Radiation dose optimisation in dynamic volume CT of the heart: tube current adaptation based on anterior–posterior chest diameter

To compare tube current adaptation based on 3 body mass index (BMI) categories versus anterior-posterior chest diameter (APD) for radiation dose optimisation in patients undergoing dynamic volume cardiac CT. Two cardiac imaging centres participated in the study. 20 patients underwent a prospectively triggered 320-slice single beat cardiac CT using the X-ray tube current [mA] manually adjusted to the patient’s BMI (group I). In 20 subsequent patients, the tube current was adapted according to the patient’s APD (group II). All other parameters were kept constant. Image noise was defined as the standard deviation of attenuation values and measured using a ROI in the descending aorta. Variation in image noise was statistically compared between both patient groups. Average and standard deviation of pixel noise were 29.1 HU and 14.8 HU in group I and 28.0 HU and 4.2 HU in group II. Inter-individual variation of pixel noise was significantly lower in group II compared to group I (p < 0.0001). Tube current adaptation based on APD is superior to stepwise adaptation based on BMI for optimising radiation dose in dynamic volume cardiac CT and therefore limits unnecessary radiation dose while ensuring diagnostic image quality in patients with diverse body habitus.     

Psychopathology in a community sample of children and adolescents: a developmental perspective

Psychiatric disorders, symptom clusters and adjustment problems in a community based sample comprised three age cohorts: 8, 12, and 17 years. The data indicated that anxiety symptoms decreased with age. Conduct problems increased with age for males, affective problems increased with age for females, and substance use and social anxiety increased with age for both sexes. Concerns about inadequacy also increases with age, but only for females. These gender-based developmental differences in psychopathology and other findings are discussed.     

Tibial nerve entrapment by a Baker cyst: case report

We report a rare case of degenerative joint disease of both knees, complicated by a Baker cyst. Our emphasis is on the role of electromyography and electrodiagnosis in the localization of this nerve entrapment syndrome. The patient presented with pain and swelling; venography revealed deep venous thrombosis of the right calf, including the popliteal and proximal superficial femoral vessels. The patient responded well to bed rest, analgesics, intravenous heparin and subsequent Coumadin anticoagulation, and was discharged two weeks later. Five weeks after onset of these acute problems, nerve conduction studies were done, leading to a diagnosis of Baker cyst with nerve entrapment. He responded well to knee joint aspiration and intraarticular prednisolone injection. Some evidence of improvement in the flexor hallicus longus muscle was detected at three-month follow-up.     

Noninvasive assessment of indomethacin therapy in patent ductus arteriosus in preterm infants

We performed 138 serial two-dimensional (2-D), M-mode, and Doppler echocardiographic studies to assess the efficacy of intravenous indomethacin (INDO) therapy for patent ductus arteriosus (PDA) in 41 preterm infants. Nine infants expired without sufficient echo data to warrant inclusion in the study. Of the remaining 32 infants, 12 (Group 1) required ligation despite INDO therapy, 18 (Group 2) responded to INDO or spontaneously closed their PDAs, and 2 were transferred to other hospitals with their PDAs still open and were lost to follow-up. The presence of PDA was verified by 2-D echo visualization of the ductus (high parasternal short-axis views) and Doppler demonstration of high velocity ductal flow toward the main pulmonary artery. The ratio of PDA lumen to aortic root inner diameter (Ao) was measured as well. Indication for surgical ligation was failure of the PDA to close after 3 or more courses of INDO. In Group 1, the PDA/Ao ratio was 0.45 +/- 0.10 standard error of the mean (SEM) pre-INDO, and 0.40 +/- 0.12 SEM post-INDO (immediately before ligation). In Group 2, the PDA/Ao ratio was 0.42 +/- 0.11 SEM pre-INDO, and 0.19 +/- 0.14 SEM at the end of INDO course (p less than 0.001), with 12 infants showing no ductal flow by Doppler. Follow-up six months after INDO therapy has shown no residual murmurs or other evidence of PDA in any INDO-closed infant. Five of the 18 infants have undergone repeated echocardiographic studies, all of which were negative for PDA patency or flow.(ABSTRACT TRUNCATED AT 250 WORDS)