Objectives: I-131 is a widely used radiopharmaceutical for the management of patients with differentiated thyroid carcinoma (DTC). It is the main agent for the ablation of residual thyroid tissue and the treatment of recurrent or metastatic DTC. However, diagnostic doses of I-131 larger than 3 mCi will cause some form of cell damage "stunning" which reduce subsequent uptake of the therapeutic dose of I-131. In contrast, I-123 is considered an ideal isotope for diagnostic studies, it emits only gamma radiation and thus lacks the stunning effect. The aim of the current study was to assess the impact of post-thyroidectomy I-123 versus I-131 Whole Body Scan (WBS) on the outcome of I-131 ablation for DTC. Methods: 70 consecutive DTC patients (60 papillary thyroid Ca., and 10 Follicular thyroid Ca.), underwent total thyroidectomy, followed by WBS, neck ultrasound (US), and subsequent I-131 ablation after 40 days without thyroid hormone replacement (TSH > 30 µIU/ml) were retrospectively enrolled in current study. Scans were acquired using the Forte dual head gamma camera (Phillips medical systems) equipped with a low energy parallel hole collimator, 24 hours after an oral administration of 37-111 MBq (1-3 mCi) of I-123, in 41 patients (Group 1), and equipped with a high energy parallel hole collimator, 48 hours after an oral administration of 74-185 MBq (2-5mCi) of I-131 in 29 patients (Group 2). 6 months later follow up I-131 WBS, neck US, serum thyroglobulin (Tg) and Tg antibodies (TgAb) were performed following suspension of L-thyroxin for one month (TSH > 30 µIU/ml) in 61 patients and following rhTSH stimulation in 9 patients. Results: No significant difference regarding age, gender and histopathology between both groups. 32/41, (78%) patients of group (1) and 16/29 (55%) of group (2) had negative follow up WBS, however, 5 patients of group (1), and 4 of group (2) with negative follow up WBS, had Tg > 5 ng/ml, with US findings suggestive of residual disease in the neck. The overall successful ablation rate were 27/41, 66% in group (1) versus 12/29, 41.4% in group (2) (P = 0.042). Conclusions: We found a significantly higher successful I-131 ablation rate among patients studied with I-123 WBS compared to those studied with I-131 WBS before radioiodine ablation, and recommend the use of I-123 instead of I-131 for WBS before radioiodine ablation.

BACKGROUND: Abnormality of left ventricular (LV) diastolic function is frequently the earliest indicator of LV dysfunction in many diseases, including coronary artery disease (CAD), and hypertension. Electrocardiography (ECG)-gated technetium (Tc) -99m tetrofosmin single-photon emission computed tomography (SPECT) has been reported to be a useful method for evaluation of LV function. OBJECTIVES: The purpose of this study is to assess the impact of hypertension on diastolic left ventricular function using ECG-gated Tc-99m tetrofosmin SPECT METHODS: Thirty consecutive patients with normal exercise myocardial perfusion and normal LV systolic function, were studied out of 233 patients underwent ECG-gated Tc-99m tetrofosmin SPECT at our institution between Jan 2012 and Dec 2013. Patients were divided into two groups according to the presence or absence of systemic hypertension (blood pressure > or = 140/90 mm Hg on > or = 3 measurements or treatment with antihypertensive medication). Parameters of diastolic LV function were assessed. Results: Of the studied 30 patients, 19/30 (63%) had hypertension. There was no difference with respect to age, gender, LV end-diastolic volume (EDV), LV end-systolic volume (ESV), and LV ejection fraction values obtained by quantitative gated SPECT between patients with and without hypertension. The first-third mean filling rate (1/3 MFR), peak filling rate (PFR) of patients with hypertension (1.22 ± 0.38, 2.83 ± 1.10 EDV/s) were significantly lower than those of patients without hypertension (1.54 ± 0.30, 2.90 ± 0.35 EDV/s) (P 0.05), and the time to peak filling (TTPF) of patients with hypertension (199.42 ± 68.34 ms) was higher than TTPF of patients without hypertension (164.90 ± 36.39 ms). CONCLUSIONS: Quantitative ECG-gated Tc-99m tetrofosmin SPECT reveals that hypertensive patients with preserved global LV systolic function may have significant changes in diastolic LV function. Gated myocardial perfusion SPECT reports are always lacking in these changes in diastolic function. We recommend inclusion of such changes in diastolic function in gated myocardial perfusion SPECT reports that can help in proper management of hypertensive patients.

Objectives Internal carotid artery sacrifice (ICAS) may be required in treatment of cerebral aneurysms and tumors and is a high risk procedure. The interventional radiology balloon temporary occlusion test (IRBTO) paired with the two day Tc99m-bicisate brain perfusion study (BPS) can be a useful way to predict the outcome before occluding the artery in question. The purpose of this study is to examine the value of BPS exams as a predictor of stroke risk prior to ICAS. Methods 14 cases eligible for ICAS were retrospectively reviewed. IRBTO was positive if the patient developed neurological deficit during temporary IRBTO. The BPS exam was positive if the patient showed an area of focal hypoperfusion on the occlusion phase, but not on the baseline study done 24 h apart. The exam was negative if there was no perfusion abnormality on either phase. The results of the BPS were compared to occurrences of post-occlusion infarct. Results ICAS was indicated in 14 cases [mean age 59.2± 25.2, M: F=2:12, aneurysm:tumor = 10:4]. One case with positive IRBTO: therefore did not proceed to BPS or ICAS. The remaining 13/14 (93%) cases had IRBTO, BPS, and subsequent ICAS. Of the 93%, 8% had a positive IRBTO and 15% had a positive BPS. Following ICAS (n=13), 4 cases developed infarct. Of those 4, 3 cases were negative on both exams (IRBTO and BPS). One case was positive on BPS and did not develop infarct. One case which was positive on both exams developed infarct after having ICAS at an outside facility. Conclusions Combined IRBTO and BPS is an effective way in predicting focal neurological deficit prior to ICAS. Considering the risk of ICAS, the best patient outcomes are obtainable when both IRBTO and BPS are performed and negative.

Objectives Recently, it is frequently proposed that diagnostic 131-Iodine Whole-Body Scan (DWBS) may be avoided in patients with undetectable levels of serum thyroglobulin (Tg) off L-thyroxine, and that Tg levels are sufficient as the sole surveillance test in low risk Differentiated Thyroid Carcinoma patients (DTC), particularly if the first post 131-Iodine treatment follow up DWBS, Tg and Tg antibodies (Tg Ab) are negative. The aim of the current study was to evaluate the role of DWBS in follow up of DTC. Methods Follow up DWBS and serum Tg levels of 52 consecutive patients (44 papillary thyroid carcinoma, and 8 Follicular thyroid carcinoma including one Hürthle cell variant) were reterospectively evaluated. Scans were acquired using a high energy collimator fitted to Phillips Forte dual head gamma camera, 48 hours after an oral administration of 2.5 - 3.9 mCi I-131 capsule. An Immunoluminescent assay (Bioscientia, Ingelheim, Germany) was used for serum Tg determination. DWBS and Tg assay were performed following suspension of L-thyroxine for one month (TSH > 30 µIU/ml) in 45 patients and following rhTSH stimulation in 7 patients. Results Of the 52 studied patients, 4 were excluded because of high serum Tg Ab. Of the remaining 48 patients, 11/48 (22.9%) had positive DWBS but negative Tg, 6/48 (12.5%) had negative DWBS but positive Tg, and 31/48 (64.6%) had concordant DWBS and Tg results. Conclusions In follow up of DTC, the results of DWBS and Tg were discordant in more than one third of patients. Our findings suggest that in follow up of DTC, DWBS still provides useful information, and both DWBS and serum Tg should be evaluated

Objectives: The rate and impact of thyroglossal duct remnant (TGDR) visualization in patients with hypothyroidism after total thyroidectomy for differentiated thyroid carcinoma (DTC) have not yet been fully determined. The aim of this study was to assess the rate of TGDR visualization in post total thyroidectomy whole body scan (WBS) for DTC and to evaluate its impact on the outcome of I-131 ablation. Methods: A total of 60 consecutive DTC patients (51 papillary thyroid Ca., and 9 Follicular thyroid Ca.), underwent total thyroidectomy, followed by WBS (using I-131 in 28 patients and I-123 in 32 patients), neck ultrasound (US), thyroglobulin (Tg) and Tg anti-bodies (TgAb) assay after 40 days and subsequent I-131 ablation. At 6 months later follow-up I-131 WBS, neck U/S, Tg and TgAb were performed following suspension of L-thyroxine for 1-month (thyroid stimulating hormone [TSH] >30 μIU/ml) in 53 patients and following recombinant human TSH stimulation in seven patients. Results: Of the studied 60 patients, 19/60 (31.7%) had a linear or focal radioactivity at the superior midline of the neck, suggesting TGDR (Group 1), and 41/60 (68.3%) had no uptake to suggest TGDR (Group 2). No significant difference regarding age, gender and histopathology between both groups. Neck US showed no evidence of thyroid tissue in the superior midline of the neck in both groups, and only a small or no residual thyroid tissue in patients of Group 1. There was a significant successful I-131 ablation rate among patients of group 1 compared to group 2 (79% in Group 1 vs. 41.5% in Group 2) (P = 0.007). Conclusions: Thyroglossal duct remnant visualization on WBS of hypothyroid subjects after total thyroidectomy suggests presence of only a small or no residual functioning thyroid tissue at the thyroid bed and can predict a good response to I-131 ablation.

Objectives: The rate and impact of thyroglossal duct remnant (TGDR) visualization in patients with hypothyroidism after total thyroidectomy for differentiated thyroid carcinoma (DTC) have not yet been fully determined. The aim of this study was to assess the rate of TGDR visualization in post total thyroidectomy whole body scan (WBS) for DTC and to evaluate its impact on the outcome of I-131 ablation. Methods: A total of 60 consecutive DTC patients (51 papillary thyroid Ca., and 9 Follicular thyroid Ca.), underwent total thyroidectomy, followed by WBS (using I-131 in 28 patients and I-123 in 32 patients), neck ultrasound (US), thyroglobulin (Tg) and Tg anti-bodies (TgAb) assay after 40 days and subsequent I-131 ablation. At 6 months later follow-up I-131 WBS, neck U/S, Tg and TgAb were performed following suspension of L-thyroxine for 1-month (thyroid stimulating hormone [TSH] >30 μIU/ml) in 53 patients and following recombinant human TSH stimulation in seven patients. Results: Of the studied 60 patients, 19/60 (31.7%) had a linear or focal radioactivity at the superior midline of the neck, suggesting TGDR (Group 1), and 41/60 (68.3%) had no uptake to suggest TGDR (Group 2). No significant difference regarding age, gender and histopathology between both groups. Neck US showed no evidence of thyroid tissue in the superior midline of the neck in both groups, and only a small or no residual thyroid tissue in patients of Group 1. There was a significant successful I-131 ablation rate among patients of group 1 compared to group 2 (79% in Group 1 vs. 41.5% in Group 2) (P = 0.007). Conclusions: Thyroglossal duct remnant visualization on WBS of hypothyroid subjects after total thyroidectomy suggests presence of only a small or no residual functioning thyroid tissue at the thyroid bed and can predict a good response to I-131 ablation.

Objectives: Renal cortical scintigraphy with technetium-99m (Tc-99m) dimercaptosuccinic acid (DMSA) is the method of choice to detect acute pyelonephritis and cortical scarring. Different acquisition methods have been used: Planar parallel-hole or pinhole collimation and single photon emission tomography (SPECT). This study compared planar parallel-hole cortical scintigraphy and dual-head SPECT for detection of cortical defects. Patients and Methods: We retrospectively reviewed 190 consecutive patients with 380 kidneys and 200 DMSA scans referred to rule out renal cortical scarring. The diagnoses were 52 vesicoureteric reflux, 61 recurrent urinary tract infection, 39 hydronephrosis, 20 renal impairment, and 18 hypertension. All patients were imaged 3 h after injection of Tc-99m DMSA with SPECT and planar imaging (posterior, anterior, left, and right posterior oblique views). For each patient, planar and SPECT images were evaluated at different sittings, in random order. Each kidney was divided into three cortical segments (upper, middle and lower) and was scored as normal or reduced uptake. The linear correlation coefficient for the number of abnormal segments detected between planner and SPECT techniques was calculated. Results: From 200 DMSA scans, 100 scans were positive for scar in SPECT images, from which only 95 scans were positive for scar in planner imaging. Out of the five mismatched scans, three scans were for patients with renal impairment and high background activity and two scans were for very small scars. No significant difference was seen in the average number of abnormal segments detected by planar versus SPECT imaging (P = 0.31). The average correlation coefficient between was high (r = 0.91 - 0.92). Conclusions: Tc-99m DMSA renal cortical scanning using SPECT offers no statistically significant diagnostic advantage over multiple views planar imaging for detection of cortical defect.

Objectives: The rate and impact of thyroglossal duct remnant (TGDR) visualization in patients with hypothyroidism after total thyroidectomy for differentiated thyroid carcinoma (DTC) have not yet been fully determined. The aim of this study was to assess the rate of TGDR visualization in post total thyroidectomy whole body scan (WBS) for DTC and to evaluate its impact on the outcome of I-131 ablation. Methods: A total of 60 consecutive DTC patients (51 papillary thyroid Ca., and 9 Follicular thyroid Ca.), underwent total thyroidectomy, followed by WBS (using I-131 in 28 patients and I-123 in 32 patients), neck ultrasound (US), thyroglobulin (Tg) and Tg anti-bodies (TgAb) assay after 40 days and subsequent I-131 ablation. At 6 months later follow-up I-131 WBS, neck U/S, Tg and TgAb were performed following suspension of L-thyroxine for 1-month (thyroid stimulating hormone [TSH] >30 μIU/ml) in 53 patients and following recombinant human TSH stimulation in seven patients. Results: Of the studied 60 patients, 19/60 (31.7%) had a linear or focal radioactivity at the superior midline of the neck, suggesting TGDR (Group 1), and 41/60 (68.3%) had no uptake to suggest TGDR (Group 2). No significant difference regarding age, gender and histopathology between both groups. Neck US showed no evidence of thyroid tissue in the superior midline of the neck in both groups, and only a small or no residual thyroid tissue in patients of Group 1. There was a significant successful I-131 ablation rate among patients of group 1 compared to group 2 (79% in Group 1 vs. 41.5% in Group 2) (P = 0.007). Conclusions: Thyroglossal duct remnant visualization on WBS of hypothyroid subjects after total thyroidectomy suggests presence of only a small or no residual functioning thyroid tissue at the thyroid bed and can predict a good response to I-131 ablation.

Objective: Vitamin C is a vital antioxidant that may antagonize deleterious effects of smoking. The aim of this study was to evaluate the effects of administration of nicotine alone for three weeks or combined with vitamin C on the antioxidant defense status, functional, histopathological changes, and immunohistochemical demonstration of proliferating cell nuclear antigen (PCNA) in rat liver and kidney tissues. Methods: Animals were divided into four groups; (C) saline-treated, (VC) vitamin C-treated, (NIC) nicotine-treated, all were for 3 weeks, and (NIC+VC) is given vitamin C for 3 days prior, with nicotine injection and 2 days thereafter. Results: Present work showed that nicotine exposure caused significant reduction in total body weight, relative liver and kidney weights, elevated malondialdehyde (MDA), alanine transaminase (ALT), aspirate transaminase (AST), and alkaline phosphatase (ALP) in both hepatic and renal tissues. Co-exposure to nicotine and vitamin C maintained normal liver and kidney weight, significantly lowered MDA, ALT, AST, ALP and elevated glutathione in both hepatic and renal tissues compared NIC group as well as controls. Nicotine administration resulted in shedding, necrosis, and loss of brush border of cells covering proximal and distal convoluted tubules of kidney. The liver in the nicotine-treated group showed vacuolated cytoplasm of hepatocytes, with dilated central vein and sinusoids and mitochondrial destruction. Immunohistochemistry showed dense PCNA immunostaining in the livers of nicotine-treated rats. Vitamin C induced partial correction of nicotine-induced histopathological damage of liver and kidney and significant elevation in PCNA expression. Conclusion: The results of present work suggested that vitamin C has a promising prophylactic effect against nicotine-induced oxidative damage of liver and kidney.

Objective: Vitamin C is a vital antioxidant that may antagonize deleterious effects of smoking. The aim of this study was to evaluate the effects of administration of nicotine alone for three weeks or combined with vitamin C on the antioxidant defense status, functional, histopathological changes, and immunohistochemical demonstration of proliferating cell nuclear antigen (PCNA) in rat liver and kidney tissues. Methods: Animals were divided into four groups; (C) saline-treated, (VC) vitamin C-treated, (NIC) nicotine-treated, all were for 3 weeks, and (NIC+VC) is given vitamin C for 3 days prior, with nicotine injection and 2 days thereafter. Results: Present work showed that nicotine exposure caused significant reduction in total body weight, relative liver and kidney weights, elevated malondialdehyde (MDA), alanine transaminase (ALT), aspirate transaminase (AST), and alkaline phosphatase (ALP) in both hepatic and renal tissues. Co-exposure to nicotine and vitamin C maintained normal liver and kidney weight, significantly lowered MDA, ALT, AST, ALP and elevated glutathione in both hepatic and renal tissues compared NIC group as well as controls. Nicotine administration resulted in shedding, necrosis, and loss of brush border of cells covering proximal and distal convoluted tubules of kidney. The liver in the nicotine-treated group showed vacuolated cytoplasm of hepatocytes, with dilated central vein and sinusoids and mitochondrial destruction. Immunohistochemistry showed dense PCNA immunostaining in the livers of nicotine-treated rats. Vitamin C induced partial correction of nicotine-induced histopathological damage of liver and kidney and significant elevation in PCNA expression. Conclusion: The results of present work suggested that vitamin C has a promising prophylactic effect against nicotine-induced oxidative damage of liver and kidney.