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The attributes of naturally decaying atoms, known as radioisotopes, give rise to several applications across many aspects of modern day life see also information paper on The Many Uses of Nuclear Technology. There is widespread awareness of the use of radiation and radioisotopes in medicine, particularly for diagnosis identification and therapy treatment of various medical conditions.

In developed countries a quarter of the world population about one person in 50 uses diagnostic nuclear medicine each year, and the frequency of therapy with radioisotopes is about one-tenth of this. Nuclear medicine uses radiation to provide information about the functioning of a person's specific organs, or to treat disease.

In most cases, the information is used by physicians to make a quick diagnosis of the patient's illness. The thyroid, bones, heart, liver, and many other organs can be easily imaged, and disorders in their function revealed.

In some cases radiation can be used to treat diseased organs, or tumours. Five Nobel Laureates have been closely involved with the use of radioactive tracers in medicine. In the USA there are over 20 million nuclear medicine procedures per year, and in Europe about 10 million.

In Australia there are aboutper year,of these using reactor isotopes. Nuclear medicine was developed in the s by physicians with an endocrine emphasis, initially using iodine to diagnose and then treat thyroid disease.

However, the main radioisotopes such as Tcm cannot effectively be produced without reactors. Radioisotopes are an essential part of medical diagnostic procedures. In combination with imaging devices which register the gamma rays emitted from within, they can study the dynamic processes taking place in various parts of the body.

In using radiopharmaceuticals for diagnosis, a radioactive dose is given to the patient and the activity in the organ can then be studied either as a two dimensional picture or, using tomography, as a three dimensional picture.

Diagnostic techniques in nuclear medicine use radioactive tracers which emit gamma rays from within the body. These tracers are generally short-lived isotopes linked to chemical compounds which permit specific physiological processes to be scrutinised.

They can be given by injection, inhalation, or orally. The earliest technique developed uses single photons detected by a gamma camera which can view organs from many different angles. The camera builds up an image from the points from which radiation is emitted; this image is enhanced by a computer and viewed on a monitor for indications of abnormal conditions.

Single photon emission computerised tomography SPECT is the current major scanning technology to diagnose and monitor a wide range of medical conditions.

assessment of residual radioisotopes following f

A more recent development is positron emission tomography PET which is a more precise and sophisticated technique using isotopes produced in a cyclotron. A positron-emitting radionuclide is introduced, usually by injection, and accumulates in the target tissue.

As it decays it emits a positron, which promptly combines with a nearby electron resulting in the simultaneous emission of two identifiable gamma rays in opposite directions.

Fludeoxyglucose F 18

These are detected by a PET camera and give very precise indications of their origin. PET's most important clinical role is in oncology, with fluorine as the tracer, since it has proven to be the most accurate non-invasive method of detecting and evaluating most cancers. It is also well used in cardiac and brain imaging. It is a very powerful and significant tool which provides unique information on a wide variety of diseases from dementia to cardiovascular disease and cancer.

assessment of residual radioisotopes following f

Positioning of the radiation source within rather than external to the body is the fundamental difference between nuclear medicine imaging and other imaging techniques such as X-rays. Gamma imaging by either method described provides a view of the position and concentration of the radioisotope within the body. Organ malfunction can be indicated if the isotope is either partially taken up in the organ cold spotor taken up in excess hot spot.

If a series of images is taken over a period of time, an unusual pattern or rate of isotope movement could indicate malfunction in the organ. A distinct advantage of nuclear imaging over X-ray techniques is that both bone and soft tissue can be imaged very successfully. This has led to its common use in developed countries where the probability of anyone having such a test is about one in two and rising. Every organ in our bodies acts differently from a chemical point of view.

Doctors and chemists have identified a number of chemicals which are absorbed by specific organs. The thyroid, for example, takes up iodine, whilst the brain consumes quantities of glucose.

With this knowledge, radiopharmacists are able to attach various radioisotopes to biologically active substances.The purpose of this document is to provide a generic model that can be used for risk assessment of larviciding and mollusciciding; it aims to harmonize the risk assessment of such pesticides for public health use.

The assessment considers both adults and children all age groups. The purpose of this document is to provide a generic model that can be used for risk assessment of exposure to insecticide products applied as space treatments, both indoors and outdoors, against flying insect vectors and pests of public health importance.

It aims to harmonize the risk assessment of such insecticides for public health use. The assessment considers exposures for both adults and children all ages as well as people in the following specific categories. This second edition provides a generic model that can be used for risk assessment of exposure to insecticide products applied as indoor residual sprays.

It aims to harmonize the risk assessment of such insecticides for public health use in order to generate comparable data for their registering and labelling by national regulatory authorities.

Long-lasting insecticidal nets LNs constitute a core vector control intervention against malaria. A number of new LN products are under development and will require assessment of risks to humans. This document provides an updated generic model that can be used for the risk assessment of exposure to insecticides of individuals sleeping under LNs and during the washing of nets.

In an Annex, exposures and health risks are described for the conventional treatment or retreatment of nets ITNs with an insecticide considering that such practices may still be used in evaluation of ITNs and their use.

The generic model does not include the risks associated with the manufacturing of LNs in a factory environment. This document is a revised and improved version of the procedures and guidelines for testing long-lasting insecticidal nets LNs published in The purpose of this document is to harmonize the testing procedures to generate data for registration and labelling of LNs by national authorities.

The revision has been made considering the lessons learnt in evaluating LNs in laboratory and field. The document also provides procedures and guidelines to evaluate LNs containing new insecticides or mixtures of insecticides. The behaviours can include movement away from a chemical stimulus, interference with host detection attraction inhibition and feeding response.

Ref: ISBN 92 web only. The main purpose of these guidelines is to assist national vector-borne disease control programmes, and other relevant agencies, in monitoring the durability of long-lasting insecticidal mosquito nets LNs under operational conditions.

The information derived by monitoring will be useful in planning the replacement of worn-out nets in an LN programme, making decisions to procure the most suitable LNs for the setting and understanding the factors associated with the durability of LN products. The purpose of these guidelines is to provide specific, standardized procedures and criteria for testing the efficacy of products designed for disinsection in aircraft; and to assist countries in adopting health control measures under the International Health Regulations.

The guidelines are intended for use as a companion to other specific WHO technical guidance documents on avoiding the spread of disease vectors through air travel. In this publication, a generic risk assessment model with worked examples for disinsection of aircrafts with chemical insecticides has been presented first, in Part A, along with the description of the process used to develop the model.

assessment of residual radioisotopes following f

The evaluation of the different types of aircraft disinsection products against the risk assessment model is presented in Part B.

Ref: Environmental Health Criteria ISBN 92 4 This document provides specific and standardized procedures and guidelines for testing mosquito adulticides for indoor residual spraying and for treatment of mosquito nets. This document provides specific and standardized procedures and guidelines for testing larvicides, including bacterial larvicides and insect growth regulators against mosquitoes.

This document provides specific and standardized procedures and criteria for efficacy testing and evaluation of insecticides for indoor and outdoor, ground-applied space spray applications against vectors and pests of public health importance. This document provides specific and standardized procedures and criteria for efficacy testing and evaluation of mosquito repellents for human skin.

SEM_5_Spectroscopy_Lec 3_Pharmacognosy\u0026Phytochemistry II Basics of Phytochemistry Gandhi

This document provides specific and standardized procedures and criteria for efficacy testing and evaluation of specific household insecticide products intended for indoor use against mosquitoes, namely, mosquito coils, vaporizer mats, liquid vaporizers, ambient emanators and aerosols.

The document outlines the general procedures for field trials of residual insecticides against domestic Triatominae, where the aim is to eliminate the domestic bug populations and inhibit reinfestations. The procedure is suitable for village-scale field trials, whose toxicological safety has already been approved.

The procedure also allows for multiple village trials in order to compare the effects of different products, or different formulations of the same product, or different doses of the same formulation. Health Topics. About Us. Skip to main content. Menu Neglected tropical diseases About us Diseases Preventive chemotherapy and transmission control Innovative and intensified disease management Vector ecology and management Neglected zoonotic diseases Water, sanitation and hygiene.

Guidelines and risk assesment models Generic risk assessment model for insecticides used for larviciding and mollusciciding — Second Edition.Metrics details. Automated protocols for measuring and dispensing solutions containing radioisotopes are essential not only for providing a safe environment for radiation workers but also to ensure accuracy of dispensed radioactivity and an efficient workflow.

For this purpose, we have designed ARAS, an automated radioactivity aliquoting system for dispensing solutions containing positron-emitting radioisotopes with particular focus on fluorine 18 F.

The key to the system is the combination of a radiation detector measuring radioactivity concentration, in line with a peristaltic pump dispensing known volumes. To better comply with regulations and to enhance the safety of employees, protocols must be developed that minimize radiation exposure. Automated tools for handling radiation provide a promising approach to reduce radiation exposure [ 2 ]. Furthermore, well-implemented automated systems reduce human error and, thus, allow for a streamlined workflow.

In regard to the development and production of radiotracers, a tool that allows for automated aliquoting of user-specified amounts from a batch of [ 18 F]fluoride solution will eliminate the need for radiation workers to manually draw radioactivity. Moreover, this automated dispenser can be implemented in any step of the radiotracer development and usage pipeline, including not only aliquoting of [ 18 F]fluoride after cyclotron bombardment to support multiple research or production runs but also aliquoting the radiotracer for delivery into a subject.

However, a technical challenge faced in both of these applications is the small volume of original stock solutions and the even smaller volume of individual aliquots. To address the opportunity of significantly increasing safety and accuracy, we have developed ARAS, an automated radioactivity aliquoting system for dispensing solutions containing positron-emitting radioisotopes with particular focus on fluorine 18 F.

ARAS consists of a solid-state radiation detector in series with a peristaltic pump. Two diodes are used in order to suppress the background from long-range keV photons produced from positron-electron annihilation.

These are present when handling positron-emitting radioisotopes like 18 F which is commonly used in PET and is the radioisotope considered in this work. For each batch of radioisotope, the detector is used to perform a one-time calibration to determine the initial reference radioactivity concentration. The peristaltic pump is used to deliver prescribed volumes of [ 18 F]fluoride solutions based on the decay-corrected radioactivity concentration and the desired amount of radioactivity.

The automated design of this system promises to reduce exposure to the operator compared to manual dispensing operations and manual measurements using a dose calibrator. In this work, we describe the design of the prototype system and characterize the system performance.

We also present preliminary examples of possible usage in radiochemistry and in mouse tail vein injections. ARAS was designed to automate aliquoting of solutions containing positron-emitting radioisotopes such as [ 18 F]fluoride. The C-Flex tubing passed through a peristaltic pump and liquid sensor and passed over a radiation detector. For radiochemistry usage, the C-Flex tubing was subsequently attached to a linear stage. Once the tubing was filled, the actuation time was set to dispense a requested volume, given the known flow rate.

Although distribution by volume specification is useful, often, an amount of radioactivity is requested.CBDT issues Detailed guidelines for the implementation of Faceless Assessment Scheme, and role of residual charges in this regard.

Subject: Guidelines for the implementation of Faceless Assessment Scheme, reg:. In view of the above, I am directed to provide the detailed guidelines for the implementation of the Scheme and role of residual charges in this regard. All these functions will be through electronic means for which the NeAC will be the gateway and will function as such for all the flow of information.

No communication of any nature such as above will be made by any of the ReACs. Broadly the functions are as under:. The Pr. In cases of surveys of the International Taxation charge or any other charges, the same will be conducted in collaboration with the Investigation Directorates. The Board has diverted these posts vide order No. The following norm has been adopted for creation of hierarchy in each ReAC:. In furtherance of the same, it is important that the Pr.

CCsIT now issue orders for diversion of posts of Addl. The following guidelines have been adopted in identification of the posts for diversion:. The detailed list of posts identified for diversion are enclosed along with list of residual charges required to be merged. It is very important that the orders for transfer of jurisdiction and diversion of posts at the level of Addl.

It must be ensured that the attached PDF list for diversion of posts of Addl. It is also submitted that while diverting and mentioning that a particular Addl.

The technical and review units may be kept together to the extent possible in bigger buildings. The verification units may be spread out to cover large geographical. All the orders should be passed with effect from The following orders may be passed by the field charges latest by 19 th August, in order to give effect to the changes Board has issued the following notifications and orders which are also available on either the irsofficersonline or incometaxindia websites of the department.

We are also attaching these PDF files as zip files Your email address will not be published. Post Comment. Notice: It seems you have Javascript disabled in your Browser. In order to submit a comment to this post, please write this code along with your comment: fa4af62cf8fcca14a. User Menu. Guidelines to implement Faceless Assessment Scheme Verification related to centralized dissemination of information by the Directorate of Systems, by the VUs.

Review of draft orders by the RUs. Technical support by the TUs. Passing and dispatch of the final orders by the NeAC. Taxpayer facilitation. Rectification proceedings.Positron emission tomography PET allows diagnostic imaging of metabolic function using radioisotopes.

This technology has undergone significant growth and evolution in recent years with most PET scanners now integrated with CT scanners. The main radiotracer in clinical use is F fluorodeoxyglucose. This was initially used as a research tool and in cardiac and neurological applications, but now has an integral role in oncology.

Fluorodeoxyglucose PET has had a major impact on the management of a broad range of malignancies because it is more sensitive than conventional imaging modalities. It is now used for diagnosis, staging and assessing response to therapy in many cancers and in characterising solitary pulmonary nodules. It is important to remember that not all abnormalities on a fluorodeoxyglucose PET scan are due to malignancy, and unexpected findings may need to be evaluated further.

Positron emission tomography PET scanning allows non-invasive diagnostic imaging of metabolic processes using short-lived radioisotopes. In contrast to computerised tomography CT and magnetic resonance imaging MRIwhich provide information on structure, PET can quantify biochemical and physiological function.

PET has been available as a clinical tool in Australia for well over a decade. Facilities have been installed in every mainland state capital city and in Newcastle, New South Wales. At present, only specialists and consultant physicians may refer patients for a PET scan. Problems of patient and organ motion are also significantly reduced with this approach. Radiotracers manufactured from positron emitting isotopes can be used to image a variety of biological processes in the body using a PET scanner.

A positron is a positively charged electron which is emitted from the nucleus of some low molecular weight radioactive isotopes. These include carbon Cnitrogen N and oxygen Owhich are the 'building blocks' of the body, and fluorine F These isotopes have very short half-lives ranging from two minutes for O to minutes for Fand have to be manufactured nearby in a medical cyclotron. These isotopes can then be chemically incorporated into trace quantities of biologically relevant molecules.

The radiotracers have no pharmacological actions. A PET scanner does not directly image positrons. Once a positron is emitted from the nucleus, it travels a short distance several millimetres in soft tissueand then annihilates with a negatively charged electron.

The mass of the two particles is converted to energy in the form of two gamma rays that propagate at o to each other. Coincident gamma ray pairs that travel out of the body are detected by a ring of detectors around the patient.The response to chemoradiotherapy CRT for rectal cancer can be assessed by clinical examination, consisting of digital rectal examination DRE and endoscopy, and by MRI.

A high accuracy is required to select complete response CR for organ-preserving treatment. Confidence levels were used to score the likelihood of CR. Diagnostic performance was calculated by area under the receiver operator characteristics curve, with corresponding sensitivities and specificities. Strategies were assessed and compared by use of likelihood ratios. Areas under the curve were 0. MRI can provide this additional information, which can be critical for decision making.

Therefore, we changed the restaging strategy to routinely include DRE and endoscopy in all patients. Patients provided written informed consent for this restaging study.

CRT consisted of 28 fractions of 1. At DRE, findings were classified as: 1 normal bowel wall, 2 subtle residual abnormality of the bowel wall, and 3 obvious residual tumor. All patients underwent flexible endoscopy Pentax Medical Netherlands, Uithoorn, The Netherlands of the rectum after a rectal phosphate enema. Only white light imaging was used with HDTV, and the images of the tumor area were digitally stored. CR was defined as the absence of residual tumor with only a flat, white scar with or without teleangiectasia Fig.

A small, flat ulcer with smooth edges without signs of residual polypoid tissue was considered to be a potential CR Fig. Every other type of ulcer or mass was considered as definite residual tumor Fig. A biopsy was only performed in equivocal cases, as judged by the surgeon during the endoscopy.

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Biopsy results that indicated tumor or high-grade dysplasia were considered proof of residual tumor. Absence of tumor or high-grade dysplasia in biopsy samples was not considered definite proof of CR because of the risk of sampling error.

T indicates tumor; arrows indicate scar or residual tumor after CRT. Patients imaged in d and e experienced sustained clinical CR at follow-up. Definitions of confidence level scores for assessment of complete response for every modality. All MRI examinations were performed at 1.

Additional axial diffusion-weighted images were obtained with b0 as the lowest and b as the highest b value. The sequence details are shown in Appendix.

An apparent diffusion coefficient ADC map was automatically calculated. DWI c revealed absence of diffusion restriction indicating CR. Histopathology of the total mesorectal excision TME resection specimen was used as the reference standard, with both high-grade dysplasia and carcinoma considered as residual tumor.

CR was defined as ypT0N0. Surgical specimens were evaluated according to the method of Quirke and Dixon. Receiver operator characteristics ROC curves were constructed with confidence levels to assess the diagnostic performance of clinical assessment and MRI. The areas under the ROC curve AUC with corresponding sensitivities and specificities were calculated for all modalities.Medically reviewed by Drugs. Last updated on May 1, Fludeoxyglucose F18 Injection is indicated for positron emission tomography PET imaging in the following settings:.

For assessment of abnormal glucose metabolism to assist in the evaluation of malignancy in patients with known or suspected abnormalities found by other testing modalities, or in patients with an existing diagnosis of cancer. For the identification of left ventricular myocardium with residual glucose metabolism and reversible loss of systolic function in patients with coronary artery disease and left ventricular dysfunction, when used together with myocardial perfusion imaging.

For the identification of regions of abnormal glucose metabolism associated with foci of epileptic seizures. Fludeoxyglucose F18 Injection emits radiation. Use procedures to minimize radiation exposure.

Guidelines and risk assesment models

Calculate the final dose from the end of synthesis EOS time using proper radioactive decay factors. Assay the final dose in a properly calibrated dose calibrator before administration to the patient [ see Description Within the oncology, cardiology and neurology settings, the recommended dose for adults is 5 — 10 mCi — MBq as an intravenous injection.

Within the neurology setting, the recommended dose for pediatric patients is 2. The optimal dose adjustment on the basis of body size or weight has not been determined [ see Use in Special Populations 8. These estimates were calculated based on human 2 data and using the data published by the International Commission on Radiological Protection 4 for Fludeoxyglucose 18 F. The dosimetry data show that there are slight variations in absorbed radiation dose for various organs in each of the age groups.

These dissimilarities in absorbed radiation dose are due to developmental age variations e. The identified critical organs in descending order across all age groups evaluated are the urinary bladder, heart, pancreas, spleen, and lungs.

Assumptions on the biodistribution based on data from Gallagher et al. Multiple-dose glass vial containing 0. Radiation-emitting products, including Fludeoxyglucose F 18 Injection, may increase the risk for cancer, especially in pediatric patients. Use the smallest dose necessary for imaging and ensure safe handling to protect the patient and health care worker [ see Dosage and Administration 2.

In the oncology and neurology setting, suboptimal imaging may occur in patients with inadequately regulated blood glucose levels. In these patients, consider medical therapy and laboratory testing to assure at least two days of normoglycemia prior to Fludeoxyglucose F 18 Injection administration. Hypersensitivity reactions with pruritus, edema and rash have been reported in the post-marketing setting. Have emergency resuscitation equipment and personnel immediately available. The possibility of interactions of Fludeoxyglucose F 18 Injection with other drugs taken by patients undergoing PET imaging has not been studied.

Animal reproduction studies have not been conducted with Fludeoxyglucose F 18 Injection. It is also not known whether Fludeoxyglucose F 18 Injection can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Consider alternative diagnostic tests in a pregnant woman; administer Fludeoxyglucose F 18 Injection only if clearly needed. It is not known whether Fludeoxyglucose F 18 Injection is excreted in human milk.

Consider alternative diagnostic tests in women who are breast-feeding. Use alternatives to breast feeding e. The safety and effectiveness of Fludeoxyglucose F 18 Injection in pediatric patients with epilepsy is established on the basis of studies in adult and pediatric patients. In pediatric patients with epilepsy, the recommended dose is 2. The optimal dose adjustment on the basis of body size or weight has not been determined.

In the oncology or cardiology settings, the safety and effectiveness of Fludeoxyglucose F 18 Injection have not been established in pediatric patients. Fludeoxyglucose F 18 Injection is a positron emitting radiopharmaceutical that is used for diagnostic purposes in conjunction with positron emission tomography PET imaging.