Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Acceptance Process”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 991 records · Page 55Linked to original sources
PubMed2006

Radiogenic argon distribution within a mineral grain: implications for dating of hydrothermal mineral-forming event in Sludyanka complex, Siberia, Russia.

Usually, in age-determination procedures, the experimenter is interested in the mean concentrations of parent and daughter substances. However, the structure of a solution of the Fick's diffusion equation enables one to specify a procedure, allowing, through macroscopic experiments, one to determine the distribution of radiogenic argon (as well as any of other isotopes) within a mineral grain. Argon, influenced in the geological past by a metamorphic event, has a half-sinusoidal distribution, whereas argon preserved in geological time has a rectangular distribution. The ratio of the quantity of argon of the first type to the total argon is called an alpha-factor. It is believed that this coefficient can be of great interest for geochronological studies, being a symptom of virtual Ar losses and the time instant, at which they happened. A laboratory procedure and a mathematical algorithm to determine the alpha-factor are developed. As an example, a determination of the alpha-factor on a vein-phlogopite from the well-studied Sludyanka deposit, Southern Baikal, Siberia, Russia, is described. Rb-Sr isochron age on phlogopite-calcite-apatite paragenetic assemblage yielded 460+/-7 Ma and is constrained by U-Pb zircon ages of 471+/-1 and 447+/-2 Ma, respectively, on an emplacement of early syenites and monzonites and later 'post-phlogopitic' pegmatites [E.B. Salnikova, S.A. Sergeev, A.B. Kotov, S.Z. Yakovleva, R.H. Steiger, L.Z. Reznitskiy, E.P. Vasil'ev. U-Pb zircon dating of granulite metamorphism in the Sludyanskiy complex, Eastern Siberia. Gondwana Res., 1, 195-205 (1998). L.Z. Reznitskii, G.P. Sandimirova, Y.A. Pakhol'chenko, S.V. Kuznetsova. The Rb-Sr age of phlogopite deposits in Sludyanka, southern Baikal region. Dokl. Earth Sci., 367, 711-713 (1999). L.Z. Reznitskii, A.B. Kotov, E.B. Salnikova, E.P. Vasil'ev, S.Z. Yakovleva, V.P. Kovach, A.M. Fedoseenko. The age and time span of the origin of phlogopite and lazurite deposits in the Southwestern Baikal area: U-Pb geochronology. Petrology, 8, 66-76 (2000).]. In this study, the phlogopite gave an apparent K-Ar age of 365.6+/-10.4 Ma which has no geological meaning. The alpha-factor of 0.27 was derived from a laboratory kinetic experiment. The age determined by the rectangularly distributed argon corresponded to alphax0.129 nmm3/g (total radiogenic argon in the sample)=94.17 nmm3/g, and an age of approximately 274 Ma (e.g. a period without any argon losses). Here, at the first sight, we deal with common argon losses not conjugated with any geological event, because after 447 Ma only lower temperature (in a range of 50-300 degrees C) hydrothermal processes were recorded. A paragenetic phlogopite-bearing vein mineral, hyalophane, having a disturbed Rb-Sr isotopic system, however, yielded 40Ar/39Ar subplateau age of 271+/-2 Ma [V.V. Ivanenko, M.I. Karpenko, M.A. Litsarev. Age of the Sludyanka phlogopite deposits (in Russian; data of the 39Ar-40Ar method). In Geological Series 5, pp. 92-98, Izvestiya Akademii Nauk SSSR, Moskva (1990).], marking similar timing of the K-Ar isotopic system closure. This indicates that K-Ar isotopic system in the phlogopite was not closed (or was partially reset) long after its crystallisation and closing of the Rb-Sr system, in spite of the fact that the crystal was not affected by processes having temperatures above the accepted closure temperatures for micas. There seems to have acted an exchange mechanism of OH-groups between surrounding fluid and hydrocrystal structure. Thus the argon loss did not occur, spontaneously, but argon particles seem to have been captured and carried to the mineral surface by vacancies formed during displacements of OH-groups.

Argon↗
PubMed1999

Characterization and regulation of catabolic genes.

Although a wide range of microorganisms have been discovered that are able to degrade highly stable, toxic xenobiotics, still many pollutants persist in the environment. Recent advances in the field of r-DNA technology has provided solutions to these problems. One important factor limiting the bioremediation of sites contaminated with certain hazardous wastes is the slow rate of degradation. This slow rate limits the practicality of using bacteria in remediating contaminated sites. It is possible to extend the range of substrates that an organism can utilize. It is even possible to endow an organism with the ability to degrade a predetermined range of xenobiotics. Because biotechnological processes are based on natural activities of microorganisms and constitute variations in classic domestic waste treatment processes, they are publicly more accepted. This is an area where genetic engineering can make a marked improvement by manipulating catabolic genes of microorganisms. Advances in r-DNA technology have opened up new avenues to move toward the goal of genetically engineered microorganisms to function as "designer biocatalysts" in which certain desirable biodegradation pathways or enzymes from different organisms are brought together in a single host with the aim of performing specific detoxification. In the last 2 decades much progress has been made in this direction, and as a result catabolic genes have been cloned and characterized for organochlorines, polychlorinated biphenyls, chlorobenzoates, naphthalene etc. The aim of this review is to provide an insight in the recent advances made on characterization and expression of catabolic genes that encode the degradation/detoxification of these persistent and toxic xenobiotic compounds.

Anthracenes↗
PubMed2002

The feasibility of paper-based Tracking Codes and electronic medical record systems to monitor tobacco-use assessment and intervention in an Individual Practice Association (IPA) Model health maintenance organization (HMO).

Despite evidence of its effectiveness, tobacco cessation is not systematically addressed in routine healthcare settings. Its measurement is part of the problem. A pilot study was designed to develop and implement two different tobacco tracking systems in two independent primary care offices that participated in an IPA Model health maintenance organization in Portland, Oregon. The first clinic, which utilized a paper-based charting system, implemented CPT-like tracking codes to measure and report tobacco-cessation activities, which were eventually included in the managed-care organization's (MCO) claims database. The second clinic implemented an electronic tracking system based on its computerized electronic medical record (EMR) charting system. This paper describes the pilot study, including the processes involved in building provider acceptance for the new tracking systems in these two clinics, the barriers and successes encountered during implementation, and the resources expended by the clinics and by the MCO during the pilot. The findings from the 3-month implementation period were that documentation of tobacco-use status remained stable at 42-45% in the paper-based clinic and increased from 79% to 88% in the EMR clinic. This pilot study demonstrated that Tracking Codes are a feasible preventive-care tracking system in paper-based medical offices. However, high levels of effort and support are needed, and a critical mass of insurers and health plans would need to adopt Tracking Codes before widespread use could be expected. Results of the EMR-based tracking system are also reviewed and discussed.

Costs and Cost Analysis↗
PubMed1985

Human O6-alkylguanine-DNA alkyltransferase fails to repair O4-methylthymine and methyl phosphotriesters in DNA as efficiently as does the alkyltransferase from Escherichia coli.

The repair of alkylated poly(dT) annealed to poly(dA) and alkylated DNA was studied using human cells in culture, extracts of human liver and Escherichia coli, and partially purified O6-alkylguanine-DNA alkyltransferase from human liver. The human alkyltransferase behaved as if the transferring and accepting functions of the repair process resided on the same molecule. Extracts of E. coli efficiently repaired O6-methylguanine, O4-methylthymine and methyl phosphotriesters in DNA. In contrast, cultured human cells and extracts from human liver repaired O6-methylguanine but did not repair O4-methylthymine or methyl phosphotriesters in DNA nearly as efficiently as did the E. coli extracts.

Alkylation↗
PubMed1986

Apparent synergy in lung carcinogenesis: interactions between N-nitrosoheptamethyleneimine, particulate cadmium and crocidolite asbestos fibres in rats.

Environmental carcinogenesis in man is widely accepted to be a multifactorial process, and in the causation of lung cancers it is suspected that low levels of systemic carcinogens may act synergistically with inhaled particulates so that some exposed individuals are at increased risk. In the present study the carcinogenic effects of low levels of industrially and environmentally significant particulate materials (crocidolite asbestos and metallic cadmium) and a putative systemic carcinogen, N-nitrosoheptamethyleneimine (NHMI), were investigated in the laboratory rat, using this as a model of potential human exposure. The overall lung tumour incidence rate in the group of animals receiving crocidolite, cadmium and NHMI (14/45) was significantly higher than in the groups of animals receiving either crocidolite and cadmium together (2/51) or crocidolite and NHMI together (7/42). The results demonstrated an apparent synergy between cadmium and NHMI in the presence of crocidolite in the causation of lung cancer in rats, a finding which was confirmed statistically. This study helps to further evaluate and define the roles of asbestos and particulate cadmium in the causation of lung cancer. It is suggested that people who are exposed through occupation and/or environment to cadmium and asbestos and to low levels of systemic carcinogens may show a significantly elevated risk of lung cancer.

Animals↗
PubMed1988

Apparent synergy between chrysotile asbestos and N-nitrosoheptamethyleneimine in the induction of pulmonary tumours in rats.

Environmental carcinogenesis in man is widely accepted to be a multifactorial process, and in the causation of lung cancers it is suspected that low levels of systemic carcinogens may act synergistically with inhaled particulates so that some exposed individuals are at increased risk. In the present study the carcinogenic effects of low levels of industrially/environmentally significant particulate materials (chrysotile asbestos and metallic cadmium) and a putative systemic carcinogen, N-nitrosoheptamethyleneimine (NHMI), were investigated in the laboratory rat, using this as a model of potential human exposure. The overall lung tumour incidence rate in the groups of animals receiving chrysotile and NHMI together (8/50) or chrysotile, cadmium and NHMI together (6/44) was substantially higher than in the groups receiving chrysotile alone (1/86) or chrysotile and cadmium (1/94) or NHMI alone (2/48). The results demonstrated apparent synergy between chrysotile and NHMI in the induction of lung tumours. Incidence of pulmonary hyperplastic lesions paralleled the trend in tumour incidence. Cadmium had little or no influence on the incidence of either lung tumours or hyperplastic lesions. This study helps to evaluate further the role of asbestos in the causation of lung cancer. It is suggested that people who are or have been exposed to chrysotile asbestos may show a significantly elevated risk of lung cancer if concomitantly or subsequently exposed to tumour initiating agents.

Animals↗
PubMed2006

Identification of 17 Pseudomonas aeruginosa sRNAs and prediction of sRNA-encoding genes in 10 diverse pathogens using the bioinformatic tool sRNAPredict2.

sRNAs are small, non-coding RNA species that control numerous cellular processes. Although it is widely accepted that sRNAs are encoded by most if not all bacteria, genome-wide annotations for sRNA-encoding genes have been conducted in only a few of the nearly 300 bacterial species sequenced to date. To facilitate the efficient annotation of bacterial genomes for sRNA-encoding genes, we developed a program, sRNAPredict2, that identifies putative sRNAs by searching for co-localization of genetic features commonly associated with sRNA-encoding genes. Using sRNAPredict2, we conducted genome-wide annotations for putative sRNA-encoding genes in the intergenic regions of 11 diverse pathogens. In total, 2759 previously unannotated candidate sRNA loci were predicted. There was considerable range in the number of sRNAs predicted in the different pathogens analyzed, raising the possibility that there are species-specific differences in the reliance on sRNA-mediated regulation. Of 34 previously unannotated sRNAs predicted in the opportunistic pathogen Pseudomonas aeruginosa, 31 were experimentally tested and 17 were found to encode sRNA transcripts. Our findings suggest that numerous genes have been missed in the current annotations of bacterial genomes and that, by using improved bioinformatic approaches and tools, much remains to be discovered in 'intergenic' sequences.

Computational Biology↗
PubMed1993

Multistep transformation in low-grade lymphoproliferative diseases.

BACKGROUND: Carcinogenesis, the formation of solid tumors, is now widely accepted to represent a multistep process. Several genetic events, activation of proto-oncogenes and inactivation of tumor suppressor genes, are involved. DESIGN: Review of the literature for evidence that the concept of multistep transformation has relevance also for the formation of low-grade lymphoproliferative diseases. RESULTS AND CONCLUSION: The common translocations in low-grade lymphoid tumors are probably early events, predominantly involved in the activation of oncogenes, leading to growth stimulation or prolonged cell survival. As a result 'monoclonal lymphoproliferative disorders of undetermined significance (MLDUS)' occur, undetermined, because some translocations may not always led to tumor formation. For progression to full malignancy, additional genetic events are required besides sequential selection of variant subpopulations within the neoplastic clone. Recent data indicate that mutations and deletions of putative tumor suppressor genes, including the P53 and retinoblastoma genes, are also involved in the progression of lymphoproliferative disorders. A list of lymphoproliferative diseases stressing this concept of multistep transformation is presented in this article.

Animals↗
PubMed2000

Cardiac transplantation: the final therapeutic option for the treatment of heart failure.

End-stage heart failure is still associated with a decrease in quality and prognosis of life. Cardiac transplantation remains the final extraordinary therapeutic option for the treatment of truly irreversible end-stage heart failure in all age groups. The selection process of candidates and the acceptance of patients with relative contra-indications is characterized by the experience and skills of an interdisciplinary transplant team, which should have access to different mechanical circulatory support systems for short-term or long-term use: bridging to transplant as well as for recovery.

Actuarial Analysis↗
PubMed2002

Tolerable hearing aid delays. II. Estimation of limits imposed during speech production.

OBJECTIVE: We used real-time processing in a wearable digital hearing aid to examine the effect of processing delay on normal-hearing participants while speaking. Objective and subjective data were recorded so as to permit analysis of both the production and perception of speech read aloud from a script. We also asked participants to rate the disturbance of the echo introduced by the delay. DESIGN: Thirty-two (16M, 16F) participants were fitted binaurally with behind-the-ear (BTE) aids connected to a digital processor. A 4 mm Libby horn, surrounded by an expanding foam earplug, conducted processed sound into each ear canal. The processor provided either linear processing or three-channel, fast-acting wide dynamic range compression, independently to each ear. Insertion gains were set, using a KEMAR manikin, to be 0 dB over a wide frequency range, for frontally presented speech with a free field level of 65 dB SPL. Additionally, the aids introduced one of four selectable delays (7 to 43 msec) between the BTE microphone and receiver. After a short period of acclimatization, each participant read 16 prose passages of about 500 words in length in each of two similar-sized rooms with markedly different acoustics: reverberant and nonreverberant. For each passage, a subjective rating of the level of disturbance of the perceived echo was recorded, as well as simultaneous recordings from a microphone and a Laryngograph, which directly records glottal pulses. RESULTS: Disturbance ratings generally increased monotonically with increasing delay. Averaged results show that a delay between 25 and 30 msec is rated as "disturbing." Measures were also taken of word production rate, speech level and range of level as well as fundamental frequency and range of fundamental frequency. For these measures of speech production, there was no significant effect until the delay exceeded 30 msec. There was little effect of acoustic environment or aid processing (linear or compression). CONCLUSIONS: The acceptability of delays introduced by digital hearing aids is primarily determined by aspects of the perception of self-generated speech. Speech production, on average, is hardly affected unless the processing delay exceeds 30 msec. The permissible limit of 20 to 30 msec is smaller than the delays at which audio-visual integration is disrupted.

Adolescent↗
PubMed1981

Objective obstacles in hiring disabled persons -- the employers' point of view.

In the comprehensive rehabilitation process, one of the most accepted criteria for success or failure is the suitable placement of the client in the open employment market. The present study examined employer's attitudes toward hiring disabled persons. The sample consisted of 233 employers in the public and private sectors of the Israeli economy, and the method entailed interviewing each employer about his attitudes toward the risks of employing disabled persons, his actual hiring practices, and his expected response to financial aid for surmounting technical obstacles (architectural barriers and inappropriate work methods and tools). Interpretation of the results indicated that employers' reluctance to hire disabled employees was often explained by the existence of technical obstacles. However, when the possibility of financial aid for eliminating these obstacles was proposed, the employers responded with reservation. Although Israeli has mandated legislation requiring the employment of disabled war veterans, not all employers were aware of this, and almost half of those who were did not employ disabled persons. Evidently, legislation does not suffice in order to ensure actual hiring of disabled persons. In order to increase compliance with the law, and to encourage hiring of disabled persons who are not war veterans, it was suggested that more information be provided to the employers on the possibilities of employing disabled persons, with emphasis placed on the positive aspects of the disabled worker's true potential. Additional methods that should be applied to encourage employment include appropriate vocational training of disabled persons themselves and demonstration before the employers of the practical conditions under which successful employment is possible.

Architectural Accessibility↗
PubMed2001

Prognostic value of electromyography in acute peripheral facial nerve palsy.

OBJECTIVE: To analyze the value of electromyography in predicting recovery from acute idiopathic facial nerve paralysis. STUDY DESIGN: Retrospective case-series review. SETTING: University-based hospital department of otorhinolaryngology/head neck surgery. PATIENTS: Three hundred fifty-five patients with sudden facial paralysis of unknown cause (Bell's palsy). INTERVENTION: Treatment consisted uniformly of high-dose prednisolone, dextran, and pentoxifylline. Prognostication was based on electromyography performed not earlier than 10 to 14 days after the onset of palsy. The findings were classified according to Seddon into neurapraxia and axonotmesis/ neurotmesis. There is an inherent statement on prognosis in this classification because neurapraxia is presumed to recover completely within 8 to 12 weeks, whereas axonotmesis is most likely to be followed by sequelae. MAIN OUTCOME MEASURES: Facial nerve function after 6 months. RESULTS: Complete recovery was predicted correctly in 92.4% of cases. For the relatively rare and therefore principally more difficult predictable event defective recovery prognosis was still accurate in 80.8%. CONCLUSION: The detection of spontaneous fibrillation in needle electromyography is a reliable sign predicting unfavorable outcome. An accuracy of 80.8% for predicting unfavorable outcome may be sufficient to advise patients what to expect in the course of their facial nerve disorder. However, it seems dubious to build a decision about surgical intervention on such a test, because in the process, unnecessary surgery would be accepted for as much as one fifth of the patient population.

Acute Disease↗
PubMed2006

Current status of digital mammography for screening and diagnosis of breast cancer.

PURPOSE OF REVIEW: Digital mammography is becoming the preferred technique for investigation of the breast. It is important, therefore, to analyze not only the accuracy of this technique in the screening and the diagnostic environment but also to evaluate its strengths and limits. In addition, communication with other specialists inside and outside the hospital is essential. RECENT FINDINGS: Recent publications of large clinical trials have shown that digital mammography is as accurate as film-screen mammography in a screening setting. Technical protocols for acceptance testing of these modalities are emerging but they are not yet complete. The literature shows that reading on soft copy may be preferred to hard copy. The high cost is still an important limiting factor in the easy introduction of full-field digital mammography in a hospital. SUMMARY: Digital mammography is becoming the method of choice in the detection and characterization of breast cancer. Today, physical and technical protocols as well as large clinical trials are assessing the performance of this technology. A lot of work remains in the optimization of the different parts of the imaging chain: exposure setting, acceptability of detectors, dedicated post processing, viewing conditions and computer-aided detection. In parallel with these developments, newer digital technologies are being explored (tomosynthesis).

Breast Neoplasms↗
PubMed2005

The standardization of pancreatic donors for islet isolations.

BACKGROUND: Islet transplantation has proven to be a successful treatment for type 1 diabetes mellitus. The aim of this study was to establish an algorithm by which the combination of the donor quality and pancreas quality was given a numerical score from 0 to 100 for use in determining the quality of a pancreas for islet isolation. METHODS: We retrospectively analyzed 326 pancreases and the outcomes of their respective isolations. Specific donor variables and physical characteristics were identified and weighted according to their influence on the success of the isolation. For each variable, ranges and point weightings were established based on our laboratory experience and literature review. RESULTS: Analysis of the data showed a strong association of the donor point with isolation outcome. Pancreases with lower donor point scores had lower transplant success rates, whereas higher donor point scores in turn produced higher transplant rates. CONCLUSIONS: This scoring system has proven to be useful in guiding the decision process as to whether to accept a particular pancreas for a favorable isolation outcome.

Adult↗
PubMed2005

Light microscopic identification and semiquantification of polyethylene particles in methylmethacrylate and paraffin-embedded experimental bone implant specimens.

The aim of this study was to evaluate the identification of polyethylene (PE) particles in relatively thick methylmethacrylate (MMA) sections widely used in bone implant research. The sensitivity and specificity were compared between decalcified paraffin-embedded oil red O (ORO) stained and MMA-embedded sections using polarized light. Furthermore, we introduced a grading system to semiquantify the level of PE particles in peri-implant tissue. Paraffin-embedded and MMA-embedded sections were compared concerning intra-observer agreement of the grading system. Moreover, the semiquantitative assessment of particle level was compared between the two section types. We found a sensitivity and specificity of polarized light of 100% for both paraffin ORO-stained and MMA sections. The intra-observer agreement on both types was comparable and acceptable. The ratings of differently processed blocks (MMA- and paraffin-embedded) originating from the same bone implant specimen showed good correlation. Our study showed that relatively thick MMA sections were just as suitable as ORO-stained paraffin sections concerning peri-implant PE particle migration analysis. MMA sections do not allow analysis at cellular level, but unbiased estimation of bone ingrowth into the implant surface based on stereological principles is possible.

Animals↗
PubMed1993

An educational model for medical appointments.

A model of planned appointments to the training and consultant grades in the National Health Service is proposed. Contracts in each grade would begin and end at fixed dates. The aim of the model is to provide a coherent educational and career plan for each doctor with minimal disruption of the clinical service. It is proposed that a phased introduction of the scheme would allow the process of change to be acceptable and the model to be evaluated before a commitment to its full introduction is made.

Career Mobility↗
PubMed2006

Justified commitments? Considering resource allocation and fairness in Medecins sans Frontieres-Holland.

Non-governmental aid programs are an important source of health care for many people in the developing world. Despite the central role non-governmental organizations (NGOs) play in the delivery of these vital services, for the most part they either lack formal systems of accountability to their recipients altogether, or have only very weak requirements in this regard. This is because most NGOs are both self-mandating and self-regulating. What is needed in terms of accountability is some means by which all the relevant stakeholders can have their interests represented and considered. An ideally accountable decision-making process for NGOs should identify acceptable justifications and rule out unacceptable ones. Thus, the point of this paper is to evaluate three prominent types of justification given for decisions taken at the Dutch headquarters of Médecins sans Frontières. They are: population health justifications, mandate-based justifications and advocacy-based justifications. The central question at issue is whether these justifications are sufficiently robust to answer the concerns and objections that various stakeholders may have. I am particularly concerned with the legitimacy these justifications have in the eyes of project beneficiaries. I argue that special responsibilities to certain communities can arise out of long-term engagement with them, but that this type of priority needs to be constrained such that it does not exclude other potential beneficiaries to an undesirable extent. Finally, I suggest several new institutional mechanisms that would enhance the overall equity of decisions and so would ultimately contribute to the legitimacy of the organization as a whole.

Community-Institutional Relations↗
PubMed2004

Development and validation of a CT-3D rotational angiography registration method for AVM radiosurgery.

In this paper a novel technique is proposed and validated for radiosurgery treatment planning of arteriovenous malformations (AVMs). The technique was developed for frameless radiosurgery by means of the CyberKnife, a nonisocentric, linac-based system which allows highly conformed isodose surfaces to be obtained, while also being valid for other treatment strategies. The technique is based on registration between computed tomography (CT) and three-dimensional rotational angiography (3DRA). Tests were initially performed on the effectiveness of the correction method for distortion offered by the angiographic system. These results determined the registration technique that was ultimately chosen. For CT-3DRA registration, a twelve-parameter affine transformation was selected, based on a mutual information maximization algorithm. The robustness of the algorithm was tested by attempting to register data sets increasingly distant from each other, both in translation and rotation. Registration accuracy was estimated by means of the "full circle consistency test." A registration quality index (expressed in millimeters) based on these results was also defined. A hybrid subtraction between CT and 3DRA is proposed in order to improve 3D reconstruction. Preprocessing improved the ability of the algorithm to find an acceptable solution to the registration process. The robustness tests showed that data sets must be manually prealigned within approximately 15 mm and 20 degrees with respect to all three directions simultaneously. Results of the consistency test showed agreement between the quality index and registration accuracy stated by visual inspection in 20 good and 10 artificially worsened registration processes. The quality index showed values smaller than the maximum voxel size (mean 0.8 mm compared to 2 mm) for all successful registrations, while it resulted in much greater values (mean 20 mm) for unsuccessful registrations. Once registered, the two data sets can be used for CyberKnife treatment planning. Target delineation is performed on 3DRA while dose calculation and DRR generation are performed on CT. In conclusion, a method was developed for using 3DRA images for AVM frameless radiosurgery treatment planning. The method proved to be feasible, robust, and accurate for clinical use. 3DRA can be performed at different times or locations compared to standard, frame based stereotactic angiography. Unlike two-dimensional angiography, 3DRA allows examination of the shape of the AVM and of the surrounding target from any arbitrary point of view during treatment planning. The method can be applied to any case of intermodality registration, is operator-independent, and allows estimation of registration quality. Further research is desirable to improve time resolution in order to distinguish between feeding and draining vessels.

Algorithms↗