Lateral cervical ectopic thyroid gland (LETG) is rare and often difficult to distinguish from metastatic lymphadenopathy; furthermore, no standardized surgical strategy is available. This study aims to clarify the clinical features of and establish an optimized management framework for this anomaly. We present one benign LETG case and one malignant LETG case and performed a systematic literature review (2000-2025), yielding a pooled analysis of 69 cases. The analysis revealed that a definitive pre- or intra-operative diagnosis was pivotal. Malignant pathology in both the lateral neck lesion and the orthotopic thyroid gland predicted multiple surgeries (41.7%, p = 0.007; 39%, p = 0.038). Crucially, the utilization of intraoperative frozen sections was decisive, as all patients who underwent this approach avoided a second operation. LETG management necessitates a systematic approach. Our proposed "Seven-Step Diagnostic Algorithm" and "Dual-Axis Treatment Strategy" facilitate precise differentiation, enable a definitive single-stage surgery, minimize reoperations, and guide selective preservation of the orthotopic thyroid.

In vertebrates, the thyroid gland synthesizes hormones that act on almost all tissues and are essential for normal growth and metabolism. Thyroid hormone production relies on iodination of thyroglobulin and requires H2O2, which contributes to a relatively high basal oxidative stress in the thyroid that must be tightly controlled to prevent cellular damage. The thyroid has efficient antioxidant and detoxifying enzymes that help it resist H2O2-induced oxidative stress maintaining the homeostasis necessary for hormone synthesis. By regulating the expression of genes involved in cellular detoxification, NRF2 acts as a master regulator of the cellular defense against oxidative stress. Using zebrafish embryos and mouse ESC-derived thyroid organoids, we generated nrf2a/Nrf2 loss-of-function and identified a common dyshormonogenesis phenotype. Although in zebrafish, the driving mechanisms are possibly related to thyroglobulin iodination defects, in thyroid organoids, it is likely due to a reduction in Tg production, consequently affecting folliculogenesis and thyroid hormone production.

The thyroid, ultimobranchial, and adrenal glands are major endocrine organs in birds, essential for regulating various physiological functions. This study presents a comprehensive morphological and ultrastructural investigation of these three glands in adult male Egyptian turkeys using light microscopy, and transmission electron microscopy (TEM). The thyroid and ultimobranchial glands are in the thoracic cavity near the trachea, while the adrenal glands are positioned adjacent to the caudal vena cava and cranial poles of the kidneys. Histologically, the thyroid follicles are lined by simple cuboidal to columnar epithelium. The ultimobranchial gland appears as a single-lobed structure encased in a thick capsule and composed of C-cell follicles and cords. These C cells exhibit light and dark variants, with ultrastructural evidence of secretory granules, abundant vacuoles, and active rough endoplasmic reticulum. The adrenal gland is encapsulated by a thick layer of connective tissue. Its parenchyma showed intermingled interrenal and chromaffin cells, with the former arranged in multilayered follicles. Chromaffin cells formed large clusters and are distinguished into epinephrine and norepinephrine types by ultrastructure and Grimelius silver staining. These findings contribute valuable insights into the comparative avian endocrinology and structural adaptations of the turkey's endocrine organs.

The thyroid gland is a highly vascularized organ in vertebrates. However, the information on the vascular pattern of this gland in pigs remains limited. This study elucidates the morphoanatomy and arterial supply of the gland in three breeds: Landrace (L), Large White (W), and Crossbreed (LWD). Two hundred twelve pigs were used and dissected to observe the arteries supplying blood to the gland. As a result, the gland was classified into three types based on its appearance: pear-shaped, butterfly-shaped, or partially separated. Moreover, the arteries supplying the gland were observed and then compared among breeds. The arterial supply of the thyroid gland on the cranial side consisted of branches from the cranial laryngeal artery, cranial thyroid artery, superficial cervical artery, and common carotid artery. Otherwise, the caudal side was supplied by the caudal thyroid artery, superficial cervical artery, bicarotid trunk, internal thoracic artery, and external thoracic artery. Furthermore, significant differences were identified between L and LWD, as well as between W and LWD, in the pattern of arterial origin on the cranial right side of the thyroid gland. Similarly, on the left side, significant differences were observed not only between L and W but also between W and LWD. On the caudal side, significant differences were found between L and W, as well as between W and LWD. These anatomical variations provide important insights for research and clinical applications involving the thyroid gland in pigs.

Objective.Accurate target localization in frameless stereotactic radiosurgery (SRS) is commonly achieved using intrafraction kV x-ray imaging, which contributes to patient imaging dose. In this study, the feasibility of reducing the imaging dose in CyberKnifeTMSRS by implementing copper (Cu) beam-hardening filtration while preserving image-guided targeting accuracy is investigated.Approach.Entrance skin dose (ESD) at isocenter was measured for standard aluminum (Al) filtration and additional Cu filtration thicknesses of 0.12 mm and 0.24 mm. Monte Carlo simulations were used to characterize Cu-induced x-ray spectral changes and to estimate imaging doses using patient-specific voxelized anatomical models over a range of tube potentials and filtration conditions. The effect of Cu filtration on targeting accuracy was assessed using end-to-end (E2E) tests, supplemented by patient image data.Main results.Copper filtration progressively removed low-energy photons, increasing the mean photon energy from 56 keV with standard Al filtration to 60 keV and 64 keV for 0.1 mm and 0.2 mm Cu filtration at 120 kVp. At 10 mAs, ESD increased from 0.248 mGy at 80 kVp to 0.822 mGy at 150 kVp with Al filtration, while addition of 0.12 mm and 0.24 mm Cu reduced ESD by 46% and 64% at 80 kVp and by 25% and 36% at 150 kVp, respectively. Patient model calculations confirmed meaningful organ dose sparing for the eye lenses, thyroid gland, and skin. For 6Dskull tracking, implementation of Cu filters induced modest image brightness/gradient error changes which were readily compensated by small kVp increase without mAs adjustment. For Xsight spine and fiducial tracking algorithms registration performance was maintained with the addition of Cu filtration. E2E testing confirmed that the total system targeting error was maintained for all three tracking algorithms studied.Significance.Copper filtered imaging constitutes an effective strategy for optimizing imaging dose in the evaluated CyberKnife tracking workflows without compromising tracking accuracy.

Radiotherapy (RT) is used quite often among breast cancer patients, and because these patients now live longer than they used to, long-term treatment-related adverse effects, such as hypothyroidism, are becoming increasingly relevant. Radiation-induced hypothyroidism is a late side effect of radiation to the thyroid gland, which could develop months to years after radiotherapy. However, there are insufficient data on hypothyroidism in patients with breast cancer who receive locoregional RT, which usually affects a portion of the thyroid gland. In this prospective study, we aimed to evaluate the association between radiation dose to the thyroid gland and early thyroid dysfunction in breast cancer patients treated with hypofractionated locoregional radiotherapy, and to establish potential planning objectives that could help in sparing the thyroid gland. Our study included 109 women who received 3-D conformal locoregional breast radiotherapy. These patients had normal thyroid function prior to start of radiotherapy. Patients had follow-up thyroid function tests 6 months after finishing radiotherapy. Based on dose volume histograms (DVH), the percentages of the thyroid volume, and ipsilateral thyroid lobe, receiving 5, 10, 15, 20, 25, 30, 35, and 40 Gy (V5, V10, V15, V20, V25, V30, V35, and V40 respectively), in addition to the mean and maximum thyroid doses, were estimated. Follow-up assessment of thyroid function and statistical analysis unveiled incidence of radiotherapy induced hypothyroidism to be 8.3%. Possible risk factors included high maximum radiation dose and V40 to the thyroid gland and the ipsilateral thyroid lobe, as well as high mean dose and smaller volume of the ipsilateral thyroid lobe. The likelihood of hypothyroidism was significantly increased with V40 of >5% of the thyroid gland, and V40 of >11% of the ipsilateral thyroid lobe. Further study is recommended for larger populations and longer follow-up periods.

Hypercalcemic crisis from a functioning parathyroid adenoma (PA) is exceptionally rare in prepubertal children and typically presents with a non-specific complaint such as polyuria or lethargy. We report a 7-year-old girl who was urgently referred for acute, colicky abdominal pain and repeated vomiting, which clinically mimicked acute appendicitis. During the work-up, extensive metabolic tests incidentally revealed severe hypercalcemia and elevated intact parathyroid hormone (PTH), which led to the diagnosis of PA-induced hypercalcemic crisis.Her initial manifestation was an acute abdomen rather than renal or neuropsychiatric symptoms. The case underscores that functioning PA should be included in the differential diagnosis of children presenting with unexplained gastrointestinal distress, and illustrates that timely diagnosis and focused parathyroidectomy can effectively reverse biochemical abnormalities, alleviate skeletal symptoms, and mitigate the risk of serious long-term complications. We report the case of a seven-year-old female patient who was hospitalized due to complaints of abdominal discomfort accompanied by episodes of recurrent vomiting.Subsequent analysis revealed that these symptoms may represent acute gastrointestinal syndrome in the context of a hypercalcemic crisis.We describe her clinical course, diagnostic workup, and treatment. Laboratory tests revealed severe hypercalcemia (4.67 mmol/L; reference range: 2.1-2.7mmol/L), along with hypophosphatemia, hypomagnesemia, and markedly elevated PTH (268.1 pg/mL).Thyroid ultrasound revealed a nodule in the inferior aspect of the right lobe of the thyroid gland, which was subsequently confirmed by contrast-enhanced CT.After urgent management of hypercalcemia-including intravenous fluids, furosemide, salmon calcitonin, and pamidronate-the patient underwent surgical excision of the right inferior parathyroid gland.Histopathological examination confirmed the diagnosis of a benign PA. Serum calcium and PTH levels normalized within 24 hours postoperatively, with complete resolution of clinical symptoms. Marked hypocalcemia developed within several days postoperatively and was corrected. During follow-up to date, serum calcium,PTH levels, and ultrasound examination of the parathyroid have been normal. PA represents an uncommon yet manageable cause of hypercalcemic crisis in pediatric patients. Timely assessment of serum calcium and PTH levels in individuals presenting with unexplained gastrointestinal symptoms-such as nausea, vomiting, or abdominal pain-facilitates swift diagnosis, thereby reducing the need for unnecessary diagnostic procedures like extensive imaging or invasive tests.Surgical resection of the PA is the first-line treatment. Postoperatively, prevention of hungry bone syndrome and long-term follow-up are required.

Hypothyroidism is a prevalent pathological condition resulting from insufficient thyroid hormone production by the thyroid gland. The potential role of vitamin D supplementation in the prevention and treatment of various diseases is well-recognized. However, its specific impact on individuals with hypothyroidism remains unclear. This systematic review follows the PRISMA 2020 flowchart. The review aimed to evaluate the effects of vitamin D on hypothyroidism by synthesizing available evidence. A comprehensive search was conducted across several databases, including PubMed, Embase, Web of Science, and the Cochrane Library, up to February 2024. Standard mean differences (SMDs) and odds ratios (ORs) with their 95% confidence intervals (CIs) were calculated using fixed or random effects models, based on heterogeneity assessed by the I² statistic. Sensitivity analyses and assessments of publication bias were also performed. The certainty of evidence was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. A total of 5 randomized controlled trials and 11 observational studies, encompassing 4,152 subjects, met the inclusion criteria. The analysis revealed that vitamin D supplementation significantly reduced thyroid-stimulating hormone (TSH) (SMD = -1.76 mIU L- 1, 95% CI [-3.23, -0.29] mIU L- 1), and thyroid peroxidase antibody (TPO-Ab) (SMD = -113.31 U ml- 1, 95% CI [-141.42, -85.21] U ml- 1). Additionally, serum vitamin D deficiency was significantly associated with the prevalence of hypothyroidism (OR = 4.06, 95% CI [1.96, 8.39]). The results indicate that patients with hypothyroidism are more likely to have low serum vitamin D levels compared to healthy individuals. Moreover, vitamin D supplementation significantly reduced TSH and TPO-Ab levels. It is recommended that patients with hypothyroidism have serum vitamin D levels routinely monitored in clinical practice.

Congenital hypothyroidism (CH) may result from a developmental or functional defect of the thyroid gland (primary CH), or to hypothalamic-pituitary axis dysfunction (central CH), or more rarely from abnormalities in the action, transport, or metabolism of thyroid hormones. In the absence of prompt initiation of replacement therapy during the neonatal period, CH can lead to profound impairment in growth and neuropsychomotor development. Since signs of CH early in life can be subtle and difficult to recognize, early detection and prompt treatment goals have been achieved by newborn screening (NBS), which was started fifty years ago. A narrative review was conducted to identify studies describing how the evolution of NBS for CH has contributed to improve diagnostic accuracy and outcomes of affected children. From its start, the main objective of NBS for CH has been the eradication of intellectual disability resulting from severe CH. However, over decades it has become clear that CH covers a spectrum of phenotypes, including mild, moderate, and severe forms of hypothyroidism. In addition, numerous outcome studies have confirmed that early CH detection by NBS followed by timely replacement therapy effectively prevents brain damage, underscoring the success and importance of this screening program. The improvement of NBS and advances in the management of CH have dramatically enhanced patient outcomes through increasingly personalized care from birth to adulthood. Although overall outcomes are generally favorable, ongoing monitoring of treatment adequacy and patient adherence remains essential.

Subclinical hypothyroidism (SH) in childhood is frequently idiopathic and usually follows a benign course. Heterozygous loss-of-function variants in the thyrotropin receptor (TSHR) gene have emerged as a genetic cause of isolated hyperthyrotropinemia; however, data regarding long-term outcomes and management are limited. We retrospectively evaluated 51 children (aged 1-18 years) diagnosed with idiopathic SH followed for a mean of 4.9 ± 2.6 years. TSHR gene analysis was performed using targeted next-generation sequencing in patients selected based on neonatal TSH elevation, family history of SH, thyroid gland in situ, or persistence of SH after levothyroxine withdrawal. Clinical, biochemical, ultrasonographic, and treatment outcomes were compared between patients with and without TSHR variants. Heterozygous TSHR variants were identified in 18 patients (35.2%), including one novel missense variant. Variant-positive patients generally showed a stable, compensated thyroid phenotype without progression to overt hypothyroidism. Levothyroxine therapy was discontinued in 6 of 11 initially treated patients after genetic diagnosis, with sustained biochemical stability. However, five patients required re-initiation of therapy due to rising TSH levels (15.7-27.8 mIU/L) or clinical symptoms. Lower thyroid volume SDS and the presence of additional clinical risk factors, such as small-for-gestational-age birth or developmental delay, were associated with treatment requirement. No patient developed overt hypothyroidism. Heterozygous TSHR variants appear to contribute to the pathogenesis of pediatric idiopathic SH and are frequently associated with a stable, compensated thyroid phenotype. These findings support a conservative, individualized management strategy rather than routine levothyroxine therapy.

Supraclavicular fossa (SCF) irradiation is integral to adjuvant radiotherapy (RT) for node-positive breast cancer. Due to anatomical proximity, the thyroid gland is frequently exposed, leading to hypothyroidism in approximately 20-40% of long-term survivors. Despite robust dose-response evidence, thyroid management remains inconsistent and breast cancer-specific dose guidance is lacking. This nationwide survey evaluated current practice patterns regarding thyroid delineation, SCF contouring, and thyroid dose guidance during elective SCF irradiation in Switzerland. Astructured electronic questionnaire was distributed between May and November 2025 to all 30 Swiss radiation oncology centers treating breast cancer. Institutional characteristics, thyroid contouring practices, SCF target delineation, and applied thyroid dose guidance were assessed. Analyses were descriptive only. Thirty-three responses from 25 of 30centers (83%), including all university hospitals, were analyzed. Modern RT techniques were widely implemented (VMAT 79%, IMRT 15%). Routine thyroid contouring was reported by 91% of respondents, of which 94% used AI-assisted tools. However, only 55% applied explicit thyroid dose guidance. Reported mean thyroid dose (Dmean) thresholds ranged from 12to 35 Gy and clustered at 13.5-15 Gy, 20-21 Gy, and 30-32 Gy. Excluding ALARA ("as low as reasonably achievable") responses, the median Dmean guidance was 21 Gy (IQR 16-30 Gy). SCF delineation varied substantially, particularly regarding superior and medial margins, and 64% reported CTV/PTV cropping to reduce thyroid dose. Despite strong dose-response evidence and widespread availability of advanced RT techniques, thyroid protection during elective SCF irradiation remains inconsistently implemented. These findings reveal agap between evidence and practice and support the development of harmonized, breast cancer-specific recommendations, including routine thyroid delineation, anatomy-based SCF contouring, and explicit, oncologically safe dose guidance-particularly Dmean targets of ≤ 13.5 Gy, with ≤20-21 Gy as apragmatic upper limit-to reduce radiation-induced hypothyroidism without compromising cancer control.

Radioiodine-131 (131I) is the most significant environmental contaminant during a short-term nuclear accident. When present in the atmosphere, it concentrates mainly in the thyroid gland through inhalation or ingestion. This can lead to partial or total destruction of thyroid cells, potentially causing hypothyroidism. It therefore negatively affects the thyroid in exposed populations. At high doses, radiation can also cause cellular mutations and increase the risk of thyroid cancer, particularly in children under five years old and those exposed during pregnancy. In such cases, nonradioactive iodine tablets are used to saturate the thyroid and block the absorption of radioactive iodine. This study aimed to quantify and compare total atmospheric emissions of 131I using the ORIGEN-JR code, and to assess the radiological impacts on the environment and humans by estimating and comparing the total effective dose (TED) and committed effective dose equivalent (CEDE) using the HOTSPOT code in the early stages following the Fukushima accident and at the TRIGA Mark-II research reactor in Bangladesh. The simulation results indicate that for the TRIGA MARK-II research reactor, the TED was approximately 379mSv at a distance of 360m, with a thyroid CEDE of 19mSv. For the Fukushima reactor, the TED was approximately 875mSv at 590m, with a thyroid CEDE of about 63mSv. Compared to the IAEA's annual regulatory limits, the TED and CEDE resulting from the Fukushima accident exceeded the permissible thresholds, requiring both evacuation of the population and iodine prophylaxis. Conversely, for the TRIGA MARK-II research reactor, the distribution of iodine tablets is not necessary; however, containment measures remain essential.

The aberrant right subclavian artery (ARSA) is the most common anomaly of the arch of aorta and is significantly associated with a non-recurrent laryngeal nerve (NRLN). Nevertheless, the co-occurrence of ARSA with complex thoracic wall vascular remodeling is scarcely described in the current literature. This exploration describes an unusual group of neurovascular variations with important surgical significance. A precise dissection was performed on a 43-year-old female donor of Thai descent embalmed with soft-embalming technique with vascular silicone-color injection. The cervical and upper thoracic regions were dissected with emphasis on neurovascular pattern, and morphometric measurements. A retroesophageal ARSA was found to be the fourth branch of the aortic arch after the left subclavian artery, without a Kommerell diverticulum. A right-sided NRLN was confirmed to arise directly from the vagus nerve to then travel upwards next to the larynx. Crucially, the right internal thoracic artery (ITA) was completely absent, and its usual vascular territory was replaced by the superior intercostal artery (SIA) arising from the inferior aspect of the ARSA. Moreover, a separate muscular branch of the proximal ARSA was observed to provide blood supply to the left longus colli muscle. The current report describes a novel association of ARSA, NRLN, complete absence of the right ITA with a compensatory SIA and a muscular branch from the ARSA to the left longus colli muscle. This research emphasizes the embryological connection of the development of the cervical and thoracic vessels and indicates that thorough preoperative imaging is required to prevent any iatrogenic injury during surgery of the thyroid gland, cervical spine, esophagus and coronary bypass surgeries.

Maternal consumption of khat has been associated with adverse neonatal outcomes like preterm birth and low birth weight. These effects resemble those seen in neonatal hypothyroidism, suggesting that khat disrupts thyroid function in the fetus. There is, however, limited data on the microscopic alterations in the thyroid gland of offspring following maternal consumption of khat. We examined the same in rat offspring whose mothers were exposed to khat during pregnancy as the suitable animal model. Female rats were acquired and randomized into groups receiving khat extract (200 or 500 mg/kg) or distilled water. Maternal khat consumption was started 7 days before mating and continued throughout pregnancy. From the offspring born, 28 thyroid glands were harvested and processed for histological analysis with hematoxylin and eosin and Ki-67 staining. Data on the follicle density and diameter, follicular cell epithelia, follicular cell nuclear-cytoplasmic index, and expression of proliferation marker Ki-67 were collected. These were analyzed using SPSS and key findings presented in tables and photomicrographs. Compared to controls, khat-treated groups exhibited parenchymal disruption evidenced by a dose-dependent epithelial shift of follicular cells from columnar to cuboidal, reduced follicular diameter, reduced follicular density, and increased nuclear-cytoplasmic index. There was also suppressed proliferative activity evidenced by a reduction in cells expressing Ki-67. Infiltration of follicular cells into colloid was observed in treated groups. The observed parenchymal insult of the fetal thyroid gland following maternal exposure to khat could partially explain the adverse birth outcomes seen in the offspring.

Development and internal validation of the thyroid-weight-adjusted neck compression score (NCS) using postmortem serum free triiodothyronine.

Microplastics (MPs) have been identified in multiple human tissues and are increasingly implicated in systemic health risks. Their presence in the thyroid gland, however, remains unexamined. Autoimmune thyroiditis (AIT) is the most frequent autoimmune thyroid disorder and the leading cause of hypothyroidism. This study aims to detect the presence of MPs in the thyroid and their potential relevance to AIT. In this case-control study, thyroid tissues were obtained from 29 patients with histologically confirmed AIT and 29 age- and sex-matched non-AIT controls who underwent thyroidectomy due to thyroid nodules. MP burden was quantified by pyrolysis-gas chromatography-mass spectrometry (Py-GC/MS). Particle-level polymer identity and particle characteristics, including size, shape, and color, were assessed using micro-Raman spectroscopy, whereas scanning electron microscopy (SEM) was employed for morphological observation. MPs were detected in thyroid tissues from both groups. Py-GC/MS revealed significantly higher total MP concentrations in the AIT group compared to controls (median: 19.9 vs. 1.9 μg/g; p=0.012). This elevation was primarily driven by polyvinyl chloride (PVC), which was significantly higher in AIT patients. Micro-Raman spectroscopy identified particles ranging from 33.9 to 1467 µm. The AIT group contained significantly increased MPs abundance compared with the non-AIT control group (172 vs. 50.2 items/g, p=0.037). Morphological profiling revealed no significant differences in the size, shape and color of MPs between groups. An increased MPs burden with the particular enrichment of PVC was observed in patients with AIT, suggesting a potential association between environmental MPs exposure and thyroid autoimmunity. Further mechanistic and epidemiological studies to clarify the impacts of chronic MPs exposure are needed.

Liquid-Based Cytologic Features of a Thyroid TFE3-Rearranged PEComa-Like Neoplasm: A Case Report.

Metastasis of fallopian tube carcinoma to the thyroid gland: A case report

The isthmus connects the two lateral lobes of the thyroid gland. It remains unclear whether nodules in the isthmus signify a higher risk of thyroid malignancy. We searched PubMed, Scopus, and the Web of Science Core Collection through June 2025 for English literature containing sufficient information to analyze the risk of malignancy for thyroid nodules in different locations. Non-English studies, pediatric populations, research focused on small subsets with specific characteristics, and animal or tissue studies were excluded. Random-effects meta-analyses were conducted to estimate the pooled odds ratios (OR), and the JBI Critical Appraisal Checklist was used for quality assessment. The study was registered with PROSPERO (CRD420251103875). We included 27 studies with 33,474 patients. The median age was 49 years, and 78% were female. Isthmus nodules were associated with higher odds of thyroid cancer (OR 1.46; 95% confidence interval [CI] 1.08 to 1.98). To address moderate heterogeneity, a sensitivity analysis excluding studies with a potentially high risk of bias revealed a consistent trend with a pooled OR of 1.90 (95% CI, 1.38 to 2.60). This meta-analysis demonstrates an increased risk of malignancy for thyroid nodules in the isthmus compared to those in the lobes. Although the findings suggest a potential benefit of lowering the biopsy threshold for isthmus nodules, this should be interpreted with caution due to the observational design and possible biases.

To assess changes in thyroid hormone levels following radioactive iodine (RAI) therapy, evaluate post-treatment clinical outcomes, and identify factors associated with thyroid status among hyperthyroid patients treated at a tertiary care hospital in Peshawar. This was a retrospective cohort study conducted at Nuclear Medicine and Endocrinology Department of Northwest General Hospital, from January 2022 to December 2024. A total of 83 adult patients with Graves' disease, toxic adenoma, or toxic multinodular goiter who received RAI therapy were included. RAI was administered using a fixed-dose protocol based on clinical diagnosis and disease severity. Antithyroid drugs were discontinued prior to RAI as per standard institutional protocol. Baseline demographic and clinical characteristics, including age, gender, and diagnosis, were recorded. Thyroid hormone levels (Free T4, T3, and TSH) were measured at baseline and six months post-treatment. Data on thyroid gland size and TRAb levels were not routinely available and therefore not included in the analysis. Only patients with complete six-month follow-up data were analyzed. Pre- and post-treatment hormone levels were compared using the Wilcoxon Signed-Rank Test, and binomial logistic regression was used to identify predictors of thyroid status. The mean age of patients was 49.76±15.2 years, predominantly female (69%). Graves' disease was the most common diagnosis (54.8%). At six months post-RAI therapy, 44.0% developed hypothyroidism, 41.7% became euthyroid, and 14.3% remained hyperthyroid. Post-treatment thyroid status was significantly associated with underlying diagnosis (p < 0.001), while no significant associations were observed with age (p=0.060) or gender (p = 0.364). Significant reductions in Free T4 (2.19 to 1.01 ng/dl) and T3 (2.01 to 1.02 ng/dl), along with an increase in TSH (0.01 to 3.65 mIU/L), were observed following RAI therapy (p<0.001). On regression analysis, Graves' disease was identified as a significant predictor of post-treatment hypothyroidism (adjusted OR=16.48, 95% CI: 3.14-86.58; p=0.001), whereas age, gender, toxic adenoma, and RAI dose were not statistically significant predictors. RAI therapy was associated with hypothyroidism as a common outcome, particularly among patients with Graves' disease, while other clinical factors showed limited association with post-treatment thyroid status.