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C Metreweli

Publications and source records attributed to C Metreweli.

At least 127 records · Page 7Linked to original sources
PubMed1998

Peritonsillar abscess appearance on intra-oral ultrasonography.

The ultrasound appearances of peritonsillar abscesses (PTA) in 15 patients with clinically suspected peritonsillar infection were assessed using intra-oral sonography and computed tomography (CT). The ultrasonic appearances of an isoechoic rim with a hypoechoic centre were seen in the majority of cases, but a homogeneous isoechoic pattern was also recognized. The different ultrasonic appearances did not correlate with the number of symptomatic days. A central hypoechoic area with a surrounding isoechoic rim pattern was less likely if the volume of pus relative to the whole abscess was less than 10% on CT. Although the percentage of necrosis within the abscesses increased with time, the homogeneous isoechoic appearing abscesses, with less than 10% necrosis, did not fit in temporally and based on our findings it was not possible to predict the ultrasound appearances according to the duration of symptoms.

Adolescent↗
PubMed1998

The role of ultrasound and oesophagography in the management of acute suppurative thyroiditis in children associated with congenital pyriform fossa sinus.

The thyroid is remarkably resistant to infection. Hence, when an infection does occur, the presence of a pyriform fossa sinus must be considered, particularly if it is recurrent and left sided. The aim of this paper is to alert radiologists to the existence, clinical presentation, and ultrasonographic and oesophagographic appearances of a pyriform fossa sinus. We present the role of ultrasound and oesophagography in five children with pyriform fossa sinus associated with suppurative thyroiditis. In four children the abnormality was on the left and on the right in one.

Abscess↗
PubMed1998

Alteration of thyroid blood flow during the normal menstrual cycle in healthy Chinese women.

The purpose of this study was to investigate the relationship between thyroid activity and the menstrual cycle by measuring the Doppler parameters of the superior thyroid arteries in women of reproductive age. The study was performed in 27 healthy Chinese women aged between 19 and 28 y for one menstrual cycle, and 25 age-matched healthy Chinese men for 3 weeks for comparison. In women, the peak systolic velocity increased from the follicular phase to the luteal phase, and the pulsatility index decreased from the follicular phase to the ovulatory phase and increased slightly in the luteal phase. In men, alterations in the pattern of thyroid blood flow were not observed; however, the average values of Doppler parameters during the study period in women were similar to those in men. The gender difference in the pattern of flow characteristics in the superior thyroid artery suggests effects of estrogen on thyroid function.

Adolescent↗
PubMed1998

The value of thyroid parenchymal echogenicity as an indicator of pathology using the sternomastoid muscle for comparison.

This study was undertaken to evaluate the diagnostic accuracy of comparison of the echogenicity of the thyroid gland with the sternomastoid muscle in diagnosis of thyroid disorders. Fifty healthy subjects underwent a thyroid ultrasound, and 80 patients with archived thyroid ultrasound examinations (50 thyrotoxicosis and 30 thyroiditis) were reviewed. Images were measured for the image density of the thyroid gland and the sternomastoid muscle, using a transmission densitometer. Healthy thyroid was relatively hyperechoic when compared with the sternomastoid muscle (100%). Of the thyrotoxic patients, 70% showed a relatively hyperechoic thyroid compared to 47% of the thyroiditis patients. Mean image density difference in healthy thyroid, thyrotoxicosis and thyroiditis ranged from 0.1 to 1, -0.42 to 0.83, and -0.55 to 0.58, respectively. In conclusion, the relative echogenicity of the thyroid gland when compared with the sternomastoid muscle may be useful to differentiate healthy thyroid from thyrotoxicosis and thyroiditis, but does not help to distinguish thyrotoxicosis from thyroiditis. An image density difference of less than 0.1 may be considered to be abnormal, whereas a value greater than 0.83 may be considered to be normal.

Adolescent↗
PubMed1998

Body fat estimation in children by magnetic resonance imaging, bioelectrical impedance, skinfold and body mass index: a pilot study.

OBJECTIVE: The aim of this study was to identify the clinical method to estimate body fat which gave best correlation of total body fat and percentage body fat as measured on MRI. METHODS: Magnetic resonance imaging (MRI) was used to estimate the total body fat volume and percentage body fat and this was compared with assessment by bioelectrical impedance (BEI), skinfold thickness and body mass index (BMI) in 8- to 12-year-old children. RESULTS: Total body fat measured on magnetic resonance imaging (TBF-MRI) significantly correlated with body mass index, triceps and subscapular skinfolds, and percentage body fat estimations by BEI. Multiple regression analysis showed that BMI and BEI together gave the best prediction of total body fat as measured on MRI from the equation: TBF-MRI=-25277.77+1457.61(BMI)+423.95(%fat-BEI), with R2=0.89. Percentage body fat measurement from MRI, BEI and skinfold were not significantly different but their results were not interchangeable. Linear regression of %body fat from MRI on those obtained from BEI and skinfold measurements showed a modest fit with R2=0.6973 and 0.5501, respectively. CONCLUSIONS: In children 8-12 years old, BMI gives a good estimation of the total body fat as measured on MRI. The estimation will be improved when both BEI and BMI are used in the prediction. Bioelectrical impedance has a low correlation with total body fat and its use alone in estimating total body fat is not recommended. Skinfold measurement also gives a reasonably good prediction of total body fat and addition of BMI and BEI does not improve the prediction. Both BEI and skinfold measurements give a modest prediction of %body fat measured by MRI method.

Adipose Tissue↗
PubMed1998

Magnetic resonance imaging evaluation of the pituitary gland and hypothalamus in thalassaemic children with elevated serum ferritin levels.

OBJECTIVE: Despite modern treatment with hypertransfusion and chelation therapy, growth retardation continues to be observed in a significant proportion of thalassaemic children. The underlying reason remains unclear, but hypothalamic-pituitary axis disorder has been implicated. We aimed to assess iron overloading in the hypothalamus and pituitary gland in thalassaemic children with elevated serum ferritin, with and without growth retardation. METHODOLOGY: Twelve thalassaemic children on hypertransfusion and chelation therapy with high serum ferritin were investigated with magnetic resonance imaging (MRI). Five children, all over 10 years of age, had growth retardation. Gradient recalled echo sequence was used to highlight any susceptibility effect that could be due to iron in the hypothalamus or pituitary gland. RESULT: There was no evidence of abnormal hypointense signal in the hypothalamus or pituitary gland in the patients studied, regardless of the presence of growth retardation. CONCLUSION: There was no apparent characteristic MRI appearances of iron deposition in the hypothalamus or pituitary gland in thalassaemic children with high serum ferritin.

Adolescent↗
PubMed1998

Normal fetal thyroid volume.

A prospective study of 289 normal fetal thyroids was undertaken between 20 and 36 weeks of gestation in 289 mothers without any history of thyroid disease or maternal disease that could cause intrauterine growth restriction. The fetal thyroid volume was calculated by the ellipsoid equation, with the assumption that each lobe was an ellipse. A nomogram relating fetal thyroid volume to gestational age was established. The mean fetal thyroid volume was found to be 0.23 +/- 0.18 cm3 (median 0.17 cm3; range 0.022-0.85 cm3). The ratio of fetal thyroid volume to estimated fetal weight (V/W ratio) (at 0.163 +/- 0.079 cm3/kg) was constant throughout gestation. The value was smaller than those of the child and the adult reported in other studies, indicating that fetal thyroid enlargement is likely to be underestimated if based on postnatal criteria. It was found that the mean fetal thyroid volume was significantly correlated with estimated fetal weight and gestational age, in which the former dominated the effect. The fetal thyroid increased in size much faster after 32 weeks, suggesting that evaluation of possible fetal goiter should take into account gestational age and the nomogram developed in this study.

Body Weight↗
PubMed1998

Sedation versus general anaesthesia in paediatric patients undergoing chest CT.

OBJECTIVE: CT of the chest in paediatric patients often requires sedation or general anaesthesia to minimize motion artefacts. Both sedation and general anaesthesia are associated with atelectasis which obscures the underlying pulmonary pathology. We conducted a prospective study to compare these two methods with respect to degree of motion artefacts and extent of atelectasis. MATERIAL AND METHODS: Nineteen patients undergoing 22 chest CT examinations were randomly selected for either sedation or general anaesthesia. The total area of atelectasis and the degree of motion artefacts were measured. RESULTS: The mean percentage of atelectasis was 6.67% for general anaesthesia and 0.01% for sedation (p = 0.01). There was no significant difference in the quality of the images between the sedation patients and the general anaesthesia patients. CONCLUSION: Whenever the clinical condition permits it, sedation rather than general anaesthesia should be given to paediatric patients undergoing chest CT.

Anesthesia, General↗
PubMed1998

Body fatness and serum lipids of 11-year-old Chinese children.

It has been suggested that distribution of body fat has a stronger bearing on health risk than total body fat. Magnetic resonance imaging (MRI) was used to examine the distribution of fat and correlated with body fat assessed by the usual clinical methods-weight, weight-for-height, body mass index (BMI), triceps and subscapular skinfold thickness in 11-y-old Chinese children. Lipid profiles were used as indicators for coronary risk. Eighty-eight subjects had body fat distribution estimated by MRI, while 49 had serum lipids measured. Anthropometric parameters correlated significantly with total fat at the umbilical level measured by MRI (weight: r = 0.90 in boys, 0.75 in girls; BMI: r = 0.94 in boys, 0.87 in girls; percent median weight-for-height: r = 0.90 in boys, 0.79 in girls, triceps skinfold thickness: r = 0.89 in boys, 0.90 in girls; subscapular skinfold thickness: r = 0.93 in boys, 0.88 in girls). Obese subjects had proportionally less visceral fat than subcutaneous fat at umbilical level. Using stepwise multiple regression, predictive factors for high-density lipoprotein cholesterol were BMI in boys and breast-staging in girls. For triglycerides, it was genital staging in boys and for total cholesterol, it was breast-staging in girls. Visceral fat was not a significant determinant of serum lipids.

Adipose Tissue↗
PubMed1998

Spontaneous intramural haematoma of the oesophagus: CT and MRI appearances.

A 64-year-old man with history of ischaemic heart disease and coronary artery bypass graft surgery, but no history of peptic ulcer or liver disease, presented with retrosternal pain and coffee-ground vomitus. Endoscopy revealed a long column of bluish discolouration with normal mucosa interpreted as a grade IV oesophageal varix. Computed tomography showed a non-enhancing low-density submucosal columnar lesion in the mid- and lower oesophagus consistent with a submucosal haematoma. This resolved on follow-up at 10 days. The magnetic resonance features of intermediate signal intensity on T1-weighted images and hyperintense signal on T2-weighted images of this lesion are also highlighted.

Esophageal Diseases↗
PubMed1998

Hepatic hemangioma: quantitative color power US angiography--facts and fallacies.

PURPOSE: To explore the origin of signals detected with color power ultrasound (US) angiography (CPA) and evaluate a semiquantitative method to assess signals in hepatic hemangiomas. MATERIALS AND METHODS: Twenty-four adult patients with 27 hepatic hemangiomas (< 2 cm in diameter) and five patients with five hyperechoic hepatic metastases underwent CPA and conventional color Doppler US in this prospective study. A sponge phantom was studied to determine whether the origin of CPA signals was related to architecture. The mean number of signals and the signal density in each lesion were scored. RESULTS: A "diffuse blush" was seen in all capillary hemangiomas at CPA, whereas no signal was seen at color Doppler US. The sponge phantom test produced a CPA appearance similar to that of capillary hemangiomas. Quantitative analysis of CPA images of hepatic hemangiomas showed a mean of 16.1 signals per cubic centimeter and a mean signal area of 25%. Hyperechoic avascular hepatic metastases resulted in CPA images similar to those of hepatic hemangiomas, with no quantitative difference in signal count, despite a mild qualitative difference at CPA. CONCLUSION: CPA signals in hepatic hemangiomas appear to be related more to architecture than to true capillary flow. There is a qualitative difference in the strength of the blush at CPA between hepatic hemangiomas and metastases, which may be the only possible differentiating factor.

Adult↗
PubMed1998

Cervical assessment by magnetic resonance imaging--its relationship to gestational age and interval to delivery.

The aim of this cross-sectional study was to assess the uterine cervix in late pregnancy, using MRI, and to study its relationship to the gestational age and the time interval to delivery. 91 women with a singleton cephalic presenting fetus had MRI of the pelvis between 35 and 41 weeks. All had had one prior lower segment Caesarean section and no history of prior vaginal delivery. The cervical length, internal and external os diameter, cervical signal intensity and the angulation of the cervix with the cephalocaudal axis were measured on sagittal T2 weighted images and correlated with the gestational age and the interval from the MRI examination to delivery. It was found that the signal intensity of the cervical stroma increased with the gestational age. A higher signal intensity in the cervical stroma was associated with a shorter time interval to delivery. Deliveries after 40 weeks tended to occur more commonly in those with lower signal intensity in the cervical stroma and also in those with a smaller external os diameter. It is concluded that cervical softening as assessed on MRI correlated with gestational age and the time interval to delivery.

Cervix Uteri↗
PubMed1998

Colour Doppler flow in normal axillary lymph nodes.

81 women with carcinoma of the breast who underwent axillary nodal dissection were studied pre-operatively with colour Doppler ultrasound. The presence of colour Doppler flow was demonstrated in 83.6% of normal lymph nodes compared with 87.5% of metastatic lymph nodes. Using the presence of colour Doppler signal as the sole diagnostic criterion for the diagnosis of metastasis gave a sensitivity of 92.5%, specificity of 9.52%, accuracy of 50%, positive predictive value of 49.3% and negative predictive value of 57.1%. Using grey scale sonographic criteria, where a metastatic node was defined as a node with loss of central fatty hilum and/or eccentric cortical hypertrophy, a sensitivity of 79.5%, specificity of 94.0%, accuracy of 87.6%, positive predictive value of 91.2% and negative predictive value of 85.5% were obtained. Colour Doppler studies of the axillary nodes in a second group of 106 women who attended for breast cancer screening and had no significant breast or axillary pathology also showed colour Doppler signal in 86.7% of nodes. It is concluded that colour Doppler flow signals can be demonstrated in both normal and metastatic axillary lymph nodes, and is highly non-specific when used as the sole diagnostic criterion in the diagnosis of malignancy.

Axilla↗
PubMed1998

Percutaneous biopsy of small hepatic lesions using an 18 gauge automated needle.

This study evaluates the efficacy of ultrasound guided percutaneous biopsy using an 18 gauge automated side-cutting needle in the diagnosis of small (< or = 3 cm) focal hepatic lesions. 137 consecutive percutaneous biopsies of 131 different small (< or = 3 cm) focal hepatic lesions were included. 11 biopsies were performed on lesions of < or = 1 cm in diameter, 56 were on lesions 1.1-2 cm in size and 70 on lesions 2.1-3 cm in size (average 2.3 +/- 0.7 cm; median 2.3 cm; range 0.7-3 cm). The biopsy specimen was sufficient for diagnosis in 135 cases (98.5%). The sensitivity for diagnosing malignancy was 96.4%; specificity was 100%, positive and negative predictive values were 100% and 94.6%, respectively; accuracy was 97.8%. There was no statistically significant difference in the diagnostic efficacy for lesions of different pathology and size. No significant post-biopsy complication occurred. It is concluded that the 18 gauge Temno needle is safe and effective in diagnosing small hepatic lesions.

Adolescent↗