting ocular pathology were excluded. The postoperative complications consisted of transient iritis in three cases, posterior capsular opacity in one case, and iris capture in one case. The endocapsular cataract extraction with Sheets lens implantation seems to be more safe and effective surgical procedure than any other technique in the case of hypermature cataract.
Cataract Extraction* ; Cataract* ; Humans ; Iris ; Iritis ; Methods ; Pathology ; Postoperative Complications ; Retrospective Studies

PURPOSE: This study was performed to assess efficiency and stability of astigmatic change by incision size after cataract surgery. METHODS: This work was designed as a retrospective, comparative, nonrandomized interventional study. A total of 121 cases of cataract surgery were reviewed in 98 patients performed by one surgeon at the Oregon Eye Institute in Eugene, OR, USA with 3-year follow-ups. All procedures were performed with the temporal approach of self-sealing incisions. The serial change in surgically induced astigmatisms were examined in all cases of three groups: Group A, cartridge injection of a foldable IOL through a 2.5 mm self-sealing incision; Group B, cartridge injection of a foldable IOL through a 3.0 mm self-sealing incision; Group C, cartridge injection of a foldable IOL through a 3.5 mm self-sealing incision. Keratometric data were obtained preoperatively, and 3 weeks, 3 months, 6 months, 9 months, 12 months, 24 months and 36 months postoperatively. Polar value analysis was performed to calculate the surgically induced astigmatism. RESULTS: The astigmatic change decreased over time in Group B (P<0.05). The other groups tended to remain in induced astigmatism. All groups showed anticlockwise torque at 3 weeks following surgery. Group B showed a decrease in deviation, but the other groups showed increases in their torque value at postoperative 12 months (P<0.05). CONCLUSIONS: The 3.0 mm incision size correlated with the least surgically induced astigmatism.
Retrospective Studies ; Phacoemulsification ; Lens Implantation, Intraocular ; Humans ; Cornea/*surgery ; Cataract Extraction/*adverse effects/*methods ; Astigmatism/*etiology

Missing data such as appropriateness ratings in clinical research are a common problem and this often yields a biased result. This paper aims to introduce the multiple imputation method to handle missing data in clinical research and to suggest that the multiple imputation technique can give more accurate estimates than those of a complete-case analysis. The idea of multiple imputation is that each missing value is replaced with more than one plausible value. The appropriateness method was developed as a pragmatic solution to problem of trying to assess "appropriate" surgical and medical procedures for patients. Cataract surgery was selected as one of four procedures that were evaluated as a part of the Clinical Appropriateness Initiative. We created mild to high missing rates of 10%, 30% and 50% and compared the performance of logistic regression in cataract surgery. We treated the coefficients in the original data as true parameters and compared them with the other results. In the mild missing rate (10%), the deviation from the true coefficients was quite small and ignorable. After removing the missing data, the complete-case analysis did not reveal any serious bias. However, as the missing rate increased, the bias was not ignorable and it distorted the result. This simulation study suggests that a multiple imputation technique can give more accurate estimates than those of a complete-case analysis, especially for moderate to high missing rates (30 - 50%). In addition, the multiple imputation technique yields better accuracy than a single imputation technique. Therefore, multiple imputation is useful and efficient for a situation in clinical research where there is large amounts of missing data.
Cataract Extraction/*methods ; Humans ; Logistic Models ; Research Support, Non-U.S. Gov't

Cataract surgery is the commonest ophthalmic surgical procedure and a local anaesthetic technique is usually preferred but the provision of anaesthesia in terms of skills and resources varies worldwide. Intraconal and extraconal blocks using needles are commonly used. The techniques are generally safe but although rare, serious sight- and life-threatening complications have occurred following the inappropriate placement of needles. Sub-Tenon's block was introduced as a safe alternative to needle techniques but complications have arisen following this block as well. Currently, there is no absolutely safe ophthalmic regional block. It is essential that those who are involved in the care of these patients have a thorough knowledge of the techniques used. This review article outlines the relevant anatomy, commonly used techniques and their safe performance and perioperative care.
Cataract Extraction ; Humans ; Nerve Block ; adverse effects ; methods ; Ophthalmologic Surgical Procedures

BACKGROUNDThe TetraFlex accommodating intraocular lens (IOL) was designed to supply the patients both satisfied far and near vision after cataract surgery. So we need to evaluate the safety, distance and near visual acuity, subjective accommodation and IOL mobility with the TetraFlex accommodating IOL implantation.

METHODSFifty eyes of 42 study-eligible cataract patients, who gave informed consent at a single eye clinic in China over a 10-month period, underwent phacoemulsification with TetraFlex IOL implantation. At three months postoperation, uncorrected visual acuities (UCVA), best corrected visual acuities (BCVA), distance-corrected near visual acuities (DCNVA), subjective accommodation using the defocus method, and pilocarpine-induced IOL mobility were measured.

RESULTSNo postoperative complications were noted in the study. Three months postoperation UCVA and BCVA were 20/40 or bettter in 82% (41/50) and 92% (46/50) of eyes, respectively; 66% (33/50) of the eyes had DCNVA of Jager (J) 4 or better at 3 months. In addition, the mean subjective accommodation was (0.94+/-0.61) diopters (D) (range from 0.50 to 1.50 D) and pilocarpine-induced IOL mobility was (337+/-124) microm (range from 121 to 501 microm) with the TetraFlex. High relationship (r2=0.901, P<0.01) was found between these two measurements.

CONCLUSIONImplantation of the TetraFlex is safe and leads to excellent uncorrected distance vision and good uncorrected near vision.

Aged ; Cataract Extraction ; methods ; China ; Female ; Humans ; Lens Implantation, Intraocular ; methods ; Male ; Middle Aged ; Postoperative Complications ; Visual Acuity ; physiology

Internal lenticonus is a very rare morphologic abnormality of crystalline lens which has been reported in only several cases in the literature. We herein reported the clinical characteristics and surgical findings of the anterior internal lenticonus accompanied by congenital nuclear cataract. Cataract extraction accompanied with intraocular lens implantation was uneventfully performed, and a good visual outcome was achieved in this case. Viral infection during embryonal and fetal period might account for the formation of the anterior internal lenticonus and congenital nuclear cataract in our case.
Cataract Extraction ; methods ; Humans ; Lens Diseases ; surgery ; Lens Implantation, Intraocular ; methods ; Lens, Crystalline ; abnormalities ; surgery ; Male ; Middle Aged ; Visual Acuity

PURPOSE: To assess the risk factors for endothelial cell loss after phacoemulsification with implantation of intraocular lens according to anterior chamber depth (ACD). METHODS: This prospective study included 94 eyes of 94 patients undergoing phacoemulsification cataract surgery. To assess the risk factors for corneal endothelial cell loss, we examined seven variables at 1 day, 1 week, 6 weeks, and 12 weeks postoperatively in each ACD-stratified group. RESULTS: Multiple linear regression analysis showed that the only variable influencing the percentage decrease in corneal endothelial cell density throughout the postoperative follow-up period in the long ACD group (ACD III) was nucleosclerosis. The variables influencing the percentage decrease in corneal endothelial cell density in the short ACD group (ACD I) at one day and one week postoperatively were corneal incisional tunnel length and nucleosclerosis. CONCLUSIONS: Risk factors for endothelial cell loss after phaoemulsification were different according to ACD. Long corneal tunnel length can be one of the risk factors for endothelial cell loss in short ACD eyes.
Anterior Chamber/ultrasonography ; Cataract/ultrasonography ; Cataract Extraction/*methods ; Cornea/pathology/surgery ; Corneal Endothelial Cell Loss/*etiology ; Humans ; Lens Implantation, Intraocular ; Phacoemulsification/*adverse effects/methods ; Prospective Studies ; Risk Factors

With the advent of modern surgical techniques, paediatric cataract has become much more manageable. Intraocular lens (IOL) implantation is the standard of care for patients over the age of 2 years. The use of IOL in young infants is still controversial. In addition, there are still unresolved issues, such as the minimum age at which IOL can be safely implanted, IOL power selection and IOL power calculation. The current trends in the management of the above challenges are discussed. Although numerous reports on the prevention and management of posterior capsule opacification have been published, there are ongoing intensive debates and research. Long-term postoperative complications like glaucoma and rhegmatogenous retinal detachment are problems that cannot be overemphasised and these issues are also reviewed.
Cataract ; congenital ; Cataract Extraction ; adverse effects ; methods ; Child ; Child, Preschool ; Humans ; Infant ; Infant, Newborn ; Lens Implantation, Intraocular ; adverse effects ; methods ; Lenses, Intraocular ; Postoperative Complications ; prevention & control ; Refraction, Ocular

PURPOSE: To evaluate the factors that affect postoperative astigmatism and post-suture removal astigmatism, and to evaluate the risk factors associated with astigmatism axis shift. METHODS: We performed a retrospective chart review of 130 eyes that had undergone uneventful phacoemulsification cataract surgery. Preoperative astigmatism was divided into four groups (Groups I, II, III, and IV) according to the differences between the axis of preoperative astigmatism (flattest axis) and the incision axis (105 degrees). We analyzed the magnitude and axis of the induced astigmatism after the operation and after suture removal in each group. We also analyzed the factors which affected the postoperative astigmatism and post-suture removal astigmatism in each sub-group of Groups I, II, III, and IV, excluding postoperative or post-suture removal axis shift (specifically, Group I(WAS), II(WAS), III(WAS), and IV(WAS)). We identified the variables associated with the prevalence of postoperative astigmatism axis shift and those associated with the prevalence of post-suture removal axis shift. RESULTS: An increase in the magnitude of postoperative astigmatism was associated with an increase in the preoperative magnitude of astigmatism in Groups I(WAS), II(WAS), and III(WAS) (p<0.05), and with an increase in the corneal tunnel length in Group I(WAS). A decrease in the magnitude of postoperative astigmatism was associated with an increase in the corneal tunnel length in Groups III(WAS) and IV(WAS) (p<0.05). An increase in the magnitude of post-suture removal astigmatism was associated with an increase in the magnitude of postoperative astigmatism in Groups I(WAS) and IV(WAS) (p<0.05), and with late suture removal in Group IV(WAS) (p<0.05). A decrease in the magnitude of post-suture removal astigmatism was associated with late suture removal in Groups I(WAS) and II(WAS). A logistic regression analysis showed that the prevalence of post-suture removal astigmatism axis shift was associated with increased corneal tunnel length, decreased magnitude of postoperative astigmatism, and early suture removal. CONCLUSIONS: In order to reduce postoperative and post-suture removal astigmatism, we recommend a short corneal tunnel length and late suture removal in patients with Group I(WAS) characteristics, late suture removal in Group II(WAS)-like patients, long corneal tunnel length in Group III(WAS)-like patients, and long corneal tunnel length and early suture removal in patients with characteristics of Group IV(WAS).
Astigmatism/etiology/*prevention & control ; Cataract Extraction/*methods ; Follow-Up Studies ; Humans ; Postoperative Complications/etiology/prevention & control ; Retrospective Studies ; *Suture Techniques