Volume Of Thyroid Tissue Research Articles

Current status of the thyroid hormone measurement items in patients receiving levothyroxine monotherapy by the management based on the thyroid tissue volume.

We and other investigators reported that mild TSH suppression with levothyroxine (LT4) was needed to achieve normal free triiodothyronine (FT3) levels and metabolic euthyroid state in athyreotic patients. Consequently, management methods based on thyroid tissue volume have been implemented for patients receiving LT4 at the Kuma Hospital. This retrospective study examined the composition of the thyroid hormone measurement items (serum-free thyroxine [FT4], FT3, and FT4 + FT3) in patients receiving LT4 monotherapy. According to the etiology of hypothyroidism, 36% of the 25,523 patients included in this study underwent total thyroidectomy (TT). Thirteen percent and 14% had undergone 131I treatment for hyperthyroidism (RIT) and partial thyroidectomy (PT), respectively. Moreover, 37% of patients had received non-invasive treatment (NIT). The proportion of patients who underwent only FT3 measurements was higher (TT, 93%; RIT, 61%) in the first two groups, whereas the proportion of patients who underwent only FT4 measurements was higher (PT, 50%; NIT, 65%) in the remaining two groups. Only FT3 measurements were performed in 58% of patients. Only FT4 measurements were performed in 34% of patients. The serum TSH levels were suppressed in nearly half of the patients (46%). Thus, FT3 was the major thyroid hormone measured in patients receiving LT4 treatment, and the serum TSH levels were suppressed in nearly half of the patients. This may be attributed to the management guidelines at our hospital, a specialized facility for thyroid disease, wherein half of the patients present are athyreotic or have atrophic thyroid glands after TT or RIT.

Efficiance of radioiodine remnant ablation in cases of locally differentiated thyroid cancer

On the territory of Russia has increased the of thyroid cancer after Chernobyl NPP incidence at 1986, and currently accounts for up to 14,000 newly identified cases. Postoperative radioiodine (RAI) remnant ablation is the second stage of combine treatment of differentiated thyroid cancer, except for the prevalence of pT1N0M0, with minimal level of TG and AT-TG, according to international guidelines. In the past 20 years a significant number of published practice guidelines for the treatment of this disease. However, the discussion is the amount of medication for administration activity (GBq) 131I, is required for successful ablation of thyroid remnants. The study analyzed 353 clinical cases after radical surgical treatment for DTC. In our study, the effectiveness of radioiodablation was compared with certain indicators of specific therapeutic activity 131I (MBq/kg), in groups of patients with different levels of TSH stimulation (less than 30 mME/ml, and more than 30 mME/ml). We evaluated the absorbed dose in the thyroid remnant in patients with residual thyroid tissue volume determined by US when administering 131I empirical therapeutic activity. The control of the WBS with 131I was carried out in 6 months. The average eղciency RAI was 85.5 %, there were no significant differences in the TSH stimulation groups of more than 30 mME/ml and 4-30 mME/ml (p > 0.05). If the thyroid remnant is not detected by US, the effective range of 131I specific therapeutic activity is 30-40 MBq/ kg against a background of TTG stimulation greater than 4 ՏME/ml and strict adherence to a 14-day low iodine diet. Direct radiometry followed by neck scintigraphy (1200 kBq 131I) and calculation of therapeutic activity is recommended when determining thyroid remnant by US to plan for TAD = 300 Gy and reduce the risk of radiation sialoadenitis. At the time of RAI, 3.9 % of patients had previously undetectable X-rays lung metastases with stimulated TG levels greater than 124 ng/mL after surgical treatment with SPECT/CT.

Computed Tomography Findings Affecting the Decision of Sternotomy in Substernal Goiter.

Although thyroidectomy is completed with a cervical incision in most patients with substernal goiter (SG), sternotomies may be required occasionally. The purpose of this study is to examine computed tomography (CT) findings that may predict the need for sternotomy in SG surgery. Neck-thoracic CT images of patients who underwent total thyroidectomy with the diagnosis of SG between 2013 and 2022 were retrospectively examined. The patients (n=41) were divided into two groups: sternotomies (n=6) and cervical (n=35). Preoperative pathological data, CT findings, and postoperative complications of the patients were recorded. The total thyroid volume of the sternotomy group (280.75±127.01 mm3) was significantly greater than that of the cervical group (155.38±74.18 mm3) (p=0.015). The retrosternal thyroid volume (mm3), thyroid craniocaudal, and anterior-posterior dimensions (mm) were significantly greater in the sternotomy group (p=0.001, p<0.001, and p=0.004, respectively). While the majority of mediastinal extension degrees in the cervical group were grade 1 (80%), grade 2 (83%) predominated in the sternotomy group (p=0.001). The radiological findings of total thyroid volume, retrosternal thyroid tissue volume, retrosternal thyroid length, thyroid anterior-posterior dimension, and mediastinal extension degree on CT are valuable in predicting the decision to perform a sternotomy in SG surgery.

A Multiplex Thyroid-Specific Assay for Quantification of Circulating Thyroid Cell-Free RNA in Plasma of Thyroid Cancer Patients.

BackgroundThe standard of care for thyroid cancer management is thyroidectomy and adjuvant radioactive iodine (RAI). There is a paucity of clinical tool that quantifies residual thyroid volume reliably for precise adjuvant RAI dosing. Serum thyroglobulin (TG), tumour marker for thyroid cancer, takes 4 weeks for complete clearance due to its long half-life, and might be undetectable in 12% of structural disease patients. It detects recurrence with a sensitivity of 19–40%, mainly attributed to issue of TG antibody interference with TG immunometric assay. We hypothesise that the quantity of thyroid-specific cell-free RNA (cfRNA) is indicative of amount of thyroid tissues, and that during thyroid surgery, cfRNA levels decrease accordingly.MethodsWe identified 11 biologically significant and highly expressed thyroid-specific targets from Human Protein Atlas and literature. To assess for a fall in thyroid-specific cfRNA level, we recruited 16 patients undergoing thyroid surgery or RAI for malignant or benign thyroid disease, and tracked longitudinal trend of cfRNA. To assess the utility of cfRNA in detecting metastatic thyroid cancer, cfRNA of 11 patients at intermediate to high risk of recurrence was measured during surveillance and at time of clinical recurrence.ResultsThe multiplex assay was capable of amplifying and quantifying multiple thyroid-specific genes in a single reaction. The selected targets were amplified successfully from RNA extracted directly from the thyroid (positive control), indicating that they were highly expressed within thyroid tissue. These cfRNAs were present in plasma, in amounts quantifiable using qRT-PCR. Four cfRNA transcripts (TPO, GFRA2, IVD, TG) fell post-treatment in more than 50% of cohort. The thyroid peroxidase (TPO) cfRNA fell post-therapy in 63% of cohort by 80%, as early as 1 day post-treatment, supporting the potential role as early indicator of remnant thyroid tissue volume. We demonstrated the clinical relevance of circulating TPO cfRNA by tracking temporal changes in setting of peri-treatment, recurrence, and TG Ab positive state.ConclusionUsing a multiplex pre-amplification approach, the TPO cfRNA was a potential biomarker that can track residual thyroid mass. It can be further optimised for quantification of thyroid volume to guide RAI doses and for detection of thyroid cancer recurrence.

Analysis and evaluation of the efficacy of ultrasound-guided microwave ablation for papillary thyroid microcarcinoma

Objective The choice of the most appropriate therapeutic approach for a diagnosed papillary thyroid microcarcinoma (PTMC) remains controversial. The present study aimed to evaluate the efficacy of microwave ablation (MWA) for unifocal PTMC with a diameter of ≤0.6 cm. Methods A total of 63 consecutive patients with PTMC treated with MWA were studied retrospectively. MWA was performed using the hydrodissection technique and multidimensional fixed-needle principle. We analyzed the absorption of the MWA area and evaluated the prognosis over a follow-up period of 24 months. In addition, 83 patients with PTMC who underwent surgery were selected. The operating room characteristics and procedural complications of the two groups were compared. Results In the MWA group, the volume of nodules (p < 0.05) decreased from 0.04 ± 0.03 cm3 to 0.0001 ± 0.0004 cm3 at the 24-month follow-up after MWA, and the volume reduction rate (p < 0.05) was 99.43 ± 1.58%. The incidence of temporary reactive hyperplastic lymphadenectasis was higher and that of other complications was lower in the MWA group than in the surgery group. One percent of the patients in the surgery group had recurrence or metastasis, but none were detected in the MWA group. The loss of thyroid tissue volume (p < 0.001), operating room time (p < 0.001), and the mean length of hospital stay (p < 0.001) were significantly lower in the MWA group than in the surgery group. Conclusion Ultrasound-guided MWA is an effective treatment strategy for unifocal PTMC with a diameter of ≤0.6 cm.

Parathyroid Hormone Level Changes Following Radioiodine Therapy for Thyroid Cancer: A Prospective Observational Study

ObjectiveOur objective was to analyze the effect of radioiodine (RAI) therapy on parathyroid hormone (PTH) secretion. MethodsA total of 137 patients were included and divided into 2 groups based on pretherapy PTH levels. The residual thyroid tissue volume was classified into 4 grades (0-3), and a value of 0 indicated that there was no apparent residual tissue. We analyzed the PTH level changes among different time points in each group and the factors that could predict the PTH level changes. ResultsIn 113 patients with normal parathyroid gland function, the PTH level at baseline, 1 day, 7 days, 1 month, 3 months, and 6 months after RAI therapy did not show any significant difference; in 24 patients with decreased parathyroid gland function, the level of PTH immediately decreased after the implementation of RAI therapy but gradually returned to a pre-RAI therapy level within 6 months. On the seventh day after therapy, the mean value of PTH in patients with a residual thyroid tissue volume of extent of 0/1 was 8.0 ± 2.3 pg/mL, which was significantly higher than that in patients with a residual thyroid tissue volume of extent of 2/3 (P = .011). Similar phenomena were observed 1 month, 3 months, and 6 months after therapy. ConclusionRAI therapy had a significant transient adverse effect on parathyroid gland function in patients with decreased PTH secretion pretherapy, and the extent was associated with the amount of residual thyroid tissue.

Results of sclerotherapy for recurrent and non-recurrent nodular goiter

Background. The problems of treating recurrent nodular goiter are still relevant. The technical difficulties of the intervention on the neck tissues altered by the scarring process and the comorbid background of patients cause an unacceptably high risk of complications of traditional surgical treatment and, as a result, a long and difficult rehabilitation period and high costs for the treatment of patients who have undergone surgery for recurrent goiter. Alternative methods, such as sclerotherapy, which reduce the risk of complications, have been successfully used in patients with non-operated thyroid, but the possibilities of minimally invasive destruction of recurrent nodules have not been studied enough, and it is not known whether it is as safe and effective as sclerotherapy of non-recurrent nodules. The aim of the study was to compare the efficacy and safety of treatment of recurrent and non-recurrent nodular goiter using sclerotherapy. Materials and methods. The study included 30 previously not operated patients with nodular goiter and 30 patients with recurrent nodular goiter. All of them underwent 4 courses of sclerotherapy, each of which included 5 sessions with a frequency of 1 session per week; polidocanol was used as a sclerosant. Results. The analysis showed that the efficiency of reduction of nodules did not decrease in patients with recurrent goiter, despite severe sclerotic changes in the tissues. The size of the nodules and the volume of thyroid tissue were reduced during sclerotherapy, regardless of the presence of a history of thyroid surgery, as well as the cure of functional autonomy and relief of symptoms of neck compression. The tolerability of sclerotherapy also did not depend on the presence of recurrent goiter, and the rate of complications was the same (0.8%). Complications of sclerotherapy were not serious in any case. Conclusions. Thus, sclerotherapy of recurrent nodules is a good alternative to traditional surgical treatment; it is not inferior in efficiency and safety to sclerotherapy of nodules in a non-operated thyroid. Its use will significantly reduce the rehabilitation period and the cost of treating patients with recurrent nodular goiter.

Iodine concentration and content measured by dual-source computed tomography are correlated to thyroid hormone levels in euthyroid patients: a cross-sectional study in China

BackgroundThe aim of this study was to investigate the correlation of the dual energy CT measured iodine concentration and total iodine content with blood measured thyroid parameters.MethodsForty-three patients with normal thyroid function at our hospital from August 2017 to October 2019 were included in this retrospective study. Dual energy CT was used to scan the neck of thyroid patients. The mean iodine concentration and thyroid tissue volume were measured to calculate the total iodine content of the thyroid. Relevant tests of triiodothyronine (FT3), total triiodothyronine (TT3), total thyroxine (TT4), free thyroxine (FT4), and thyroid hormone (TSH) were conducted. The correlation of the thyroid mean iodine concentration and total iodine content with blood-measured thyroid function was analysed.ResultThe total iodine content in the thyroid was positively correlated with FT3 but negatively correlated with TSH. The mean iodine concentration of the thyroid was positively correlated with both FT3 and TT3.ConclusionThe thyroid iodine content measured by dual energy CT can be used to determine the human iodine nutritional status and evaluate thyroid function, which will facilitate the diagnosis and treatment of thyroid diseases.

Temporal Changes in Thyroid Nodule Volume: Lack of Effect on Paranodular Thyroid Tissue Volume.

The term "nodular goiter" has long been used to refer to a nodular thyroid gland, based on the assumption that nodule growth may be associated with hyperplasia of the surrounding non-nodular tissue. The aim of this prospective, multicenter, observational study was to determine whether nodule growth is accompanied by growth in the non-nodular tissue. Eight Italian thyroid-disease referral centers enrolled 992 consecutive patients with one to four benign nodules. Nodular and non-nodular thyroid tissue volumes were assessed for five years with annual ultrasound examinations. In participants whose nodules remained stable (n = 839), thyroid volumes did not change (baseline 15.0 mL [confidence interval (CI) 14.5-15.6]; five-year evaluation 15.1 mL [CI 14.5-15.7]). In participants with significant growth of one or more nodule (n = 153), thyroid volumes increased and by year 5 were significantly greater than those of the former group (17.4 mL [CI 16-18.7]). In 76 individuals with unilateral nodules that grew, the mean nodular lobe volume significantly exceeded that of the contralateral lobe (8.6 mL [CI 7.4-9.8] vs. 6.7 mL [CI 6-7.4]). The unaffected lobe volumes remained stable over time, while nodular lobes grew steadily and were significantly greater at the end of follow-up (10.1 mL [CI 8.9-11.3]). Excluding the volume of the largest growing nodule in these cases, the remaining volume of the affected lobe remained virtually unchanged with respect to its baseline value. Furthermore, there was no significant difference in the non-nodular tissue volume between the unaffected lobe and the affected lobe (with the largest growing nodule volume subtracted), both at baseline and at the end of follow-up. The growth of thyroid nodules is a local process, not associated with growth of the surrounding non-nodular tissue. Therefore, a normal-sized thyroid containing nodules should be referred to as a "uni- or multinodular thyroid gland" and considered a distinct entity from "uni- or multinodular goiter."

Postoperative hypothyroidism after thyroidectomy for nontoxic multinodular goiter: Can we prevent it by leaving more?

Introduction: A study was done to evaluate the function of the thyroid remnant after subtotal and near total thyroidectomy (STT and NTT) in nontoxic multinodular goiter (MNG) by using radioactive iodine uptake (RAIU) and serum thyroid stimulating hormone (TSH), after leaving variable amounts of remnant thyroid tissue. Materials and Methods: A prospective study included 25 patients with nontoxic MNG over a period of 18 months where in STT and NTT was performed. Depending on the availability of the normal thyroid tissue found intraoperatively, a definite volume of thyroid tissue was left in the tracheoesophageal groove along the recurrent laryngeal nerve. Serum TSH and RAIU were performed 4 weeks after surgery. Patients were divided into three groups A, B, and C depending on the size of thyroid remnant left during surgery that is a volume of 5 mL, respectively. Results: There is no statistical significant correlation seen between the size of the remnant thyroid tissue, hypothyroidism, and the postoperative serum TSH value. RAIU study conducted at 4 weeks postsurgery showed no correlation between the volume of the thyroid tissue remnant and its RAIU uptake. Conclusion: The thyroid function of the patients after thyroidectomy does not depend on the volume of the thyroid remnant left. There may be many other factors which determine the thyroid function like the total preoperative gland mass, histopathological nature of the gland, sex, and preoperative thyroid function.

Effects of drugs on the efficacy of radioiodine (|) therapy in hyperthyroid patients.

The treatment of hyperthyroidism is targeted at reducing the production of thyroid hormones by inhibiting their synthesis or suppressing their release, as well as by controlling their influence on peripheral tissue (conservative therapy, medical treatment). Radical treatment includes surgical intervention to reduce the volume of thyroid tissue or damage of the mechanisms of thyroid hormone synthesis by radioiodine (131|) administration. Radioiodine (131|) is a reactor radionuclide, produced as a result of uranium decomposition and emission of β and γ radiation. The therapeutic effects of the isotope are obtained by the emission of β radiation. In the paper, the effects of administered drugs (antithyroid, glucocorticosteroids, lithium carbonate, inorganic iodine, β-blockers) on the final outcome of radioiodine therapy in patients with hyperthyroidism are discussed.

Use of helical computed tomography for measurement of thyroid glands in clinically normal cats

To determine the dimensions and volume of thyroid tissue in clinically normal cats by use of computed tomography. 8 cats. Helical computed tomography images (2-mm collimation) were acquired from the cranial aspect of the second cervical vertebra through the caudal aspect of the fourth cervical vertebra. Data were acquired before contrast medium administration (n = 7 cats) and immediately after contrast medium enhancement (1 cat). Length, width, and height measurements of each thyroid lobe were made by use of transverse, dorsal, and sagittal plane images. Thyroid lobe volume was estimated by use of 3 methods. All thyroid lobes were histologically normal. Mean dimensions for a thyroid lobe were 16.5 x 2.00 x 4.31 mm (length x width x height) using only data from transverse images. Mean thyroid lobar volume was 113.75 mm(3) using the sum of areas method. Mean total volume of thyroid tissue was 215.25 mm(3) using the sum of areas method. Results may be useful for computed tomography evaluation of abnormal thyroid glands in cats, which warrants investigation.

Analysis of Tg Transcripts by Real-Time RT-PCR in the Blood of Thyroid Cancer Patients

Serum Tg (sTg) assays are sometimes unsatisfactory for monitoring thyroid cancer because interference caused by anti-Tg antibodies may reduce the sensitivity of the tests during thyroid hormone therapy. We have therefore developed a complementary method using real-time quantitative RT-PCR based on the amplification of Tg mRNA. Two different pairs of primers were used for the determination of the frequency of one of the variants of the alternative splicing of Tg mRNA. The frequency of this variant was as high in patients (n = 40) as in controls (n = 30), accounting for about 33% of the total Tg mRNA. Using appropriate primers, we observed that Tg mRNA values in controls varied according to the volume of thyroid tissue and the TSH concentration. The Tg mRNA values allowed the definition of a positive cutoff point at 1 pg/microg total RNA. This cutoff point, tested on the group of patients treated for thyroid cancer, produced fewer false negative results than those obtained with sTg assays. The standardized, highly sensitive real-time RT-PCR technique may therefore prove useful as a complement to sTg assays, particularly for patients with recurrent thyroid cancer receiving T(4) therapy.

Thyroxine as a Mediator of Metamorphosis of Atlantic Halibut, Hippoglossus Hippoglossus

The response of morphological, histological and endocrinological development to exogenous 1-thyroxine (T4) and to water depth during metamorphosis in Atlantic halibut, Hippoglossus hippoglossus, was investigated. Exogenous T4 was given in daily doses of 0.1, 0.05 ppm or a control treatment to halibut larvae at 550 daydegrees (posthatch, premetamorphic) for 14 days. Water depths of 40 cm, 10 cm or 1.5 cm were used to rear halibut larvae from 590 daydegrees for 21 days. Halibut larvae given exogenous T4 at 0.1 ppm had accelerated eye migration relative to MH in fish given 0.05 ppm and in control fish. Pigmentation was correlated with dosage after 14 days. The volume of thyroid tissue was expressed in a dose-dependent manner and exhibited a size-dependency within each treatment. However, the follicles were atypical with reduced colloid, increased lumen and low epithelial cells even in the control group. The results indicate that T4 is a mediator in halibut metamorphosis. In the water depth experiment, only cortisol levels of larvae reared in 1.5 cm water were significantly affected after 21 days, but this was not correlated with metamorphic rate. Hormone profiles, morphological changes and size suggest the existence of a ‘window of opportunity’ for metamorphosis in halibut extending from about 16 mm and tapering off about 21 mm SL. The pooled hormone profiles indicate the commencement of a hormonal cascade similar to that of other flatfishes during metamorphosis. The results indicate that growth, neural and skeletal transformation, and pigmentation are biochemically separate processes in the metamorphosis of Atlantic halibut.

Distribution of C cells in the thyroid gland with pyriform sinus fistula

A pyriform sinus fistula can cause acute thyroiditis or recurrent infection in the neck. This fistula is believed to be a remnant of the branchial apparatus, although its origin has yet to be pinpointed. The spatial distribution of C cells in the thyroid gland was mapped by immunohistologic method in four patients with a pyriform sinus fistula. The C cells were identified immunohistologically with anticalcitonin antibody. The stained calcitonin-positive cells also crossreacted with the antibodies to carcinoembryonic antigen, chromogranin A, and neuron-specific enolase. The C cells were mainly distributed near the end of the fistula, and in three patients their concentration per unit volume of thyroid tissue was found to be inversely proportional to the distance from the end of the fistulas. Comparison of distant locations of the left-sided thyroid lobe in patients and the same region in control subjects showed a similar number of C cells. Thus this limited distribution of C cells suggested that the pyriform sinus fistula was either a remnant of the ultimobranchial body, the result of disturbed migration of the C cell in the fetus, or both.

Distribution of C cells in the thyroid gland with pyriform sinus fistula

A pyriform sinus fistula can cause acute thyroiditis or recurrent infection in the neck. This fistula is believed to be a remnant of the branchial apparatus, although its origin has yet to be pinpointed. The spatial distribution of C cells in the thyroid gland was mapped by immunohistologic method in four patients with a pyriform sinus fistula. The C cells were identified immunohistologically with anticalcitonin antibody. The stained calcitonin-positive cells also crossreacted with the antibodies to carcinoembryonic antigen, chromogranin A, and neuron-specific enolase. The C cells were mainly distributed near the end of the fistula, and in three patients their concentration per unit volume of thyroid tissue was found to be inversely proportional to the distance from the end of the fistulas. Comparison of distant locations of the left-sided thyroid lobe in patients and the same region in control subjects showed a similar number of C cells. Thus this limited distribution of C cells suggested that the pyriform sinus fistula was either a remnant of the ultimobranchial body, the result of disturbed migration of the C cell in the fetus, or both. (OTOLARYNGOL HEAD NECK SURG 1995;112:268-73.)

Measurement of radiation dose to the thyroid using positron emission tomography.

Measurements of the functioning volume of thyroid tissue have been made in 22 patients undergoing radioiodine therapy for thyrotoxicosis, using a prototype multiwire proportional counter positron camera. Tomographic images were produced of the distribution of 124I in the thyroid. Functioning volumes were found to be in the range 21-79 cm3 with volume errors of the order of +/- 4% to +/- 14%. Radioiodine uptake varied from 28% to 98%. Using a value of 6 days for the effective half-life of radioiodine in hyperactive thyroids, radiation doses from a standard therapy administration of 75 MBq of 131I varied from 11 to 48 Gy (compared with a recommended 50-70 Gy). In five cases PET imaging showed a non-uniform distribution of radioiodine in thyroids thought to have uniform uptake from conventional pinhole scintigraphy.

Single photon emission computed tomographic imaging and volume estimation of the thyroid using fan-beam geometry.

The diagnosis of thyroid disease is usually determined from planar gamma-camera images of the distribution of 99Tcm pertechnetate using a pinhole or parallel-hole collimator. The high magnification possible for a small organ imaged with a pinhole collimator means that high spatial resolution is obtainable. However, the three-dimensional spatial distribution of cold or hot regions within the thyroid is difficult to determine. Pinhole camera images give only a qualitative indication of the functioning volume of thyroid tissue, a parameter vital for the accurate dosimetry of radioiodine therapy. Clinical examination can give only a poor estimate of anatomical volume which may relate only indirectly to the volume containing radioactivity. Hamburger and Hamburger (1985) have noted that dosimetry is often largely empirical due to the difficulty of estimating the mass of thyroid tissue irradiated. The limitations of planar scintigraphy can be Overcome by performing tomographic imaging. It has already been shown ...