Impact of 131I-SPECT/CT images obtained with an integrated system in the follow-up of patients with thyroid carcinoma.

PURPOSE: The purpose of the study was to determine the diagnostic impact of 131I-SPECT/CT imaging compared with conventional scintigraphic evaluation in the follow-up of patients with thyroid carcinoma. METHODS: Seventy-one patients with thyroid carcinoma underwent concurrent 131I-SPECT/CT, using an integrated imaging system, at various stages of their disease in order to evaluate foci of uptake detected on planar whole-body images. RESULTS: SPECT/CT imaging had an incremental diagnostic value in 57% (41/71) of patients. Uptake in the neck was evaluated in 61 patients, and SPECT/CT imaging in this region had an incremental diagnostic value in 27% of the whole patient population (19/71). Low-resolution integrated CT images allowed for the precise characterization of equivocal neck lesions on planar imaging in 14/17 patients and changed the assessment of the lesion location in five patients as compared with planar studies. Thirty-six patients underwent SPECT/CT for evaluation of foci of uptake distant from the neck. SPECT/CT imaging improved characterization of equivocal foci of uptake as definitely benign in 13% (9/71) of patients. Precise localization of malignant lesions to the skeleton was possible in 17% (12/71) and to the lungs versus the mediastinum in 6% (5/71) of patients. CONCLUSION: Integrated 131I-SPECT/CT was found to have an additional value over planar imaging in patients with thyroid cancer for correct characterization of equivocal tracer uptake seen on planar imaging as well as for precise localization of malignant lesions in the neck, chest, and skeleton. SPECT/CT optimized the localization of 131I uptake to lymph node metastases versus remnant thyroid tissue, to lung versus mediastinal metastases, and to the skeleton. It also had a further clinical impact on patient management by influencing referral for 131I treatment, tailoring of the administered radioiodine dose, and/or the addition of surgery or external radiation therapy when indicated.

Unusual presentation of mastoid eosinophilic granuloma in a young patient.

Eosinophilic granuloma is a well-recognized form of Langerhans cell histiocytosis, most commonly involving the skull bones, usually with an excellent prognosis. Recurrent and difficult to recognize osteolytic lesions of the skull are encountered only rarely. A patient with recurrent eosinophilic granuloma of the skull is reported. In spite of appropriate multimodality treatment, there were several recurrences, most recently with involvement of the mastoid process. Imaging studies revealed extensive involvement of surrounding structures with expansion of the tumor into the middle cranial fossa and slight pressure on the antero-medial portion of the temporal lobe of the brain. Despite extensive involvement, the patient had no complaints. Because of the rarity of such silent and unpredictable lesions, a systematic approach with regular CT and MRI follow-up is suggested.

CT angiography of the carotid arteries in trauma to the neck.

OBJECTIVES: serious vascular injuries to the neck may be asymptomatic or masked by other life-threatening conditions. Angiography, the "gold standard" vascular imaging modality, is an invasive procedure. Moreover, it is time-consuming and thus may delay a needed vascular intervention. The results of screening angiography are negative in more than 80% of cases. Therefore other less invasive and faster screening tests, such as the Doppler ultrasound and magnetic resonance angiography, have been tested. This retrospective study was done to evaluate the use of CT angiography (CTA) in suspected vascular injuries of the neck. METHODS: from 1995 to 1998, 16 patients with suspected traumatic carotid artery injury underwent CTA. Twelve of these patients had penetrating injuries and four had blunt injuries to the neck. CTAs were obtained by Elscint Twin Flash Spiral Scanner, while MIP reconstructions were carried out on an Omnipro, Elscint (Indy, Silicon Graphics) work station and interpreted by a radiologist. RESULTS: all the CTAs were diagnostic. Positive findings included one complete tear of the right common carotid artery (confirmed by surgery) due to a penetrating injury and one bilateral internal carotid artery thrombosis after blunt injury to the neck. In addition, three patients with multiple trauma were operated on, due to either proximity only or questionable neurological findings. Surgical exploration confirmed the negative findings seen on CTA. CONCLUSION: CT angiography of the carotid arteries in cervical trauma may be used as an accurate decisive tool for a needed surgical intervention. More studies with larger number of patients and comparison with angiography are needed.

Color-coded duplex ultrasound compared to CT angiography for detection and quantification of carotid artery stenosis.

OBJECTIVE: The purpose of this study was to compare findings on color-coded duplex ultrasound and CT angiography for grading internal carotid artery stenosis, and to investigate whether both these imaging modalities are necessary for an accurate diagnosis of carotid stenosis in the pre-surgical assessment of the internal carotid artery. PATIENTS AND METHODS: We examined 92 internal carotid arteries from 46 randomly chosen patients with suspected carotid stenosis by color-coded duplex ultrasound and by three-dimensional CT angiography (CTA). This retrospective study adhered to international guidelines with gradings of mild, moderate, severe, and occlusive carotid disease. RESULTS: The study demonstrated agreement between the degree of stenosis found on color-coded duplex ultrasound and that found on CTA in 78% of cases overall and in 79% of patients requiring surgical intervention. When compared to CTA, color-coded duplex ultrasound yielded a sensitivity of 78.9% and a specificity of 96.3%. Although findings on color-coded duplex ultrasound and CTA were comparable, disagreement affecting treatment decision occurred in 10:92 arteries. CONCLUSION: CTA was not found to be beneficial for patients exhibiting mild stenosis on color-coded duplex ultrasound, as none of the mild groupings found by sonography were interpreted as severe or occluded by CTA. However, CTA may be an important adjunct to color-coded duplex ultrasound regarding the categories of moderate, severe and occluded when carotid endarterectomy is considered.

Ewing's sarcoma of the facial zygomatic area bones in a young child: a case presentation.

We present the case of a young patient with Ewing's sarcoma of the facial zygomatic area bones. This type of tumor in a very young child is a rare event and poses significant diagnostic and therapeutic challenges for the attending physician. In this case, the diagnosis was made by a computed tomography scan with subsequent histological confirmation. The differential diagnoses and therapeutic options are discussed.

Renal pyelectasis in pregnancy: correlative evaluation of fetal and maternal collecting systems.

OBJECTIVE: The current study is aimed at assessing the possibility of a statistical relationship between fetal and maternal collecting system dilatation during pregnancy. STUDY DESIGN: Two hundred thirty consecutive pregnant women and their fetuses (20 to 40 weeks' gestation) were simultaneously examined by ultrasonography. The renal collecting systems were measured, and the frequency of dilatation was subjected to chi 2 analysis. The temporal incidence of fetal pyelectasis was compared with the maternal incidence. RESULTS: Dilatation of maternal collecting systems was detected in 91 of 230 patients (40%) and fetal pyelectasis occurred in 60 of 230 (26%). Fetal pyelectasis was 5.6 times more likely to occur in fetuses of mothers with dilated collecting systems. Furthermore, the temporal incidence of fetal pyelectasis throughout pregnancy appeared similar to that of maternal pyelectasis. CONCLUSION: This study points out the existence of a statistically significant association between maternal and fetal collecting system dilatation during pregnancy.