人工晶体植入术后复视

目的:本文报道7例人工晶体植入术后复视病例,并初步探讨其原因及预防。方法:随访60例单侧白内障摘除及人工晶体植入术连续病例。复视病例,检查复视类型、眼位、眼球活动度、屈光状态、瞳孔及眼底,并散瞳检查人工晶体位置。结果:本文报告白内障摘除及人工晶体植入术后复视发生率为11.67％。术前存在斜视,双眼融合功能障碍,局麻药物对眼外肌的毒性作用,人工晶体中心偏移,黄斑部病变及晶体后囊不均匀混浊等与术后复视有关。结论:复视是白内障摘除及人工晶体植入术后一个重要的并发症。其治疗往往较困难,根据复视的可能原因,采取预防措施对减少术后复视有帮助。眼科学报1997;13:210—212。     

膜性白内障人工晶体植入术

本文报道１９例外伤或手术后膜性白内障行后房型人工晶体植入联合囊膜切开术或Ｎｄ：ＹＡＧ激光囊膜切开，收到较好的效果，１２例视力≥０．３，９例≥０．５。对手术及ＹＡＧ激光治疗的并发症及预防措施作简要论述。     

Lens opacity in patients with hypercholesterolemia and ischaemic heart disease

Lens opacity studies were performed using an electronic Lens Opacity Meter (Interzeag Opacity Lensmeter 701) in a population (n = 321) with ischaemic heart disease. These patients are participating in a trial targetting at the reduction of mortality and incidence of myocardial infarction using a cholesterol-lowering drug, simvastatin. A separate study to evaluate the reliability of the method showed good reproducibility. Repeated measurements after a short time-interval (2–10 days) gave statistically lower opacity values either due to a change in lens transparency or perhaps a change in pigment and cell dispersion in the acqueous caused by repeated mydriasis. Lens opacity values showed a highly significant positive correlation to age. Serum cholesterol, systolic blood pressure and smoking habits showed no significant correlations to the levels of lens opacity when adjustments for age were made.Abbreviations HMG-CoA hydroxy-methylglutarylcoenzyme A - 4S Scandinavian Simvastatin Survival Study - LOM lens opacity meter     

The spherical aberration of aphakic eyes corrected with intra-ocular lenses

The spherical aberration of eyes corrected with intra-ocular lenses is investigated using a model eye with realistic levels of corneal asphericity. The results indicate that the aberration is intermediate between that of paraxial schematic eyes and real eyes. By using standard optical aberration theory, it is shown that for a plano-convex lens with the curved surface facing the cornea, the aberration is similar to that of normal phakic eyes and therefore probably too low to be of any clinical significance. However, for other lens orientations or designs, the level of aberration is usually higher and may lead to a refractive error varying with pupil size and a loss of acuity with large pupil diameters.     

Apoptosis of bile duct epithelial cells in hepatic allograft rejection

Liver biopsy remains the 'gold standard' for monitoring rejection in liver transplant patients. Portal inflammation, bile duct damage and endothelialitis are recognized features of hepatic allograft rejection. The pathogenesis of the bile duct injury during rejection, however, remains unclear. To define the mechanism of bile duct damage, we studied the light- and electronmicroscopic appearance of hepatic tissue from selected patients in whom allograft failure was solely due to rejection. Of the 25 orthotopic liver transplant rejection cases examined, 17 were mild, seven were moderate and one was severe rejection. Light microscopy examination of the damaged bile duct epithelium revealed evidence of apoptosis which was confirmed by electronmicroscopy. Furthermore, there appeared to be a positive correlation between the grade of rejection and the number of apoptotic cells. Also included in the study were 13 cases of chronic active hepatitis and 10 normal livers which showed the least apoptotic cells. We conclude that the identification of apoptotic cells in damaged bile ducts in allograft biopsies might be helpful in the diagnosis of rejection and in assessment of the severity of rejection.     

Cloning and expression of SLC1OA4,a putative organic anion transport protein

AIM:To determine if novel bile acid transporters may be expressed in human tissues.METHODS:SLC10A1 (NTCP) was used as a probe to search the NCBI database for homology to previously uncharacterized ESTs. The homology search identified an EST (termed SLC10A4) that shares sequence identity with SLC10A1 and SLC10A2 (ASBT). We performed Northern blot analysis and RT-PCR to determine the tissue distribution of SLC10A4. SLC10A4 was cloned in frame with an epitope tag and overexpressed in CHO cells to determine cellular localization and functional analysis of bile acid uptake.RESULTS:Northern analysis revealed that SLC 10A4 mRNA is ubiquitously expressed fn human tissues with the highest levels of mRNA expression in brain,placenta, and liver. In SLC10A4-transfected CHO cells,immunoblotting analysis and immunofluorescence staining demonstrated a 49-kDa protein that is expressed at the plasma membrane and intracellular compartments.Functional analysis of SLC10A4 showed no significant taurocholate uptake in the presence of sodium when compared to untransfected CHO cells.CONCLUSION:To date, we have shown that this protein has no capacity to transport taurocholate relative to SLC1041; however, given its ubiquitous tissue distribution, it may play a more active role in transporting other endogenous organic anions.     

微囊化猪视网膜色素上皮细胞移植治疗帕金森病的实验研究(英文)

目的研究微囊化后的猪视网膜色素上皮细胞(retinal pigment epithelial,RPE)对帕金森病大鼠模型的移植疗效。方法原代培养RPE 并传代,高效液相色谱法测定培养液上清中多巴胺(dopamine, DA)和高香草酸(homovanillic acid, HVA)的含量,ELISA法检测脑源性神经营养因子(brain-derived neurotrophic factor, BDNF)和胶质细胞源性神经营养因子(glial-derived neurotrophic factor, GDNF)的含量。用高压静电成囊装置制备海藻酸钠-多聚赖氨酸-海藻酸钠微囊化细胞。6-羟基多巴胺(6-hydroxydopamine, 6-OHDA)毁损内侧前脑束 (medial fore-brain bundle,MFB)建立 SD 大鼠帕金森病模型。立体定向移植 RPE+ 微囊,检验旋转实验、免疫组化和脑内生化的变化。结果 RPE 培养上清液中DA、HVA、BDNF、GDNF 的含量稳定,微囊化后细胞长期存活,活性没有明显变化。6-OHDA毁损MFB建立大鼠帕金森病模型的成模率为83%。移植微囊化的RPE后有效率为33%。结论猪 RPE 体外培养生长旺盛,持续分泌 DA、BDNF 和 GNDF,微囊化不影响其分泌功能。RPE 移植对帕金森病大鼠有一定的治疗作用。     

Cardinal points and image–object magnification with an accommodative lens implant (1 CU)

A simple mathematical method for the determination of the cardinal points of pseudophakic eyes after implantation of an accommodative intraocular lens [posterior chamber intraocular lenses (PCIOL)] is presented. The purpose of this study was to explore the changes during pseudophakic accommodation (PAC) in (1). the positions of the cardinal points, (2). the distance of the object conjugate with the retina, and (3). the image-object magnification. These theoretical accommodation data are compared with clinical measurements. METHODS AND PATIENTS: Using biometrical measurements of the axial length, equivalent power of the cornea and the anterior chamber depth (ACD) in the non-accommodated state we used linear geometric optics for determination of the cardinal points and object distance as well as lateral magnification (the ratio of image to object size). With the measurement of ACD decrease (following pharmacological stimulation of the ciliary muscle with 2% pilocarpine eye drops) we determined the changes of the cardinal points and magnification to assess PAC amplitude from the shortening of the object distance. Calculated values of PAC amplitude were compared with the respective measured values derived from amplitude measures by accommodometer, defocusing and streak retinoscopy. We analysed the results of a prospective study on 35 eyes of 28 patients after cataract surgery (target refraction: -0.2 D) and accommodative PCIOL implantation (1 CU, Human Optics AG, Erlangen, Germany) 3 months after surgery. RESULTS: After pilocarpine eye drops, ACD (mean +/- S.D., range; median) decreased by 0.88 +/- 0.48 mm (0.51-1.91; 0.66). Distance of the in-focus object decreased from the non-accommodated state (-5.62 +/- 1.83 m, -25 to -1.1; -4.83 m) to the accommodated state (ACD decrease) (-0.81 +/- 0.21, -2.11 to -0.65; -0.79 m). For a theoretical ACD decrease of 1.0 mm (the intrinsic limitation of the PCIOL design) it was -0.59 +/- 0.28, -1.31 to -0.51; -0.63 m and resulted in an objective accommodative response of 1.49 +/- 0.16, 1.21-1.81; 1.46 D, depending on the actual geometry of the individual eye. On average, magnification as induced by PAC in contrast to that induced by adequate spectacle addition differed by only about 1%. Accommodation measured with defocusing and the accommodometer correlated significantly with the theoretical value based on IOLMaster measurement of ACD decrease (r = 0.752, p = 0.005 and r = 0.676, p = 0.02). Likewise, accommodation measured with streak retinoscopy correlated weakly with the theoretical value based on IOLMaster ACD decrease (r = 0.465, p = 0.05). CONCLUSIONS: Using geometrical optics, PAC can be derived from the biometric data of the eye and the measured ACD decrease. This approach may be an additional indicator for the accommodative response in pseudophakic patients and may allow a subdivision of the measured accommodation into true PAC and pseudoaccommodation, for example, because of increased depth of focus induced by pupillary constriction.     

Legal issues in contact lens practice with special reference to the practice of orthokeratology

This report aims to encourage optometrists to reflect on the legal implications of clinical contact lens practice, with particular reference to the practice of orthokeratology (ortho-k), which has seen a recent revival of interest. A patient may claim compensation if an optometrist is negligent by breaching his duty to exercise reasonable care and skill in diagnosis, advice or treatment. However, the optometrist will only be liable for reasonably foreseeable harm to the patient, so practitioners need to be fully aware of the foreseeable risks. Failure to adequately inform the patient may lead to a claim for negligence, if disclosure of the risks would have influenced the patient's decision to undergo or forego the procedure. It is important that the professional bodies establish guidelines on acceptable practice, with particular emphasis on the provision of information to patients. Reasonable disclosure, use of appropriate information/consent forms, and proper documentation of cases, should all focus on the needs of, and benefits to, patients.