Parathyroid imaging: comparison of 201Tl-99mTc subtraction scintigraphy, computed tomography and ultrasonography

From 1982 to 1985, twenty-nine patients with suspected hyperparathyroidism were examined using 201Tl-99mTc subtraction scintigraphy (Tl-Tc), computed tomography (CT) and ultrasonography (US). For diagnosing neoplasm (adenoma or cancer), the sensitivities of the three procedures were 80 per cent or more, with no statistically significant differences. For diagnosing hyperplasia of the parathyroid glands, CT scan had the highest sensitivity (47 per cent). The most frequent source of error was minimally enlarged glands, weighing less than 500 mg. The second highest source of error was thyroid nodules, such as adenomatous goiter or cancer. Serum calcium and c-PTH levels were significantly higher in those with a parathyroid neoplasm than in those with hyperplasia (p less than 0.01, p less than 0.05, respectively). We concluded that hyperplasia is less easy to detect than neoplasm, and CT scan is superior to Tl-Tc or US scan for localizing hyperplasia.     

Urinothorax demonstrated on 99mTc ethylene dicysteine renal scintigraphy.

Case A 35-year-old Asian male presented with complaints of fever,right-sided pleuritic chest pain and shortness of breath of7 days’ duration, 1 month after a right percutaneous nephrolithotomy(PCNL) by supracostal puncture. On examination, the patientwas pale and tachypnaeic with pulse 120/min and blood pressure150/100 mm Hg. He had stony dullness with decreased     

A prospective evaluation of preoperative localization by technetium-99m sestamibi scintigraphy and ultrasonography in primary hyperparathyroidism

BACKGROUND: Ultrasonography (USG) and technetium-99m sestamibi (MIBI) scintigraphy are commonly used imaging modalities in the era of minimally invasive parathyroidectomy (MIP) for primary hyperparathyroidism (pHPT). However, their relative importance and actual contribution to MIP have not been prospectively assessed. METHODS: A total of 100 consecutive pHPT patients planning for MIP were recruited. Both USG and MIBI findings were correlated with intraoperative findings and postoperative outcome. Clinicopathologic factors were examined for potential association with a correct localizing result. RESULTS: Thirty men and 70 women (age range 13 to 93 years [median 55.5]) were included in the study. The final pathology included 98 patients with solitary adenoma and 2 patients with multiglandular disease. The sensitivities, accuracies, and positive predicted values for USG and MIBI alone were 57% vs 89%, 56% vs 85%, and 97% vs 94%, respectively. Correctly localized adenomas were significantly heavier than incorrectly localized ones. CONCLUSIONS: MIBI is preferred over USG in pHPT patients planning for MIP. Weight of adenoma appeared to be the only clinicopathologic factor determining localization accuracy.     

Prediction of final tumor response to preoperative chemotherapy by Tc‐99m MIBI imaging at the middle of chemotherapy in malignant bone and soft tissue tumors: Comparison with Tl‐201 imaging

The aim of this study was to assess the predictive power of ^99mTc‐MIBI scintigraphy performed in the middle of chemotherapy, for the final tumor response to chemotherapy, and compare it to that of ²⁰¹Tl in malignant bone and soft tissue tumors (MBST). Sixty‐eight patients with MBST underwent ^99mTc‐MIBI and ²⁰¹Tl scintigraphies at 15 min after tracer injection before the first, and after the third, chemotherapy cycles. After five cycles of chemotherapy and tumor resection, therapeutic effect was assessed by histopathology. Less than 90% and ≥90% necrosis were judged as poor and good response to chemotherapy, respectively. Tracers uptake ratios were calculated by dividing the lesion count density by that of the background. ^99mTc‐MIBI perfusion index was also calculated. The % reduction of the perfusion index (ΔPI) and uptake ratios (ΔUR) calculated by 100 × [(prechemotherapy value ? postchemotherapy value)/prechemotherapy value] were compared with histologic response. The sensitivity, specificity, and accuracy for the prediction of effective chemotherapy in ^99mTc‐MIBI imaging were 80%, 95%, 88% in ΔUR, and 74%, 74%, 74% in ΔPI, respectively. The area under the receiver operator characteristic curve (A_z) of the ^99mTc‐MIBI‐ΔUR (0.923) was significantly higher than that of ΔPI (0.809, p = 0.025) but only marginally higher than that of the ²⁰¹Tl‐ΔUR (0.865, p = 0.079). A_z in ²⁰¹Tl (0.865) was not significantly different from that of ΔPI (0.809, p = 0.35). ^99mTc‐MIBI imaging performed in the middle of chemotherapy well predicts the final tumor response to chemotherapy in patients with malignant bone and soft tissue tumors. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 26:411–418, 2008     

Poor renal uptake of99mtechnetium-dimercaptosuccinic acid and near-normal99mtechnetium-mercaptoacetyltriglycine renogram in nephronophthisis

Four patients with the clinical diagnosis of nephronophthisis are presented, all having a very poor renal uptake of^99mtechnetium-dimercaptosuccinic acid (^99mTc-DMSA) but clearly visualized kidneys on early images with^99mtechnetium-mercaptoacetyltriglycine and a normal or almost normal renogram. There was no difference between a young patient in an early stage of the disease and the other three patients with more advanced renal disease. In contrast, a patient with tubulointerstitial nephritis with uveitis had considerably better renal uptake of^99mTc-DMSA despite impaired renal function. We suggest that the specific tubular function defect in nephronophthisis might be the cause of the poor uptake of^99mTc-DMSA. We also recommend the method to support the clinical suspicion of nephronophthisis, even in the early stages of the disease.     

Establishing a diagnosis of adrenal metastasis from hepatocellular carcinoma by 99mTc-PMT hepatobiliary scintigraphy

A 69-year-old woman was diagnosed as having hepatocellular carcinoma (HCC) with liver cirrhosis in October, 1984 and treated by transcatheter arterial embolization (TAE). In June, 1990 she was found to have a huge mass in the left hypochondrium which ultrasonography and computed tomography (CT) scan revealed to be a left adrenal mass. A ^99mTc pyridoxyl-5-methyl tryptophan (^99mTC-PMT) hepatobiliary scintigraphy was positive and confirmed metastatic HCC. Although the adrenal mass was large, the HCC itself was controlled well with TAE. The adrenal mass was removed surgically in July, 1990 and the histological findings were compatible with HCC metastasized to the adrenal gland.     

Prediction of residual total renal function before nephron-sparing surgery using99mTc-DMSA renal scintigraphy

Background Although radical nephrectomy is the standard treatment for renal cell carcinoma, nephron-sparing surgery is the preferred treatment in patients with a single functioning kidney. It is important before surgery to evaluate the level of residual renal function likely after the operation. In this study, we investigated the prediction of residual renal function, using technetium Tc 99m dimercaptosuccinic acid (^99mTc-DMSA) renal scintigraphy, before nephron-sparing surgery for renal tumors. Methods Preoperative and postoperative evaluation of renal function was done in 11 patients with renal cell carcinoma or renal angiomyolipoma, using^99mTc-DMSA scintigraphy. Nine patients had renal cell carcinoma and 2 had renal angiomyolipoma. Partial nephrectomy was performed in 4 patients and surgical enucleation in 7 patients. Both the predicted total DMSA renal uptake rate prior to surgery and the actual postoperative total^99mTc-DMSA renal uptake rate were obtained. Endogenous creatinine clearance and serum creatinine levels were also obtained. Results There was a good relationship between the predicted and postoperative total^99mTc-DMSA renal uptake rates. The ratio of the postoperative total DMSA renal uptake rate to the predicted total^99mTc-DMSA renal uptake rate was 85% after partial nephrectomy, and 101% after surgical enucleation. There was also a significant correlation between the postoperative total^99mTc-DMSA renal uptake rate and creatinine clearance, and postoperative total^99mTc-DMSA renal uptake rate levels above 11.4% coincided with serum creatinine levels below 2.0 mg/dL. Conclusion Preoperative assessment with^99mTc-DMSA renal scintigraphy is clinically useful for predicting residual renal function after nephron-sparing surgery.     

Diagnostic usefulness of201T1-chloride scintigraphy for preoperative localization of parathyroid tumors

²⁰¹T1-chloride scintigraphy was performed in 10 patients with hyperparathyroidism to assess the localization of abnormal parathyroid glands. This approach proved to be useful in 8 of 10 patients. In particular, an intramediastinal ectopic gland was clearly demonstrated in one patient. Several disadvantages were noted, however,²⁰¹Tl-chloride scintigraphy could be the first choice for preoperative localization of abnormal parathyroid glands. If a negative image is obtained, further examinations such as arteriography or parathyroid hormone assay by selective venous blood sampling should be done.     

Simultaneous measurement of extracellular fluid distribution and renal function with a single injection of 99mTc DTPA

BACKGROUND.: The initial rate of renal uptake of ^99mTc DTPA is equal to theproduct of injected dose and the glomerular filtration rate(GFR):plasma volume (PV) ratio, whilst later the plasma clearancerate constant is equal to the GFR:extracellular fluid volume(ECF) ratio. Expressing GFR in terms of body fluid volumes hasseveral attractions, and techniques for measuring it in thisform may be useful. METHODS.: GFR/PV was determined from a Patlak plot in 82 studies in 47patients undergoing routine gamma-camera ^99mTc DTPA renographyand compared with GFR/ECV, determined from the terminal slopeof the plasma clearance curve. RESULTS.: GFR/PV (y) correlated significantly with GFR/ECV (x): y= 3.2.x+5.3 ml/min/l (r=0.82, n=82, P<0.001). The ratio, GFR/PV:GFR/ECVis ECV/PV, which (x) correlated significantly with a regionalestimate (y) of ECV/PV (rECV/rPV) derived from a Patlak plotapplied to a subrenal ROI: y= 0.47x+1.14 (r=0.61, n=52, P<0.001).The initial rate constant of disappearance of ^99mTc DTPA fromthe blood, determined from a ROI over the left ventricle, reflectstracer clearance from plasma to interstitial fluid plus GFR/PV.Subtraction of GFR/PV yields a rate constant which reflectsextrarenal ^99mTc DTPA clearance, Z, as a fraction of PV. A regionalestimate of ^99mTc DTPA clearance from plasma to interstitialfluid, rZ, was derived from the Patlak plot applied to the subrenalROI and expressed in relation to rPV. Z/PV (y) correlated significantlywith rZ/rPV (x): y=2.2x+0.02 min^–1 (r=0.56, n=52, P<0.001).The distribution of ECF between plasma and interstitial fluidwas related to extrarenal ^99mTc DTPA clearance. Thus rZ/rPVcorrelated significantly with ECV/PV (r=0.55, n=52, P<0.001)and Z/PV correlated significantly with rECV/rPV (r=0.6, n=52,P<0.001). There was no correlation between renal functionand extrarenal ^99mTc DTPA clearance or distribution of ECF. CONCLUSIONS.: GFR can be measured in terms of PV and ECF volume from a singleinjection of ^99mTc DTPA. ECV/PV, rECV/rPV, and variables representingthe clearance of ^99mTc DTPA across the microvasculature canbe measured at the same time.     

Mediastinal parathyroid adenoma detected by99mTc-methoxyisobutylisonitrile: Report of a case

We report herein the case of a 30-year-old man in whom ectopic mediastinal parathyroid adenoma was detected by^19mTc-methoxyisobutylisonitrile scintigraphy (^99mTc-MIBI). The patient presented with a history of recurrent renal stones and was diagnosed as having primary hyperparathyroidism due to elevated serum levels of calcium and intact parathyroid hormone (i-PTH) levels. On admission, his serum calcium value was 12.1 mg/dl and the i-PTH level was 137 pg/ml. Ultrasonography, computed tomography (CT), and 201TlCl-^99mTcO^– ₄ subtraction scintigraphy (TI-Tc) were performed but none of these imaging techniques was able to detect an enlarged parathyroid gland. Selective venous sampling revealed that the serum i-PTH level was highest at 422pg/ml in the left brachiocephalic vein. Exploration of the neck also proved unsuccessful. Finally, we performed^99mTc-MIBI which revealed and delineated an enlarged parathyroid gland in the upper mediastinum. Tumor extirpation was subsequently performed through a left thoracotomy. Pathologically, the tumor was confirmed to be a parathyroid adenoma and the serum calcium and i-PTH levels returned to within the normal ranges postoperatively.     

A comparison between ultrasonography and mammography,computed tomography and digital subtraction angiography for the detection of breast cancers

Ultrasound (US) was compared with mammography (MMG), computed tomography (CT), and digital subtraction angiography (DSA) in its effectiveness to detect breast cancer masses and metastatic axillary nodes. Forty-seven breast cancer patients who all underwent MMG, US, CT, and DSA preoperatively in our institution between 1986 and 1990 were studied. US was able to detect tumors in all cases regardless of tumor size, whereas DSA detected T1-size tumors and MMG detected T2-size tumors in 40% and 64.7% of cases, respectively, being specifically inferior to US. It was found that MMG was least likely to detect papillotubular carcinoma, although microcalcification alone without a tumor mass on MMG improved detectability from 46.2% to 76.9%, according to the histological type. CT was found to be most sensitive to axillary node metastases (81.8%), followed by US (72.7%), but DSA was significantly unfavorable (42.9%). Thus, we concluded that US was superior to MMG, CT, and DSA for detecting breast cancer masses, but that CT was more advantageous than US, while DSA was of little value for evaluating axillary nodal status.     

Kinetics of99mTechnetium-Tin-methylene-diphosphonate in normal subjects and pathological conditions: A simple index of bone metabolism

Summary The blood clearance and the urinary excretion of the bone scanning complex technetium-tin-methylene-diphosphonate (^99mTc-Sn-MDP) administered intravenously have been measured in 27 normal subjects and 104 patients with post-menopausal osteoporosis, osteomalacia, primary hyperparathyroidism, Paget's disease, pagetoid metastases of prostatic cancer, osteolyses, chronic renal failure, and liver cirrhosis to quantitate the skeletal uptake of the radiopharmaceutical. Kinetic analysis of the data was performed in terms of a four-compartment model; correspondent rate constants and fitted values were estimated. In normal subjects the whole-body retention (WBR) up to 24 h was 33.3%±7.4 SD, whereas significantly more elevated values were observed in several pathological conditions, the highest values being ascertained in patients with pagetoid metastases, primary hyperparathyroidism, and chronic renal failure and whenever large osteoid seams were present. Differences were found between osteoporosis and osteomalacia, monostotic and polyostotic Paget's, pagetoid and osteolytic metastases of bone. In Paget's disease significant correlations have been observed between WBR and the exchangeable calcium pool, WBR and the serum alkaline phosphatase, and WBR and the urinary excretion of hydroxyproline. Kinetic analysis demonstrated that WBR provided overestimate of the skeletal retention by an average of 16%, the retention in the “extravascular space” being greater in patients with chronic renal failure. This simple method shows significant promise for a quantitative approach to the skeletal turnover in metabolic bone disease.     

Evaluation of the effect of portal vein embolization on liver function by (99m)tc-galactosyl human serum albumin scintigraphy

BACKGROUND: Preoperative percutaneous transhepatic portal vein embolization (PTPE) increases the safety of liver resection and improves the outcome after surgery for hepatocellular carcinoma. Scintigraphy with (99m)Tc-galactosyl human serum albumin (GSA) causes specific binding to viable hepatocytes and serves as an index of liver function. MATERIALS AND METHODS: (99m)Tc-GSA scintigraphy was performed before and 2 weeks after PTPE of the right portal vein in 16 patients. The total receptor index, reflecting overall liver function, right receptor index (right lobe), and left receptor index (left lobe) were calculated. RESULTS: After PTPE, the proportion of the volume of the nonembolized lobe (left lobe) increased (P = 0.0002). The total receptor index slightly decreased after PTPE (P = 0.090), the right receptor index decreased (P < 0.0001), and the left receptor index increased (P < 0.0001). The average increase rate in the left receptor index was 30% of the pre-PTPE value. In 2 patients with portal hypertension (> or =30 cm H(2)O) after PTPE, the left receptor index did not change. In 4 patients whose left receptor index after PTPE (including the 2 patients with portal hypertension) was <0.35, right lobectomy was not performed. CONCLUSIONS: (99m)Tc-GSA scintigraphy demonstrated that PTPE induces a shift in hepatic function from the embolized part to the nonembolized part of the liver. PTPE of the right portal vein increases the hepatic functional reserve of the left lobe as well as its volume. The changes in (99m)Tc-GSA uptake following PTPE may predict the response to liver resection.     

Renal function remains after unilateral total and contralateral partial nephrectomy: an experimental study in pigs using 99mTc-DTPA

Twelve nephrectomies (NEs) were performed in 12 pigs (11–17 kg). Total NE was performed on the left side and partial NE on the right side (lower third of the kidney), thus two-thirds of the total kidney volume was removed. Renal function was studied with ^99mTc-diethylenetriaminepentaacetic acid (DTPA) renography and serum urea and creatinine levels preoperatively, and 1 and 2 weeks postoperatively. The pigs were imaged in each session for 30 min by collecting 10-s frames from a posteroanterior (PA) view of an anaesthesized animal. The injected activity was 37 MBq. Serial blood samples were taken from the subclavian vein at 0, 1, 2, 3, 5, 15, 25, 40, 60 and 120 min (six animals) after ^99mTc-DTPA injection. The DTPA disappearance rate (DDR) was determined from these samples and in other cases (six animals) a blood sample at 20 min was used. The DDR was also determined from the dynamic gamma imaging data: Regions of interest (ROI) were upper body, spleen, heart and kidneys. The ROI analysis correlated well with the blood sampling data (r=0.97, P<0.0001). The reference values for pig DDRs were 0.99±0.08%/min. These values were 0.71±0.08%/min at 1 week postoperatively and 0.63±0.08%/min at 2 weeks. DTPA clearance rates were preoperatively 0.53±0.06 ml/s; at 1 week postoperatively 0.41±0.06 ml/s; and at 2 weeks 0.35±0.06 ml/s. There were no significant differences pre- and postoperatively in creatinine and urea concentrations. The DTPA clearance (ml/s) and disappearance rates (%/min) when determined per kidney area (cm²) increased significantly (P<0.001 at both 1 and 2 weeks); in 11 of 12 animals the function of the resected right kidney was higher than the split function of the whole right kidney preoperatively. Unilateral nephrectomy initiates a functional adaptation or a growth response in the contralateral kidney to compensate for the loss of a renal mass. These data also indicate that two-thirds of the kidney volume in young pigs can be removed without danger.     

Scintiscanning demonstration of thymoma: Comparative study on scintiscans using201Tl,67Ga and75Se

Thymus scintigraphy was performed using²⁰¹Tl-chloride,⁶⁷-Ga-citrate and⁷⁵Se-selenomethionine on 30 thymoma patients with or without myasthenia gravis. Mass negativity was observed in 6 out of 17 (35.3 per cent) and 3 out of 13 cases (23.1 per cent), respectively. A rate of 70 per cent (21 cases out of 30) of mass positivity was observed by thymus scan using²⁰¹Tl. With regard to the relation between thymus scan and cell type,²⁰¹Tl-scan exhibited a high rate of mass positivity, regardless of the cell type while the⁷⁵Sescan showed a trend toward mass positivity in epithelial cell predominant cases. With²⁰¹Tl, mass positivity was observed when the CPM/g ratio for tumors and blood exceeded 3.0. This trend can serve as an index for the suitability of supplementary chemo- and radiotherapies, as well as for prognosis in cases of relapse, and in those for whom excision was not complete.     

计算机断层扫描血管造影和数字减影血管造影在主动脉夹层诊断及术前评估中的应用比较

目的探讨计算机断层扫描血管造影(CTA)和数字减影血管造影(DSA)在主动脉夹层(AD)的诊断及术前评估的作用及一致性。方法回顾性分析60例AD患者的临床资料,比较CTA及DSA两种检查方法显示的AD破口近侧锚定区的距离、左锁骨下动脉左侧平面胸主动脉直径、主动脉夹层累及的范围及主动脉主要分支血管的累及情况。结果 60例患者均同期行CTA、DSA检查,CTA、DSA检查破口近端锚定区的距离大于或等于15mm者分别为44例(44/51,86.2%)、46例(46/56,82.1%);小于15mm者分别为7例(7/51,13.7%)、10例(10/56,17.8%),两种方法比较差异无统计学意义。CTA发现夹层累及左髂动脉(LIA)36例(36/60,60.0%)、累及右髂动脉(RIA)28例(28/60,46.7%),DSA仅发现夹层累及LIA14例(14/60,23.0%)、累及RIA13例(13/60,21.7%),两种方法比较差异有统计学意义(P=0.012,P=0.022);CTA、DSA在显示左锁骨下动脉左侧胸主动脉直径及内脏动脉受累情况比较差异无统计学意义。结论 CTA、DSA两种检查方法有较好的一致性,CTA因其无创性在EVAR术前评估中有重要价值。     

Diagnosing osteomyelitis in the diabetic foot: a pilot study to examine the sensitivity and specificity of Tc99mwhite blood cell‐labelled single photon emission computed tomography/computed tomography

Diabetic foot ulceration poses a significant threat of osteomyelitis (OM) and subsequent amputation. The diagnosis of OM via imaging studies is difficult as radiographic findings do not present immediately and advanced imaging studies may be contraindicated or unavailable. A novel diagnostic tool has been developed which synthesises technetium‐99 white blood cell‐labelled single‐photon emission computed tomography and computed tomography (Tc^99mWBC labelled‐SPECT/CT) imaging, effectively enhancing anatomic detail. The aim of this pilot study was to determine the validity and reliability of this novel imaging technique in patients with diabetic foot ulcers in a Veterans Affairs healthcare facility. A retrospective review was performed on consecutive patients who met the inclusion criteria (n = 14) and underwent Tc^99mWBC‐labelled SPECT/CT for suspected OM. Histopathologic analysis of bone specimen (when available) and International Working Group on the Diabetic Foot consensus criteria were used as a reference standard. The sensitivity and specificity of Tc^99mWBC‐labelled SPECT/CT were 87·50% [confidence interval (CI): 64·58–110·42%] and 71·43% (CI: 37·96–104·90%), respectively. Negative predictive value (NPV) and positive predictive value (PPV) were 83·33% (CI: 53·51–113·15%) and 77·78% (CI: 50·62–104·94%), respectively, with a likelihood ratio (LR) of 3·063 and an accuracy of 80%. These findings suggest Tc^99mWBC‐labelled SPECT/CT can be useful in imaging OM in patients with diabetic foot ulcers.     

Sentinel Lymph Node Mapping of the Colon and Stomach Using Lymphoseek in a Pig Model

Background: Lymphoseek is a radiopharmaceutical designed for sentinel lymph node (SLN) mapping. The purpose of this study was to compare Lymphoseek colon and gastric pharmacokinetics with filtered [^99mTc]sulfur colloid (fTcSC).Methods: Eight anesthetized pigs received an endoscopic injection of Lymphoseek or fTcSC in the stomach and colon. Scintigraphy was obtained of both administration sites at 15-minute intervals up to 3 hours after injection, after which all SLNs were identified by a handheld gamma probe through a laparotomy incision. Isosulfan blue was administered at the injection site 5 minutes before SLN mapping. The percentage of injected dose (%ID) was measured for all harvested nodes, and the clearance half-life (T_c) was calculated for all injection sites.Results: The mean Lymphoseek clearance for colon (T_c, 2.56 ± 1.04 hours) and gastric (T_c, 3.83 ± 1.18 hours) injection sites was statistically faster (P = .030) compared with fTcSC (colon T_c, 14.98 ± 3.41 hours; stomach T_c, 14.52 ± 4.08 hours). After 3 hours, Lymphoseek exhibited a mean SLN %ID of 1.32% ± 1.71% in the colon and 2.04% ± 2.12% in the stomach; this was not statistically different from fTcSC (colon, .63% ± .39%; stomach, 2.35% ± 2.90%). SLN uptake of Lymphoseek was significantly different from second-echelon node %ID for the colon (P = .011) and gastric (P = .029) injection sites. All SLNs exceeded 10 times background, and there was no discordance between isosulfan blue and Lymphoseek or fTcSC.Conclusions: Three hours after colon stomach administration, Lymphoseek demonstrated rapid injection site clearance, detectable SLN uptake, and low second-echelon node uptake.