摘要:

Chronic idiopathic thrombocytopenia purpura is an immunologically mediated disorder resulting in disordered platelet kinetics and potentially life-threatening thrombocytopenia. Failure of medical therapy is an indication for splenectomy, and responses are seen in 70% of patients after this procedure. An important cause of relapse after splenectomy is the presence of accessory spleens. The authors describe a patient with chronic idiopathic thrombocytopenia purpura who had a relapse of symptoms 4.5 years after splenectomy. Tc-99m heat-denatured RBC planar and SPECT studies revealed the presence of multiple (more than 13) accessory spleens, but few of them were localized anatomically using computed tomography.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Extramedullary plasmacytoma is a rare form of plasma cell tumor occurring in a wide variety of organs and tissues. Most tumors occur in the head and neck, involving the nasal cavity, paranasal sinuses, and upper airway. Tl-201 and Ga-67 scan findings in a patient with extramedullary plasmacytoma in the right side of the chest wall are presented. Only a few publications have described Tl-201 or Ga-67 uptake in extramedullary plasmacytoma. This is the first report of both Tl-201 and Ga-67 uptake in an extramedullary (or intramedullary) plasmacytoma.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Poorly differentiated insular thyroid carcinoma is now classified as a separate entity among other tumors of the thyroid gland. Its histologic pattern and its clinical course are regarded as intermediate between well differentiated and anaplastic thyroid cancer. Insular carcinoma accumulates I-131, but no data exist regarding its fluorodeoxyglucose (FDG) positron emission tomographic (PET) uptake. The authors report F-18 FDG PET, Tc-99m MIBI, and radioiodine imaging features in a 63-year-old patient with metastatic insular thyroid carcinoma. After total thyroidectomy (for poorly differentiated insular carcinoma pT3a), the patient was referred for radioiodine ablation. No signs of recurrence were present until 16 months later, when thyroglobulin levels increased. An I-131 scan showed a single lesion in the right lung, and further radioiodine treatment was administered (cumulative dose [530 mCi], 19,610 MBq I-131). Three years after the initial diagnosis, FDG-PET and Tc-99m MIBI scans were performed within 5 days during thyroxine treatment. After that, thyroxine substitution was withdrawn; 6 weeks later, an I-131 whole-body scan was performed. Both radioiodine and MIBI images showed increased tracer uptake in the known lung lesion. However, FDG PET showed a normal tracer distribution. Magnetic resonance and computed tomographic imaging confirmed a 12-mm lesion in the right upper lobe. These findings support the concept of the “flip-flop phenomenon” in insular thyroid carcinoma, an alternating pattern of metastases with either I-131 or FDG-uptake. Despite poorly differentiated histologic findings, glucose metabolism was not increased in this patient with an insular tumor.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

PurposeThe lymphatic system may show variations throughout the entire body. Knowledge of the variations and aberrant lymph drainage are important when planning surgical treatment and radiotherapy. The aim of this study was to evaluate the intratumoral injection technique in the detection of lymphatic drainage of proved or possibly malignant cold thyroid nodules.Materials and MethodsThe study group consisted of 13 patients with palpable solitary cold thyroid nodules. None of the patients had cystic nodules on ultrasound examination. After fine-needle aspiration biopsy (at least 3 days later), 15 MBq (0.4 mCi) Tc-99m nanocolloid particles in a small volume (0.2 ml) were injected into the nodule. Dynamic images (60 frame × 1 minute) were acquired during the first hour, followed by static anterior and lateral images at 90 and 120 minutes.ResultsRadiopharmaceutical was present in the systemic circulation in two patients, possibly as a result of paratumoral injection. Eleven patients had intratumoral accumulation in early frames. Lymph nodes draining the thyroid nodule were visualized in 10 of 11 patients. In the dynamic acquisition period of 7 of 10 patients, the first draining lymph node could also be identified. Only 5 of 13 patients had malignant nodules. Lymphatic metastases were detected in one patient’s specimens.ConclusionsPreoperative visualization of lymphatic pathways may be used when planning for thyroid cancer surgery. Sentinel node detection could yield valuable additional information in these patients.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Renovascular disease is an important cause of hypertension in children and is associated with considerable morbidity and mortality risks. Secondary hypertension is more common in children than in adults, with children accounting for 75% to 80% of cases. In 70% of secondary hypertension in children, the cause is fibromuscular hyperplasia. Other associated conditions are aorto-aortitis, the midaortic syndrome, and Williams-Bueren syndrome. Imaging techniques have an important role in the early discovery of renal artery stenosis. Although renal arteriography remains the definitive method, noninvasive and less invasive radiographic procedures such as ultrasonography with duplex Doppler scanning and radionuclide scintigraphy have been used as adjunct diagnostic tools in children. The authors describe three young children with renovascular hypertension in whom dynamic radionuclide scintigraphy with Tc-99m MAG3 played an essential role in the diagnosis of renovascular hypertension.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

In a renal transplant recipient with persistently poor graft function, the flow phase of a renal scan incidentally revealed multiple venous collaterals with focally increased vascular activity near the left lobe of the liver (quadrate lobe). This was initially assumed to represent superior vena cava (SVC) obstruction. A renal biopsy was contemplated to exclude acute rejection because of a nondiagnostic flow phase (loss of a bolus effect). However, because the possibility of venous obstruction at the level of the subclavian and/or brachiocephalic veins (without involving the SVC) also existed, another renal scan was performed, with injection of radiotracer into the contralateral arm. This showed a patent SVC and reasonably preserved renal perfusion consistent with acute tubular necrosis. Subsequently, left subclavian vein obstruction was identified. The graft function improved with conservative management for acute tubular necrosis. These findings illustrate the danger of considering only SVC obstruction when collateral flow patterns and focal hot spots in the liver are present.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

PurposeThe authors describe a patient with F-18 fluorodeoxyglucose (FDG) uptake resulting from a bone infarct of a rib.Materials and MethodsA 52-year-old woman with a history of left breast cancer and total mastectomy 5 years earlier was examined for pain in her left rib cage in the past 2 weeks. A bone scan showed diffusely increased uptake in the left fifth rib, possibly suggestive of a metastasis. An FDG positron emission tomographic (PET) scan was performed to rule out metastatic disease.ResultsThe FDG PET images showed two focal areas of increased uptake in the fifth and sixth left ribs, consistent with bone metastases. The patient underwent excision of a long segment of her left fifth rib and the pathological findings were consistent with bone infarct, without definite signs of metastatic disease.ConclusionBone infarct can take up FDG, probably as a result of an inflammatory process.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

Monostotic Paget’s disease of the patella was detected with Tc-99m MDP and Tl-201 scans. Diffuse intense uptake of MDP in the left patella was observed on the blood-pool and late phases of the bone scan. Tl-201 imaging was performed to differentiate a malignant process and showed diffuse marked accumulation at the same site. Semiquantitative analysis of the patella region on both Tc-99m MDP and Tl-201 scans did not support a diagnosis of cancer. Radiographs showed the features of Paget’s disease of the bone. Findings of a pathologic evaluation were compatible with the diagnosis of osteitis deformans. This case represents the unusual skeletal involvement of monostotic Paget’s disease of the bone in the patella. Tl-201 accumulation in the Paget’s lesion was suggested to be caused by increased metabolic activity of the lesion but was not indicative of a malignant process.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

PurposeThe authors describe the clinical and bone scintigraphic findings of the SAPHO syndrome, which is characterized by synovitis, acne, palmoplantar pustulosis, hyperostosis, and osteitis. The case report illustrates the significance of bone scintigraphy in the diagnosis. It shows that Tc-99m MDP scanning can detect signs of arthritis not seen with other imaging methods, because the arthritis is inflammatory in nature and does not always cause bone erosion. Thus it is not visualized on plain radiographs. Knowledge of this disorder may help in the differential diagnosis of arthritis.Materials and MethodsTc-99m MDP bone scintigraphy was used to diagnose arthritic changes. Whole-body and multiple delayed spot images were obtained in a 39-year-old diabetic, hypertensive woman who had tenderness in the plantar aspect of her heels. Swelling of the small and large joints of the feet, ankles, knees, hips, right sacroiliac joints, and shoulders was noted. She also had hydradenitis suppurativa and a history of a previous episode in which the arthritis improved after surgical treatment for the hydradenitis.ResultsAll active joint lesions were visualized on the bone scan, including the arthritis, which was not detected with other imaging methods. They were all well demonstrated in the bone scintiscan. The scan findings, along with the presence of hydradenitis, led to the correct diagnosis of SAPHO syndrome.ConclusionTc-99m MDP bone scanning may be helpful in diagnosing arthritis as associated with the SAPHO syndrome.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID

摘要:

PurposeThe aim of this study was to investigate quantitatively the volume effect of the stomach on the prevention of intestinal artifacts in the rest phase on same-day exercise–rest Tc-99m tetrofosmin myocardial perfusion scintigraphy.Materials and MethodsThe study was performed in 81 consecutive patients (43 men, 38 women; mean age, 57 ± 9 years) who were referred for routine Tc-99m tetrofosmin exercise–rest SPECT myocardial perfusion imaging with normal scintigrams or completely normal inferior wall perfusion on visual assessment of SPECT images. Group A (control group, n = 41) and group B (n = 40) were given 200 ml milk to enhance the hepatobiliary clearance of tetrofosmin 30 minutes before the exercise SPECT acquisition study and just after the injection for the rest SPECT acquisition study. For the rest SPECT acquisition study, patients in group B were given, in addition to milk, a standard solid and fluid meal to enhance the volume of the stomach after the injection of Tc-99m tetrofosmin. In all patients, both exercise and rest SPECT acquisitions were started 45 minutes after the injection of Tc-99m tetrofosmin. Myocardial and abdominal activity were assessed on three separate views in the rest phase of the study, and the mean myocardium-to-abdomen count ratios were calculated. In addition, the presence of interfering intestinal activity was assessed visually on SPECT images. Infracardiac activity was described as absent when it was equal to lung background.ResultsThe myocardial-to-abdominal ratios were 1.38 ± 0.05 and 1.95 ± 0.04 in groups A and B, respectively (P< 0.0001). Interfering intestinal activity with varying degrees of intensity was seen in 20 patients in group A (49%) and in 5 patients in group B (13%;P< 0.001).ConclusionsThese results suggest that filling of the stomach with some fluid and solid food before rest acquisition on the same-day stress–rest protocol, because of its volume effect, may provide a high target-to-nontarget ratio for myocardial imaging and thus may reduce the frequency of intestinal artifacts.

ISSN:0363-9762    

出版商:OVID    

年代:2001

数据来源: OVID