Investigation of a novel modified fixed dose determination protocol for radioiodine treatment of feline hyperthyroidism

dc.contributor.authorWentworth-Morre, Wendy Annen
dc.contributor.committeechairPanciera, David L.en
dc.contributor.committeememberMonroe, William E.en
dc.contributor.committeememberDaniel, Gregory B.en
dc.contributor.departmentVeterinary Medicineen
dc.date.accessioned2017-05-25T08:00:14Zen
dc.date.available2017-05-25T08:00:14Zen
dc.date.issued2017-05-24en
dc.description.abstractBackground: Radioiodine is the treatment of choice for feline hyperthyroidism. The ideal method of dose determination of 131I remains controversial. Objective: To compare a method of radioiodine dose determination that utilized thyroid scintigraphy with a standard fixed dose for treatment of feline hyperthyroidism. Methods: Fifty-seven and 23 cats were in the novel and fixed dose groups, respectively. Cats with a percent dose uptake as determined using 99mTcO4- uptake on thyroid scintigraphy <5%, 5-10%, and >10% were designated to receive 3 mCi, 3.5 mCi, or 4.5 mCi of 131I, respectively, administered subcutaneously. Radioiodine dose was adjusted by thyroid size, determined by evaluating the thyroid:salivary size ratio (T:S) and categorized as <5, 5-10, and >10. If the thyroid size fell into a higher dosing category than percent uptake, the dose was increased accordingly. Cats in the fixed dose group received 4.5 mCi of 131I. Six months after treatment, cats were determined to be euthyroid, hypothyroid, or hyperthyroid based on serum T4 concentrations relative to an established reference interval. Univariate analysis using Chi-square was used to determine associations between treatment and outcome. Results: There was no difference in outcome between the novel and fixed dose treatments. Euthyroidism, hypothyroidism, and hyperthyroidism developed in 61, 30, and 9% of cats in the fixed dose group, respectively compared to 58, 26, and 16% in the novel dose group. Conclusions: A modified fixed dose method of radioiodine based upon thyroid size and percent dose uptake was ineffective in improving outcomes over a standard fixed dose method.en
dc.description.degreeMaster of Scienceen
dc.format.mediumETDen
dc.identifier.othervt_gsexam:10998en
dc.identifier.urihttp://hdl.handle.net/10919/77856en
dc.publisherVirginia Techen
dc.rightsIn Copyrighten
dc.rights.urihttp://rightsstatements.org/vocab/InC/1.0/en
dc.subjecthyperthyroiden
dc.subjectradioiodineen
dc.subjectfelineen
dc.subjectscintigraphyen
dc.titleInvestigation of a novel modified fixed dose determination protocol for radioiodine treatment of feline hyperthyroidismen
dc.typeThesisen
thesis.degree.disciplineBiomedical and Veterinary Sciencesen
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen
thesis.degree.levelmastersen
thesis.degree.nameMaster of Scienceen

Files

Original bundle
Now showing 1 - 1 of 1
Loading...
Thumbnail Image
Name:
Wentworth-Morre_WA_T_2017.pdf
Size:
927.51 KB
Format:
Adobe Portable Document Format

Collections