Guidance on radiation dose limits for the lens of the eye: overview of the recommendations in NCRP Commentary No. 26

Abstract

Purpose: This review summarizes the conclusions and recommendations of the new National Council on Radiation Protection and Measurements (NCRP) Commentary No. 26 guidance on radiation dose limits for the lens of the eye. The NCRP addressed radiation protection principles in respect to the lens of the eye, discussed the current understanding of eye biology and lens effects, reviewed and evaluated epidemiology, and assessed exposed populations with the potential for significant radiation exposures to the lens while suggesting monitoring and protection practices.

Conclusions: Radiation-induced damage to the lens of the eye can include the loss of clarity resulting in opacification or clouding several years after exposure. The impact is highly dependent on the type of radiation, how the exposure of the lens was delivered, the genetic susceptibilities of the individual exposed, and the location of the opacity relative to the visual axis of the individual. The preponderance of epidemiological evidence suggests that lens damage could occur at lower doses than previously considered and the NCRP has determined that it is prudent to reduce the recommended annual lens of the eye occupational dose limit from an equivalent dose of 150?mSv to an absorbed dose of 50?mGy. Significant additional research is still needed in the following areas: comprehensive evaluation of the overall effects of ionizing radiation on the eye, dosimetry methodology and dose-sparing optimization techniques, additional high quality epidemiology studies, and a basic understanding of the mechanisms of cataract development.     

羰基蛋白研究进展

综述了羰基蛋白在体内生成的原理和蛋白质氧化损伤与多种疾病的关系，并对测定羰基蛋白含量的常用方法进行了介绍。     

Quality of life and subjective well-being during treatment with antipsychotics in out-patients with schizophrenia

OBJECTIVE: To assess the Quality of Life (QOL) in outpatients with schizophrenia under antipsychotics from two perspectives: a "subjective" perspective as rated by the patient and an "objective" perspective as rated by the physician. METHOD: EASE (External Assessment of Quality of Life in Out-patients with Schizophrenia) is a 12-month, prospective, naturalistic study of the QOL in patients on antipsychotic treatment for schizophrenia in an out-patient setting in Germany. The study included 1462 patients who were initiated on a new antipsychotic or switched to another antipsychotic. The Subjective Well-being under Neuroleptics scale (SWN) and the Quality of Life Scale (QLS) were used to assess the QOL in these patients. The Clinical Global Impression (CGI) scale was used to assess overall symptom severity. Four cohorts were identified and evaluated: (a) patients treated with olanzapine monotherapy (N=1007), (b) another atypical antipsychotic as monotherapy (N=335), (c) a typical antipsychotic as monotherapy (N=32) and (d) combination therapy with more than one antipsychotic (N=88). RESULTS: QOL as assessed by both SWN and QLS improved in all treatment cohorts. SWN responses in the respective cohorts were (a) 52.3%, (b) 38.8%, (c) 31.3% and (d) 44.3%, whilst the QLS responses were (a) 58.2%, (b) 45.1%, (c) 59.4% and (c) 40.9%. Symptom severity as assessed by the CGI also improved over time regardless of the type of antipsychotic. An increase of one point on the CGI corresponded to a change in SWN total score of -9.67 points and a change in QLS total score of -13.36 points. CONCLUSIONS: Both QOL and symptom severity improved over the 12-month study period, regardless of the type of antipsychotic taken. QOL improvement as perceived both from a "subjective" and an "objective" perspective was greatest in the cohort on olanzapine monotherapy.     

Morphological measurements of lumbar pedicles in Egyptian population using computerized tomography and cadaver direct caliber measurements

Introduction

Transpedicular spinal fixation has recently been the focus of increased attention in several institutions throughout the world, but its safety and efficacy require a precise knowledge of the lumbar pedicles and their relations with neural structures.

Objective

In this study, it was aimed at studying the morphometry of the lumbar pedicle in Egyptian population for more safety and better efficacy during pedicle screw fixation and assessment of the accuracy of CT pedicle measurements.

Patients and methods

Study of the lumbar pedicles was conducted using CT scanning for lumbar blocks of five cadavers together with 75 cases of lumbar disc patients to clarify the lumbar pedicle morphology in Egyptian population. Measurements of the axial length, the axial angle, the pedicle breadth, and endosteal thickness were performed on CT images obtained at the middle of the cranio-caudal axis of the pedicle of patients and cadavers. Moreover, these measurements were reviewed by direct caliper measurements in these cadavers.

Results

This study illustrated that the axial length of pedicles is around 5 cm at all lumbar levels with negligible shortening at L₄ and L₅. The angels of inclination of the lumbar pedicle axis on the midline are more obtuse than the known Western measurements and becoming more obtuse from L₁ to L₅. The study clarified that the pedicle breadth becomes progressively thicker from L₁ (6.6 mm) to L₅ (18.5 mm) and the endosteal thickness follows the pedicle breadth becoming thicker at L₅ (8.3 mm) than at L₁ (3.8 mm). We could not detect any statistically significant difference between all the above-mentioned measurements when we compared the direct caliper measurements of the cadavers with its CT measurements and with patients CT measurements. Wide range of measurements of the lumbar pedicle for each particular level was noticed.

Conclusion

CT pedicle measurements are accurate indicators for the actual pedicle morphometry. The Egyptian lumbar pedicles differ in some aspects from the pedicles of other populations. The pedicle screw diameter, the screw length, and the angle of its insertion are better to be tailored according to the CT pedicle measurements of each patient.     

广西妇女生理骨盆临床与X线测量值相关和回归方程的探讨

本文研究广西壮、汉、仫佬、侗、瑶5个民族的生理骨盆、探索出临床外测量的4条径线-髂棘间径、髂嵴间径、骶耻外径及坐骨结节间径,与相对应的X线测量4条盆腔内径之间呈显著的正相关,相关系数r有显著意义.同时列出回归方程及各组数值的换算表.     

Splenic involvement in lymphomas. Evaluation on serial CT examinations

Purpose: To prospectively evaluate changes in splenic volume (SV) on serial CT of patients with lymphoma and correlate them with other indicators of the disease process.Material and Methods: SV was calculated in 290 abdominal CT examinations of 58 consecutive adults with lymphoma (42 non-Hodgkin's lymphoma, 16 Hodgkin's disease). Each patient had one CT investigation before, 2 during chemotherapy and 2 post-chemotherapy. The changes in SV were correlated with clinical, laboratory and other imaging indicators of the disease process.Results: Three groups of patients were identified. Group A (n=20) presented no changes in SV, showed no splenic parenchymal abnormalities and had normal SV and serum lactic dehydrogenase (S-LDH). Group B (n=25) presented a decrease in SV during treatment suggesting response to therapy. Splenic parenchymal abnormalities (n=5) and other subdiaphragmatic sites of involvement (n=20) underwent remission during treatment. Eighteen patients with high S-LDH at presentation showed normal values during therapy. Group C (n=12) showed an increase in SV post-therapy associated with manifestations of disease recurrence. The S-LDH levels were elevated in 10 patients at the same time.Conclusion: Quantitatively assessed splenic size on CT may serve as an indicator of splenic involvement in the course of lymphomas.     

Inhalational and dermal exposures during spray application of biocides

Data on inhalational and potential dermal exposures during spray application of liquid biocidal products were generated. On the one hand, model experiments with different spraying devices using fluorescent tracers were carried out to investigate the influence of parameters relevant to the exposure (e.g. spraying equipment, nozzle size, direction of application). On the other hand, measurements were performed at selected workplaces (during disinfection operations in food and feed areas; pest control operations for private, public and veterinary hygiene; wood protection and antifouling applications) after application of biocidal products such as Empire 20, Responsar SC, Omexan-forte, Actellic, Perma-forte; Fendona SC, Pyrethrum mist; CBM 8, Aldekol Des 03, TAD CID, Basileum, Basilit. The measurements taken in the model rooms demonstrated dependence of the inhalation exposure on the type of spraying device used, in the following order: "spraying with low pressure" < "airless spraying" < "fogging" indicating that the particle diameter of the released spray droplets is the most important parameter. In addition inhalation exposure was lowest when the spraying direction was downward. Also for the potential dermal exposure, the spraying direction was of particular importance: overhead spraying caused the highest contamination of body surfaces. The data of inhalational and potential dermal exposures gained through workplace measurements showed considerable variation. During spraying procedures with low-pressure equipments, dose rates of active substances inhaled by the operators ranged from 7 to 230 microg active substance (a.s.)/h. An increase in inhaled dose rates (6-33 mg a.s./h) was observed after use of high application volumes/time unit during wood protection applications indoors. Spraying in the veterinary sector using medium-pressure sprayers led to inhaled dose rates between 2 and 24mga.s./h. The highest inhaled dose rates were measured during fogging (114 mg a.s./h) and after-high-pressure applications in the antifouling sector (110-300 mg a.s./h). The potential dermal exposure of spray operators was lowest (dose rates from 0.2 to 7 mg a.s./h) in the areas of food and feed disinfection and private and public hygiene during spraying with low-pressure devices. During fogging, wood protection and antifouling applications, high-potential dermal exposures of the operators were determined. Dermal dose rates varied between 100 and 34,000 mg a.s./h.     

Patient radiation exposure during coronary angiography and intervention

Purpose: To prospectively register fluoroscopic and cine times in a random fashion, and to measure patient radiation exposure from routine coronary angiography and coronary balloon angioplasty. We also evaluated an optional dose reduction system used during interventions.Material and Methods: The incident radiation to the patient was measured as kerma area product (KAP) in Gycm², obtained from an ionisation chamber mounted on the undercouch tube during 65 coronary angiography procedures and another 53 percutaneous transluminal coronary angioplasties (including 29 stent procedures), mostly directly following complete coronary angiography.Results and Conclusion: The values from coronary angiography were comparable to other reports with a mean fluoroscopic time of 4.4 min and a mean KAP value of 62.6 Gycm². The corresponding figures from coronary balloon angioplasty without stenting were lower than otherwise reported, with 8.2 min and 47.9 Gycm², respectively. The use of coronary stents did prolong the mean fluoroscopic time (10.5 min) but did not significantly enhance the patient mean radiation dose (51.4 Gycm²). The dose reduction technique resulted in a significant KAP value reduction of 57%. In conclusion, with regard to radiation exposure, coronary angiography and balloon angioplasty are considered safe procedures.     

The preplanned rhinoplasty

In aesthetic rhinoplasty performed by the extramucosal method, the skeletization of the nose that is obtained allowsmeasurements during the operation. Thereby, it is possible and useful to preplan the rhinoplasty with more accuracy and to inform the patient about the choice to be made. This new approach to rhinoplasty is safer and more precise and provides for (1) a choice of preplanned result (based on artistic technique and psychological reasons), (2) measurements for the plan, and (3) transfer of this plan to the patient during the operation.