A comparison of forward and inverse treatment planning for intensity-modulated radiotherapy of head and neck cancer.

BACKGROUND AND PURPOSE: To compare intensity-modulated treatment plans of patients with head and neck cancer generated by forward and inverse planning. MATERIALS AND METHODS: Ten intensity-modulated treatment plans, planned and treated with a step&shoot technique using a forward planning approach, were retrospectively re-planned with an inverse planning algorithm. For this purpose, two strategies were applied. First, inverse planning was performed with the same beam directions as forward planning. In addition, nine equidistant, coplanar incidences were used. The main objective of the optimisation process was the sparing of the parotid glands beside an adequate treatment of the planning target volume (PTV). Inverse planning was performed both with pencil beam and Monte Carlo dose computation to investigate the influence of dose computation on the result of the optimisation. RESULTS: In most cases, both inverse planning strategies managed to improve the treatment plans distinctly due to a better target coverage, a better sparing of the parotid glands or both. A reduction of the mean dose by 3-11Gy for at least one of the parotid glands could be achieved for most of the patients. For three patients, inverse planning allowed to spare a parotid gland that had to be sacrificed by forward planning. Inverse planning increased the number of segments compared to forward planning by a factor of about 3; from 9-15 to 27-46. No significant differences for PTV and parotid glands between both inverse planning approaches were found. Also, the use of Monte Carlo instead of pencil beam dose computation did not influence the results significantly. CONCLUSION: The results demonstrate the potential of inverse planning to improve intensity-modulated treatment plans for head and neck cases compared to forward planning while retaining clinical utility in terms of treatment time and quality assurance.     

Treatment of localized prostate cancer using a combination of high dose rate Iridium‐192 brachytherapy and external beam irradiation: Initial Australian experience

Combination high dose rate brachytherapy (HDRB) and external beam radiation therapy is technically and clinically feasible as definitive treatment for localized prostate cancer. We report the first large Australian experience using this technique of radiation dose escalation in 82 patients with intermediate‐ and high‐risk disease. With a median follow up of 3 years (156 weeks), complications were low and overall prostate‐specific antigen progression‐free survival was 91% using the American Society for Therapeutic Radiology and Oncology consensus definition. The delivery of hypofractionated radiation through the HDRB component shortens overall treatment time and is both biologically and logistically advantageous. As a radiation boost strategy, HDRB is easy to learn and could be introduced into most facilities with brachytherapy capability.     

Fifty years of plastic surgery in the Netherlands. VI. Microsurgery

Use of the operating microscope created many new possibilities in plastic, reconstructive and hand surgery. Initially most work was done in digital replantation and, somewhat later, in transfers of toes for reconstruction of amputated thumbs. Microvascular surgery, however, appeared to be a technique suitable for more applications. Anatomical research of the blood supply of skin, fascia, muscle and bone identified flaps that could be carried by pedicle vessels. Transfer of these flaps and revascularization by microvascular anastomoses of the pedicle vessels set the stage for free flaps. In a few decades microsurgical techniques in plastic surgery fully matured. With free flap surgery single-stage and complex reconstructions could be achieved leading to earlier mobilization and better restoration of function with a shorter hospital stay. Today, microvascular free tissue transfer is an essential part of plastic and reconstructive surgery. Further advances in microsurgery and free tissue transfers deserve to be mentioned: pre-fabrication of free flaps, reduction of donor site morbidity, development of artificial conduits and instrumentation and finally homologous transplantations.     

Tyrosinämie Typ I

Tyrosinemia type I is an autosomal recessive inherited defect of tyrosine metabolism. The underlying cause is a defect of fumarylacetoacetate hydrolase. The disease affects the liver (acute liver failure, liver cirrhosis, hepatocellular cancer), the kidney (tubulopathy with hypophosphatemic rickets), and the peripheral nervous system (paresthesia, vegetative symptoms, progressive paralysis). Beside the hypertyrosinemia the diagnosis can be made on the basis of urinary excretion of a pathological metabolite of the tyrosine metabolism (succinylacetone). Therapeutic options are a regulated phenylalanine/tyrosine diet, a very effective drug therapy (NTBC) that has been available for several years, and in cases of acute liver failure or end-stage liver cirrhosis a liver transplantation.     

Lactobacillus bei Schwangeren

Ohne Zusammenfassung     

Fetofetales Transfusionssyndrom

In monochorionic twin pregnancies, the risk of developing a twin to twin transfusion syndrome is between 15 and 20%. Using high-resolution ultrasound machines, sonographic images demonstrate the detailed features of placental development. The lambda sign was established for the diagnosis of dichorionic placenta and the T sign for monochorionic placenta at the end of the first trimester. Other sonographic findings of the twin to twin transfusion syndrome are monochorionicity, same sex, polyhydramnios, permanently filled bladder in the recipient, and oligo/anhydramnios of the donor with a slightly filled or empty bladder. Fetoscopic laser treatment has become an accepted procedure to coagulate the placental anastomoses. This development is supported by actual studies about psycho- and neuromotoric development in early childhood, which shows a lower rate of disabled children in the group receiving laser therapy in comparison to the group undergoing amnioreduction. Twin pregnancies complicated by twin to twin transfusion syndrome should be treated in specialized prenatal centers.     

Diagnostik und Therapie der auditorischen Synaptopathie/Neuropathie

Pathological auditory brainstem responses (lack of responses, elevated thresholds and perturbed waveforms) in combination with present otoacoustic emissions are typical audiometric findings in patients with a hearing impairment that particularly affects speech comprehension or complete deafness. This heterogenous group of disorders first described as “auditory neuropathy” includes dysfunction of peripheral synaptic coding of sound by inner hair cells (synaptopathy) and/or of the generation and propagation of action potentials in the auditory nerve (neuropathy). This joint statement provides prevailing background information as well as recommendations on diagnosis and treatment. The statement focuses on the handling in the german language area but also refers to current international statements.     

Aktuelle Leitlinien zur interventionellen Mammadiagnostik

Minimally invasive diagnostic procedures for the breast under mammography, ultrasound, and magnetic resonance guidance have led to a higher specificity of imaging techniques and a decrease in open biopsy of the breast. The percutaneous approach is more cost and time effective and reduces morbidity compared with open biopsy. The “Step-3-guideline for early breast cancer detection in Germany” represents the first national guidelines for a nationwide, quality assured, early breast cancer detection program, including recommendations for minimally invasive breast diagnostics. Indications for ultrasound guided vacuum biopsy of the breast are summarized in the “Consensus on the use and technique of vacuum-assisted sonographic breast biopsy” by the Study Group on Minimally Invasive Breast Interventions (AG MiMi) of the German Society of Senology (DGS).     

中重度斑块型银屑病患者efalizumab（Raptiva）（CLEAR）试验获得的临床经验：一项国际性随机、安慰剂对照的Ⅲ期试验

背景：Efalizumab（抗-CD11a）是一种人源化单克隆抗体，它可阻断银屑病发病机制中涉及的多种T细胞依赖作用，这些作用包括T细胞活化、向皮肤迁移、在银屑病皮肤中再活化以及与角质形成细胞的相互作用。目的：这项多国、随机、双盲、安慰剂对照、平行组试验旨在评价与安慰剂组相比，efalizumab 1．0mg／kg，1次／周，皮下给药治疗12周的安全性和有效性。受试对象为至少对两种系统治疗因无效、无法耐受或有禁忌证而不适用的有高度需要的银屑病患者。病例／方法：患者有中重度斑块型银屑病[受累面积≥10％体表面积，银屑病面积和严重度指数（PASI）≥12．0]按2：1的比例随机分为efalizumab治疗组和安慰剂组。主要有效终点为治疗12周时意向性处理人群中PASI改善比率≥75％（PASI-75反应）的患者比例。次要终点包括PASI改变、稳定的医师全面评估指标（PGA）、PGA相对于基线的改变和受累体表面积的百分比。结果：纳入793例患者（其中529例接受efalizumab治疗，264例用安慰剂），其中包括526例高度需要治疗的患者（其中342例接受efalizumab治疗，184例用安慰剂）。治疗12周后高度需要治疗患者中efalizumab组PASI．75为29．5％，安慰剂组为2．7％（P〈0．0001）；在全部研究人群中efalizumab组PASI-75率31．4％，安慰剂组为4．2％（P〈0．0001）。次要终点结果显示在高度需要治疗的患者和全部人群中，efalizumab组的疗效均优于安慰剂组。本研究证实efalizumab是一种安全疗法，在高度需要治疗组和全部研究组都未证实有系统毒性。结论：在高度需要治疗和更广泛的中重度银屑病患者中efalizumab的疗效和安全性相当。考虑到该药已证实的有效性和安全性，efalizumab成为中重度斑块型银屑病成年患者包括高度需要治疗患者的有效疗法。