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Failure to detect extramedullary hematopoiesis during bone-marrow imaging with indium-111 or technetium-99m sulfur colloid.

A patient with postpolycythemic myeloid metaplasia developed an enlarging abdominal mass documented on TCT scanning. To distinguish between lymphoma and extramedullary hematopoiesis, marrow elements were imaged with indium-111 chloride and technetium-99m sulfur colloid. Because the mass failed to accumulate either tracer, a presumptive diagnosis of lymphoma was made and exploratory surgery was performed. The excised mass was found to consist of enlarged lymph nodes containing extramedullary hematopoiesis. Caution should be exercised in the use of In-111 or Tc-99m SC bone-marrow scans to diagnose sites of extramedullary hematopoiesis.

Bone Marrow↗

Simultaneous display of gated technetium-99m stannous pyrophosphate and gated blood-pool scintigrams.

We have developed a method by which any two sets of R-wave-synchronized radionuclide images may be registered, color-coded, and displayed in cinematic fashion so that the image sets are superimposed and shown simultaneously in contrasting colors. The technique has been applied to technetium-99m stannous pyrophosphate (Tc-99m PPi) and equilibrium blood-pool images. Gated Tc-99m PPi and gated blood-pool image sets (16 frames per cardiac cycle) were acquired in identical projections. Image sets were then registered, if necessary, and color-coded by a computer algorithm. Our initial experience suggests that this overlay technique may be of value to: (a) detect right ventricular infarction with greater precision; (b) provide a better estimate of anatomic location and circumferential extent of Tc-99m PPi myocardial uptake relative to the ventricular blood pool; and (c) distinguish between segmental contraction abnormalities caused by recent infarction (identified by abnormal Tc-99m PPi uptake) and segmental contraction abnormalities caused by ischemia or previous myocardial infarction.

Adult↗

Scintigraphic detection of intrapulmonary bleeding using technetium-99m sulfur colloid: concise communication.

Radionuclide imaging has been successfully used clinically to determine sites of gastrointestinal hemorrhage, but its use in hemoptysis has not been studied. A dog model of intrapulmonary hemorrhage was devised. Utilizing technetium sulfur colloid, at doses of 4 and 15 mCi, bleeding rates of 0.1--0.2 cc/min were detected. In some dogs, however, significantly higher bleeding into a large bronchus, which causes a diffuse distribution of the radionuclide.

Animals↗

Technetium-99m antimony colloid for bone-marrow imaging.

Technetium-99m antimony colloid was prepared in our laboratory for bone-marrow imaging. Optimal production of colloid particles of size range 1-13 nm was achieved by the use of polyvinylpyrrolidone of mol. wt. 44,000. Electron microscopy was used to size the particles. Studies in rabbits showed exclusive concentration in the subendothelial dendritic phagocytes of the bone marrow. Pseudopods from these cells were found to traverse interendothelial junctions and concentrate colloid from the sinusoids. Imaging studies of bone marrow in rabbits showed the superiority of the Tc-99m antimony colloid over the much larger colloidal particles of Tc-99m sulfur colloid. Tissue distribution studies in the rat confirmed that bone-marrow uptake of Tc-99m antimony colloid was greater than that of Tc-99m sulfur colloid, although blood clearance was much slower.

Animals↗

Prediction of postoperative decompensated liver function by technetium-99m galactosyl-human serum albumin liver scintigraphy in patients with hepatocellular carcinoma complicating chronic liver disease.

BACKGROUND: Preoperative technetium-99m galactosyl-human serum albumin (Tc-GSA) liver scintigraphy may predict postoperative decompensated liver function and its value has been investigated in patients having resection of hepatocellular carcinoma (HCC). METHODS: Hepatic uptake ratio of Tc-GSA (LHL15) was measured before operation in 30 patients. Postoperative complications were analysed retrospectively and compared with LHL15 values and other indicators evaluating hepatic function. RESULTS: The LHL15 of 22 patients without complications was 0.91 or more, compared with 0.90 or less in the eight patients who had complications. Multifactorial analyses showed that LHL15 and Child-Pugh grade significantly predicted postoperative complications (P < 0.0001 and P = 0.0111 respectively). LHL15 was a significant predictor of complications in patients with Child-Pugh grade B disease (n = 15, P = 0.0011). CONCLUSION: LHL15 was a reliable preoperative indicator of the risk of major postoperative complications in patients who had resection for HCC.

Aged↗

Pentavalent technetium-99m-dimercaptosuccinic acid scintigraphy in renal osteodystrophy.

Pentavalent 99mTc-dimercaptosuccinic acid (DMSA) scintigraphy and 99mTc-hydroxymethylene diphosphonate (HMDP) bone scan were performed in one patient with renal osteodystrophy (ROD) before and after vitamin D3 pulse therapy. The bone scan showed diffusely increased tracer uptake in the whole skeleton, and no change of tracer distribution was noted before or after vitamin D3 pulse therapy. However, 99mTc(V)-DMSA scintigraphy revealed diffusely increased tracer uptake in the whole skeleton before therapy, and markedly decreased tracer uptake in the bones was seen at 5 mo after therapy. Increased uptake of 99mTc(V)-DMSA was observed at 7 mo after therapy, which reflected the laboratory findings. Technetium-99m-(V)-DMSA scintigraphy appeared to be more sensitive than the conventional 99mTc-HMDP bone scan in assessing the characteristics and therapeutic effect of bone disease in ROD.

Adult↗

Increased technetium-99m-GSA uptake per hepatocyte in rats with administration of dimethylnitrosamine or hepatocyte growth factor.

UNLABELLED: Technetium-99m-diethylenetriaminepentaacetic acid-galactosyl-human serum albumin (GSA) is a new scintigraphic agent that binds specifically to asialoglycoprotein receptors on hepatocytes, and can be used to evaluate hepatic function. Asialoglycoprotein receptor is a hepatocellular membrane receptor responsible for the endocytosis of asialoglycoproteins, and the function of this receptor is affected in various disease states. The aim of this study was to investigate GSA uptake per hepatocyte in the convalescent stage from hepatic damage. METHODS: We used rats with dimethylnitrosamine (DMN)-induced hepatic injury and rats with recombinant human hepatocyte growth factor (rhHGF) stimulation. Plasma clearance of GSA and the number of hepatocytes in whole liver were calculated. RESULTS: In the DMN-treated rats, the total number of hepatocytes and GSA plasma clearance were reduced significantly at 3 wk after the final administration of DMN. However, calculated GSA uptake per individual hepatocyte was significantly greater by 53.2% than in the normal controls. The area of hepatic nucleus was also significantly greater than in the normal controls. In the rhHGF-treated rats, an increase in the total number of hepatocytes was not demonstrated on the final day of rhHGF administration (Day 4). However, calculated GSA uptake per hepatocyte was significantly greater (59%) than in the controls. CONCLUSION: Augmented GSA uptake per hepatocyte during the convalescent stage after hepatic injury suggests a cellular compensation to the decreased number of hepatocyte. This mechanism may be caused by the secretion of some hepatotropic factors such as HGF.

Alkylating Agents↗

Technetium-99m HM-PAO single photon emission computed tomography imaging in transient global amnesia.

Five right-handed patients with pure transient global amnesia were evaluated with technetium-99m hexamethylpropyleneamine oxime single photon emission computed tomography after the amnesic attack. Independent of the interval between the procedure and the amnesic episode, single photon emission computed tomography demonstrated a decreased cerebral blood flow in the left temporal lobe in one patient and in the left parietotemporal region in three patients, with a more marked reduction in the temporal lobe. The remaining three patients were normal. A control single photon emission computed tomographic study was carried out in one patient 3 months after the amnesic attack and showed a left-sided persistent temporal hypoperfusion. These findings suggest that in some patients, transient global amnesia can be due to a vascular mechanism requiring strong investigations for vascular risk factors and appropriate treatment. During a follow-up period of 12 to 32 months, none of the patients with regional hypoperfusion suffered cerebrovascular events, suggesting that single photon emission computed tomography has no predictive value for further stroke.

Aged↗

Anatomic correlates of memory from intracarotid amobarbital injections with technetium Tc 99m hexamethylpropyleneamine oxime SPECT.

OBJECTIVE: To better identify regions of the brain affected by intracarotid amobarbital injections and to more precisely predict whether resections of specific brain regions will cause postoperative memory deficits. DESIGN: We modified the standard intracarotid amobarbital procedure by adding a radioactive tracer to the amobarbital injection, thereby providing better correlation between behavior and deactivated brain region. SETTING: Tertiary-care hospital center with a dedicated program for medical and surgical treatment of epilepsy. PATIENTS: We studied 39 patients with medically intractable epilepsy drawn from a regional referral base. INTERVENTION: Intracarotid injection of 125 mg of sodium amobarbital with 37 MBq of technetium Tc 99m hexamethylpropyleneamine oxime (HMPAO), followed by language and memory testing. MAIN OUTCOME MEASURES: The distribution of amobarbital as measured by single photon emission computed tomographic imaging of HMPAO and patient performance on memory tasks. RESULTS: Medial temporal regions were irrigated by the amobarbital in only 28% of the injections. Overall, findings suggest that medial temporal and lateral neotemporal cortex play a role in memory. CONCLUSIONS: The regions involved in memory function vary by individual, as does the distribution of amobarbital. Thus, the most accurate method of determining correlation of brain region with memory function during intracarotid amobarbital injection involves the use of a tracer such as HMPAO.

Adolescent↗

Relationship of technetium Tc 99m sestamibi scans to histopathological features of hyperfunctioning parathyroid tissue.

OBJECTIVE: To investigate the histopathological features of pathologic parathyroid specimens associated with negative preoperative technetium Tc 99m sestamibi scans. DESIGN: Retrospective study. SETTING: Tertiary care center. PATIENTS: One hundred fourteen patients who underwent sestamibi scans before surgical exploration for primary hyperparathyroidism between 1996 and 2001. INTERVENTIONS: Surgical exploration and removal of parathyroid adenomas. MAIN OUTCOME MEASURES: Histopathological characteristics associated with true-positive and false-negative sestamibi scans, including parathyroid specimen weight, size, relative oxyphil and chief cell content, parathyroid hormone staining patterns, cellular architecture, and various immunohistochemical staining patterns. RESULTS: Twenty-three (24%) of 98 patients with parathyroid adenomas had negative sestamibi scan results. Among 20 age- and sex-matched patients with false-negative results vs 20 patients with true-positive results, tumor size (P = .04) and oxyphil cell content (P = .03) were found to be significantly different. CONCLUSION: Parathyroid gland size and oxyphil content are descriptive and predict differences between sestamibi properties of parathyroid adenomas but have no current therapeutic implications for parathyroid surgery.

Adenoma↗

The pitfalls of technetium Tc 99m/thallium 201 parathyroid scanning.

Technetium Tc 99m/thallium 201 parathyroid scanning has been proved to be effective by multiple researchers. A review of 54 patients who underwent scanning and operations at an institution showed the scans to be accurate in 83%. There were 15% false-negative and 2% false-positive scans. The pitfalls of parathyroid scanning can be related to false-positives and false-negatives.

Adenoma↗

Postoperative technetium scanning in patients with submandibular duct diversion.

Submandibular duct diversion is a common procedure for refractory sialorrhea in children. The procedure reroutes Wharton's ducts from the floor of the mouth to the tongue base. As the majority of saliva in the resting state is produced by the submandibular glands, rerouting markedly decreases sialorrhea. However, the procedure has been criticized in that diversion may cause fibrosis and stricture of the ducts. The gland would atrophy, and the physiologic functions of saliva would be lost. Glandular function of six patients with cerebral palsy (mean age, 14.7 years) was evaluated by technetium scanning (mean time after surgery, 43 months). Four patients had normal bilateral function; two patients had no function in one gland but normal function in the contralateral gland. We conclude that bilateral submandibular duct diversion maintains long-term function in at least one gland.

Adolescent↗

Regional xenon 133 cerebral blood flow and cerebral technetium 99m HMPAO uptake in unmedicated patients with obsessive-compulsive disorder and matched normal control subjects. Determination by high-resolution single-photon emission computed tomography.

We measured regional cerebral blood flow (rCBF) with the xenon 133 (133Xe) inhalation method and with regional cerebral uptake of technetium 99m d,l-hexamethyl propyleneamine oxime (99mTc-HMPAO) by single-photon emission computed tomography in 10 adult male patients with obsessive-compulsive disorder (OCD) and in 10 age-matched adult male normal controls. With the 133Xe method, there were no significant differences in cortical or basal ganglia blood flow between the patients with OCD and their matched controls. In the patients, there was a positive relationship between rCBF and the severity of both obsessive and compulsive symptoms (average r = .48). These rCBF findings were consistent with those of earlier reports of increased rCBF in patients with OCD who were undergoing imaginal flooding and who had exacerbation of symptoms following m-CPP administration. 99mTc-HMPAO is a lipophilic molecule that crosses the blood-brain barrier and is converted to a hydrophilic form that is trapped in the brain. The amount that is trapped is determined primarily by blood flow, but also by membrane permeability and kinetics of conversion of the 99mTc-HMPAO to the hydrophilic form. Compared with their matched controls, the patients with OCD had significantly increased 99mTc-HMPAO uptake in the high dorsal parietal cortex bilaterally, in the left posterofrontal cortex, and in the orbital frontal cortex bilaterally. Possible explanations include (1) increased rCBF that was not detected with 133Xe, (2) increased permeability of the blood-brain barrier and/or cell membranes, and (3) increased conversion and trapping of the lipophilic, injected form of 99mTc-HMPAO in these regions.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

Parathyroid localization with high-resolution ultrasound and technetium Tc 99m sestamibi.

HYPOTHESIS: High-resolution ultrasound and technetium Tc 99m sestamibi scanning can be used for preoperative localization of abnormal parathyroid glands in patients with hyperparathyroidism. DESIGN: Ultrasound and sestamibi scanning were performed in patients undergoing neck exploration for hyperparathyroidism. If the 2 scans agreed in identifying a single adenoma, and surgery confirmed the location of a single adenoma and an ipsilateral normal gland, a unilateral exploration was performed. SETTING: University tertiary care center. PATIENTS: Sixty-one consecutive patients undergoing surgery for hyperparathyroidism from September 1, 1994, through September 30, 1997. INTERVENTIONS: High-resolution ultrasound was performed in 59 patients and sestamibi scanning in 58 patients; all patients underwent neck exploration by a single surgeon. MAIN OUTCOME MEASURES: The results of preoperative ultrasound and sestamibi scanning were compared with operative and histological findings. RESULTS: All patients were cured of hypercalcemia. Specificity of ultrasound and sestamibi scanning was 98% and 99%, respectively; however, their sensitivity was only 57% and 54%, respectively. Both imaging modalities had lower sensitivities in the setting of multigland disease. If both imaging studies were considered as a single test, sensitivity for imaging in patients with primary hyperparathyroidism reached 78%. Our localization protocol allowed a unilateral approach in 43% of patients (23 of 53). CONCLUSIONS: These results confirm the value of preoperative localization in patients with hyperparathyroidism. A unilateral approach can be used with a high degree of success in cases when ultrasound and sestamibi scanning agree in the identification of a single adenoma confirmed by surgical exploration with the identification of a normal ipsilateral gland.

Adenoma↗

Unilateral surgery for primary hyperparathyroidism on the basis of technetium Tc 99m sestamibi and iodine 123 subtraction scanning.

HYPOTHESIS: Parathyroid scanning, based on simultaneous recording of technetium Tc 99m sestamibi and iodine 123 images, is able to identify patients with multiple parathyroid gland disease and is a safe imaging technique for unilateral parathyroid surgery. DESIGN: Scintigraphic criteria of eligibility for unilateral surgery were prospectively tested against findings of conventional bilateral surgery. SETTING: Patients referred to an endocrine surgeon in a university hospital. PATIENTS: Seventy consecutive patients with primary hyperparathyroidism had dual-isotope scanning before conventional surgery. Forty-one patients had scan findings compatible with unilateral surgery, with a single focus of high intensity seen on the anterior and lateral views. The remaining 29 patients had 1 or more criteria of ineligibility: (1) scan findings pointing to multiple gland disease, (2) no well-identified focus, (3) contralateral thyroid nodule requiring surgical management, or (4) family history of hyperparathyroidism or multiple endocrine disease. MAIN OUTCOME MEASURES: Number of enlarged parathyroid glands at surgical inspection and calcemia follow-up. RESULTS: None of the 41 patients, with a single well-defined focus on the scan image, showed evidence of multiple parathyroid involvement. Each parathyroid adenoma was resected from the precise site predicted by the subtraction scan. Nine patients (13%) had surgical findings of multiple parathyroid gland disease. All 9 were ineligible based on preoperative image findings. CONCLUSIONS: Unilateral surgery can be safely offered to 60% of patients with primary hyperparathyroidism, on the basis of simultaneous (99m)Tc-sestamibi and (123)I scanning. This may reduce the length of the operation, anesthesia requirements, and hospital stay, and the risks of hypoparathyroidism and injury to the recurrent laryngeal nerve.

Adult↗

Relative contributions of technetium Tc 99m sestamibi scintigraphy, intraoperative gamma probe detection, and the rapid parathyroid hormone assay to the surgical management of hyperparathyroidism.

HYPOTHESIS: Technetium Tc 99m sestamibi scintigraphy, intraoperative gamma probe detection, and the rapid parathyroid hormone assay have been used to permit a directed operation in patients with hyperparathyroidism. We hypothesized that the coordinated use of these techniques might be particularly useful in patients who require a second operation for hyperparathyroidism. DESIGN: Retrospective analysis was performed to determine the specific contribution of these technologies to the surgical management of patients with hyperparathyroidism who underwent evaluation by at least 2 of these techniques between April 1996 and October 1999. SETTING: Patients were evaluated and treated by an endocrine tumor surgery group within a tertiary care referral center. PATIENTS: Coordinated application of 99mTc-sestamibi scintigraphy, intraoperative gamma probe detection, and/or the rapid parathyroid hormone assay was performed in 32 patients. RESULTS: Twenty-eight of 32 patients had primary hyperparathyroidism, 3 had multiple endocrine neoplasia type 1, and 1 had secondary hyperparathyroidism. The surgical procedure was an initial cervical exploration in 19 and a second operative procedure in 13. Parathyroidectomy was successful in all patients. A directed anatomic operation was performed in 24 patients, including 11 patients who underwent second operative procedures and 9 patients who underwent minimally invasive procedures under local anesthesia. A directed operation was facilitated by sestamibi scan in 22 of 24 patients, intraoperative gamma probe detection in 5 of 23 patients, and the rapid parathyroid hormone assay in 15 of 15 patients. CONCLUSIONS: Coordinated application of 99mTc-sestamibi scintigraphy, intraoperative gamma probe detection, and the rapid parathyroid hormone assay allows for successful directed reoperative parathyroidectomy; a minimally invasive procedure may be performed in selected patients.

Adenoma↗

Localization of lower gastrointestinal hemorrhage. Experience with red blood cells labeled in vitro with technetium Tc 99m.

Seventy-six patients clinically suspected of having lower gastrointestinal bleeding were studied by scintigraphy utilizing red blood cells labeled in vitro with technetium Tc 99m. Sixteen patients required emergency surgery; bleeding was accurately localized in 15 (94%). One patient (6%) had a normal scan. A 20-month mean follow-up of the 16 patients showed no recurrent bleeding. Of 60 patients not requiring emergency surgery, bleeding was localized in 11, but the bleeding ceased. Forty-nine of the 60 patients had normal scans and had no further hemorrhaging during hospitalization. A 21-month mean follow-up of 38 of the 49 patients showed no further bleeding episodes or surgical procedures in 29 patients; however, eight patients required surgical procedures, including seven for gastrointestinal malignancies. Scanning of red blood cells labeled in vitro with 99mTc is accurate and efficacious in localization of bleeding sites that require emergency surgery for lower gastrointestinal hemorrhage.

Adult↗