The effect of preoperative Lugol's iodine on thyroid blood flow in patients with Graves' hyperthyroidism

A study was conducted to investigate the effect of Lugol's iodine on the superior thyroid artery (STA) blood flow with use of a Duplex ultrasound scanner for 12 patients with Graves' disease. All patients were treated with antithyroid drugs until they were euthyroid and then, with randomization, the patients received either Lugol's iodine, 0.3 ml thrice daily, or placebo for 9 days in a double-blind fashion. Antithyroid drugs were continued throughout the study. Reduction in the diameter, time-averaged velocity (TAV), and volume flow (VF) of the STAs was demonstrated in all patients in the treatment group, whereas there were no consistent trends in the placebo group. The changes in TAV and VF were significantly different between the placebo and treatment groups (p less than 0.01 for TAV and p less than 0.005 for VF). These changes were more marked in patients with high initial VF and minimal in patients with low initial VF. On the basis of these results, we recommend that patients with high thyroid blood flow before thyroidectomy should receive Lugol's iodine preoperatively.     

Thyroid uptake of 131-I following kippuran renal scintillation camera studies in children.

The thyroid uptake of radioactive iodine after scintillation camera studies using -131I-labeled hippuran was studied and the radiation dose calculated in 30 euthyroid children with normal renal function. Fifteen children received Lugol's solution which reduced the thyroid uptake and radiation dose significantly.     

Effect of preoperative iodine in patients with Graves'' disease controlled with antithyroid drugs and thyroxine.

Thirty-four patients with Graves' disease, first rendered euthyroid with antithyroid drugs (ATD) then given supplementary thyroxine (T4), were randomly allocated to three treatment groups. In Group I ATD and T4 were stopped 10 days before partial thyroidectomy and the patients were treated with Lugol's iodine alone. In Group II the patients were treated up to the time of operation with ATD and T4 alone. In Group III ATD and T4 were continued until the day of operation, but the patients also received 10 days' treatment with Lugol's iodine. Analysis of the results showed that pre-operative iodine therapy in patients with Graves' disease, already rendered euthyroid with ATD and T4, made no difference to the vascularity of the gland, operative blood loss or thyroid follicular size. Over a third of patients in Group I, treated with Lugol's iodine alone for 10 days pre-operatively, had subnormal levels of thyroid hormones at the time of operation and this was also the Group in which the complications of partial thyroidectomy tended to occur. It is concluded that the addition of iodine preoperatively is unnecessary in the patient who is already euthyroid on ATD and T4.     

Propranolol and thyroidectomy in the treatment of thyrotoxicosis.

For decades, the preparation of a hyperthyroid patient for surgery took several weeks or months utilizing thyroid blocking agents and iodine. In 1973, a preliminary report of 20 patients with hyperthyroidism treated with propranolol and thyroidectomy was presented. It was found that a thyrotoxic patient could be prepared for surgery, in an emergency, by intravenous propranolol in less than an hour, or electively by oral propranolol within 24 hours. Since then, 140 additional patients have been similarly treated. It continues to be true at this institution that propranolol, a beta-adrenergic blocking agent, effectively neutralizes the symptoms of autonomic hyperactivity, including sweating, tremor, fever, dilation of blood vessels, and increased pulse rate without significantly affecting thyroid function. An average dose of 160 mg/day was used, with a range of 40 to 320 mg/day. In none of these patients was iodine used; in fact, its use with propranolol is considered unnecessary. A subtotal, near total, or total thyroidectomy was done in all patients, resulting in a 55% incidence of hypothyroidism. There was no postoperative thyroid storm, nerve injury, or permanent hypoparathyroidism. It is believed that the administration of propranolol alone provides a rapid, safe, and effective preparation of the thyrotoxic patient for thyroidal or extrathyroidal surgical procedures during the perioperative period.     

Localization of abnormal parathyroid glands using thallium-201

Ectopically located parathyroid adenomas may be difficult to find during initial neck exploration. They account for over 70 percent of missed adenomas found at reexploration. Preoperative localization of parathyroid adenomas would reduce unnecessary dissection and possibly reduce the number of negative results of initial neck exploration. Before reoperative parathyroid surgery is performed, some means of localization is mandatory to detect ectopic adenomas in the neck and mediastinum. Computed tomography and ultrasonography cannot effectively evaluate the mediastinum. Angiography and venous parathyroid hormone sampling are invasive, costly, and tedious to perform. We have shown that thallium-201 will accurately localize ectopic parathyroid adenomas. All 10 adenomas found in positions not immediately adjacent to the thyroid gland were detected by thallium-201 scintigraphy. One was a mediastinal adenoma resected with a median sternotomy. Our results suggest that thallium-201 scintigraphy should be the initial localization procedure of choice before all reexplorations. Its use before initial explorations, as well, will enable the surgeon to immediately direct attention to the area of the localized adenoma. If mediastinal uptake is found to be present, then median sternotomy may be performed during initial surgery provided a thorough neck exploration is performed first.     

Effect of silicone breast implants on myocardial imaging

The authors investigated the effect of silicone breast implants (SBIs) on thallium-201 myocardial perfusion scintigraphy. Twenty-nine patients with SBIs and 14 control subjects were included in the study. All of the participants underwent a resting thallium-201 myocardial perfusion study. Comparison of the thallium images between patients with SBI and control subjects was done both visually and semiquantitatively. On visual analysis, neither image distortion nor image artifact attributable to the SBIs was noted. Semiquantitative analysis revealed that in patients with SBIs, the uptake values of the anteroseptal, anterolateral, lateroanterior, and lateroinferior myocardial walls was slightly, but significantly, lower than those of control subjects: anteroseptal, 87.7+/-6.0% vs. 92.8+/-5.1%; anterolateral, 88.0+/-5% vs. 92.6+/-4.5%; lateroanterior, 87.4+/-5% vs. 91.4+/-4.7%; and lateroinferior, 86.0+/-6.0% vs. 91.7+/-7.0%. The uptake value of the remaining walls in patients with SBIs were not significantly different than the control subjects. In conclusion, SBIs did cause a significant decrease in uptake values of the myocardial walls, which should be considered during interpretation of the images.     

Increased iodine uptake in thyroid carcinoma after treatment with sodium butyrate and decitabine (5-Aza-dC).

OBJECTIVE: To determine if epigenetic-modifying drugs can increase iodine uptake in thyroid carcinoma cell lines. STUDY DESIGN: Human thyroid carcinoma cell lines were tested for iodine uptake before and after treatment with epigenetic-modifying agents. RESULTS: Thyroid carcinoma cell lines DRO and 2-7 had high levels of DNA methylation (74% and 80%) compared with normal thyroid tissue (6%) (P < 0.05). This finding correlated with low levels of sodium iodide symporter (NIS) expression in the untreated thyroid carcinoma cell line. Combination treatment with the epigenetic-modifying agents 5-aza-2'-deoxycytidine and sodium butyrate resulted in increases in NIS messenger RNA levels, global histone acetylation, and 9- and 8-fold increases in I(125) uptake for the DRO and 2-7 cells, respectively. CONCLUSIONS: Epigenetic-modifier drugs represent a novel adjuvant treatment for those patients with radioablation-resistant thyroid cancer. SIGNIFICANCE: Epigenetic-modifying agents show potential for treatment of radioablation-resistant thyroid cancer.     

Utility of fluorine-18-fluorodeoxyglucose positron emission tomography in differentiated thyroid carcinoma with negative radioiodine scans and elevated serum thyroglobulin levels

BACKGROUND: This study aimed to determine the role of fluorine-18-fluorodeoxyglucose positron emission tomography (FDG-PET) in the follow-up of patients who underwent total thyroidectomy and iodine-131 ((131)I) ablation therapy for differentiated thyroid cancer and presented increased thyroglobulin levels with negative (131)I and thallium-201 ((201)Tl) scans. METHODS: Two patients with follicular carcinoma and eight with papillary tumors underwent total thyroidectomy and (131)I therapy until the (131)I scan was negative. (131)I and (201)Tl scans were performed with negative results in all cases, while serum thyroglobulin measurements were all positive with negative thyroglobulin autoantibodies. One week after the (131)I scans, all the patients underwent FDG-PET whole-body scans. RESULTS: The FDG-PET scan detected in 4 patients, a single focal increase of FDG uptake in one lymph node metastasis (subsequently confirmed histologically); in 1 patient, multiple pathological focal uptakes in brain, neck, and chest; and in 1 patient, two mild focal uptakes in the mediastinum, close to the tracheal branch. In 2 other patients, pathological FDG uptakes in cervical spine and mediastinum were not confirmed by other imaging techniques, and in the 2 remaining patients the scan results were inconclusive. The sensitivity of FDG-PET whole-body scan for detecting metastatic thyroid cancer was 60%. CONCLUSIONS: This study indicates that the FDG-PET whole-body scan is a useful tool in the follow-up of patients with differentiated thyroid cancer, negative (131)I and (201)Tl scans and elevated serum thyroglobulin levels. The FDG-PET scan detects metastatic disease in 60% of patients with differentiated thyroid cancer, enabling surgical therapy to be performed on accessible lesions.     

Iodine-induced thyrotoxic hypokalemic paralysis after ingestion of Salicornia herbace

A 56-year-old Korean man visited to emergency room due to paroxysmal flaccid paralysis in his lower extremities. There was no family or personal history of periodic paralysis. His initial potassium levels were 1.8?mmol/L. The patient had been taking Salicornia herbacea for the treatment of diabetes and hypertension. Results of a thyroid function test were as follows: T3?=?130.40?ng/dL, TSH?=?0.06?mIU/L, and free T4?=?1.73?ng/dL. A thyroid scan exhibited a decreased uptake (0.6%). His symptoms clearly improved and serum potassium levels increased to 4.4?mmol/L by intravenous infusion of only 40?mmol of potassium chloride. Eight months after the discontinuation of only Salicornia herbacea, the patient’s thyroid function tests were normalized. Large amounts of iodine can induce hypokalemic thyrotoxic paralysis and it may be necessary to inquire about the ingestion of iatrogenic iodine compounds, such as Salicornia herbacea.     

A new method of conduction system staining

Visualization of the conduction bundle is advantageous in the prevention of surgical trauma to the conduction system during open-heart surgery. Because vital staining using an iodine starch complex has been known to result in tissue damage, we have evaluated the effects of iodine gas on the specialized conduction system. The conduction bundle was stained, well enough to be identified, with iodine tincture, with Lugol's solution, and with iodine gas. However, all these agents except for iodine gas caused marked electrophysiological changes. Similar changes occurred with the use of ethanol and of 10% potassium iodine solution, which are the solvents of iodine tincture and Lugol's solution, respectively. Microscopic examination showed that iodine tincture, Lugol's solution, and their solvents caused marked histological changes in the conduction tissue. However, no significant changes in the conduction tissue were noted from iodine gas spraying. Therefore, tissue damage caused by iodine tincture and Lugol's solution was thought to be due not to a reaction to the iodine starch complex itself, but to their solvents. In a long-term experimental study of 10 dogs, we found that iodine gas caused no electrophysiological disturbances or damage of microscopic tissue. Of the agents we tested, only iodine gas is free from harmful effects and can be used clinically.     

卢戈液染色与p53蛋白检测诊断早期食管癌的可行性研究

目的　验证内镜下卢戈液染色和活组织p5 3检测 ,诊断食管早期癌和表浅癌的可行性。方法　将 97例食管癌手术标本先用卢戈液染色 ,然后对粘膜不着色区行p5 3蛋白免疫组化染色。结果　共有 6 3处直径大于 2mm的粘膜不着色区 ,其中正常粘膜 2处 ,单纯增生 7处 ,不典型增生 42处 ,原位癌 1处 ,鳞状细胞癌 11处 ;p5 3蛋白的阳性表达主要发生在重度不典型 (42 3% )和鳞状细胞癌 (45 5 % )的细胞核内 ,而在正常粘膜、单纯增生和轻至中度不典型增生组织中几乎无表达 (P <0 0 5 )。结论　内镜下卢戈液染色和活组织p5 3检测诊断食管早期癌和表浅癌的设想具有可行性。     

The value of color flow Doppler ultrasonography of the superior thyroid artery in the surgical management of Graves disease

HYPOTHESIS: The factors affecting blood flow within the hypervascular thyroid gland and the effect of vascularization on the preparation for thyroidectomy as treatment for Graves disease can be documented. DESIGN: Blood flow through the superior thyroid arteries of patients with Graves disease, maintained in a euthyroid status, was measured by color flow Doppler ultrasonography. The microvessel density was assessed immunohistochemically using the level of expression of factor VIII in tissue sections. Both the thyroid gland's weight and blood loss volume were measured during the operation. SETTING: Tertiary care teaching hospital. PATIENTS: Fifty-two patients with Graves disease undergoing thyroidectomy. RESULTS: The blood flow rate was significantly correlated with thyroid weight (P<.01), thyroid microvessel density (P<.001), and histopathologic microscopic pattern (P<.001). The relation between these factors could be expressed as follows: Blood flow (mL/min) = [[0.0158 + 0.00136] x (weight (g) x microvessel density)](1/2) (R2 = 0.64, P<.001). Diffuse microfollicular hyperplastic thyroid tissue had a significantly higher blood flow and vascular density than tissue having an inactive colloid pattern (P<.01). Ten patients having a blood loss exceeding 200 mL during thyroidectomy showed a higher preoperative blood flow rate and microvessel density (P<.01). Of 8 patients whose blood flow was more than 0.15 L/min, 6 (75%) had blood loss in excess of 200 mL during surgery. CONCLUSIONS: The blood flow of the superior thyroid artery is positively related to intrathyroid microvessel density, glandular weight, and histopathologic microscopic pattern. Preoperative color flow Doppler ultrasonography may help in identifying patients with Graves disease who are liable to bleed intraoperatively during thyroidectomy.     

Iodine retention and thyroid dysfunction in patients on hemodialysis and continuous ambulatory peritoneal dialysis

Povidone-iodine is frequently used as an antiseptic in patients on chronic dialysis. In order to determine if the use of povidone-iodine affects thyroid function in these patients, we measured serum iodine and thyroid hormone levels in dialysis patients prior to and following discontinuation of topical povidone-iodine antiseptics. Serum inorganic iodine levels were elevated initially in nearly 90% of the patients (19 on hemodialysis, 12 on continuous ambulatory peritoneal dialysis [CAPD]). Following discontinuation of povidone-iodine, iodine levels over a 3-month period decreased modestly in patients on CAPD (n = 5) and were unchanged in patients on hemodialysis (n = 5). Total and free thyroxine levels were frequently low but did not correlate with protein-bound or inorganic iodine levels and did not change after discontinuation of povidone-iodine. Thyrotropin levels correlated significantly (r = .62, P less than .01) with inorganic iodine levels in patients on hemodialysis, but not for patients on CAPD. We conclude that abnormal thyroid function tests are common in dialysis patients but are not related to iodine retention or to the routine use of topical povidone-iodine-containing antiseptics.     

Thyroid cancer with concurrent hyperthyroidism

OBJECTIVE: To study the clinical manifestation, outcome, and factors predicting metastases in patients with thyroid cancer and concurrent hyperthyroidism. DESIGN: Retrospective study of 37 thyrotoxic patients with differentiated carcinomas of the thyroid who were operated on between 1979 and 1995. The follow-up period ranged from 562 days to 14 years 9 months (mean +/- SE, 2093+/-201 days). SETTING: University hospital with an annual performance rate of about 700 thyroid operations. PATIENTS: Thyroidectomy was performed in 37 patients (31 women and 6 men), including 33 papillary carcinomas and 4 follicular carcinomas. The mean +/- SE age of the patients was 38.6+/-2.2 years. RESULTS: The mean +/- SE diameter of tumors was 13.2+/-0.9 mm (range, 2-67 mm). The tumor size in 25 patients (68%) was 10 mm or smaller. Subtotal thyroidectomy (21 patients), total thyroidectomy (8 patients), near-total thyroidectomy (4 patients), and completion thyroidectomy (4 patients) were performed. Twenty-eight patients underwent postoperative sodium iodide I 131 (131I) ablation for thyroid remnant. There was 1 local recurrence, 3 metastases to regional neck lymph nodes, and 3 distant metastases. A patient with follicular carcinoma died of metastases at 3 years 4 months after thyroidectomy. Age, sex, duration of thyrotoxic symptoms, tumor size, histopathological findings, type of goiter, extent of surgery, 131I ablation, and 6-week postoperative serum concentrations of thyroglobulin or thyrotropin were not significant factors in predicting metastases. Serum levels of triiodothyronine and thyroxine before antithyroid treatment in the patients with metastases were significantly higher than in those without metastases. CONCLUSION: The majority of patients with thyroid cancer and concurrent hyperthyroidism have small carcinomas.     

Detection of recurrent gliomas with quantitative thallium-201/technetium-99m HMPAO single-photon emission computerized tomography.

Deteriorating clinical status after high-dose radiation therapy for high-grade gliomas may be due to radiation changes or may signal recurrent or residual tumor mass. The two conditions cannot be distinguished reliably by computerized tomography (CT) or magnetic resonance (MR) imaging. The authors assessed the ability of sequential thallium-201 chloride (201Tl) and technetium-99m hexamethylpropylene amine oxime (99mTc HMPAO) single-photon emission CT (SPECT) to distinguish tumor recurrence from radiation changes after high-dose (greater than or equal to 600 cGy) radiation therapy for malignant gliomas. Preoperative tumor/nontumor uptake ratios were analyzed in 32 patients and correlated with the presence of gross tumor at the time of reoperation. In 12 of 13 patients with 201Tl tumor/scalp ratios of 3.5 or greater, recurrent tumor was present. The authors found 99mTc HMPAO SPECT to be useful for identifying the absence of solid tumor recurrence in patients with low to moderate 201Tl uptake (ratio 1.1 to 3.4) and low perfusion to that site. In 11 of 12 patients with 99mTc HMPAO tumor/cerebellum ratios of 0.50 or less, no recurrent tumor mass was present. Three of seven patients with 201Tl ratios of 3.4 or less and 99mTc HMPAO ratios of 0.51 or more had recurrent tumor found at surgery; thus the test was not predictive in this group. It is concluded that the use of sequential 201Tl and 99mTc HMPAO SPECT accurately identifies the presence of tumor recurrence versus radiation changes in most patients with high-grade astrocytomas who have undergone tumor resection and high-dose radiation therapy.     

Thyrotoxicosis--surgical management in the era of evidence-based medicine: experience in western India with 752 cases

The three modalities of treatment of thyrotoxicosis, antithyroid therapy (ATT), radio-iodine (I131) therapy and surgery are not cause-specific. In this paper, we describe our evolving experience with 752 thyrotoxic patients who underwent surgery during the last 40 years and discuss the current scenario with evidence-based data and observations wherever possible. Thyroidectomy was performed in 428 patients with Grave's disease (GD), 299 patients with toxic multinodular goitre, and 25 with toxic solitary nodules (TSN). Whereas 289 patients with GD had surgery for failed ATT, the other 139 had primary surgery for controversial or debatable indications such as poor socio-economic status, desire for early pregnancy, poor drug compliance and severe ophthalmopathy. Preoperatively, all patients were administered carbimazole or propylthiouracil. Non-selective b-blocker propranolol and Lugol's iodine were routinely given. In the 25 patients with TSN, hemithyroidectomy was performed. In all others, subtotal thyroidectomy (STT), was performed leaving behind 4 to 8 g of thyroid tissue: a larger amount was left behind in those with higher antithyroid antibody titres. During the last decade, 80 patients received near total thyroidectomy (NTT), mainly to minimize recurrence of thyrotoxicosis and to ameliorate severe eye signs. Because of our increasing experience, no significant increase in postoperative morbidity was encountered with NTT compared to STT. Transient hoarseness was observed in 53 patients with STT and only in two patients with NTT. Three patients with STT and one with NTT developed permanent hoarseness due to recurrent laryngeal nerve palsy; voice in these four was normalized by intraglottic injection of Teflon paste 6 months after the operation. In patients undergoing STT, transient hypoparathyroidism was encountered in 63, and permanent hypoparathyroidism in five. The corresponding figures for NTT were 12 and one, respectively. Of the 500 patients monitored for 1 year or more, hypothyroidism was observed in 135 and recurrent thyrotoxicosis in nine. In the same group of 500, exophthalmos was ameliorated in 130 of the 265 with positive eye signs. Nineteen glands exhibited features of severe Hashitoxicosis with marked destruction of acini and considerable lymphoid aggregates and follicles. Carcinoma was observed in three other thyroid glands.     

Hyperthyroidism due to excess iodine

TWO TYPES: Hyperthyroidism may develop in around 10% of patients in excess iodine. It may reveal an undetected pretoxic thyroid disease (type I) or have been induced by excess iodine in previously normal thyroid gland or in an euthyroid goiter (type II). IODINE EXCESSE REVEALING THYROTOXICOSIS: In the former situation, symptoms appear shortly after the iodine load, thyroid scintigraphy shows significant uptake and therapy includes discontinuation of iodine excess, antithyroid drugs, potassium perchlorate and, if necessary, thyroidectomy or a therapeutic dose of iodide 131. IODINE-INDUCED THYROTOXICOSIS: In the latter situation (type II) hyperthyroidism may occur several years after the initiation of iodine excess, scintigraphy shows very low or no uptake, spontaneous remission is observed within six months, despite the persistence of iodine excess, and treatment is based on corticosteroids.     

Comparison of blood flow and cell function in ischemic skin flaps

Cellular function and blood flow in acute, steroid-treated, and surgically delayed random skin flaps have been examined. In these studies, the period following flap elevation could be divided into early (0–2 hr), intermediate (4–6 hr), and late (12 hr) periods of ischemia, based on the cutaneous blood flow and cellular function measured by thallium-201 uptake. There was a close correlation (r = 0.98, 2 hr) between blood flow and cellular function during the early period of ischemia which became worse with time (r = 0.78, 12 hr). Blood flow studies demonstrated a significant difference (P < 0.05) between the early and intermediate periods of ischemia which was abolished by surgical delay. Improvement in cellular function was accomplished by improved blood flow in the surgically delayed flaps, while steroid-treated flaps enhanced cellular metabolism by another mechanism. Cellular function approximated blood flow during the early and immediate period of ischemia. Steroids may augment cellular function without improving blood flow, while surgical delay improves cellular function by improving blood flow.     

Thallium-201 washout rate of stress myocardial perfusion imaging as a predictor of mortality in diabetic kidney disease patients initiating hemodialysis: an observational,follow-up study

Background

Thallium-201 washout rate of stress myocardial perfusion imaging (MPI) has been reported to correlate with coronary flow reserve which is a parameter of myocardial microcirculation. However, the evidence for its use in diabetic kidney disease (DKD) has been lacking, and the association between thallium-201 washout rate and adverse outcomes including death is unknown. Therefore, the present study was conducted to evaluate the predictive ability of thallium-201 washout rate for mortality in DKD patients initiating hemodialysis.

Methods

A total of 96 patients with type 2 diabetes who had been started on maintenance hemodialysis undergoing stress MPI with thallium-201 within 1 year, 72 men and 24 women, with a median age of 67 years, were studied. The endpoint was defined as all-cause death. The Cox proportional hazards model was used to calculate hazard ratios (HR) and 95% confidence intervals (CI).

Results

During the mean follow-up period of 3.4 ± 2.1 years, 18 (18.8%) deaths occurred. Cumulative survival rates during the follow-up period, with thallium-201 washout rate levels in the lowest tertile (3.1–36.2%), the middle tertile (36.5–46.3%), and the highest tertile (46.4–66.2%), were 51.0, 86.5, and 85.3%, respectively. Overall, the multivariate Cox regression analysis revealed that thallium-201 washout rate remained an independent predictor of death after adjusting by confounding variables (HR 0.91, 95% CI 0.85–0.97).

Conclusions

Among DKD patients initiating hemodialysis, thallium-201 washout rate seems to be useful for predicting death.