Tc-99m Pertechnetate Imaging Research Articles

Evaluation of the effect of isotretinoin on salivary gland function by Tc-99m pertechnetate imaging in acne vulgaris patients.

Isotretinoin is an effective drug utilized in the management of acne vulgaris and is known to cause dry mouth. In this study, we aimed to evaluate this effect of isotretinoin on the salivary gland function in patients with acne vulgaris using technetium-99m (Tc-99m) pertechnetate imaging of the salivary glands. The study population consisted of 28 patients with acne vulgaris (6 males and 22 females, mean age 20.2 ± 2.3 years), who were treated with isotretinoin for 6 months. We performed radionuclide imaging of the salivary glands pretreatment and at months 3 and 6 of treatment. After 185 MBq (5 mCi) of Tc-99m pertechnetate was intravenously administered, imaging of the salivary glands was performed over a 25-min period. We measured the following glandular function parameters for the parotid and submandibular salivary glands via time-activity curves: uptake ratio, maximum accumulation, and ejection fraction. Statistically significant differences were observed in the values obtained at months 3 and 6 of treatment, compared with the pretreatment values. This study demonstrated that radionuclide imaging of the salivary glands can clearly show the glandular functions that are affected by drugs such as isotretinoin.

Comparison of Tc-99m pertechnetate images with dual-phase Tc 99m MIBI and SPECT images in primary hyperparathyroidism.

Background:The purpose of this study was to evaluate the value of Tc-99m pertechnetate planar, dual-phase MIBI and MIBI-SPECT images in the determination and localization of parathyroid lesions.Materials and Methods:In this study, 38 patients who underwent operation for primary hyperparathyroidism were included. Tc-99m pertechnetate planar-pinhole imaging of the neck and then MIBI planar and SPECT images in supine position was performed. Late SPECT images were acquired 120 minutes after the injection. Early and late MIBI images were quantitatively evaluated.Results:Of the 38 patients, 30 of them had adenoma, 2 patients had hyperplasia and 6 of them were normal on planar images. Thirty-four of 38 patients were positive on SPECT images. SPECT images of the patients with positive results were matched with pathology results.Conclusion:As a result, Tc-99m pertechnetate planar-pinhole, Tc-99m MIBI planar and SPECT images are useful for localization of parathyroid lesions especially in multinodular thyroid gland. However, US or CT images are necessary for more accurate localization and Tc-99m pertechnetate images are useful for interpreting and comparing with the early and late MIBI images.

Tc-99m sestamibi parathyroid gland scintigraphy: added value of Tc-99m pertechnetate thyroid imaging for increasing interpretation confidence and avoiding additional testing

PurposeTo evaluate the benefit of adding a pertechnetate parathyroid scan (dual-isotope imaging) in the interpretation of sestamibi dual-phase parathyroid scintigraphy. Material and methodsOne hundred and sixteen dual Tc-99m sestamibi (MIBI) and Tc-99m pertechnetate subtraction parathyroid studies, performed between January 2000 and February 2006, were retrospectively reviewed. Dual-phase technetium sestamibi examinations were initially interpreted, with blinding to the technetium pertechnetate findings. Subsequently, technetium pertechnetate scan findings were added, and changes in interpretation were recorded. ResultsBy adding Tc-99m pertechnetate imaging, the interpretation of 17 scans (17/116=14.6%) was substantially altered. This included 5 scans (4%) that changed from negative to positive and 9 scans (8%) that changed from equivocal to positive, excluding ectopic tissue and directing minimally invasive surgery, without the need for further imaging, such as ultrasound, in 12% of cases. One examination changed from positive to negative. In addition, 2 scans changed from equivocal to negative, necessitating further preoperative imaging for the evaluation of additional pathology such as thyroid nodules and lymph nodes and the consideration of hyperplasia. Among the remaining 99 patients, Tc-99m pertechnetate scans may also have contributed to the diagnosis in the 66 positive Tc-99m MIBI scans by increasing confidence in the interpretation and obviating additional imaging. Ten cases remained equivocal. ConclusionBy adding Tc-99m pertechnetate imaging, scan interpretation was changed in 14.6% of cases, and interpretation confidence was enhanced in all but 10 remaining equivocal cases. The addition of a dual-isotope subtraction also eliminated the need for additional testing, such as ultrasound, in 12% of our cases. Increased confidence in interpretation that comes with dual-isotope subtraction may come at the cost of slight lengthening of imaging time but likely simplifies preoperative localization and decreases intraoperative time for many patients with primary hyperparathyroidism.

Imaging Identifies Submandibular Ectopic Thyroid Tissue

The identification of submandibular ectopic normal thyroid in the lateral neck with a coexisting normally located and functional thyroid gland is rare. Ectopic normal thyroid tissue in the midline location is most commonly related to aberrant migration along the thyroglossal duct (ie, lingual thyroid). A 54-year-old man with a 6-month history of visible asymptomatic swelling in the right submandibular region had ultrasonography and Tc-99m pertechnetate imaging.

Accumulations in the Salivary Gland Due to Tc-99m Pertechnetate Imaging Improved after Isotope Therapy for Graves' Disease

Accumulations in the Salivary Gland Due to Tc-99m Pertechnetate Imaging Improved after Isotope Therapy for Graves' Disease

Dramatic Movement of a Meckel's Diverticulum on Tc-99m Pertechnetate Imaging

Tc-99m pertechnetate scintigraphy is a standard procedure for diagnosis of Meckel's diverticulum. It usually presents as a static abnormality in the midabdomen. We report a 17-year-old patient with severe lower gasterointestinal bleeding and anemia. On Tc-99m pertechnetate scintigraphy, focal abnormal activity was noted in the abdomen which was moving in the abdominal cavity. The patient underwent laparatomy, and a Meckel's diverticulum was removed. The patient recovered fully after operation. © 2007 Lippincott Williams & Wilkins, Inc.

Primary Intrathoracic Goiter on Scintigraphy

A 69-year-old woman with a history of goiter and thyrotoxicosis over the previous year was seen for radioiodine therapy. At the time of a previous ablation with I-131, a thyroid scan was performed after administration of Tc-99m sodium pertechnetate. Scintigraphy showed an enlarged thyroid gland with increased thyroid uptake in the neck at its normal location along with mediastinal uptake. Contrast enhanced computed tomography (CT) showed an anterior mediastinal mass. This mass was excised. Histologic study demonstrated an ectopic primary intrathoracic nodular goiter at the site of increased activity seen on Tc-99m pertechnetate imaging.

Delayed Tc-99m Sestamibi Washout in Graves’ Disease

Tc-99m sestamibi has overtaken TI-201 as the preferred radiopharmaceutical to localize parathyroid adenomas. The differences in kinetics of sestamibi in the thyroid and parathyroid glands have resulted in the development of a two-phase imaging technique performed after a single injection of the tracer. Unfortunately, false-positive results occur in patients with thyroid nodules, although the addition of Tc-99m pertechnetate imaging to the protocol helps to differentiate between the two. Cases of concomitant primary hyperparathyroidism and Graves' disease are well documented, but there is little information about the handling of sestamibi in the latter condition. A 64-year-old woman with a history of Graves' disease and hyperparathyroidism was referred to the nuclear medicine department for a Tc-99m sestamibi parathyroid scintigram for preoperative localization of an adenoma. Early and delayed images showed diffuse delay in tracer washout in both lobes of the thyroid. A Tc-99m pertechnetate study performed 2 days later showed uniformly increased uptake consistent with Graves' disease. This case shows a hitherto unreported finding of sestamibi retention in Graves' disease. As with thyroid and parathyroid nodules, the mitochondrial content and p-glycoprotein expression may be factors responsible for this finding.

Parathyroid imaging with technetium-99m sestamibi

The accurate identification of the location of hyperfunctioning parathyroid nodules is essential to the effective surgical treatment of hyperparathyroidism. Radionuclide imaging has played an important role in the detection of pathological parathyroid nodules. Sestamibi is a new radiopharmaceutical with a good affinity for parathyroid tissue that images hyperfunctioning parathyroid lesions as hot nodules. The double-phase protocol with early (ten minutes) and delayed (120 minutes) imaging is effective fordetecting the parathyroid lesions. The use of a pinhole collimator improves the sensitivity, but attention should be paid to the ectopic gland. Most lesions heavier than 250 mg could be detected with this scintigraphy, but the detectability of hyperplastic glands is inferior to that of adenomas. A sestamibi scan is better for the detection of ectopic lesions and recurrent disease than ultrasonography, and its detectability is also superior to other radionuclide tests such as tetrofosimin scanning and the subtraction technique using thallium-201 and Tc-99m pertechnetate images. The application of sestamibi to radionuclide-guided parathyroidectomy has been studied with encouraging results. Sestamibi can also be used for the evaluation of autotransplanted glands.

The usefulness of Tc-99m pertechnetate imaging with vitamin C stimulation in Warthin's tumor.

A 67-year-old man was evaluated for swelling of the left parotid region. Diffuse accumulation of Tc-99m pertechnetate in the left parotid gland was seen on initial salivary gland imaging. However, focal high uptake was clearly delineated after 200 mg vitamin C (ascorbic acid) stimulation subsequent to the prestimulated image. This patient was pathologically confirmed to have Warthin's tumor (papillary cystadenoma lymphomatosum). It has been reported that elevated uptake of Tc-99m pertechnetate in the Warthin's tumor is seen because this tumor does not communicate with the ductal system. Therefore, Vitamin C stimulated imaging may provide a useful method for differentiating Warthin's tumor from other parotid tumors and parotitis.

Scrotal cellulitis simulating testicular infarction by Tc-99m pertechnetate imaging.

A 37-year-old man with an extensive psychiatric history attempted self-castration by tightening a coat hanger around his scrotum. This action resulted in scrotal cellulitis. Scrotal imaging with Tc-99m pertechnetate was requested to assess testicular viability. The study shows increased activity surrounding the region of the coat hanger and extending inferiorly; activity was greater on the right side. An ovoid area of relatively decreased activity on the left was interpreted initially as left testicular infarction. Subsequent surgical exploration showed that both testicles were perfused normally. The relatively decreased activity on the left presumably represents an area of less severe cellulitus.

Thyroid lymphoma and Hashimoto's thyroiditis: Tc-99m pertechnetate and Ga-67 citrate imaging in two cases.

Two women who had known Hashimoto's thyroiditis developed large neck masses, which proved to be primary thyroid lymphomas. The occurrence of thyroid lymphomas with a background of automimmune disease was noted, as well as the possible origin of these tumors from mucosa associated lymphoid tissue. The thyroid lymphomas presented as cold defects on Tc-99m pertechnetate imaging and as areas of increased uptake on Ga-67 citrate scans.

The usefulness and limitations of combined Tc-99m pertechnetate and Ga-67 citrate imaging of salivary gland disorders.

The usefulness of combined Tc-99m and Ga-67 scans in diagnosing salivary gland disorders was evaluated in a total of 31 patients. Out of 6 patients with Warthin's tumor, 4 showed a typical pattern of high-activity in the gland with retention of Tc-99m, but without an affinity for Ga-67. Out of 9 patients with pleomorphic adenoma, 8 showed a "cold" area in the tumor by Tc-99m and 5 of the 9 patients had accumulated Ga-67. Five of 6 patients with malignant tumor showed an affinity for Ga-67. Nine of 10 patients with sialadenitis showed diffuse uptake of both Tc-99m and Ga-67 in the involved gland. Combined Tc-99m and Ga-67 imaging was useful in detecting the cases of Warthin's tumor and sialadenitis (90% sensitivity and 89% specificity for sialadenitis), but the study had limitations in differentiating malignant tumors from benign tumors (66% sensitivity and 84% specificity). However, Ga-67 imaging showed a 91% negative predictive value. A negative scan could almost rule out the possibility of malignant disease of the salivary gland.

Localization of Tc-99m Pertechnetate in Lymph Node Metastasis From Occult Thyroid Carcinoma

A 30-year-old woman had two lymph node masses in the left side of neck. The thyroid gland was found to be normal on physical examination. Tc-99m pertechnetate imaging showed normal uniform activity in the thyroid, whereas tracer was seen localized in one of the two cervical lymph node masses. The possibility of skin contamination was excluded by careful examination. Fine needle aspiration cytology from the lymph node suggested a metastatic deposit from papillary carcinoma of the thyroid. Total thyroidectomy with dissection of the left cervical nodes was performed. The thyroid gland was normal in gross appearance, but histologically proved to be papillary carcinoma. Also, metastatic deposits were confirmed in the excised lymph nodes

Gastric Pull-Through Imitating Substernal Goiter

A 39-year-old man presented with a substernal mass of possible thyroidal cause. A Tc-99m sodium pertechnetate thyroid scan suggested functional substernal thyroid tissue. An 1-123 thyroid scan demonstrated a normal thyroid. The pertechnetate accumulation was assumed to be uptake in a gastric pull-through previously performed for esophageal carcinoma. The disparity between Tc-99m pertechnetate and I-123 images suggested the nonthyroidal cause of this finding. This case emphasizes the need to image mediastinal lesions that accumulate pertechnetate with a later radioiodine study

Technetium-99m Pertechnetate and Gallium-67 Imaging in Salivary Gland Disease

Thirty-two patients with salivary gland tumors or sialadenitis were studied with Tc-99m pertechnetate and Ga-67 imaging and, in some instances, sialography. The diagnostic algorithm presented allows the correct categorization of the salivary gland pathology in the vast majority of patients. The patients were studied serially with Tc-99m pertechnetate, Ga-67 and in certain situations sialography (or CT-sialography). Use of the algorithm can distinguish benign salivary tumors from malignant tumors and malignant tumors from inflammatory disease. The limitations and pitfalls of interpretation are discussed.

Diagnosis of Small Bowel Bleeding due to Ectopic Gastric Mucosa Ulcerations

Bleeding form the small intestine is of rare occurrence, but it represents a challenging problem because of the difficulties in detection and localization of the source of the hemorrhage. We used Tc-99m pertechnetate imaging in 34 patients with suspected bleeding from the small bowel. The results have proven the validity of these methods for the diagnosis of bleeding, especially in cases of ectopic gastric mucosa. Because of noninvasivity and good results, the Tc-99m pertechnetate scanning is a reasonable primary investigation in such cases.

Nuclear medicine and esophageal surgery.

The principal radionuclide procedures involved in the evaluation of esophageal disorders that are amenable to surgery are illustrated and briefly described. The role of the radionuclide esophagogram (RE) in the diagnosis and management of achalasia, oculopharyngeal muscular dystrophy and its complications, tracheoesophageal fistulae, pharyngeal and esophageal diverticulae, gastric transposition, and fundoplication is discussed. Detection of columnar-lined esophagus by Tc-99m pertechnetate imaging and of esophageal carcinoma by Ga-67 citrate and Tc-99m glucoheptonate studies also is presented.