H R Maxon

University of Cincinnati, Cincinnati, Ohio, United States

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Publications (78)450.55 Total impact

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    ABSTRACT: Thyroid cancer is unique for having age as a staging variable. Recently, the commonly used age cut-point of 45 years has been questioned. We assessed alternate staging systems on the outcome of overall survival, and compared these with current National Thyroid Cancer Treatment Cooperative Study (NTCTCS) staging systems for papillary and follicular thyroid cancer. We assessed 4,721 patients with differentiated thyroid cancer. Five potential alternate staging systems were generated at age cut-points in 5-year increments from 35 to 70 years, and tested for model discrimination (Harrell's C-statistic) and calibration (R2). The best five models for papillary and follicular cancer were further tested with bootstrap resampling and significance testing for discrimination. The best five alternate papillary cancer systems had age cut-points of 45-50 years, with the highest scoring model using 50 years. No significant difference in C-statistic was found between the best alternate and current NTCTCS systems (p=0.200). The best five alternate follicular cancer systems had age cut-points of 50-55 years, with the highest scoring model using 50 years. All five best alternate staging systems performed better compared with the current system (p=0.003 to 0.035). There was no significant difference in discrimination between the best alternate system (cut-point age 50 years) and the best system of cut-point age 45 years (p=0.197). No alternate papillary cancer systems assessed were significantly better than the current system. New alternate staging systems for follicular cancer appear to be better than the current NTCTCS system, although they require external validation.
    No preview · Article · Jul 2015 · Thyroid: official journal of the American Thyroid Association
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    ABSTRACT: Initial treatments for patients with differentiated thyroid cancer (DTC) are supported primarily by single-institution, retrospective studies, with limited follow-up and low event rates. We report updated analyses of long-term outcomes following treatment in patients with DTC. Examine effects of initial therapies on outcomes. Prospective multi-institutional registry. 4,941 patients; median follow-up 6 years. Total/near-total thyroidectomy (T/NTT), postoperative radioiodine (RAI), thyroid hormone suppression therapy (THST). Overall (OS), disease-free survival (DFS) using product limit and proportional hazards analyses. Improved OS was noted in NTCTCS stage III patients who received RAI (risk ratio [RR] 0.66, p=0.04) and stage IV patientswhoreceived both T/NTT and RAI (RR 0.66, 0.70, combined p=0.049). In all stages, moderate THST (TSH maintained subnormal-normal) was associated with significantly improved OS (RR stages I-IV: 0.13, 0.09, 0.13, 0.33) and DFS (RR stages I-III: 0.52, 0.40, 0.18); no additional survival benefit was achieved with more aggressive THST (TSH maintained undetectable- subnormal). This remained true, even when distant metastatic disease was diagnosed during follow-up. Lower initial stage and moderate THST were independent predictors of improved OS during follow-up years 1-3. We confirm previous findings that T/NTT followed by RAI is associated with benefit in high-risk but not low-risk patients. In contrast with earlier reports, moderate THST is associated with better outcomes across all stages, and aggressive THST may not be warranted even in patients.
    No preview · Article · Jul 2015 · The Journal of Clinical Endocrinology and Metabolism
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    ABSTRACT: Background: Serum thyrotropin (TSH) concentration and thyroid autoimmunity may be of prognostic importance in differentiated thyroid cancer (DTC). Preoperative serum TSH level has been associated with higher DTC stage in cross-sectional studies; data are contradictory on the significance of thyroid autoimmunity at the time of diagnosis. Objective: We sought to assess whether preoperative serum TSH and perioperative anti-thyroglobulin antibodies (TgAb) were associated with thyroid cancer stage and outcome in DTC patients followed by the National Thyroid Cancer Treatment Cooperative Study, a large multicenter thyroid cancer registry. Methods: Patients registered after 1996 with available preoperative serum TSH (n=617; the TSH cohort) or perioperative TgAb status (n=1770; the TgAb cohort) were analyzed for tumor stage, persistent disease, recurrence, and overall survival (OS) (median follow-up 5.5 years). Parametric tests assessed log transformed TSH, and categorical variables were tested with χ2. Disease-free survival (DFS) and OS was assessed with Cox models. Results: Geometric mean serum TSH levels were higher in patients with higher stage disease (stage III/IV=1.48 vs. 1.02 mU/L for stages I/II; P=0.006). The relationship persisted in those aged ≥45 years after adjusting for gender (P=0.01). Gross extrathyroidal extension (P=0.03) and presence of cervical lymph node metastases (P=0.003) were also significantly associated with higher serum TSH. Disease recurrence and all-cause mortality occurred in 37 and 38 TSH cohort patients respectively, which limited the power for survival analysis. Positive TgAb was associated with lower stage on univariate analysis (positive TgAb in 23.4% vs. 17.8% of stage I/II vs. III/IV patients, respectively; P=0.01), although the relationship lost significance when adjusting for age and gender (P=0.34). Perioperative TgAb was not an independent predictor of DFS (hazard ratio [HR]=1.12 [95%CI=0.74-1.69]) or OS (HR=0.98 [95%CI=0.56-1.72]). Conclusions: Preoperative serum TSH level is associated with higher DTC stage, gross extrathyroidal extension, and neck node metastases. Perioperative TgAb is not an independent predictor of DTC prognosis. A larger cohort is required to assess whether preoperative serum TSH level predicts recurrence or mortality.
    No preview · Article · Jun 2013 · Thyroid: official journal of the American Thyroid Association
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    ABSTRACT: Thyroid cancer predominately affects women, carries a worse prognosis in older age, and may have higher mortality in men. Superimposed on these observations is the fact that most women have attained menopause by age 55 yr. The objective of the study was to determine whether men contribute disproportionately to papillary thyroid cancer (PTC) mortality or whether menopause affects PTC prognosis. Gender-specific mortality was normalized using age-matched subjects from the U.S. population. Multivariate Cox proportional hazard regression models incorporating gender, age, and National Thyroid Cancer Treatment Cooperative Study Group stage were used to model disease-specific survival (DSS). Patients were followed in a prospective registry. The relationships between gender, age, and PTC outcomes were analyzed. The unadjusted hazard ratio (HR) for DSS for women was 0.40 [confidence interval (CI) 0.24-0.65]. This female advantage diminished when DSS was adjusted for age at diagnosis and stage with a HR encompassing unity (HR 0.72, CI 0.44-1.19). Additional multivariate models of DSS considering gender, disease stage, and various age groupings showed that the DSS for women diagnosed at under 55 yr was improved over men (HR 0.33, CI 0.13-0.81). However, the HR for DSS increased to become similar to men for women diagnosed at 55-69 yr (HR 1.01, CI 0.42-2.37) and at 70 yr or greater (HR 1.17, CI 0.48-2.85). Although the overall outcome of women with PTC is similar to men, subgroup analysis showed that this composite outcome is composed of two periods with different outcomes. The first period is a period with better outcomes for women than men when the diagnosis occurs at younger than 55 yr; the second is a period with similar outcomes for both women and men diagnosed at ages greater than 55 yr. These data raise the question of whether an older age cutoff would improve current staging systems. We hypothesize that older age modifies the effect of gender on outcomes due to menopause-associated hormonal alterations.
    No preview · Article · Apr 2012 · The Journal of Clinical Endocrinology and Metabolism
  • Kyuran A. Choe · Harry R. Maxon
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    ABSTRACT: In an extensive review of this subject, 1095/3083 (35.5%) patients with papillary carcinoma and 102/797 (12.8%) patients with follicular carcinoma were found to have lymph node metastases at the time of initial diagnosis of their cancer (1). In children, the prevalence may be as high as 70% (2). Of patients thought to be disease free after their initial treatment, 252/2684 (9.4%) with papillary and 43/641 (6.7%) with follicular carcinoma subsequently developed nodal metastases (1).
    No preview · Chapter · Jul 2011
  • James Brierley · Harry R. Maxon
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    ABSTRACT: For over 50 years, radioiodine-131 has been used in the post surgical treatment of differentiated thyroid cancer (1). In 1957, workers at the University of Michigan popularized 131I in an easy to use, empiric approach that recommended the administration of fixed activities of 131I to patients who were allowed to become hypothyroid after their initial surgical therapy (2). It soon became evident that only about 70-80% of differentiated thyroid cancers would concentrate 131I under these conditions (3). When patients whose recurrent/metastatic cancers could not be shown to concentrate 131I on diagnostic 131I scans were excluded, then 131I therapy given to the point of “ablation” of 131I uptake on subsequent diagnostic scans resulted in a significant improvement in mortality (4). The methods of patient preparation and treatment that were developed during the first 25 years of 131I use have not been modified in most health care facilities. In part this has been due to a shift in physician training. During the first 25 years, about 80% of nuclear medicine physicians entered the field from backgrounds in internal medicine, resulting in interest and training both in diseases of the thyroid and in the use of radioactive medicine by radiologists who are interested primarily in image interpretation or by endocrinologists who are not broadly trained in the intricacies of the use of radioactive materials, both of which groups find the decades old empiric approaches convenient to use.
    No preview · Chapter · Feb 2011

  • No preview · Article · Nov 2010 · Thyroid: official journal of the American Thyroid Association
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    ABSTRACT: Despite very low mortality associated with micropapillary thyroid cancer, locoregional recurrence is common and controversy exists regarding optimal surgical treatment and the role of adjunctive radioiodine. The National Thyroid Cancer Treatment Cooperative Study Group Registry was analyzed for recurrences in patients with unifocal versus multifocal micropapillary cancer, with or without nodal disease, depending upon the extent of surgery and the use of adjunctive radioiodine. Six hundred eleven patients considered disease-free after initial therapy were followed for 2572 person-years. Thirty patients (6.2%) had recurrences detected at a mean 2.8 years after primary treatment. Recurrences did not differ between patients with unifocal and multifocal disease overall; however, among patients who received less than a near-total thyroidectomy (NTT), those with multifocal disease had more recurrences than those with unifocal disease (18% vs. 4%, p = 0.01). Patients with multifocal disease who had a total (T) or NTT trended toward fewer recurrences than those undergoing less than an NTT (6% vs. 18%, p = 0.058). In patients who did not receive radioiodine therapy, recurrence was more common in patients with multifocal disease versus unifocal disease (7% vs. 2%, p = 0.02). However, radioiodine did not reduce recurrences in patients with multifocal disease or patients with positive nodes. Patients with positive nodes had more recurrences than node-negative patients regardless of surgical extent or use of radioiodine. Patients with micropapillary multifocal disease have a reduced risk of recurrence after a T/NTT compared with less surgery. A randomized, controlled trial is necessary and feasible to determine if radioiodine ablation of thyroid remnants is advantageous in patients with intrathyroidal micropapillary cancer.
    No preview · Article · Sep 2009 · Thyroid: official journal of the American Thyroid Association
  • Source
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    ABSTRACT: This analysis was performed to determine the effect of initial therapy on the outcomes of thyroid cancer patients. The study setting was a prospectively followed multi-institutional registry. Patients were stratified as low risk (stages I and II) or high risk (stages III and IV). Treatments employed included near-total thyroidectomy, administration of radioactive iodine, and thyroid hormone suppression therapy. Outcome measures were overall survival, disease-specific survival, and disease-free survival. Near-total thyroidectomy, radioactive iodine, and aggressive thyroid hormone suppression therapy were each independently associated with longer overall survival in high-risk patients. Near-total thyroidectomy followed by radioactive iodine therapy, and moderate thyroid hormone suppression therapy, both predicted improved overall survival in stage II patients. No treatment modality, including lack of radioactive iodine, was associated with altered survival in stage I patients. Based on our overall survival data, we confirm that near-total thyroidectomy is indicated in high-risk patients. We also conclude that radioactive iodine therapy is beneficial for stage II, III, and IV patients. Importantly, we show for the first time that superior outcomes are associated with aggressive thyroid hormone suppression therapy in high-risk patients, but are achieved with modest suppression in stage II patients. We were unable to show any impact, positive or negative, of specific therapies in stage I patients.
    Full-text · Article · Jan 2007 · Thyroid
  • Harry R. Maxon
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    ABSTRACT: Radioiodine-131 imaging is the traditional method of detecting residual or recurrent differentiated thyroid cancer. The stimulation of such tissues to take up radioiodine may be achieved either by complete cessation of thyroid hormone, by partial thyroid hormone withdrawal, or by the administration of recombinant human thyrotropin (TSH). Complete or partial thyroid hormone withdrawal may result in serum TSH concentrations adequate for radioiodine imaging in up to 90% of patients. When known or suspected recurrent or metastatic disease is not evident on radioiodine imaging, single photon emission tomographic imaging with either thallium-201 chloride or technetium-99m-MIBI compounds may detect up to 80%-90% of cancers at least 1 to 1.5 cm in size, although specificity is less than with 131I. Fluorine-18-FDG positron emission tomography is a somewhat less available but acceptable substitute for thallium-201 or 99mTc-MIBI imaging. Tumor foci that concentrate either TI-201 or 18FDG intensely with little or no 131I uptake appear to behave more aggressively than those concentrating 131I avidly.
    No preview · Article · Jun 1999 · Thyroid
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    ABSTRACT: Treatment of differentiated thyroid cancer has been studied for many years, but the benefits of extensive initial thyroid surgery and the addition of radioiodine therapy or external radiation therapy remain controversial. To determine the relations among extent of surgery, radioiodine therapy, and external radiation therapy in the treatment of high-risk papillary and non-Hürthle-cell follicular thyroid carcinoma. Analysis of data from a multicenter study. 14 institutions in the United States and Canada participating in the National Thyroid Cancer Treatment Cooperative Study Registry. 385 patients with high-risk thyroid cancer (303 with papillary carcinoma and 82 with follicular carcinoma). Death, disease progression, and disease-free survival. Total or near-total thyroidectomy was done in 85.3% of patients with papillary carcinoma and 71.3% of patients with follicular cancer. Overall surgical complication rate was 14.3%. Total or near-total thyroidectomy improved overall survival (risk ratio [RR], 0.37 [95% CI, 0.18 to 0.75]) but not cancer-specific mortality, progression, or disease-free survival in patients with papillary cancer. No effect of extent of surgery was seen in patients with follicular thyroid cancer. Postoperative iodine-131 was given to 85.4% of patients with papillary cancer and 79.3% of patients with follicular cancer. In patients with papillary cancer, radioiodine therapy was associated with improvement in cancer-specific mortality (RR, 0.30 [CI, 0.09 to 0.93 by multivariate analysis only]) and progression (RR, 0.30 [CI, 0.13 to 0.72]). When tall-cell variants were excluded, the effect on outcome was not significant. After radioiodine therapy, patients with follicular thyroid cancer had improvement in overall mortality (RR, 0.17 [CI, 0.06 to 0.47]), cancer-specific mortality (RR, 0.12 [CI, 0.04 to 0.42]), progression (RR, 0.21 [CI, 0.08 to 0.56]), and disease-free survival (RR, 0.29 [CI, 0.08 to 1.01]). External radiation therapy to the neck was given to 18.5% of patients and was not associated with improved survival, lack of progression, or disease-free survival. This study supports improvement in overall and cancer-specific mortality among patients with papillary and follicular thyroid cancer after postoperative iodine-131 therapy. Radioiodine therapy was also associated with improvement in progression in patients with papillary cancer and improvement in progression and disease-free survival in patients with follicular carcinoma.
    Full-text · Article · Nov 1998 · Annals of internal medicine
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    ABSTRACT: The ideal therapy for differentiated thyroid cancer is uncertain. Although thyroid hormone treatment is pivotal, the degree of thyrotropin (TSH) suppression that is required to prevent recurrences has not been studied in detail. We have examined the relation of TSH suppression to baseline disease characteristics and to the likelihood of disease progression in a cohort of thyroid cancer patients who have been followed in a multicenter thyroid cancer registry that was established in 1986. The present study describes 617 patients with papillary and 66 patients with follicular thyroid cancer followed annually for a median of 4.5 years (range 1-8.6 years). Cancer staging was assessed using a staging scheme developed and validated by the registry. Cancer status was defined as no residual disease; progressive disease at any follow-up time; or death from thyroid cancer. A mean TSH score was calculated for each patient by averaging all available TSH determinations, where 1 = undetectable TSH; 2 = subnormal TSH; 3 = normal TSH; and 4 = elevated TSH. Patients were also grouped by their TSH scores: group 1: mean TSH score 1.0-1.99; group 2: mean TSH score 2.0-2.99; group 3: mean TSH score 3.0-4.0. The degree of TSH suppression did not differ between papillary and follicular thyroid cancer patients. However, TSH suppression was greater in papillary cancer patients who were initially classified as being at higher risk for recurrence. This was not the case for follicular cancer patients, where TSH suppression was similar for all patients. For all stages of papillary cancer, a Cox proportional hazards model showed that disease stage, patient age, and radioiodine therapy all predicted disease progression, but TSH score category did not. However, TSH score category was an independent predictor of disease progression in high risk patients (p = 0.03), but was no longer significant when radioiodine therapy was included in the model (p = 0.09). There were too few patients with follicular cancer for multivariate analysis. These data suggest that physicians use greater degrees of TSH suppression in higher risk papillary cancer patients. Our data do not support the concept that greater degrees of TSH suppression are required to prevent disease progression in low-risk patients, but this possibility remains in high-risk patients. Additional studies with more patients and longer follow-up may provide the answer to this important question.
    No preview · Article · Oct 1998 · Thyroid
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    ABSTRACT: A novel prognostic staging classification encompassing all forms of thyroid carcinoma was created for the National Thyroid Cancer Treatment Cooperative Study (NTCTCS) Registry, with the goal of prospective validation and comparison with other available staging classifications. Patient information was recorded prospectively from 14 institutions. Clinicopathologic staging was based on patient age at diagnosis, tumor histology, tumor size, intrathyroidal multifocality, extraglandular invasion, metastases, and tumor differentiation. Between 1987 and 1995, 1607 patients were registered. Approximately 43% of patients were classified as NTCTCS Stage I, 24% Stage II, 24% Stage III, and 9% Stage IV. Patients with follicular carcinoma were more likely to have "high risk" Stage III or IV disease than those with papillary carcinoma. Of 1562 patients for whom censored follow-up was available (median follow-up, 40 months), 78 died of thyroid carcinoma or complications of its treatment. Five-year product-limit patient disease specific survival was 99.8% for Stage I, 100% for Stage II, 91.9% for Stage III, and 48.9% for Stage IV (P < 0.0001). The frequency of remaining disease free also declined significantly with increasing stage (94.3% for Stage I, 93.1%for Stage II, 77.8% for Stage III, and 24.6% for Stage IV). The same patients also were staged applying six previously published classifications as appropriate for their tumor type. The predictive value of the NTCTCS Registry staging classification consistently was among the highest for disease specific mortality and for remaining disease free, regardless of the tumor type. The NTCTCS Registry staging classification provides a prospectively validated scheme for predicting short term prognosis for patients with thyroid carcinoma.
    No preview · Article · Sep 1998 · Cancer
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    ABSTRACT: A novel prognostic staging classification encompassing all forms of thyroid carcinoma was created for the National Thyroid Cancer Treatment Cooperative Study (NTCTCS) Registry, with the goal of prospective validation and comparison with other available staging classifications. Patient information was recorded prospectively from 14 institutions. Clinicopathologic staging was based on patient age at diagnosis, tumor histology, tumor size, intrathyroidal multifocality, extraglandular invasion, metastases, and tumor differentiation. Between 1987 and 1995, 1607 patients were registered. Approximately 43% of patients were classified as NTCTCS Stage I, 24% Stage II, 24% Stage III, and 9% Stage IV. Patients with follicular carcinoma were more likely to have "high risk" Stage III or IV disease than those with papillary carcinoma. Of 1562 patients for whom censored follow-up was available (median follow-up, 40 months), 78 died of thyroid carcinoma or complications of its treatment. Five-year product-limit patient disease specific survival was 99.8% for Stage I, 100% for Stage II, 91.9% for Stage III, and 48.9% for Stage IV (P < 0.0001). The frequency of remaining disease free also declined significantly with increasing stage (94.3% for Stage I, 93.1% for Stage II, 77.8% for Stage III, and 24.6% for Stage IV). The same patients also were staged applying six previously published classifications as appropriate for their tumor type. The predictive value of the NTCTCS Registry staging classification consistently was among the highest for disease specific mortality and for remaining disease free, regardless of the tumor type. The NTCTCS Registry staging classification provides a prospectively validated scheme for predicting short term prognosis for patients with thyroid carcinoma. [See editorial counterpoint on pages 844-7 and reply to counterpoint on pages 848-50, this issue.] Cancer 1998;83:1012-1021.
    No preview · Article · Sep 1998 · Cancer
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    ABSTRACT: Rhenium-188 (tin) hydroxyethylidine diphosphonate [188Re(Sn)HEDP] is a new radiopharmaceutical that localizes in skeletal metastases and emits beta particles that may be therapeutically beneficial. It was evaluated by in vitro and in vivo testing in the laboratory, in animals and in humans using 188Re from a variety of sources. It may be produced by a desk-top method developed previously for 186Re(Sn)HEDP using 188Re produced through neutron irradiation of either enriched 187Re or naturally occurring rhenium targets or the use of a 188W/188Re generator. So long as the mass of rhenium in the 188Re-perrhenate to be processed into 188Re(Sn)HEDP is at least 100 microg, satisfactory radiochemical yields and purity may be obtained by all methods. The 188Re(Sn)HEDP has biodistribution and radiation dosimetry characteristics that are similar to those noted previously for 186Re(Sn)HEDP and appears to result in similar benefits and toxicities in patients with skeletal metastases. External radiation exposure monitoring indicates that, only 4 hr after a therapeutic administration of 1110 MBq (30 mCi) of 188Re(Sn)HEDP, average exposure rates at 1 meter from the patient would be only 0.5 mR/hr. Same-day, on-demand, outpatient therapy of disseminated skeletal metastases appears to be feasible with 188Re(Sn)HEDP.
    Full-text · Article · Apr 1998 · Journal of Nuclear Medicine
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    ABSTRACT: When macrometastases are delineated clearly using current radiographic techniques and/or physical examination and can be shown to concentrate 131I, the therapeutic activity to be administered may be determined quantitatively. Administrations of 131I that will deliver 30,000 rad to residual thyroid tissue or 10,000 +/- 2,000 rad to lymph node metastases will ablate them successfully 80% of the time, and bone marrow depression that is severe enough to require specialized treatment will be avoided if the whole blood dose from a single administration does not exceed 200 rad. When micrometastases are detected only by diagnostic radioiodine imaging and/or elevations of serum thyroglobulin levels, and when a clinical decision is made to treat them with radioiodine, then 131I may not be the isotope choice. With small lesions < 0.05 mm in diameter, the lower energy emissions of 125I therapy may be more suitable. With the advent of alternative methods of patient preparation for radioiodine therapy, empiric approaches that were derived from experience with endogenously hypothyroid patients will require full re-evaluation. Approaches based on quantitative radiodosimetric calculations will continue to be valid because they already consider individual differences in radioiodine kinetics.
    No preview · Article · Apr 1997 · Thyroid
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    ABSTRACT: Early diagnosis of osteomyelitis continues to be a clinical problem. Multiple imaging modalities are being used for the diagnosis of osteomyelitis, but none of them is ideal for all cases. The choice of modality depends on several factors based on an understanding of the pathophysiologic aspects of different forms of osteomyelitis. After a brief introduction outlining some basic principles regarding the diagnosis of osteomyelitis, pathophysiologic aspects are reviewed. Advantages and disadvantages of each imaging modality and their applications in different forms of osteomyelitis are discussed. The use of different imaging modalities in the diagnosis of special forms of osteomyelitis, including chronic, diabetic foot, and vertebral osteomyelitis, and osteomyelitis associated with orthopedic appliances and sickle cell disease is reviewed. Taking into account the site of suspected osteomyelitis and the presence or absence of underlying pathologic changes and their nature, an algorithm summarizing the use of various imaging modalities in the diagnosis of osteomyelitis is presented.
    No preview · Article · Oct 1995 · European Journal of Nuclear Medicine
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    ABSTRACT: Trans (N,N'-ethylene bis(acetylacetoneimine)) bis(tris(3-methoxy-1-propyl) phosphine) 99mTc(III) (99mTc-Q3) has been developed for myocardial perfusion imaging. Biokinetic studies and dosimetry analysis have been completed for six healthy volunteers. The same-day two-injection protocol involved (1) an average rest injection of 241 MBq of 99mTc-Q3 followed by myocardial single-photon emission computed tomography (SPECT) at 15.0 minutes and a whole body (WB) scan at 1.5 hours; and (2) an average stress injection during treadmill exercise of 744 MBq of 99mTc-Q3 at 2.4 hours (postrest injection) followed by myocardial SPECT and additional WB scans at 1.5, 3.5, 6.5, and 21 hours poststress injection. Total urine was collected over 24 hours. Absolute organ activities were determined by conjugate counting methods. The two-injection data were simplified to a one-injection equivalent data set to facilitate dosimetry analysis. Decay corrected average percentage uptake values, plus or minus one standard deviation, for the myocardium were 1.4% +/- 0.2% at approximately 1.5 hours for both the postrest and poststress injections. The average biologic half-time for the myocardium was 26.4 hours. The highest organ uptake values included the gallbladder with 5.5% +/- 1.9% and the liver with 4.1% +/- 1.0% at the 1.5 hours poststress scan time. The sum of all gastrointestinal (GI) tract components was 18.8% +/- 9.4% at approximately 6.5 hours poststress injection (before any fecal elimination). The total 24 hour urine clearance was 17.1% +/- 2.4%. The gallbladder wall and upper large intestine wall received the highest doses at 0.024 and 0.023 mGy/MBq, respectively. The effective dose equivalent is estimated to be 0.01 mSv/MBq, which for an administration of 1110 MBq (30 mCi) is less than half that of a standard imaging protocol using 111 MBq (3 mCi) of 201Tl, and comparable to the published estimates for 99mTc-labeled sestamibi and 99mTc-labeled tetrofosmin (also normalized to 1110 MBq of administered activity). The 99mTc-Q3 exhibits myocardium uptake similar to that for these other two 99mTc agents.
    No preview · Article · Sep 1995 · Journal of Nuclear Cardiology
  • L.C. Washburn · D.S. Biniakiewicz · H.R. Maxon
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    ABSTRACT: 99mTc pentavalent dimercaptosuccinic acid [99mTc (V) DMSA], a useful agent for imaging thyroid medullary carcinoma and other tumors, can be reliably prepared by addition of NaHCO3 and then Na99mTcO4 to a commercial kit for 99mTc trivalent DMSA [99mTc (III) DMSA], followed by bubbling oxygen through the solution for 10 min. 99mTc (V) DMSA made by this method is radiochemically pure and stable for 24 h, and it gives a rat biodistribution similar to that of the agent made by previous methods. Clinical biodistribution and radiation dosimetry studies are planned.
    No preview · Article · Aug 1995 · Nuclear Medicine and Biology
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    ABSTRACT: Thirty-one adult patients with clinical findings suggestive of pheochromocytoma were studied with I-123 MIBG. All patients had images obtained at 24 and 48 hours. Five patients had abnormal uptake proved to be because of I-123 MIBG avid tumors. The remaining 26 patients had no proven tumors and showed physiologic uptake in various organs. The 24-hour images were of high quality. In all cases, the 48-hour images contributed no significant additional information. Only in 1 patient did the 48-hour image add some certainty. Physiologic uptake was seen in the salivary glands, liver, G.I. tract, and urinary bladder in all patients (100%). Uptake was also observed in the lung and heart (90%), normal adrenal glands (32%), thyroid (29%), spleen (23%) uterus (13%), and neck muscles (6%). The authors' experience indicates that I-123 MIBG gives superior images compared to the previously used I-131 MIBG, that the optimum imaging time for adults is 18-24 hours, and that normal distribution patterns including uterine and neck muscle uptake should be familiar to physicians interpreting the studies.
    No preview · Article · Mar 1995 · Clinical Nuclear Medicine

Publication Stats

3k Citations
450.55 Total Impact Points

Institutions

  • 1978-2015
    • University of Cincinnati
      • • Department of Radiology
      • • Department of Environmental Health
      • • Department of Chemistry
      Cincinnati, Ohio, United States
    • Barnes Jewish Hospital
      San Luis, Missouri, United States
  • 2007
    • Johns Hopkins University
      Baltimore, Maryland, United States
  • 1978-1999
    • University of Cincinnati Medical Center
      Cincinnati, Ohio, United States
  • 1998
    • University of Missouri
      Columbia, Missouri, United States
    • University of Texas MD Anderson Cancer Center
      • Endocrine Neoplasia and Hormonal Disorders
      Houston, TX, United States
    • Cornell University
      Итак, New York, United States
  • 1995
    • Boston Children's Hospital
      Boston, Massachusetts, United States
  • 1976-1981
    • Cincinnati Eye Hospital
      Cincinnati, Ohio, United States