角膜屈光手术后屈光回退的手术治疗进展*

屈光回退是角膜屈光手术后的并发症之一,其治疗方法主要为药物治疗和手术治疗。对于需要再次手术的患者,应根据初次手术方式、距离初次手术时间、回退度数,在充分评价角膜情况后合理选择增效术,确保手术的安全性和有效性。目前,准分子激光原位角膜磨镶术和飞秒激光小切口角膜基质透镜取出术是治疗近视和近视散光的主要手术方式。本文就两者术后屈光回退手术治疗的适应症、不同增效术的优缺点及注意事项作一综述。     

Otoplasty: the experience of 100 consecutive patients

Although prominent ears are the most common congenital deformity in the head and neck region, only approximately 8 percent of patients who present for treatment of this deformity will have some family history of the abnormality. More than 200 techniques have been described for correction of this deformity, indicating that there is no single widely accepted procedure that has been adopted by most surgeons. The authors of this study present their choice of a procedure that combines the most beneficial features of three previously described techniques and that provides consistently satisfactory results.The surgical technique consists of scoring of the antihelical cartilage on its anterior surface in a subcutaneous position (as described by Stenstrom), suturing to recreate the fold of the antihelix (in the fashion of Mustarde), and concha-mastoid suturing applied to the back of the ear to decrease the concha-scaphoid angle (in the manner of Furnas). The last 100 consecutive patients operated on by the senior author (J.A.F.) over a 10-year period were evaluated. Follow-up data were analyzed using the Kaplan-Meier survival method. The postoperative analysis focused on the incidence of postoperative complications and the overall results of the technique.Most operations were performed bilaterally, on women, and with the patient under local anesthesia. There were few complications, and the incidence of complications was much lower than had been noted in previously reported series. All patients were very satisfied with the improvement in the appearance of their ears.The combined technique presented is safe, easy to perform, and has few complications, and its final outcome is reproducible and long-lasting. It can be considered a standard technique to be used for treating patients of any age and with any magnitude of defect.     

Refractive Errors Affect the Vividness of Visual Mental Images

The hypothesis that visual perception and mental imagery are equivalent has never been explored in individuals with vision defects not preventing the visual perception of the world, such as refractive errors. Refractive error (i.e., myopia, hyperopia or astigmatism) is a condition where the refracting system of the eye fails to focus objects sharply on the retina. As a consequence refractive errors cause blurred vision.We subdivided 84 individuals according to their spherical equivalent refraction into Emmetropes (control individuals without refractive errors) and Ametropes (individuals with refractive errors). Participants performed a vividness task and completed a questionnaire that explored their cognitive style of thinking before their vision was checked by an ophthalmologist. Although results showed that Ametropes had less vivid mental images than Emmetropes this did not affect the development of their cognitive style of thinking; in fact, Ametropes were able to use both verbal and visual strategies to acquire and retrieve information. Present data are consistent with the hypothesis of equivalence between imagery and perception.     

Surgical alternatives in the treatment of hepatic hydatidosis]

Echinococcosis is an endemic zoonosis in the south of Chile, so we have the opportunity to treat many patients especially the liver location which is the most common situation of this disease. Hepatic hydatid cyst presents its own morbidity and mortality due its complications and associated with surgical procedures. Morbidity has rates between 11 and 86% and is related with previous surgical interventions, cysts complications, the necessity of perform additional procedures during surgery and the treatment of other disease locations. Mortality by otherwise has rates below 5%. But both, morbidity and mortality persist high in spite of technological advances and therapeutical improvement. The surgical treatment of hepatic hydatidosis can be divided in four phases: surgical area isolation, cysts evacuation, treatment of cyst complications (biliary tract rupture, hepatothoracic transit, etc.), and residual cavity treatment. For each one exist different alternatives. On the other hand, hydatid cyst surgery can be classified in conservative and resective procedures. In the first group we consider marsupialization, cystostomy, Knowsly or Posadas operation and cystojejunostomy. In the resective group we include pericystectomy, partial or subtotal cystectomy and the different types of hepatectomies. Finally, some other surgical procedures are under evaluation. These include the laparoscopic approach of liver echinoccosis with few studies in the field, but with hopeful results.     

Iodine-125 Seed Implantation in the Treatment of Sacrococcygeal Chordoma: A Case Report

The objective of this was to summarize the efficacy and safety of iodine-125 seed implantation in the treatment of sacrococcygeal chordoma. CT-guided implantation of radioactive iodine-125 seed was applied in treating a patient with sacrococcygeal chordoma. The incidence of complications was recorded and the results were evaluated and analyzed, to compare the postoperative complications and recurrence rate of sacrococcygeal chordoma. The patient was followed up to 15 months after operation. The minimum peripheral dose was 180?Gy, and 8?months after the implantation, the tumor mass was reduced significantly. There was no serious complications detected during the follow-up period. Radioactive iodine-125 seed implantation can improve the target volume dose, with the high doses of radioactive iodine-125 seed, the tumor, which was refractory and insensitive to chemotherapy and radiotherapy, can be effectively controlled and complications are less than surgical treatment. However, the long-term efficacy of this treatment needs further follow-up.     

PULMONARY OPERATIONS IN EMPHYSEMATOUS PATIENTS

Although emphysema itself is a disease of the entire lungs and so is not amenable to surgical therapy, there are many conditions in emphysematous patients in which surgical operation can be quite helpful—for example, some complications of emphysema and some conditions not etiologically related to emphysema but affecting the lungs. Among these conditions are infectious diseases (pneumonia, bronchiectasis, tuberculosis and infected bullae) and other conditions such as spontaneous pneumothorax, the presence of space-occupying bullae and carcinoma.The surgical treatment required may range from suction or drainage to wide resection.     

A 63 element 1.75 dimensional ultrasound phased array for the treatment of benign prostatic hyperplasia

Background  

Prostate cancer and benign prostatic hyperplasia are very common diseases in older American men, thus having a reliable treatment modality for both diseases is of great importance. The currently used treating options, mainly surgical ones, have numerous complications, which include the many side effects that accompany such procedures, besides the invasive nature of such techniques. Focused ultrasound is a relatively new treating modality that is showing promising results in treating prostate cancer and benign prostatic hyperplasia. Thus this technique is gaining more attention in the past decade as a non-invasive method to treat both diseases.     

Neurotrophic factors for the treatment of Parkinson's disease

Parkinson's disease (PD) is a common neurodegenerative disorder caused by the progressive degeneration of the nigrostriatal dopaminergic pathway. The resulting loss of dopamine neurotransmission is responsible for the symptoms of the disease. Available treatments are initially successful in treating PD symptoms; however, their long-term use is associated with complications and they cannot stop the neurodegeneration. Current research aims at developing new therapies to halt/reverse the neurodegenerative process, rather than treating symptoms. Neurotrophic factors are proteins critical for maintenance and protection of neurones in the developing and adult brain. Several neurotrophic factors have been investigated for their protective effects on dopaminergic neurones. Here we review some of the most promising factors and provide an update on their status in clinical trials.     

Complications in surgery: root cause analysis and preventive measures

Patients expect to receive quality medical care by relying on the concepts of evidence-based medicine. This quality care is expected to be provided at decreased costs for payors, some of whom have stopped reimbursement for cases involving "reasonably preventable" surgical complications. The purpose of this article is to introduce root cause analysis as a tool for identifying the causes of surgical complications. The authors also discuss preventive measures, such as improved communication, checklists, reporting systems, and the use of evidence-based medicine, that have been implemented to decrease surgical complications. These preventive measures can be used alone or together to decrease complications and improve overall patient care.     

Reversible Femtosecond Laser-Assisted Myopia Correction: A Non-Human Primate Study of Lenticule Re-Implantation after Refractive Lenticule Extraction

LASIK (laser-assisted in situ keratomileusis) is a common laser refractive procedure for myopia and astigmatism, involving permanent removal of anterior corneal stromal tissue by excimer ablation beneath a hinged flap. Correction of refractive error is achieved by the resulting change in the curvature of the cornea and is limited by central corneal thickness, as a thin residual stromal bed may result in biomechanical instability of the cornea. A recently developed alternative to LASIK called Refractive Lenticule Extraction (ReLEx) utilizes solely a femtosecond laser (FSL) to incise an intrastromal refractive lenticule (RL), which results in reshaping the corneal curvature and correcting the myopia and/or astigmatism. As the RL is extracted intact in the ReLEx, we hypothesized that it could be cryopreserved and re-implanted at a later date to restore corneal stromal volume, in the event of keratectasia, making ReLEx a potentially reversible procedure, unlike LASIK. In this study, we re-implanted cryopreserved RLs in a non-human primate model of ReLEx. Mild intrastromal haze, noted during the first 2 weeks after re-implantation, subsided after 8 weeks. Refractive parameters including corneal thickness, anterior curvature and refractive error indices were restored to near pre-operative values after the re-implantation. Immunohistochemistry revealed no myofibroblast formation or abnormal collagen type I expression after 8 weeks, and a significant attenuation of fibronectin and tenascin expression from week 8 to 16 after re-implantation. In addition, keratocyte re-population could be found along the implanted RL interfaces. Our findings suggest that RL cryopreservation and re-implantation after ReLEx appears feasible, suggesting the possibility of potential reversibility of the procedure, and possible future uses of RLs in treating other corneal disorders and refractive errors.     

Refractive Errors in 3–6 Year-Old Chinese Children: A Very Low Prevalence of Myopia?

Purpose

To examine the prevalence of refractive errors in children aged 3–6 years in China.

Methods

Children were recruited for a trial of a home-based amblyopia screening kit in Guangzhou preschools, during which cycloplegic refractions were measured in both eyes of 2480 children. Cycloplegic refraction (from 3 to 4 drops of 1% cyclopentolate to ensure abolition of the light reflex) was measured by both autorefraction and retinoscopy. Refractive errors were defined as followed: myopia (at least −0.50 D in the worse eye), hyperopia (at least +2.00 D in the worse eye) and astigmatism (at least 1.50 D in the worse eye). Different definitions, as specified in the text, were also used to facilitate comparison with other studies.

Results

The mean spherical equivalent refractive error was at least +1.22 D for all ages and both genders. The prevalence of myopia for any definition at any age was at most 2.5%, and lower in most cases. In contrast, the prevalence of hyperopia was generally over 20%, and declined slightly with age. The prevalence of astigmatism was between 6% and 11%. There was very little change in refractive error with age over this age range.

Conclusions

Previous reports of less hyperopic mean spherical equivalent refractive error, and more myopia and less hyperopia in children of this age may be due to problems with achieving adequate cycloplegia in children with dark irises. Using up to 4 drops of 1% cyclopentolate may be necessary to accurately measure refractive error in paediatric studies of such children. Our results suggest that children from all ethnic groups may follow a similar pattern of early refractive development, with little myopia and a hyperopic mean spherical equivalent over +1.00 D up to the age of 5–6 yearsin most conditions.     

Protein molecular weight computation from sedimentation velocity data

In ultracentrifugation, the concentration gradient of mono-disperse samples obtained by sedimentation velocity experiments is described by Gehatia's equation which holds several parameters including the sedimentation and diffusion constants. Once these two constants are known, the molecular weight follows from the Svedberg equation. A least squares method has been developed to derive the transport constants from the refractive index gradient curves. The method employs a mathematical model based on Gehatia's theory. A main feature of the model is the application of two sets of intermediate parameters via which the transport coefficients are much casier calculated than along a direct way. Furthermore some difficult to observe quantities cancel out. The square residues are minimised numerically. The potential errors introduced by this numerical minimalisation are shown to be unimportant compared to the unavoidable experimental errors.     

Radiation treatment for refractory endometriosis: a 38-year-old female presenting with vaginal bleeding

BackgroundEndometriosis is typically managed with a medical or surgical approach, though some patients have medically refractory disease and are poor surgical candidates.Case presentationA 39-year-old woman presented to our facility with uncontrolled bleeding and pain from an endometriotic mass at the vaginal cuff. She had a history of abdominal hysterectomy with bilateral salpingo-oophorectomy, now with medically refractive and inoperable disease due to prior history of vesicovaginal fistula. We prescribed 30 Gy in 10 fractions with 10 MV and 18 MV photons to the target. At follow-up our patient reported a complete resolution of bleeding and pelvic pain.ConclusionRadiation treatment can be an effective treatment for refractory endometriosis.     

准分子激光眼科治疗机中激光器控制实现

准分子激光眼科治疗机可以用来进行近视、远视、散光等屈光不正的矫正手术。其中激光器的控制为手术提供能量稳定的激光脉冲,是对手术安全性、可靠性的重要保证。本文简述了一准分子激光眼科治疗机的整体组成部分,并详细描述了激光器的控制部分:计算机与激光器的通信控制、激光发射停止控制、充换气流程控制。目前,这种准分子激光治疗机已经应用于临床,并取得了良好的效果。     

Dupuytren's Contracture of the Fingers—A Simplified Approach to Surgical Treatment

Hematoma formation, delay in healing, pain, stiffened finger joints are complications that sometimes follow classical surgical approaches to Dupuytren''s contracture. A new surgical approach to the disease that can correct the contractures without the attendant morbidity is urgently needed. By treating Dupuytren''s as any other scar contracture (division of the contracting soft tissue at its point of maximal tension and interposing normal free full-thickness skin) postoperative morbidity can be greatly decreased. Full return of function was achieved within 21 days following operation in 85 percent of the cases in which finger contractures were present before operation. Contracture release of 100 joints was done by this means, with loss of only one graft and without recurrence of the disease. This technique offers simple surgical control of progressive and recurrent Dupuytren''s contracture of the fingers with minimal postoperative morbidity.     

Current uses of ophthalmic lasers.

Current laser treatments are quick, relatively painless, and well tolerated. Some ophthalmic techniques can be performed only by laser while others have a lower morbidity than alternative treatments. Peripheral retinal photocoagulation and focal photocoagulation now offer greatly improved visual prognosis for diabetic patients with proliferative diabetic retinopathy or diabetic macular disease. Selected cases of macular degeneration may be treated by focal laser photocoagulation. The role of lasers in treating sub-retinal neovascular membranes is limited by the extent and location of the membrane at presentation and the high risk of recurrence after treatment. Patients with distorted vision must be referred urgently for specialist ophthalmic assessment. Flat retinal holes and tears may be sealed by laser therapy, thus preventing retinal detachment. Short pulsed neodymium-YAG photodisruptive capsulotomy effectively clears the visual axis of thickened posterior lens capsule after cataract surgery. Short pulsed neodymium-YAG photodisruptive iridotomy may be used to treat and prevent angle closure glaucoma. Laser trabeculoplasty aids the control of open angle glaucoma. Research is continuing into the role of other lasers in managing open angle glaucoma and of photoablative lasers in treating refractive errors and superficial corneal disorders.     

股骨近端抗旋髓内钉法治疗老年股骨转子下粉碎性骨折的效果分析

目的:探讨利用股骨近端抗旋髓内钉法治疗老年股骨转子下粉碎性骨折的临床效果,为临床提供参考。方法:对我院2009年6月-2013年1月收治的38例老年股骨转子下粉碎性骨折患者行股骨近端抗旋髓内钉法进行手术治疗,分析手术方法、效果及患者的预后效果。结果:28例行闭合复位,7例行骨折端切开复位,患者术后7-14d可下地活动,3 m内扶拐部分负重行走,31例(88.6%)获得随访,随访时间9-24个月,骨折愈合时间为3-6个月,平均3.7个月;Harris髋功能评分标准:优18例,良10例,中3例,优良率90.32%(28/31)。结论:PFNA是一种治疗老年股骨转子下粉碎性骨折的有效装置,能够减少骨折不愈合、髋内翻畸形愈合及内固定断裂、切割股骨头等并发症,在治疗老年股骨转子下粉碎性骨折时可达到较高的骨愈合率、较快的功能恢复。     

近视的药物治疗及手术治疗研究进展

近视是最常见的眼病之一,近年来,由于近视的发病率逐年上升,已成为世界性医学问题,近视眼的治疗也成为研究重点。药物研究和手术治疗是近视的治疗目前的研究热点,并已经取得一定得成果。药物方面,阿托品,托品酰胺,哌仑西平,消旋山莨菪碱对近视的控制作用都有被证实,但由于应用上还有一定的副作用,远期效果也不明确,需要进一步研究。手术方面,近视眼手术主要分为角膜屈光手术和眼内屈光手术。LASIK手术是目前应用最广泛的角膜屈光手术方法,SBK手术,飞秒激光手术等技术也日趋成熟。但是,角膜手术存在着一定的风险,应用范围也较为局限,需要进一步研究。眼内屈光手术主要为有晶体眼的人工晶体植入术(PIOL)和屈光性晶状体置换术,矫正的范围更加大,但是眼内手术并发症较多,也需要进一步研究和改进。     

Systematic errors in isothermal titration calorimetry: Concentrations and baselines

In the study of 1:1 binding by isothermal titration calorimetry, reagent concentration errors are fully absorbed in the data analysis, giving incorrect values for the key parameters—K, ΔH, and n—with no effect on the least-squares statistics. Reanalysis of results from an interlaboratory study of a selected biochemical process demonstrates that concentration errors are likely responsible for most of the overall statistical error in these parameters. The concentration errors are approximately 10%, greatly exceeding expected levels. Furthermore, examination of selected data sets reveals a surprising sensitivity to the baseline, suggesting a need for great care in treating dilution heats.