摘要:

PurposeIt has been reported that the effect of radioactive iodine (RAI) treatment is complete in 4 to 6 months. This retrospective study evaluated the appropriate time for repeated treatment of hyperthyroid disease with RAI after initial treatment failure.MethodsOutcomes of 128 patients treated with RAI for hyperthyroid disease were reviewed retrospectively at 3 and 6 months.ResultsEighty patients (group A) were treated successfully with a single dose of RAI. Twenty patients (group B) required a second treatment dose. Twenty-eight patients were lost to follow-up. All patients in group A were clinically improved to various degrees at 3 months and continued to improve at 6 months. All eight patients in group B who showed no improvement at 3 months remained the same at 6 months. The difference between the two groups was statistically significant.ConclusionPatients with hyperthyroid disease who are unimproved at 3 months can be retreated with RAI without further delay.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

PurposeIodine-123 is a pure gamma emitter and has excellent characteristics for imaging with modern scintillation cameras. The goal of this study was to compare the performance of I-123 and I-131 as imaging agents for whole-body scanning in patients with differentiated thyroid cancer undergoing ablation for thyroid remnants after initial surgery.MethodsFourteen patients with differentiated thyroid cancer who had undergone near-total thyroidectomy and had serum thyroid-stimulating hormone levels greater than 40 mU/l underwent diagnostic scanning 5 hours after administration of 48 to 56 MBq (1.3 to 1.5 mCi) I-123 and 48 hours after administration of 111 MBq (3 mCi) I-131. After receiving ablative I-131 therapy, they also underwent whole-body planar imaging 7 days later. The diagnostic I-123 and I-131 scans were compared with each other and with the post-therapy images by two nuclear medicine physicians and one endocrinologist.ResultsThe diagnostic scans revealed 35 foci in the thyroid bed and neck. The I-123 images showed all 35 foci, but only 32 of the 35 foci (91%) were seen on the I-131 scans. The findings of pre- and post-therapy scans were concordant in 11 of 13 patients, and the same general sites of uptake (left and right thyroid bed, midline) were revealed on both sets of images. In one patient, a focus seen on the diagnostic I-123 and I-131 images was not visualized on the post-therapy scan and was thought to represent possible stunning. An additional area of uptake in the lower right neck and upper mediastinum was present on the post-therapy scan of another patient, but it was not seen on diagnostic images.ConclusionThese results show improved quality of imaging with 50 MBq (1.5 mCi) I-123 compared with 111 MBq (3 mCi) I-131 for whole-body scanning in patients with differentiated thyroid cancer undergoing thyroid remnant ablation. I-123 imaging may prove to be the preferred procedure in such settings in patients with differentiated thyroid cancer.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

In Tc-99m MIBI scintimammography, the exact localization of foci of increased tracer uptake or the exact anatomic correlation of palpated breast masses with a scintigraphic finding is difficult. The authors describe three patients with known or possible malignant breast lesions for whom the use of external radioactive markers successfully helped to provide this information, thus improving the diagnostic accuracy and guiding decision-making in the patients’ treatment.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

PurposeTechnetium-99m–labeled sulfur colloid lymphoscintigraphy is useful to evaluate lower extremity lymphatic circulation in cases of possible lymphedema and to reveal abnormal lymphatic collections. Groin lymphatic fistulas and lymphoceles are known complications of peripheral vascular surgical procedures. The authors describe a patient with ascites that developed into right lower extremity swelling after surgical repair of a femoral artery injury. Even after surgical ligation of multiple lymphatic channels, the patient continued to have lymphorrhea. It was unclear whether this was attributable to a persistent lymphatic leak or an ascitic leak from a postsurgical defect resulting in an abnormal connection with the peritoneal cavity.MethodsLymphoscintigraphy of the lower extremities was performed using Tc-99m sulfur colloid. Images were obtained at several intervals after injection of the radiotracer. Images were also acquired after the wound packing was removed.ResultsThe images revealed an accumulation of radiotracer in the right groin, confirming the lower extremity lymphatic origin of the collection.ConclusionsLymphoscintigraphy is useful to evaluate the origin of serous collections in the groin, a region in which lymphatic complications of vascular surgery are not uncommon.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Cardiac function is commonly evaluated in patients with cancer in most nuclear medicine departments. At their dedicated cancer facility, the authors routinely perform a dynamic right anterior oblique first-pass study and a 4-minute left anterior oblique static planar study in addition to the routine equilibrium gated scanning in appropriate projections. Here they show the range of noncardiac disease encountered using this protocol. Useful unexpected information can be obtained from left ventricular ejection studies, and further data may be gained from these simple additions to this common test.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

The use of Tc-99m sestamibi to localize parathyroid adenomas is well established. Its greatest value is in the detection of adenomas in presurgical candidates to localize one or more adenomas in the parathyroid glands or to identify ectopic parathyroid adenomas. The authors describe a patient who had long-standing hyperparathyroidism with a history of end-stage renal disease, hypertension, and peptic ulcers with gastrointestinal bleeding. The scan showed a large ectopic parathyroid adenoma in the left retrosternocleidomastoid region. At surgery, the adenoma was located between the jugular vein and the carotid artery, within the carotid sheath.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Ga-67 scintigraphy is helpful in the assessment of active extrapulmonary sarcoidosis. Muscular involvement of sarcoidosis is often asymptomatic or nonspecific, and laboratory examinations do not provide convincing evidence of muscular involvement. The authors report a case of muscular sarcoidosis detected by Ga-67 scintigraphy. In a patient who had fever and arthralgia of both knee joints, Ga-67 scintigraphy showed mediastinal and hilar involvement of sarcoidosis with unexpected extensive muscular uptake. Magnetic resonance imaging revealed in detail intramuscular infiltration of sarcoid granuloma. Ga-67 scintigraphy is useful in detecting inflammatory muscular involvement of sarcoidosis and other multiorgan involvement.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Technetium-99m red blood cell (RBC) scintigraphy is a very specific method to differentiate a hemangioma from other hepatic masses. The authors report a case of hepatocellular carcinoma that showed a focal area of increased uptake on Tc-99m RBC SPECT in a 60-year-old man. Dynamic computed tomography and angiography revealed features of both hemangioma and hepatocellular carcinoma. Pathologic examination showed that the portion of the hepatocellular carcinoma that showed increased uptake on Tc-99m RBC scintigraphy had peliosis, which is the likely cause of the radiotracer avidity.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

PurposeHypoxic–ischemic injury induces early changes in cerebral energy that later lead to the presence and extension of brain damage and subsequently to severe neurodevelopmental impairments such as the dyskinetic form of cerebral palsy, which is associated with damage to the striatum. The purpose of the current study was to evaluate the viability of D2 receptors in the perinatal period using I-123 iodobenzamide brain SPECT and to correlate this with early neurologic status.MethodsAfter obtaining informed parental consent, 12 full-term neonates with hypoxic–ischemic events were included. I-123 iodobenzamide brain SPECT was performed 1 week after birth, corresponding to a gestational age of 39.2 ± 1.7 weeks. Images were acquired using a brain-dedicated gamma camera 1 hour after intravenous injection of 30 MBq (0.8 mCi) I-123 iodobenzamide. Magnetic resonance images (T2 weighted sequence: repetition time/echo time: 2,000/30 to 150) of the brains of the same neonates were acquired on the same day.ResultsThe right and left striatum:cerebellum activity ratios were between 1.28 and 2.25, with the greatest concentration of I-123 iodobenzamide occurring in the striatum area. A tendency of the striatum:cerebellum ratio to decrease was observed as the severity of the perinatal hypoxic–ischemic event increased despite striatal hypersignal on magnetic resonance imaging in only two neonates.ConclusionsThis study, which confirms that I-123 iodobenzamide could be used in the neonatal period, shows the biochemical maturation of D2 receptors as early as 1 week after birth and also suggests the deleterious effect of perinatal hypoxic–ischemic events on D2 receptors.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

BackgroundPositron emission tomography (PET) metabolic studies have investigated the pathways involved in fatty acid, glucose, and oxidative metabolism in cardiomyopathy and the impairments that occur in the damaged myocardium, but none have provided absolute quantitative variables. Recently, quantitative measurements of the metabolic rate of oxygen (MMRO2) and oxygen extraction fraction (OEF) using O2-15–labeled oxygen gas have been validated in animals and healthy volunteers. The purposes of the current study were to measure MMRO2and OEF in cardiomyopathy with left ventricular (LV) dysfunction.MethodsThe authors selected 25 study participants: 16 patients (10 with ischemic and 6 with dilated) cardiomyopathy with LV dysfunction, and 9 healthy volunteers. As evaluated by echocardiography, LV ejection fraction (LVEF) was decreased in patients (35% ± 9% vs. 65% ± 5%,P< 0.01). The PET protocol consisted of transmission, C O2-15 static, H2O-15 dynamic, and O2-15 gas inhalation steady state scans. An entire myocardial region of interest was drawn to encompass the entire LV myocardium on three midventricular slices in each participant.ResultsData showed in patients with dilated cardiomyopathy significant reductions of MMRO2(0.051 ± 0.02 ml · min−1· g−1vs. 0.108 ± 0.02 ml · min−1· g−1,P= 0.01) and OEF (0.55 ± 0.15 vs. 0.71 ± 0.08,P= 0.01) when compared with healthy volunteers. Furthermore, OEF decreased significantly in lateral and inferior walls. Significant correlations were observed among OEF and the rate-pressure product (RPP) (P= 0.02), LVEF (P< 0.001), MMRO2 and RPP (P= 0.04), and LVEF (P= 0.05). In patients with ischemic cardiomyopathy, MMRO2was significantly reduced (0.039 ± 0.02 ml · min−1· g−1vs. 0.108 ± 0.02 ml · min−1· g−1;P= 0.005) but not OEF (0.63 ± 0.2 vs 0.71 ± 0.08;P= NS), when compared with healthy volunteers. Significant correlations were observed among OEF and RPP (P= 0.03), LVEF (P= 0.002), MMRO2and RPP (P< 0.01), and LVEF (P= 0.03).ConclusionsThese data show that O2-15 gas inhalation and PET allow myocardial MMRO2and OEF to be measured in patients with cardiomyopathy.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID