Spiral CT of pulmonary nodules: interobserver variation in assessment of lesion size

The aim of this study was to assess interobserver variability in size determination of pulmonary nodules at spiral CT. Twenty-three patients with known pulmonary nodules (diameter 2–40 mm, mean diameter 7 mm) underwent spiral chest CT (collimation 5 mm, pitch 1). Images were reconstructed at 3- and 5-mm intervals (RI). Hard copies were analyzed by two radiologists who recorded every nodule with regard to location, diagnostic confidence (“definite,”“probable”) and nodule size in increments of 1 mm with specific attention to correct classification into one of three size classes (≤ 5 mm, 6–10 mm, > 10 mm). Interobserver variability was determined with Pearson's correlation coefficient and k measure. Of a total of 286 nodules, 103 nodules were found accordingly by both readers at 3 mm RI, and 96 at 5 mm RI. There was a good correlation of measurements (in millimeters) between both readers (Pearson's correlation coefficient: 0.89–0.95). Interobserver variability in categories was good at both reconstruction intervals (k: 0.61 at 3 mm, 0.74 at 5 mm RI) and very good (0.81) at 5 mm RI when uncertain nodules were excluded. Spiral CT allows reproducible size determination of pulmonary nodules as shown by good interobserver agreement in exact size measurement and categorization into three size classes. Received: 2 September 1999; Revised: 24 January 2000; Accepted: 27 January 2000     

Reproducibility of diurnal variation in sub-maximal swimming

Swimming training is characterised by the use of early morning and evening training sessions. The purpose of the present study was to investigate if the physiological and kinematic responses to swimming a typical training set are affected by time of day. Seven male collegiate swimmers (age 22 +/- 4 years; height 1.8 +/- 0.1 m; mass 82.1 +/- 4.1 kg) completed a standardised 600 m warm up followed by a 10 x 100 m sub-maximal freestyle set twice a day (06:30-08:00 h and 16:30-20:00 h) on three separate days. Swimming speed was controlled precisely throughout (limits of agreement multiplied/divided 1.00) using a new pacing device (Aquapacer, Challenge and Response, Inverurie, Scotland). Oral temperature (To), heart rate (HR), minute ventilation (VE), oxygen uptake (VO2), carbon dioxide expired (VCO2), respiratory exchange ratio (RER), capillary blood lactate (Bla), and glucose (BGL) were measured at rest and post exercise. Stroke rate (SR) and HR were measured during the first nine 100 m repetitions while rate of perceived exertion (RPE) was measured immediately after each 100 m. Significant diurnal variation was found at rest in To, HR, and VO2 on all three days and for VE and VCO2 on two of the days (P<0.05). During the training set no diurnal variation was evident in HR and SR responses or repetition times although RPE values were higher in morning trials compared to evening trials on two of the three days (P < 0.05). Post-exercise significant diurnal variation was found for To and blood glucose for two of the three days (P < 0.05). Therefore, although diurnal variation is evident at rest, there is no subsequent effect on physiological and kinematic responses during a sub-maximal training set following a standardised warm-up.     

Lymphangioleiomyomatosis: CT of diurnal variation of lymphangioleiomyomas.

PURPOSE: To evaluate the imaging and clinical features of lymphangioleiomyomas and to describe the phenomenon of diurnal variation in the size of lymphangioleiomyomas in patients with lymphangioleiomyomatosis. MATERIALS AND METHODS: One hundred twenty-eight patients with lymphangioleiomyomatosis underwent chest and abdominopelvic computed tomography (CT). Thirteen patients underwent CT in the morning and afternoon of the same day to assess diurnal variation in lymphangioleiomyoma size. RESULTS: Twenty-seven of 128 patients (21%) had 54 lymphangioleiomyomas. The vast majority (96%) of these masses contained material of low attenuation at CT. Associated CT findings included enlarged abdominal lymph nodes, pleural effusions, ascites, and dilatation of the thoracic duct. The prevalence of lymphangioleiomyomas was 15% in patients who had mild pulmonary disease, 19% in patients who had moderate disease, and 26% in patients who had severe disease. Diurnal variation in size of masses was demonstrated in 12 of 13 patients. Seven of the 27 patients who had masses underwent biopsy; all seven were confirmed to have lymphangioleiomyomas. The most common symptoms associated with lymphangioleiomyomas were bloating, abdominal pain, and edema of the lower extremities. The majority of the patients reported worsening of symptoms as the day progressed. CONCLUSION: Lymphangioleiomyomas are common in patients with lymphangioleiomyomatosis. Diurnal variation in size may explain worsening of symptoms during the day.     

Warm-up affects diurnal variation in power output

The purpose of this study was to examine whether time of day variations in power output can be accounted for by the diurnal fluctuations existent in body temperature. 8 recreationally trained males (29.8±5.2 yrs; 178.3±5.2 cm; 80.3±6.5 kg) were assessed on 4 occasions following a: (a) control warm-up at 8.00 am; (b) control warm-up at 4.00 pm; (c) extended warm-up at 8.00 am; and, (d) extended warm-up at 4.00 pm. The control warm-up consisted of dynamic exercises and practice jumps. The extended warm-up incorporated a 20 min general warm-up on a stationary bike prior to completion of the control warm-up, resulting in a whole body temperature increase of 0.3±0.2°C. Kinetic and kinematic variables were measured using a linear optical encoder attached to a barbell during 6 loaded counter-movement jumps. Results were 2-6% higher in the afternoon control condition than morning control condition. No substantial performance differences were observed between the extended morning condition and afternoon control condition where body temperatures were similar. Results indicate that diurnal variation in whole body temperature may explain diurnal performance differences in explosive power output and associated variables. It is suggested that warm-up protocols designed to increase body temperature are beneficial in reducing diurnal differences in jump performance.     

Listening to music affects diurnal variation in muscle power output

The purpose of this investigation was to assess the effects of listening to music while warming-up on the diurnal variations of power output during the Wingate test. 12 physical education students underwent four Wingate tests at 07:00 and 17:00 h, after 10 min of warm-up with and without listening to music. The warm-up consisted of 10 min of pedalling at a constant pace of 60 rpm against a light load of 1 kg. During the Wingate test, peak and mean power were measured. The main finding was that peak and mean power improved from morning to afternoon after no music warm-up (p<0.001 and p<0.01, respectively). These diurnal variations disappeared for mean power and persisted with an attenuated morning-evening difference (p<0.05) for peak power after music warm-up. Moreover, peak and mean power were significantly higher after music than no music warm-up during the two times of testing. Thus, as it is a legal method and an additional aid, music should be used during warm-up before performing activities requiring powerful lower limbs' muscles contractions, especially in the morning competitive events.     

Sporadic lymphangioleiomyomatosis and tuberous sclerosis complex with lymphangioleiomyomatosis: comparison of CT features

PURPOSE: To retrospectively compare the frequencies of computed tomographic (CT) findings in patients with lymphangioleiomyomatosis (LAM) and patients with tuberous sclerosis complex (TSC) and LAM. MATERIALS AND METHODS: Institutional review board approval and informed consent were obtained for the HIPAA-compliant study. In 256 patients with LAM (mean age, 44 years) and 67 patients with TSC/LAM (mean age, 40 years), CT scans of the chest, abdomen, and pelvis were reviewed by a single radiologist. The fraction of lung involvement with cysts was estimated from high-spatial-resolution CT scans. Other findings assessed included noncalcified pulmonary nodules, pleural effusion, thoracic duct dilatation, hepatic and renal angiomyolipomas (AMLs), lymphangioleiomyoma (LALM), ascites, nephrectomy, and renal embolization. Confidence intervals and hypothesis tests of differences in frequencies, comparison of age quartiles, RIDIT analysis, analysis of variance, and correlation coefficients were used in the statistical analysis. RESULTS: Patients with LAM had more extensive lung involvement (RIDIT score, 0.36) and higher frequency of LALM (29% vs 9%, P<.001), thoracic duct dilatation (4% vs 0, P=.3), pleural effusion (12% vs 6%, P=.2), or ascites (10% vs 6%, P=.3). Patients with TSC/LAM had higher frequency of noncalcified pulmonary nodules (12% vs 1%, P<.01), hepatic (33% vs 2%, P<.001) and renal (93% vs 32%, P<.001) AMLs, nephrectomy (25% vs 7%, P<.001), or renal artery embolization (9% vs 2%, P<.05). CONCLUSION: The extent of lung disease is greater in LAM than TSC/LAM. Hepatic and renal AMLs and noncalcified lung nodules are more common in TSC/LAM, while lymphatic involvement-thoracic duct dilatation, chylous pleural effusion, ascites, and LALM-is more common in LAM.     

A mathematical description of the diurnal variation of radon progeny.

The variation of the alpha radioactivity in the air near the ground and the ground-level total gamma radiation has been monitored in North-eastern Greece over several days. Meteorological information regarding the temperature of the air and humidity has been simultaneously recorded. The alpha-radioactivity shows a periodic diurnal variation with a peak in the morning followed by a decrease in the afternoon; then, the variation rises again to the peak the next morning. The variation of the ground gamma-radiation follows that of the air alpha-radioactivity. Furthermore, their significant dependence on the air temperature and humidity is confirmed, rising with an increase in humidity and a decrease in temperature. Hence, a mathematical function has been developed to describe the diurnal variation of the alpha-radioactivity in terms of the ground-level gamma-radiation and the meteorological variables of temperature and humidity.     

Imaging features of lymphangioleiomyomatosis: diagnostic pitfalls

OBJECTIVE: The objective of this article is to illustrate CT findings that may be misinterpreted and lead to unnecessary biopsy or surgical procedures in patients with lymphangioleiomyomatosis. CONCLUSION: Sequelae of pleurodesis, acutely hemorrhagic renal angiomyolipomas, and lymphatic involvement with lymphangioleiomyomatosis including enlarged lymph nodes and lymphangioleiomyomas are common benign conditions seen in patients with lymphangioleiomyomatosis that may be misdiagnosed on CT for malignancy and may prompt unnecessary biopsy and surgery. Ruptured abdominal pelvic lymphangioleiomyomas may be mistaken for appendicitis and other acute abdominal pelvic events.     

Pulmonary lymphangioleiomyomatosis: high-resolution CT findings in four cases

Lymphangioleiomyomatosis is a rare disease of unknown cause that affects women of reproductive age. It is characterized by progressive proliferation of smooth muscle in the lung. The patients present with progressive shortness of breath, pneumothorax, chylous effusion, and hemoptysis. Four patients with biopsy-proved lymphangioleiomyomatosis of the lung were evaluated using high-resolution CT. In all patients, the scan showed well-defined cystic air spaces, surrounded by uniformly thin walls, distributed diffusely throughout both lungs. The cystic air spaces ranged in size from a few millimeters to 5 cm. Pathologically, these cysts were predominantly bounded by normal-looking parenchymal components, with occasional patchy involvement by a smooth-muscle proliferative process. The CT appearance of lymphangioleiomyomatosis differs quite distinctly from that of other diseases that can cause cystic air spaces, such as fibrosing alveolitis, neurofibromatosis, and bronchiectasis, and less distinctly from pulmonary emphysema and eosinophilic granuloma. Our experience in these few cases suggests that the high-resolution CT findings in lymphangioleiomyomatosis are characteristic of the disease.     

Prognostic significance of lesion size for glioblastoma multiforme.

From March 1974 to December 1976, 56 patients with glioblastoma multiforme had precraniotomy computed tomography (CT) scans from which the lesion size was determined by measuring the cross-sectional area. Thirty-two patients underwent surgery followed by irradiation, and 24 had surgery followed by irradiation and chemotherapy. There was no difference in survival between the 16 patients with small lesions and the 16 patients with large lesions in the surgery plus radiation alone group, nor in the 16 patients with small and 8 patients with large lesions in the surgery, radiation and chemotherapy group. Minimum follow-up was one year. Other possible prognostic factors including age, tumor grade, radiation dose, and performance status were comparable for each subgroup. Lesion size in glioblastoma multiforme appears unrelated to prognosis.     

Observer variation in bone lesion detection in thoraco-abdominal visceral CT images

This study measured missed bone diagnosis on CT performed for lymph nodes or visceral spread of cancers and lymphomas. A bone-expert reading was compared to that of visceral-cancer oriented observers. From 100 examinations, 65% of bone abnormalities were not described by current reporting of cancer cases. Changes in windowing and contrast of the image produced large variations in CT readings. A slow search with different windowing decreases the false-negative ratio. A fast reading with invariable viewing parameters increases false interpretations, even for experienced radiologists.     

MRI demonstration of a reversible lesion in cerebral deep white matter in thrombotic thrombocytopenic purpura

We report a 75-year-old woman with thrombotic thrombocytopenic purpura (TTP) whose MRI showed diffuse abnormal signal in the deep white matter. She was successfully treated, and this abnormal signal disappeared. This finding indicates that the deep white matter is involved in TTP; the lesion may reflect reversible microangiopathy and brain oedema.     

Coexistence of lung cancer and tuberculoma in the same lesion: demonstration by high resolution and contrast-enhanced dynamic CT

We report a case of coexistence of lung cancer and tuberculoma in the same lesion. The component parts of lung cancer and tuberculoma were identified on the basis of morphology on high-resolution CT as well as enhancement patterns and time-attenuation curves by contrast-enhanced dynamic CT.