Impact of radiotherapy on normal brain tissue: semi-automated quantification of decrease in perfusion.

Purpose: We attempted to ascertain the impact of Co-60 conventional external radiotherapy (cRT) on the perfusion of normal brain tissue in relation to the radiation doses delivered to the tumors in patients with primary brain tumors.

Materials And Methods: After surgery 18 patients (pts) were due to undergo cRT with a total dose of 5400- 6400 cGy. All the patients had a Tc-99m-HMPAO SPECT study prior to cRT (basal), 15th and 30th days of cRT as well as 1 (in 6 pts), 3 (in 9 pts), and 6 (in 3 pts) months after cRT.

Influence of the heterogeneity of P-glycoprotein expression on technetium-99m-MIBI uptake in breast cancer.

Unlabelled: We prospectively studied a total of 30 patients with breast cancer to evaluate the relationship between the degree of accumulation of 99mTc-sestamibi (MIBI) and the heterogeneity of p-glycoprotein expression in tumor tissues.

Methods: Twenty patients during initial presentation and 10 patients during post-therapy evaluation underwent contemporaneous 99mTc-MIBI imaging and surgery or biopsy. Immunohistochemical studies were performed on multiple nonconsecutive sections of the same tumor using a p-glycoprotein-specific monoclonal antibody, JSB-1.

Association of tumor washout rates and accumulation of technetium-99m-MIBI with expression of P-glycoprotein in lung cancer.

Unlabelled: In a prospective study, we correlated the washout rates of 99mTc-sestamibi (MIBI) and the degree of MIBI accumulation with the expression of P-glycoprotein (Pgp) in tumor tissues in a total of 46 patients with lung cancer.

Methods: All patients underwent early (30 min) and delayed (3 hr) MIBI imaging and bronchoscopic biopsy before initiation of chemo- or radiotherapy. The interval between biopsy and imaging varied between 2 and 10 days.

Double-phase Tc-99m-SestaMIBI SPECT imaging in a case of glomus jugulare tumor.

We performed a double-phase Tc-99m-SestaMIBI SPECT study on a patient who presented with a mass located at the skull base. The results were compared with double-phase T1-201 SPECT study. Early phase (30 min) SPECT images of both radiopharmaceuticals demonstrated increased radiotracer uptake in the region of the tumor.

Monitoring response to therapy with thallium-201 and technetium-99m-sestamibi SPECT in nasopharyngeal carcinoma.

Unlabelled: This study prospectively assessed the value of 201Tl and 99mTc-sestamibi (MIBI) SPECT in monitoring disease regression/progression as compared with MRI findings in patients with nasopharyngeal carcinoma (NPC) having radiotherapy with or without chemotherapy.

Methods: Eighteen patients (age range 15-78 yr, mean 45 yr) had consecutive SPECT imaging using a dual-head gamma camera after the injection of 111 MBq 201Tl and 555 MBq MIBI before therapy and at 3 mo and 6 mo after completion of therapy. A total of 106 SPECT studies was correlated with contemporaneous MRI studies.

Clinical validation of the influence of P-glycoprotein on technetium-99m-sestamibi uptake in malignant tumors.

Unlabelled: We prospectively studied 48 patients with either breast cancer (30 patients) or lung cancer (18 patients) to ascertain the relationship between the degree of accumulation of 99mTc-sestamibi and the expression of p-glycoprotein in tumor tissues.

Methods: During initial presentation (37 patients) or post-therapy evaluation (11 patients), the patients underwent contemporaneous 99mTc-sestamibi imaging and biopsy (30 patients) or surgery (18 patients). The interval between surgery/biopsy and imaging varied between 3 and 15 days.

Effect of an additional atropine injection during dobutamine infusion for myocardial SPET.

The aim of this study was to examine the value of an additional atropine injection in patients who do not achieve an adequate heart rate during dobutamine infusion for myocardial perfusion SPET (single photon emission tomography). Patients undergoing dobutamine myocardial SPET who failed to achieve > or = 85% of their age-predicted maximal heart rate at the end of dobutamine infusion (D protocol) had a second dobutamine myocardial SPET study on a separate day with the addition of an atropine injection during the dobutamine infusion (D + A protocol). Twenty-nine patients were studied.

A comparative study of technetium-99m sestamibi and technetium-99m tetrofosmin single-photon tomography in the detection of nasopharyngeal carcinoma.

The intention of this prospective study was to compare the diagnostic potential of technetium-99m sestamibi (MIBI) and a novel radiotracer, 99mTc-Tetrofosmin (Tetro), for the assessment of primary nasopharyngeal carcinoma (NPC) and the differentiation of residual disease from post-therapy changes. A total of 38 patients underwent MIBI and Tetro single-photon emission tomography (SPET) imaging at initial presentation (n=22) or following therapy (n=16). The findings were correlated with computed tomography or magnetic resonance imaging (MRI) on a site-by-site basis.

Dobutamine thallium-201 myocardial SPECT in patients with left bundle branch block and normal coronary arteries.

Unlabelled: Dobutamine is a positive inotropic and chronotropic agent and is being widely used as a pharmacologic stress agent in patients unable to achieve maximal dynamic exercise test. The purpose of the current study was to document the dobutamine induced false-positive septal defect in terms of its frequency and extent on 201Tl myocardial SPECT in patient with left bundle branch block (LBBB).

Methods: Twenty-five symptomatic patients with LBBB underwent dobutamine and redistribution 201Tl myocardial SPECT studies.

Can bone scintigraphy detect additional metastatic sites unrevealed by CT in patients with recurrent ovarian carcinoma?

A patient who presented with recurrent ovarian carcinoma with elevated levels of CA 125 was evaluated for skeletal metastases by routine whole body bone scintigraphy. Although no bone metastasis was visualized, there was intense accumulation of tracer in the soft tissues corresponding to the liver, pelvis, and intestinal/peritoneal surface, suggestive of metastatic disease. Although liver and pelvic soft tissue metastases were confirmed by CT and USG, intestinal/peritoneal metastases could not be disclosed by either modality.

Pre- and post-therapy thallium-201 and technetium-99m-sestamibi SPECT in nasopharyngeal carcinoma.

Unlabelled: We prospectively studied the diagnostic potential of 201Tl and 99mTc-sestamibi (MIBI) SPECT for evaluating the extent of primary disease and differentiating residual/recurrent disease from post-therapy changes in patients with nasopharyngeal carcinoma (NPC).

Methods: Fifty patients (20 initial presentation, 30 post-therapy evaluation) underwent 201Tl and MIBI imaging. The findings were correlated with CT/MRI results.

Segmental ATN in a kidney with a single artery transplanted from living related donor.

A sequential 99mTc-MAG3 renogram of a 20-year-old male who received a kidney from a living related donor is presented. Pre-transplant angiography of the donor showed the kidney had a single renal artery with upper and lower branches. The transplantation procedure was uneventful, allowing rapid simultaneous perfusion to the entire kidney.

Comparison of 99mTc(V)-DMSA, 201Tl and 99mTc-MIBI imaging in the follow-up of patients with medullary carcinoma of the thyroid.

Radionuclide scanning with tumour-seeking agents such as pentavalent technetium-99m dimercaptosuccinic acid [99mTc(V)-DMSA], thallium-201 and technetium-99m sestamibi (MIBI) has been reported to be useful in the detection of medullary thyroid carcinoma (MTC). We undertook a study in 14 MTC patients to determine the comparative imaging potential of 201Tl, MIBI and 99mTc(V)-DMSA in the detection of recurrent or metastatic MTC. All patients underwent total thyroidectomy and had persistently elevated serum calcitonin levels after the surgery.

Influence of immediate post-therapy bone scintigraphy in the assessment of response to therapy in a case of nasopharyngeal carcinoma.

A patient with undifferentiated stage IV (T3N3M0) nasopharyngeal carcinoma (WHO type III) underwent pre- and one-month post-therapy bone scintigraphy as part of an ongoing trial combining scintigraphic and radiographic modalities. The patient had advanced disease in the nasopharynx and bulky cervical lymph nodes at presentation. Initial bone scintigraphy performed 10 days prior to therapy was negative for bone metastases.

Renovascular hypertension due to Takayasu's arteritis demonstrated by Tc-99m ethylenedicysteine captopril scintigraphy.

A 34-year-old woman with severe hypertension underwent Tc-99m ethylenedicycteine (Tc-99m EC) captopril renal scintigraphy. There was bilateral parenchymal retention of the tracer suggesting renal artery stenosis. Angiography confirmed bilateral renal artery stenosis and also demonstrated contour irregularities of the abdominal aorta, and stenosis in mesenteric and subclavian arteries with increased collateral circulation consistent with Takayasu's arteritis.

The diagnosis of renovascular hypertension with technetium-99m-ethylenedicysteine captopril scintigraphy.

Rationale And Objectives: The authors present preliminary findings on the diagnosis of renovascular hypertension with technetium-99m-ethylenedicysteine (99mTc-EC).

Methods: Thirty-nine patients referred to the nuclear medicine department with clinical evidence of renovascular hypertension were included in the study. Baseline and captopril scintigraphies were done on separate days after the injection of 185 MBq of 99mTc-EC.

Technetium-99m-ethylenedicysteine in the diagnosis and follow-up of renovascular hypertension.

Technetium-99m-ethylenedicysteine (99mTc-EC) captopril scintigraphy performed in a patient with severe hypertension revealed increased parenchymal retention in the left kidney, suggesting renal artery stenosis. After angiographic confirmation of renal artery stenosis, percutaneous transluminal angioplasty (PTA) was performed on the left renal artery. Captopril scintigraphy after PTA showed normal findings with no evidence of parenchymal retention, consistent with reversal to normal kidney functions.

Silent myocardial ischemia in Behçet's disease.

Objective: Behçet's disease (BD) is a multisystemic disorder usually described as a triple symptom complex consisting of aphthous stomatitis, genital ulcerations, and uveitis. Vasculitis is a key feature of the disease, which may lead to functional disturbances in highly vascularized organs. However, cardiac involvement is seldom recognized.

Clinical evaluation of metastases of malignant melanoma imaging with 99Tcm-glutathione and 99Tcm-anti-melanoma antibody: a comparative study.

The aim of this investigation was to test for the scintigraphic detection of metastases of malignant melanoma with a new radiopharmaceutical, 99Tcm-glutathione (99Tcm-GSH), in comparison with 99Tcm-anti-melanoma antibody (99Tcm-AMAb). Glutathione was labelled with 99Tcm by a Sn2+ reduction method with an efficiency of > 99% as determined by instant thin layer chromatography (ITLC). Anti-melanoma antibody was obtained as a kit from SORIN (Italy) and labelled with 99TcmO-4.

The visualization of pulmonary tuberculosis with Tc-99m (V) DMSA and Tc-99m citrate in comparison to Ga-67 citrate.

Two patients with active tuberculosis confirmed by chest radiography and positive sputum smears were included in this study to determine whether a Tc-99m labeled agent, such as DMSA or citrate could localize such lesions in comparison to Ga-67 citrate. Both patients had Tc-99m (V) DMSA, Tc-99m citrate, and Ga-67 citrate scanning at 1-day to 5-day intervals. Both patients had positive scan findings with all three radiopharmaceuticals.

The value of Tc-99m citrate scintigraphy in chronic osteomyelitis. An indicator of the involved bone.

The authors present a prospective analysis of Tc-99m MDP and Tc-99m citrate scintigraphy in 29 patients who were clinically suspected of having chronic osteomyelitis. All of the patients showed increased Tc-99m MDP uptake on bone scintigraphy involving the area of concern. However, Tc-99m citrate scintigraphy clearly identified the patients with osteomyelitis (N = 18) confirmed either by biopsy or clinical follow-up.