Nuclear Medicine

Nuclear Medicine

  • Judocus Borm added an answer:
    Could MIBI be the only gold standard to rule out arrythmia? Could this be done on ED's arrival?

    Arrythmia is easily identifiable by ECG (EKG). But it is always taken lightly considering the inconsistency and inconclusiveness of the ECG measurements. During patients' arrivals at ED, I saw few patients who were discharged after about 5 rounds of ECG. They were given the appointment to return for MIBI to confirm the aforementioned malady. Some just did not return as one way or another, they died on the next arrival at ED or none at all. Is there any alternative in-situ procedure(s) to help "prolong" their lives upon their ED's entrance?

    Judocus Borm · Reinier de Graaf Groep

    99mTc-sestaMIBI [MIBI] is a perfusion agent, arrythmia can also be caused by a number of causes that bear little relation with myocardial perfusion. So however MIBI [or for that matter: tetrofosmin] is actually used in any clinical protocol, it can never be used as a gold standard to rule out arrythmia irrespective of cause.

    In the physiology of the myocardial uptake of MIBI no hidden suggestion can be found that it is suited for arrythmia detection.

    A normal stress MIBI scan has only been shown to be associated with a good long term prognosis when used in patients who were suspected of having ischaemic heart disease. No such statements can be made for the use in patients with symptomatic arrythmia, without

    To my knowledge, when arrythmia in isolation is suspected a completely different diagnostic strategy is adhered to.

    So I think the question needs to be modified a little:

    Could MIBI be the only gold standard to rule out ischemia induced arrythmia?

    I think not, because in case of cardiac imaging, anything that can be done using 99mTc-sestaMIBI can also be done using 99mTc-tetrofosmin. Only a small adjustment of cut-off values suffices for any switch-over.

  • Judocus Borm added an answer:
    Do you have a design guide for a nuclear medicine rooms?

    I would like to design the building of department of nuclear medicine in a hospital. What I am looking for is finding a suitable design of location of rooms and laboratories and waiting areas in the building? I would like to have some maps for instance to use ideas of them on my map. Thanks.

    Judocus Borm · Reinier de Graaf Groep

    @ Dmitry Soloviev: The IAEA is an excellent starting point, but unfortunate not sufficient. Local legislation, compatebility with other rule-making and local practices do enter the design equotation.

    For example, the rules and regulations for keeping patients in isolation in Germany after radioiodine therapy necessitate over 2000 dedicated hospital beds, whereas The Netherlands can do with less than 100 beds. This extreme difference can not be explained by population size. Both countries have to apply the same rules under the EurATOM rules. This is a clear example that the IAEA is an excellent, but not sufficient and that large local differences exist.  

  • Hanno Krieger added an answer:
    Are there good documents for practical protection strategies in nuclear medicine buildings?

    For planning the building of nuclear medicine department in a hospital I need good documents. Who can help me to find them quickly?

    Hanno Krieger · retired from Justus-Liebig-Universität Gießen

    It´s no problem, IAEA report 1160.

  • Andrea F Armstrong added an answer:
    Does anyone know of any commercially available (gallium oxide) targets for producing Ge-68 on a cyclotron?

    Does anyone know of any commercially available (gallium oxide) targets for producing Ge-68 on a cyclotron? Preferably but not necessarily something that is compatible with a GE PET-Trace cyclotron?

    Andrea F Armstrong · McMaster University

    Thank-you so much, that is incredibly helpful!

    A

  • Nur Hidayati added an answer:
    I need internal dosimetry software for nuclear medicne. Can anyone provide me any software, except OLINDA/EXM (it's not available at the moment) ?

    I am interested to purchase an internal dosimetry software for nuclear medicine, but OLINDA/EXM is not available at the moment. Please advise me the similar software which I can use for calculation Internal Dosimetry in Nuclear Medicine?

    Nur Hidayati · Badan Tenaga Nuklir Nasional

    Thank you. I will look for it.

  • Gamal Abdul Hamid added an answer:
    What is the best imaging method to detect bone disease in multiple myeloma?

    At present there are several radiological methods and radioisotope available, but what is the most effective in detecting bone disease in multiple myeloma?

    Gamal Abdul Hamid · Aden University

    Besides conventional radiography,  whole-body low-dose computed tomography (CT), whole-body magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT are considered for the diagnosis of osseous and extraosseous manifestations of MM.

  • Sune Høgild Keller added an answer:
    What is a suitable method to calculate the uptakes in nuclear medicine form PET or SPECT images quantitative?

    How can we calculate the uptakes from the images in PET/SPECT images? Is there any available MATLAB toolbox or software?

    Sune Høgild Keller · Rigshospitalet

    I have used Vinci as well and is good for DICOM if you only have a few data sets. For larger DICOM data sets Osirix is better as it has a database as well.

    But for odd data formats and  phantom data ets Vinci is by far the best tool.

  • Reina Jimenez added an answer:
    Has anyone experienced better dosimetric outcomes with symmetric planning in LDR prostate brachy?

    Is there any literature evidence on symmetric planning and its advantages over asymmetric planning in ldr brachy. Thanks

    Reina Jimenez · Clinica Santiago de Leon, Caracas

    After more than 600 patients implanted one thing is certain to me: Each prostate is unique, and despiting more of them are symetric in their external aspect, internal composition,  drive by biopsy results,  made us to plan almost symetric distributions of needles but asymetric distribution of dose. One of the wonders of brachytherapy is the power of intensity modulated therapy design for each prostate form and content.. We also use 0.496 U and D90 is ever greater than planned. More dose in Ca nodules, better local control. All of this happened inside the gland. D90 must ever respect  margins 2-3 mm for rectal wall,  up to 4 mm  outside the capsule in the rest of the gland  

  • Madhur KUMAR Srivastava added an answer:
    Should Cardiac SPECT or coronarography be performed first to distinguish coronary disease?

    Nuclear medicine physicians and cardiologist have disagreement in time of application of cardiac SPECT and coronarography in cases suspected for coronary disease.

    Nuclear physicians consider that cardiac SPECT is one non invasive method with very high efficiency for detection of coronary disease.

    Cardiologists consider that cardiac SPECT is not sufficient for detection of coronary disease and prefer coronarography as first diagnostic method   

    Madhur KUMAR Srivastava · Jawaharlal Institute of Postgraduate Medical Education & Research

    The choice of test should depend on many things like presenting symptoms, time since start of symptom, associating co-morbidities to name a few.

    In case of classical MI symptoms presenting within the golden hour, angiography followed by definitive management (Stenting/CABG) is the treatment of choice. However, the condition is different with patients who present after 12 hours or present with atypical symptoms or who are diabetic and give history of similar episodes in past or previous CAD patients presenting with new symptoms. In all these cases, it is imperative to know the status of myocardium at risk - whether viable or scarred. So viability study should be done before planning management. In case of only scarred tissue, no need for aggressive surgical management as it would not help the patient, manage it medically, however, if viable myocardium is present, definitely go for surgical management. 

    In patients who have atypical chest pain or have inconclusive TMT, again there is controversy on choice of test, but if Stress Cardiac SPECT study is done and it is normal i.e. there is no evidence of stress induced myocardial ischemia, then we can assure the patient that if the maintain their life style, the chance of having MI in next one year is <1%.

  • Gran Badshah added an answer:
    Which softwares are able to replace a voxel value by another one in a SPECT acquisition ? (files in DICOM format)
    i.e.: replace some hot spots (> X counts/vol unit) by a mean value.
    Gran Badshah · Universiti Malaysia Pahang

    Hi dears, please can any one help me how to write watermarked frames to a DICOM image back to hide watermarks to be ready for communication?

  • Ronnie C Mease added an answer:
    Does anyone have good comments about Cell tracking with nanoparticles or radiolabeling the cells?

    Does anyone have good comments about Cell tracking with nanoparticles or radiolabeling the cells?

    Ronnie C Mease · Johns Hopkins Medicine

    In-111 oxine and Tc-99m HMPAO are two radiopharmaceuticals that are used clinically to tag white blood cells ex-vivo for reinjection into patients. There are commercial cell membrane intercalating dyes that can be used for optical imaging. There are numerous radiolabeled cell membrane intercalating dyes and phospholipid analogs that also can tag cells. All of these methods have pros and cons which will depend on your particular application.

  • Lina Jia added an answer:
    Why will 18F- combine with the Al-NOTA complex instead of combining with free Al3+? And why 18F- is not free in [18F]AlF complex?


    Why 18F- will combine with the Al-NOTA complex instead of combining with free Al3+ in the method for 18F-labeling of peptides using [18F]AlF (aluminum fluoride) complex formation with 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) derivatives? And why 18F- is not free in [18F]AlF complex?

    Thanks!

    Thanks ! I have learned a lot.

  • What is the difference in parathyroid hormone (PTH) suppression activity between Calcium Carbonate and Calcium Citrate?

    As we know the intake of calcium supplement gradually improves the plasma calcium level and thus suppressing parathyroid secretion. Is there any definite value in what extent calcium carbonate and calcium citrate varies in view of PTH suppression?

  • Teik Hin Tan added an answer:
    Can anyone share with me their experience in paediatrics dose of radioiodine treatment in differentiated thyroid cancer?

    I tried to use the few suggestion of peadiatrics dosing of RAI treatment in the ATA and EANM guidelines. I realised that there was a wide range of dosing after using those suggestion. Please help. Thank you. 

    Teik Hin Tan · National Cancer Institute, Malaysia

    Thanks Dr Lena. We have quite a number of patients in this age group. And, I do agree on giving radioiodine if tumour is >1.0cm. Because, in my experience, almost all patients demonstrated metastasis either lymph node or lungs on our first initial radioiodine whole body scan. They all received radioiodine treatment. Some responded but some were not that lucky. But, both of the two groups were well during follow up until adulthood. It seems likely that radioiodine improves survival outcome in these two groups. Anyway, these patients usually have very good prognosis and long survival whether metastases or not. So, it is very difficult to carry out such cohort.

  • Negri Roberto added an answer:
    Is it possible to conjugate DOTA with DOX (doxorubicine) and under which condition?
    Bioconjugation of bifunctional chelate DOTA with DOX.
    There is increasing interest in the bio-conjugation of peptides and antibody with bi functional chelating agent (DOTA, DTPA), used for RRNT and RIT.

    Is it possible to conjugate DOTA with DOX (doxorubicine) and under which condition?
    Negri Roberto · Amedeo Avogadro University of Eastern Piedmont

    It depends what functional group of DOX you want to use to make the bond... If the amino group is your choice, then you just need to use your DOX with any DOTA-like compound with a functional group that reacts with amines (DOTA-SA or DOTA with isothiocyanate mojety). You could find protocols for these reactions in the literature

  • Madhur KUMAR Srivastava added an answer:
    What is the lowest applicable activity with the earliest imaging time for sentinel node biopsy for breast cancer?

    Research for "easy to do Nuclear Medicine with low dose culture"

    Madhur KUMAR Srivastava · Jawaharlal Institute of Postgraduate Medical Education & Research

    Usually for sentinel node biopsy with surgery to be done same day, 20 MBq is adequate and should be injected at least 2 hours before the surgery. If surgery is planned the next day , then 37-100 MBq is recommended.

    It depends on center to center on type of injection, usually we prefer peri-areolar as peritumoral lymphatics may be heavily laden with tumoral cells so that lymphatics might not flow leading to failure of technique. Peri-areolar injection concept has come up because of unique nature of superficial lymphatics of breast (Sappy plexus).

    Imaging before the surgery, again varies between various centers depending on the time at your disposal. In many busy centers, they do not do imaging and send the patient directly for surgery, but in my opinion, we should do planar imaging and in doubt SPECT- CT for confirmation.

    During surgery, with the use of gamma probe, the injection site is marked and any node having more than 10% of injection site count is considered as positive. This should be taken out for frozen section. Again whole axilla should be surveyed for activity and same principle of 10% should be followed till we do not find anything more than background.

    Hope this would help...Best of luck

  • Jacek Koziorowski added an answer:
    Is it feasible to couple sestamibi (nuclear medicine) with magnetic particles?
    If so, any suggestions on how to couple them?
    Jacek Koziorowski · University Hospital Linköping

    If you look on the structure of sestamibi; a small microsphere - and want to coulpe it to a SPION - my guesstimate is that the biological property of Sestamibi (a MPI agent) will be lost. It is like attaching a car to a corn flake and hope to use it in the cereal for breakfast.

  • After injecting 99mTc-MIBI how much activity (MBq/ml or mCi/ml) is absorbed by a typical myocardium at peak absorption?

    As far as I know, within several min after injection activity absorption would be in the highest value possible. What is "the" value in (Mbq/ml or mCi/ml) ?

    F. Javier de Haro-del Moral · Hospital Universitario Puerta de Hierro-Majadahonda

    The uptake in myocardium in only 2-3%

  • Rame Miftari added an answer:
    What are the advantages of cardiac dynamic SPECT imaging over static (conventional) SPECT imaging?

    In some papers they say dynamic SPECT provides a better contrast between normal and decreased flow regions than can be obtained from static imaging. what are the other advantages,if any?

    Rame Miftari · UNIVERSITY CLINICALE CENTER OF KOSOVA

    The advantage of cardiac dynamic SPECT imaging over conventional SPECT imaging is that cardiac dynamic SPECT imaging allow to estimate the absolute kinetic parameters of left ventricle.
    Dynamic SPECT didn't mean "gated SPECT". In dynamic SPECT the data are collected in time of dose administration.

  • Hanno Krieger added an answer:
    Why internal dosimetry in nuclear medicine is not taken as seriously by doctors as in radiotherapy?
    Prof. Dr. Ljungber, Dr. Stabin, Dr. Flux, Dr. Celler, Dr. Simpkin, Dr. Zazonico, Dr. Sgouros, Dr. Cremonesi, and many others Authors published a lot of papers, softwares, etc. Even so, very few centers apply internal dosimetry for nuclear medicine therapy. Why?
    Hanno Krieger · retired from Justus-Liebig-Universität Gießen

    Most has been said. I just want to show my experience. If you try to calculate doses, organ doses and especially effective doses, you must exactly know the volume and tissue of distribution. This issue is quite impossible, because each patient shows his own metabolism, anatomy and radio nuclide distribution. 

    Therefore doses are normally calculated by human models with standardised persons. The results can just give some ideas of the radiation exposition of the patients.

    A short remark to the diagnostic use of 131-Iodine. It´s completely out and has been substituated in mots cases to 99m-Tc compounds, which serve in same quality but minimize the dose to the patient. The same holds for 201Tl, it´s replaced for cardiac test by 99mTc (MIBA).

  • Alejandro sanchez crespo added an answer:
    In PET images, with the current methods of reconstruction, it is still a necessary denoising step?
    If so, what is the most common method for denoising?
    Alejandro sanchez crespo · Karolinska University Hospital

    Not necesary. One can use different filtration methods or even more advance techniques like waveletes but in clinical routine we do not denoise PET images before reconstruction.

  • Stephan Nekolla added an answer:
    What are the real values of cardiac kinetic parameters washin(k1) and washout(k2) for a normal myocardium?

    When using a two compartmental model

    Stephan Nekolla · Technische Universität München

    In addition to the aforementioned complexities, K1 varies vastly for different (radio)-tracers which are linked to the clinical target, namely the myocardial blood flow - if one uses the Renkin-Crone equation  K1 = E*MBF, E = (1-exp(-PS/MBF)). In other words, for a normal MBF of 0.8, K1 could be 0.8 for 15-O water, 0.75 for N-13 ammonia or 0.5 for 82-Rb (numbers gut feeling...) - depending on the extraction fraction (E) of the particular tracer.

  • Atena Aghaei added an answer:
    What is the lowest applicable activity with the earliest imaging time for sentinel node biopsy for breast cancer?

    Research for "easy to do Nuclear Medicine with low dose culture"

    Atena Aghaei · Mashhad University of Medical Sciences

    we use about 20 MBq for the same day surgery , peri-areolar, intradermal injection, near the tumor side, and we have had good results.

  • Dirk Rattat added an answer:
    What is the acceptable volume (in ml) of Technetium-99m that can be administered to rats?
    I want to tag my extract with technetium-99m and administer it in to the rats tail vein for bioavailability study in rats, but i am finding it difficult to know the volume to administer to the rats.
    Dirk Rattat · Umicore

    Minor remarks:

    "I want to use Tc-99m for Imaging as well as "cut and count assay". is it possible?"

    Perfectly possible. For a reliable procedure make sure not to loose urine, e.g. during scanning (tissues to collect it). Especially when injecting higher volumes, this may happen frequently and can ruin results.

    If the Tc-99m activity of your sample is too low, you can always consider concentrating (depending on the labelled molecule e.g. with spin colums when working with bigger labelled molecules) rather than increasing the volume to inject.

    (Finally, don't forget to have an eye on the pH of your solution, but that's clear anyway.)

  • Yónatan Calderón Pérez added an answer:
    Can multiple radio-labeled probes be used at the same time for PET imaging?
    If different isotopes (11-C, 89-Zr, 64Cu) are used to label different antibodies, can they all be used at the same time during PET imaging? Or because all of them undergo Beta+ decay and produce Gamma rays, is it not possible to distinguish between signals coming from the different probes?
    Yónatan Calderón Pérez · Autonomous University of Barcelona
    Hi Virginia.

    In the case of PET, as many of my coleages pointed out, it is not possible to distiguish the gamma photons emited by the different radiotracers. The reason is that all of them share the same energy (511 keV).

    In the case of SPECT it may be possible. But in most of the cases, it is not. The reason is the energy resolution of the scintillator crystals (>10% FWHM). This low energy resolution does not allow to discard scatter events which can amount up to 50% of your signal (and that is using a single radiotracer, imagine using multiple).

    By using semiconductor detectors (Ge,Si,CdTe,...) it is possible to distinguish radiotracers with different energies and use them simultaneously in the case of SPECT or Compton camera.

    Here is a link to an article of the 2007 IEEE NSS/MIC conference where multiple radiotracers are used simultaneously with a mouse. The scanner is a prototype Compton camera.
  • Manish K. Mishra added an answer:
    Why is Radon-222 itself a gas but its decay products solids?
    see above
    Manish K. Mishra · Department of Atomic Energy
    Radioactivity is a nuclear phenomena. It is number of protons in the nucleus which decides the 'State' of that element. An element can naturally exist in Solid, Liquid or Gas state. So, if by any means the number of protons in the nucleus varies ( be it by Alpha or Beta emission or by EC), the state of the element can also vary. Solid elements can change into Gas/Liquid or Gaseous ones into Solid/Liquid by radioactive transformation.
  • Carl A Wesolowski added an answer:
    What is the value of predictions in nuclear studies?
    Monte Carlo simulations to predict experimental data in the costly nuclear experiments!
    Carl A Wesolowski · University of Saskatchewan
    For modeling in general, one has data, and in some sense application of a model to the data extracts features from that data that have should have physical meaning. If we have done everything correctly, the difference between the model and the data should be at the noise limit of the data. It is generally assumed that models that have less than 10% relative error of fitting are good models, although frankly, noise levels are closer to 1% for nuclear studies, and most models are not very good ones.

    Concerning prediction, a very good model has predictive ability only if it has been designed for the prediction of a particular thing. This may seem somewhat confusing. Let us consider ordinary least squares in y of a functional model of concentration in time to some data. If we have measurement time intervals that are exact and invariant, like 1, 2, 3, 4,,,,n-1,n minutes, then we can predict the n+1 st concentration without regression error, and the only error would be modeling error and data noise. However, if we measure concentrations at unequal time intervals, like 5, 7, 11, 20, 23, 30,,,n-1,n. Then ordinary least squares regression yields a prediction tor concentration at the n+1 time that is too large, and the regression equation slope will be too shallow.

    There are many other examples of error types. Consider for example, that we may not be modeling what we think we are. If we model concentration of a bolus IV injected agent, it is common to assume that we are modeling concentration by ordinary least squares fit of an exponential decay function to that concentration.

    The first error results from the concentration being zero initially, but our model, the exponential decay, is maximum at that time. It would be better to model the concentration as the convolution of a vascular model and a parenchymal model, which then allows one to have both Cobs(t=0)=0 for the concentration and C(t=0)=maximum for the parenchymal model.

    The second error results from assuming an exponential shape where no such thing occurs. An exponential shape does not conserve mass. It comes from C'(t)=-CL*C(t), which is incorrect since C'(t) not only clears (CL) but also dilutes in parencyhmal fluid, and so if the clearance is only renal, then M'(t)=-CL*C(t), which latter is the urinary definition of clearance, and C'(t)>M'(t) leading to inflated CL values, which are even more inflated when there is excess fluid, i.e., when parenchymal fluid is increased in amount.

    Suppose we want to fit this concentration data to find clearance, how do we fit it? As it turns out ordinary least squares would do a poor job of measuring clearance, better would be to use weighted least squares where we minimize Norm[{k*Cobs(t)-C(t)}/{k*Cobs(t)}, best would be to minimize SD(CL)/CL. i.e., it is best to minimize the error of the quantity we wish to measure. Next, it is better to use a fit function that has a shape parameter rather than a fixed, incorrect shape, i.e. a gamma variate rather than an exponential.

    Fine suppose that gets us clearance. Does it get us a model for concentration? No, a concentration model would a convolution of a vascular first pass model, like a gamma distribution and a parenchymal impulse response like a different gamma distribution. Such a model would be expected to match concentration to approximately the level of the noise in the data, e.g., 1%. But, it would not be a model of Clearance. Only the second part of it, the parenchymal impulse response would relate to clearance.

    In summary: 1) The art of finding answers in data is often an inverse problem requiring extensive use of numerical methods chosen for definite reasons, and not chosen by reason of the accidental familiarity to the reader of such methods.
    2) Physical equations must be used, like those that conserve mass, have correct units that balance.

    Using these above principles, predictions and extrapolations can be made accurately, if that is made the explicit purpose of modeling. To do so, requires enough numerical tools in the hands of the modeler, that the correct ones can be discovered by a combination of theory and goodness of fit testing. Moreover, it can take years to solve any single problem type, and there are too few reviewers who can even read the results of such material.
  • Joern Nybo Fog added an answer:
    Where to find a new state of the art nuclear medicine department?
    I have a project establishing a new state of the art nuclear medicine department inclusive at new radiopharmaceutical laboratory and a clean room for blood labeling. The department will have 3 PET/CT, 3 SPECT/CT, 1-2 dedicated cardiac gamma camera and 1 mobile gamma camera.

    The department will have about 30 employees technicians, physicians and a physicist.
    So my question is, does anyone know where to visit a modern, state of the art and productive nuclear department?
    Joern Nybo Fog · Medical Institute, Region southdenmark
    Than you Marco, Swen, Willy and Niels.
  • Radu A. Vasilache added an answer:
    Is nuclear medicine beneficial in the long period?
    For quick recovery we are using nuclear medicine. Experts should handle otherwise these technologies are more harmful than beneficial.
    Radu A. Vasilache · Canberra Packard CE GmbH
    Nuclear medicine is not really used for quick recovery. It is used in two instances:
    1. for diagnostic (SPECT, PET, old fashioned scintigraphy...), and it is used because some of the techniques are simply the best way for identifying a condition
    2. for therapy of cancer, when we speak about metabolic radiotherapy, but this is not leading to quick recovery.
    For the diagnostic, the doses are higher than in classic radiology, but to the best of my knowledge there is no evidence that SPECT or PET investigations resulted in increased incidence of secondary cancers.
    For metabolic radiotherapy, the dose is lower than when using external radiotherapy and even much better localised and targeted, so in fact it saves dose to the patient.
    Summing all this, I would say developing a nuclear medicine program saves lives, either through precise diagnostic or through therapy.
  • Maria Lyra added an answer:
    Does anyone know how to obtain the S factors tables for S factors for 67Ga, 111In and Holmium 166?
    The new version, not the one which was calculated in 1975 and printed in MIRD Pamphlet11.
    Maria Lyra · National and Kapodistrian University of Athens
    Try the http://www.doseinfo-radar.comor Olinda or the older one mirdose 3.1 and you can calculate S

About Nuclear Medicine

A specialty field of radiology concerned with diagnostic, therapeutic, and investigative use of radioactive compounds in a pharmaceutical form.

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