DOCSLIB.ORG

Normal and Abnormal Patterns of Tc Pertechnetate Distribution In

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Normal and Abnormal Patterns of Tc Pertechnetate Distribution In Normal and Abnormal Patterns of 99mTc Pertechnetate Distribution in Meckel’s Scans Educational Robert Huynh, PharmD; Jorge Oldan, MD; Mitchel Muhleman, MD; Eric Smith, PharmD; Amir H. Khandani, MD Exhibit UNC School of Medicine Radiology Department Nuclear Medicine Division University of North Carolina at Chapel Hill, NC Introduction 99mTc Pertechnetate Scintigraphy Delayed Clearance Discussion Next Steps The Meckel’s scan is well-regarded for its straightforward execution, Physical Properties A. 14 y/o M B. 16 y/o M C. 33 m/o M D. 19 y/o F • Other mechanisms outside of colloid formation and labeling of blood Formal IRB-Approved Investigation simple radiopharmaceutical preparation, and high diagnostic accuracy. constituents may account for the observed anomalies. For example, • Abnormal 99mTc pertechnetate distribution has been observed in The fact that the procedure only requires 99mTc pertechnetate, eluted 99m In the decay of 99mTc, use of bacteriostatic saline as diluent can lead to increased activity in Tc (t1/2 = 6.01 h) 0.1427 several other patients at our institution. directly from the generator and free of any additional radiochemical three gamma (γ) muscle, liver, and/or blood pool.8 However, our pharmacy only uses processing, would suggest that abnormal patterns of radiotracer γ1 photons are released preservative-free saline. • Exploratory study (retrospective chart review) underway to identify 0.1405 distribution should not be expected. However, we have observed with energies of 0.0022 • With QC testing demonstrating low quantities of hydrolyzed- other potential contributing factors. 99m Select cases of delayed clearance observed during Meckel’s scans at our abnormal patterns of Tc pertechnetate distribution with instances of MeV (γ1),0.1405 MeV reduced technetium (<1% per elution), it is an unlikely contributor to Intra- and Inter-Patient Correlations γ3 (γ ), and 0.1427 MeV institution. On static delayed images, diffuse activity is still prominent delayed clearance from the liver and cardiac blood pool. Beyond the γ 2 the observed pattern of distribution. 99m 2 • Meckel’s scan, Tc pertechnetate is extensively utilized in nuclear (γ3). The most in the liver (patients A – D) and cardiac blood pool (patients B – D) at 15 Intra-patient: patient D with two Meckel’s scans spaced 3 months 99m • Labeling of RBCs or another blood component cannot be ruled out 99m medicine, making it even more important to recognize the possibility of abundant of these, γ2, minutes. In a typical pattern of Tc pertechnetate distribution, the apart showing similar patterns of Tc pertechnetate distribution. and would account for both blood pool and liver activity; possible its altered biodistribution and delayed clearance 99 5 accounts for 89% of all tracer rapidly clears from the liver and blood pool after distribution Refutes the idea that the issue is related to product quality. Tc (t1/2 = 2.11 x 10 y) 0.0 (within several minutes) due to lack of uptake. mechanisms for blood labeling are observed in each patient: nuclear transitions. • Inter-patient: diverging patterns of distribution (i.e. one normal, one 99m Objectives Root Cause Analysis − Patient A takes a lipophilic drug capable of crossing the blood-brain abnormal) between two Meckel’s patients receiving the same Tc Biodistribution barrier (BBB), and likely erythrocyte membranes as well. However, the pertechnetate lot would lend additional support against QC issues. Identifying possible causes of delayed clearance in liver and cardiac case report by Vento et al. involved significant polypharmacy, where However, no such cases have yet been observed. 1) Summarize the etiology, epidemiology, and pathophysiology of 99mTc is collected from the 99Mo generator in the chemical 12 blood pool might reasonably begin with consideration of known multiple lipophilic medications were identified. This may be Meckel’s diverticulum. form of NaTcO (sodium pertechnetate). Pertechnetate has • Similar cases to be reviewed. 4 techniques for visualizing these targets. important in providing a significant source of metal ions or other points 2) Describe the normal, physiologic patterns of radiotracer an atomic radius comparable to iodide and, when of attachment for pertechnetate within the RBC. distribution after intravenously administered 99mTc pertechnetate. administered intravenously, distributes primarily to the Agent Mechanism − Patient B received a dextrose infusion prior to the Meckel’s scan and Conclusion thyroid, salivary glands, choroid plexus, bladder, and 3) Discuss the pathophysiologic basis for 99mTc pertechnetate uptake 99mTc SC Phagocytosis of colloidal particles by macrophages takes a lipophilic medication capable of penetrating the BBB. Also • 99mTc pertechnetate accumulates in gastric tissue and can be used to stomach. Liver takes two medications containing aluminum in color additives. in Meckel’s diverticulum. (sulfur colloid) (Kupffer cells) of reticuloendothelial system. identify Meckel’s diverticula with ectopic gastric mucosa. It should Since it accumulates in the mucoid cells of gastric mucosa, 99mTc RBCs; Visualization of labeled blood component’s − Patient C takes several lipophilic drugs and two medications not demonstrate persistent liver or cardiac blood pool activity. 4) Recognize cases of abnormal 99mTc pertechnetate distribution and Blood pertechnetate is useful in detecting Meckel’s diverticulum 99mTc HSA (albumin) dispersion through vasculature and heart chambers. containing aluminum in color additives. • clearance in Meckel’s scans. when it contains functional ectopic gastric tissue.1 Gastric Since Meckel’s diverticulum can occur anywhere in the abdomen, − Patient D received a dextrose infusion and two lipophilic drugs. activity in the cardiac blood pool and liver may interfere with the 5) Identify potential causes of abnormal 99mTc pertechnetate uptake can be increased via premedication with agents The agents listed provide clues to the nature of the potential cause(s) – 99m − Tin was not identified as an excipient in any of our patients’ interpretation of a 99mTc pertechnetate scan. distribution and clearance in Meckel’s scans. including H2R antagonists and pentagastrin. namely, 1) liver activity may be due to presence of a Tc-associated medications. None of the patients had received tin-containing colloidal impurity, and 2) inadvertent labeling of any blood component • Quality control of radiopharmaceuticals is critical in a nuclear The estimated sensitivity and specificity of this procedure 99m radiopharmaceuticals for a prior study. Biodistribution of with Tc would contribute to blood pool activity. Various mechanisms, 99m 4 medicine clinic and can quickly rule out causes when problems arise. Tc pertechnetate. in detecting Meckel’s is 89.6% and 97.1%, respectively. 2 Meckel’s Diverticulum in turn, may account for these processes. − None of the patients were on antimicrobial therapy at the time of study. • Lipophilic medications seems to be a common factor in our case series, but our series is small. It is possible that no single factor can An outpouching of the ileum first described in 1812 by Case Study Colloidal Hydrolyzed-reduced (HR) technetium: an insoluble colloid German anatomist Johann Friedrich Meckel.1 impurities resulting from radiolytic decomposition or reduction and Other Drug-Pertechnetate Interactions13,14 explain all cases of abnormal distribution. disproportionation of 99mTc. However, daily quality control (QC) Patient background: 8 month old female with hx of BRBPR. • tests demonstrate presence of HR species to be less than 1%. Note: several drug-pertechnetate interactions are outside the context Alternatively, this phenomenon might be the result of a complex Occurs when the omphalomesenteric (vitelline) duct Dose: 1.1 mCi 99mTc pertechnetate of Meckel’s diverticulum and are not presented here. interplay between several different factors, some of which may as fails to completely regress during gestation. yet be unidentified. Imaging: Anterior and posterior projections of the abdomen and Aluminum: complexation with pertechnetate leading to blood Blood tags Potentially Useful 99m pelvis, up to 30 minutes. pool retention. Daily QC tests demonstrate aluminum levels to Cimetidine (H2RA), Pentagrastrin • That Tc pertechnetate is extensively utilized in nuclear medicine Occurs in approximately 2% of the population and Increase pertechnetate accumulation in gastric parietal cells. underscores the importance of understanding its distributional is twice as common in males.1 be far below USP limits (10 ug/mL), but alternatives sources of Findings: On the static delayed images, activity is seen in the stomach aluminum are possible (e.g., Mylanta).5 behavior and diverse interactions with drugs and pathophysiology. at approximately 10 minutes with activity progressing into the proximal Glucagon 99m May be silent or symptomatic; the latter most small bowel. There is a focus (arrows) of increased radiotracer uptake Stannous (tin) ion: required for reduction of Tc and subsequent labeling Reduces peristaltic movement in the region around potential References commonly presents in children. in the abdomen just to the right of midline superior to the bladder, of RBCs, albumin, or another blood component. Tin from any external source, Meckel’s diverticulum to enhance pertechnetate accumulation. including prior administration of radiopharmaceuticals, may alter the 1. Irvine I, Doherty A, Hayes R. Bleeding meckel's diverticulum: A study of the accuracy of pertechnetate
Load more

Recommended publications
  • Novel Application of Quantitative Single-Photon Emission Computed
    Original Article | Nuclear Medicine https://doi.org/10.3348/kjr.2017.18.3.543 pISSN 1229-6929 · eISSN 2005-8330 Korean J Radiol 2017;18(3):543-550 Novel Application of Quantitative Single-Photon Emission Computed Tomography/Computed Tomography to Predict Early Response to Methimazole in Graves’ Disease Hyun Joo Kim, MD1, 2, Ji-In Bang, MD1, Ji-Young Kim, MD, PhD1, Jae Hoon Moon, MD, PhD3, Young So, MD, PhD4, Won Woo Lee, MD, PhD1, 5 Departments of 1Nuclear Medicine and 3Internal Medicine, Seoul National University Bundang Hospital, Seoul National University College of Medicine, Seongnam 13620, Korea; 2Department of Molecular Medicine and Biopharmaceutical Sciences, Graduate School of Convergence Science and Technology, Seoul National University, Suwon 16229, Korea; 4Department of Nuclear Medicine, Konkuk University Medical Center, Seoul 05030, Korea; 5Institute of Radiation Medicine, Medical Research Center, Seoul National University, Seoul 08826, Korea Objective: Since Graves’ disease (GD) is resistant to antithyroid drugs (ATDs), an accurate quantitative thyroid function measurement is required for the prediction of early responses to ATD. Quantitative parameters derived from the novel technology, single-photon emission computed tomography/computed tomography (SPECT/CT), were investigated for the prediction of achievement of euthyroidism after methimazole (MMI) treatment in GD. Materials and Methods: A total of 36 GD patients (10 males, 26 females; mean age, 45.3 ± 13.8 years) were enrolled for this study, from April 2015 to January 2016. They underwent quantitative thyroid SPECT/CT 20 minutes post-injection of 99mTc- pertechnetate (5 mCi). Association between the time to biochemical euthyroidism after MMI treatment and %uptake, standardized uptake value (SUV), functional thyroid mass (SUVmean x thyroid volume) from the SPECT/CT, and clinical/ biochemical variables, were investigated.
    [Show full text]
  • Fate of Sodium Pertechnetate-Technetium-99M
    JOURNAL OF NUCLEAR MEDICINE 8:50-59, 1967 Fate of Sodium Pertechnetate-Technetium-99m Dr. Muhammad Abdel Razzak, M.D.,1 Dr. Mahmoud Naguib, Ph.D.,2 and Dr. Mohamed El-Garhy, Ph.D.3 Cairo, Egypt Technetium-99m is a low-energy, short half-life iostope that has been recently introduced into clinical use. It is available as the daughter of °9Mowhich is re covered as a fission product or produced by neutron bombardement of molyb denum-98. The aim of the present work is to study the fate of sodium pertechnetate 9OmTc and to find out any difference in its distribution that might be caused by variation in the method of preparation of the parent nuclide, molybdenum-99. MATERIALS & METHODS The distribution of radioactive sodium pertechnetate milked from 99Mo that was obtained as a fission product (supplied by Isocommerz, D.D.R.) was studied in 36 white mice, weighing between 150 and 250 gm each. Normal isotonic saline was used for elution of the pertechnetate from the radionuclide generator. The experimental animals were divided into four equal groups depending on the route of administration of the radioactive material, whether intraperitoneal, in tramuscular, subcutaneous or oral. Every group was further subdivided into three equal subgroups, in order to study the effect of time on the distribution of the pertechnetate. Thus, the duration between administration of the radio-pharma ceutical and sacrificing the animals was fixed at 30, 60 and 120 minutes for the three subgroups respectively. Then the animals were dissected and the different organs taken out.Radioactivityin an accuratelyweighed specimen from each organ was estimated in a scintillation well detector equipped with one-inch sodium iodide thallium activated crystal.
    [Show full text]
  • Package Insert TECHNETIUM Tc99m GENERATOR for the Production of Sodium Pertechnetate Tc99m Injection Diagnostic Radiopharmaceuti
    NDA 17693/S-025 Page 3 Package Insert TECHNETIUM Tc99m GENERATOR For the Production of Sodium Pertechnetate Tc99m Injection Diagnostic Radiopharmaceutical For intravenous use only Rx ONLY DESCRIPTION The technetium Tc99m generator is prepared with fission-produced molybdenum Mo99 adsorbed on alumina in a lead-shielded column and provides a means for obtaining sterile pyrogen-free solutions of sodium pertechnetate Tc99m injection in sodium chloride. The eluate should be crystal clear. With a pH of 4.5-7.5, hydrochloric acid and/or sodium hydroxide may have been used for Mo99 solution pH adjustment. Over the life of the generator, each elution will provide a yield of > 80% of the theoretical amount of technetium Tc99m available from the molybdenum Mo99 on the generator column. Each eluate of the generator should not contain more than 0.0056 MBq (0.15 µCi) of molybdenum Mo99 per 37 MBq, (1 mCi) of technetium Tc99m per administered dose at the time of administration, and not more than 10 µg of aluminum per mL of the generator eluate, both of which must be determined by the user before administration. Since the eluate does not contain an antimicrobial agent, it should not be used after twelve hours from the time of generator elution. PHYSICAL CHARACTERISTICS Technetium Tc99m decays by an isomeric transition with a physical half-life of 6.02 hours. The principal photon that is useful for detection and imaging studies is listed in Table 1. Table 1. Principal Radiation Emission Data1 Radiation Mean %/Disintegration Mean Energy (keV) Gamma-2 89.07 140.5 1Kocher, David C., “Radioactive Decay Data Tables,” DOE/TIC-11026, p.
    [Show full text]
  • Loss of Pertechnetate from the Human Thyroid
    LOSS OF PERTECHNETATE FROM THE HUMAN THYROID J. G. Shimmins Regional Dept. of Clinical Physics and Bioengineering, Western Regional Hospital Board, Glasgow, Scotland R. McG. Harden and W. D. Alexander University Department of Medicine, Western Infirmary, Glasgow, Scotland The pertechnetate ion, like the iodide ion, is Magnascanner V (3,6) were started immediately trapped by the thyroid gland (1 ). Several authors after injection and were continued for 45 mm when have claimed that pertechnetate is not bound in the five scans had normally been completed. The scan thyroid (2) and that the gland behaves as a single speed was 100 cm/sec, and the line spacing was compartment (3) . However, the finding of organic 1 cm. Venous blood samples were taken at 2, 8, 15, binding of 9DmTcin rats (4,5) raises the question 30 and 45 mm. One gram perchlorate was given of whether some such binding may not occur in man. orally as a crushed powder in nine subjects 50 mm In this study we have investigated the binding of after the intravenous administration of pertechne pertechnetate in the human gland by measuring the tate. The same amount was given orally to the re rate of pertechnetate discharge from it after per maining four 3 hr after intravenous administra chlorate administration and have compared this rate tion of pertechnetate. Scans were carried out for an of discharge with the normal loss rate of pertechne additional 45 min after perchlorate administration, tate from the thyroid (3). If pertechnetate is Un and blood samples were taken at 2, 8, 15 and 45 bound, it should be possible to discharge it from min.
    [Show full text]
  • Radionuclide Thyroid Scans
    Radionuclide Thyroid Scans Report 2003 1 Purpose The purpose of this guideline is to assist specialists in Nuclear Medicine and Radionuclide Radiology in recommending, performing, interpreting and reporting radionuclide thyroid scans. This guideline will assist individual departments in the formulation of their own local protocols. Background Thyroid scintigraphy is an effective imaging method for assessing the functionality of thyroid lesions including the uptake function of part or all of the thyroid gland. 99TCm pertechnetate is trapped by thyroid follicular cells. 123I-Iodide is both trapped and organified by thyroid follicular cells. Common Indications 1.1 Assessment of functionality of thyroid nodules. 1.2 Assessment of goitre including hyperthyroid goitre. 1.3 Assessment of uptake function prior to radio-iodine treatment 1.4 Assessment of ectopic thyroid tissue. 1.5 Assessment of suspected thyroiditis 1.6 Assessment of neonatal hypothyroidism Procedure 1 Patient preparation 1.1 Information on patient medication should be obtained prior to undertaking study. Patients on Thyroxine (Levothyroxine Sodium) should stop treatment for four weeks prior to imaging, patients on Tri-iodothyronine (T3) should stop treatment for two weeks if adequate images are to be obtained. 1.2 All relevant clinical history should be obtained on attendance, including thyroid medication, investigations with contrast media, other relevant medication including Amiodarone, Lithium, kelp, previous surgery and diet. 1.3 All other relevant investigations should be available including results of thyroid function tests and ultrasound examinations. 1.4 Studies should be scheduled to avoid iodine-containing contrast media prior to thyroid imaging. 2 1.5 Carbimazole and Propylthiouracil are not contraindicated in patients undergoing 99Tcm pertechnetate thyroid scans and need not be discontinued prior to imaging.
    [Show full text]
  • Summary of Product Characteristics
    Health Products Regulatory Authority Summary of Product Characteristics 1 NAME OF THE MEDICINAL PRODUCT Ultra-TechneKow FM 2.15-43.00 GBq radionuclide generator 2 QUALITATIVE AND QUANTITATIVE COMPOSITION Sodium pertechnetate (99mTc) injection is produced by means of a (99Mo/99mTc) generator. Technetium (99mTc) decays with the emission of gamma radiation with a mean energy of 140 keV and a half-life of 6.01 hours to technetium (99Tc) which, in view of its long half-life of 2.13 x 105 years can be regarded as quasi stable. The radionuclide generator containing the parent isotope 99Mo, adsorbed on a chromatographic column delivers sodium pertechnetate (99mTc) injection in sterile solution. The 99Mo on the column is in equilibrium with the formed daughter isotope 99mTc. The generators are supplied with the following 99Mo activity amounts at activity reference time which deliver the following technetium (99mTc) amounts, assuming a 100% theoretical elution yield and 24 hours time from previous elution and taking into account that branching ratio of 99Mo is about 87%: 99mTc activity (maximum theoretical elutable 1.90 3.81 5.71 7.62 9.53 11.43 15.24 19.05 22.86 26.67 30.48 38.10 GBq activity at ART, 06.00 h CET) 99Mo activity (at ART, 06.00 h 2.15 4.30 6.45 8.60 10.75 12.90 17.20 21.50 25.80 30.10 34.40 43.00 GBq CET) The technetium (99mTc) amounts available by a single elution depend on the real yields of the kind of generator used itself declared by manufacturer and approved by National Competent Authority.
    [Show full text]
  • Technetium-99M Pertechnetate Uptake and Scanning in the Evaluation of Thyroid Function 4,(’).,..1.(J
    .—._.-——. ..—-—- ---,- -- -“ ~ .- ,-- c~ ..o~-~ ~ The Medical Research Center (5 :>NJL I&w 7 Brookhaven National J.aboratory IS-5 2!U Upton, L.L, New York =112 ) Technetium-99m Pertechnetate Uptake and Scanning in the Evaluation of Thyroid Function 4,(’).,..1.(j. .“yl~... By HAROLDL. ATXINS -J i Technetium-99m as pertechnetate is ac- radioiodine uptakes, the pertechnetate cumulated by the thyroid but not appre- uptake was sfightly superi&, with only t ciably organified. In this study, a method 5.9% errors in 488 patients. Radioiodine of detem]ining thyroidal uptake from the uptakes were in error in 7.8% of 270 scintiscan is described. The mean uptake individuals. In hyperthyroid patients, the in euthyroid individuals as measured by accuracy of the pertech-netate-uptake was this method was 1.73 * 0.85% with a 89.6% while the radioiodine uptake had normal range of 0.50-4.00$%0. Uptake an accuracy of 75.0%0. Both uptake was not affected by organic blocking determinations were highly inaccurate in agents. In a comparison of the overall hypothyroidism. - “ accuracy of pertechnetate and 24-hr HE UTILIZATION of 1811 for diagnostic thyroid studies has been routine Tfor more than two decades. Despite this, it is not a completely satisfactory agent for this purpose for a number of reasons. A relatively high radiation dose from the energetic beta emission is cause for concern in the light of the experience with the Marshallese exposed to fallout radiation, primarily radio- iodines.1 While no deleterious effects from diagnostic uses of iodine-131 have been demonstrated, they have not been specifically looked for.
    [Show full text]
  • Thyrotoxicosis Due to Atypical Subacute Thyroiditis Scintigraphicaly Presented As Toxic Adenoma – Case Report
    Case Report Annals of Clinical Case Reports Published: 17 Nov, 2016 Thyrotoxicosis due to Atypical Subacute Thyroiditis Scintigraphicaly Presented as Toxic Adenoma – Case Report Željka Aleksić1*, Aleksandar Aleksić2 and Nenad Ristović3 1Department of Nuclear Medicine, Health Center Zaječar, Serbia 2Department of Internal Medicine, Health Center Zaječar, Serbia 3Department of Infectious Disease, Health Center Zaječar, Serbia Abstract Subacute thyroiditis (SAT), also known as DeQuervain's or granulomatous thyroiditis is an inflammatory condition of the thyroid gland, which is usually fully affected. Severe pain and tenderness in the thyroid bed occur typically and are followed by weakness, fatigue, pain in muscles and joints, and light to moderate fever and symptoms of thyrotoxicosis - nervousness, sweating and rapid heart beat and trembling. Temporary elevated serum thyroxin, suppressed TSH and elevated serum markers of inflammation in the acute phase are pathognomonic for the SAT, with diffusely absent binding of radioactive iodine or technetium-pertechnetate in the thyroid gland due to thyrocytes destruction. Rare cases of atypical SAT - painless or with minimal pain, SAT limited to one thyroid lobe or focal thyroiditis, are reported in literature. We report a rare case of a minimally painful SAT associated with functional adenoma in the right lobe of the thyroid gland, which was, in thyrotoxic, acute phase, scintigraphicaly presented as toxic adenoma, in fact representing a functional adenoma tissue unaffected by destructive thyroiditis. Keywords: Atypical subacute thyroiditis; Autonomously functioning thyroid nodule; Toxic adenoma Introduction OPEN ACCESS Subacute thyroiditis (SAT), also known as DeQuervain's or granulomatous thyroiditis is an inflammatory condition of the thyroid gland, which is usually affected as a whole.
    [Show full text]
  • Alphabetical Listing of ATC Drugs & Codes
    Alphabetical Listing of ATC drugs & codes. Introduction This file is an alphabetical listing of ATC codes as supplied to us in November 1999. It is supplied free as a service to those who care about good medicine use by mSupply support. To get an overview of the ATC system, use the “ATC categories.pdf” document also alvailable from www.msupply.org.nz Thanks to the WHO collaborating centre for Drug Statistics & Methodology, Norway, for supplying the raw data. I have intentionally supplied these files as PDFs so that they are not quite so easily manipulated and redistributed. I am told there is no copyright on the files, but it still seems polite to ask before using other people’s work, so please contact <[email protected]> for permission before asking us for text files. mSupply support also distributes mSupply software for inventory control, which has an inbuilt system for reporting on medicine usage using the ATC system You can download a full working version from www.msupply.org.nz Craig Drown, mSupply Support <[email protected]> April 2000 A (2-benzhydryloxyethyl)diethyl-methylammonium iodide A03AB16 0.3 g O 2-(4-chlorphenoxy)-ethanol D01AE06 4-dimethylaminophenol V03AB27 Abciximab B01AC13 25 mg P Absorbable gelatin sponge B02BC01 Acadesine C01EB13 Acamprosate V03AA03 2 g O Acarbose A10BF01 0.3 g O Acebutolol C07AB04 0.4 g O,P Acebutolol and thiazides C07BB04 Aceclidine S01EB08 Aceclidine, combinations S01EB58 Aceclofenac M01AB16 0.2 g O Acefylline piperazine R03DA09 Acemetacin M01AB11 Acenocoumarol B01AA07 5 mg O Acepromazine N05AA04
    [Show full text]
  • The Outcome of a Calculated Radioiodine Dose Based On
    Malaysian Journal of Medicine and Health Sciences (eISSN 2636-9346) ORIGINAL ARTICLE The Outcome Of A Calculated Radioiodine Dose Based On Pertechnetate Thyroid Uptake Ratio In Treatment For Hyperthyroidism Lee Yeong Fong1,2, Ibrahim Lutfi Shuaib2, Fadzilah Hamzah1 1 Nuclear Medicine Department, Hospital Pulau Pinang, 10990 George Town, Pulau Pinang, Malaysia 2 Advanced Medical and Dental Institute, Universiti Sains Malaysia, Bertam, 13200 Kepala Batas, Pulau Pinang, Malaysia ABSTRACT Introduction: There are two dosing methods for radioiodine dose administration including empirical fixed dose and calculated dose. Recent meta-analysis supported that dose calculation is better than empirical fixed dose. However, dose calculation by dosimetry or 24 hours radioiodine uptake ratio can be tedious. Pertechnetate thyroid scintig- raphy is a simple nuclear imaging that can be completed on the same day and pertechnetate thyroid uptake ratio determined from the scintigraphy can be used to calculate the radioiodine dose. This research is done to measure the efficacy of the calculated dose regime. Methods: Hyperthyroidism patients referred for first radioiodine therapy were recruited. Pertechnetate thyroid scintigraphy was done and pertechnetate uptake ratio used for dose calculation. The outcome of the treatment was determined at six months. Results: A total of 95 patients were recruited. Six months after treatment, 82.1% of the calculated dose cohort achieved euthyroid or hypothyroid state. Participants with mul- tinodular goitre had higher failure rate than those with Graves’ disease (p=0.032) although there was no difference in the median RAI dose given (p=0.866). Conclusion: This calculated dose method showed good outcome with 82.1% cure rate at six months post treatment.
    [Show full text]
  • Uncommon Causes of Thyrotoxicosis*
    CONTINUING EDUCATION Uncommon Causes of Thyrotoxicosis* Erik S. Mittra1, Ryan D. Niederkohr1, Cesar Rodriguez1, Tarek El-Maghraby2,3, and I. Ross McDougall1 1Division of Nuclear Medicine and Molecular Imaging Program at Stanford, Department of Radiology, Stanford University Hospital and Clinics, Stanford, California; 2Nuclear Medicine, Cairo University, Cairo, Egypt; and 3Nuclear Medicine, Saad Specialist Hospital, Al Khobar, Saudi Arabia Several of the conditions are self-limiting and do not need Apart from the common causes of thyrotoxicosis, such as prolonged treatment. Graves’ disease and functioning nodular goiters, there are When a patient is thought to be thyrotoxic, a convenient more than 20 less common causes of elevated free thyroid hor- algorithm is to measure free thyroxine (free T ) and mones that produce the symptoms and signs of thyrotoxicosis. 4 thyrotropin (TSH). When the former is higher than normal This review describes these rarer conditions and includes 14 il- lustrative patients. Thyrotropin and free thyroxine should be but the latter is suppressed, thyrotoxicosis is diagnosed. measured and, when the latter is normal, the free triiodothyronine When the former is normal but TSH is low, it is valuable to 123 level should be obtained. Measurement of the uptake of Iis measure free triiodothyronine (free T3); when the latter is recommended for most patients. abnormally high, the diagnosis is T3 toxicosis (2–4). When Key Words: thyrotoxicosis; Graves’ disease; thyroiditis; thyroid both free hormones are normal but TSH is low, the term hormones ‘‘subclinical thyrotoxicosis’’ can be applied (5). Once it has J Nucl Med 2008; 49:265–278 been determined that thyrotoxicosis is present, measure- DOI: 10.2967/jnumed.107.041202 ment of 123I uptake can differentiate among several disor- ders (Table 1).
    [Show full text]
  • Technetium-99M Pertechnetate Imaging in Diagnosis of Meckel's Diverticulum JOHN C
    Arch Dis Child: first published as 10.1136/adc.49.1.21 on 1 January 1974. Downloaded from Archives of Disease in Childhood, 1974, 49, 21. Technetium-99m pertechnetate imaging in diagnosis of Meckel's diverticulum JOHN C. LEONIDAS and DONALD R. GERMANN From the Departments of Radiology, Children's Mercy and St. Luke's Hospitals; and the University of Missoutri School of Medicine, Kansas City, Missouri, U.S.A. Leonidas, J. C., and Germann, D. R. (1974). Archives of Disease in Childhood, 49, 21. Technetium-99m pertechnetate imaging in diagnosis of Meckel's diverticulum. Abdominal imaging after intravenous injection of 99mTc per- technetate is a simple, safe, and noninvasive diagnostic procedure to show ectopic gastric mucosa, which is present in most cases of symptomatic Meckel's diverticulum. It was performed in 13 infants and children suspected of having a Meckel's diverticulum, mainly because of unexplained rectal bleeding. Two of the three proven Meckel's diverticula were correctly identified by scintiscanning, while meticulous contrast x-ray studies were negative in each case. It is concluded that abdominal imaging is useful in the pre-operative diagnosis of symptomatic Meckel's diverticulum. Meckel's diverticulum is often asymptomatic; yet diverticula contain gastric mucosa, radionuclide it may cause alarming symptoms in the presence of imaging offers a quick, safe, and convenient method complications, such as haemorrhage, intus- for the pre-operative investigation of patients copyright. susception, or perforation (Gross, 1953). Bleeding suspected ofhaving a Meckel's diverticulum at a low from a Meckel's diverticulum is quite common in radiation exposure. infants; it is the result of peptic ulceration at the Since January 1972, radionuclide abdominal junction between ectopic gastric and normal ileal imaging has been performed in all infants and mucosa (Gross, 1953; Longino and Holder, 1959).
    [Show full text]