Diagnostic confidence and image quality of CT pulmonary angiography at 100 kVp in overweight and obese patients.

AIM: To compare image quality and diagnostic confidence of 100 kVp CT pulmonary angiography (CTPA) in patients with body weights (BWs) below and above 100kg. MATERIALS AND METHODS: The present retrospective study comprised 216 patients (BWs of 75-99kg, 114 patients; 100-125kg, 88 patients; >125kg, 14 patients), who received 100 kVp CTPA to exclude pulmonary embolism. The attenuation was measured and the contrast-to-noise ratio (CNR) was calculated in the pulmonary trunk. Size-specific dose estimates (SSDEs) were evaluated. Three blinded radiologists rated subjective image quality and diagnostic confidence. Results between the BW groups and between three body mass index (BMI) groups (BMI <25kg/m(2), BMI = 25-29.9kg/m(2), and BMI ≥30kg/m(2), i.e., normal weight, overweight, and obese patients) were compared using the Kruskal-Wallis test. RESULTS: Vessel attenuation was higher and SDDE was lower in the 75-99kg group than at higher BWs (p-values between <0.001 and 0.03), with no difference between the 100-125 and >125kg groups (p = 0.892 and 1). Subjective image quality and diagnostic confidence were not different among the BW groups (p = 0.225 and 1). CNR was lower (p < 0.006) in obese patients than in normal weight or overweight subjects. Diagnostic confidence was not different in the BMI groups (p = 0.105). CONCLUSION: CTPA at 100 kVp tube voltage can be used in patients weighing up to 125kg with no significant deterioration of subjective image quality and confidence. The applicability of 100 kVp in the 125-150kg BW range needs further testing in larger collectives.

[Fifteen years experience in the surgical treatment of primary hyperparathyroidism]. / Tizenöt év alatt szerzett tapasztalataink a primer hyperparathyreosis sebészi kezelésében.

We measured the efficacy of preoperative localization techniques and results of parathyroidectomy in patients with primary hyperparathyroidism (HPT). From 1986 to 2001, 92 patients were treated with primary HPT. Preoperative localization technique was used in all patients (US n = 85, Tc-99m-sestamibi/Tc-99m-pertechnetate subtraction scintigraphy n = 67, CT n = 18, MRI n = 14) to visualize the abnormal parathyroids. Results of localization studies were compared with surgical and pathological findings. Bilateral neck exploration was carried out in each patient for the identification of all parathyroid glands. If parathyroid adenoma was diagnosed, exstirpation of the abnormal parathyroid was performed. If diffuse hyperplasia was diagnosed, subtotal parathyroidectomy (3 1/2) was performed. The overall sensitivity was 94% for scintigraphy, 74% for US, 67% for CT and 50% for MRI. The PPV was 97% for scintigraphy, 92% for US, 100% for CT and for MRI. At surgery 66 patients had single adenomas and 3 patients had double adenomas. Diffuse hyperplasia was diagnosed in 21 and parathyroid carcinoma was found in 2 patients. Persistent HPT was noted in 1 patient. Recurrent HTP occurred 4 times. After a second operation their HPT disappeared. In conclusion, the sensitivity of Technetium-99m-sestambi and Technetium-99m-pertechnetate subtraction scanning was significantly superior compared to other localization methods. The use of these sensitive preoperative technique can improve the success rate, and decrease the incidence of persistent and recurrent HPT.