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D J Lomas

Publications and source records attributed to D J Lomas.

49 records · Page 3Linked to original sources
PubMed1993

Radiologically-guided cutting needle biopsy for suspected malignancy in childhood.

Twenty-seven cutting needle biopsies were performed on 25 children with suspected malignancy using computed tomographic (CT, 22) or ultrasound (US, 5) guidance. Anatomical sites were: retroperitoneum 6, liver 4, kidney 4, abdomen/pelvis 4, thorax 4, bowel 2, neck 1. Sixteen patients (64%) underwent subsequent open biopsy (5), marrow biopsy (2) or resection (9). There was complete concordance between the histological findings from the open or marrow biopsy and the previous needle biopsy in 12 of these 16 patients; in two patients the needle biopsy was misleading, causing inappropriate initial treatment in one. In two other patients needle biopsy was correct but lacked specific diagnostic features. Needle biopsies were performed under general, local or Ketamine anaesthesia. There were no apparent complications related to these procedures. We believe that radiologically-guided cutting needle biopsy should replace open biopsy in most children with solid malignant lesions. It can easily be performed during a single anaesthetic episode which allows radiological evaluation, biopsy, bone marrow and cerebrospinal fluid sampling. However, the potential for sampling error and histological variation within these tumours needs to be borne in mind.

Adolescent↗
PubMed1993

Computed tomography or magnetic resonance imaging for axillary symptoms following treatment of breast carcinoma? A randomized trial.

Fifty-eight patients presenting with axillary symptoms (pain, oedema, etc) following radiation therapy for breast carcinoma were randomized to be investigated by either computed tomography (CT: 29 patients) or magnetic resonance imaging (MRI: 28). The objectives of the study were to compare the efficacy of the two tests in identifying the presence of tumour and their effectiveness as judged by quality of life (QOL) outcome measurements. Both tests proved efficacious; the predictive values for a positive result (tumour present) were 100% for both tests; the predictive values for negative findings were in the range of 76 to 90% for CT and 81 to 100% for MRI. As regards outcome, complete QOL data were available in 37 patients (17 of these patients had CT, 20 MRI). Although the mean change in QOL over 6 months was slightly more favourable in the patients investigated by MRI than in the CT group, the difference did not reach statistical significance.

Aged↗
PubMed1993

Duplex Doppler measurements of the portal vein in portal hypertension.

In order to assess the validity of quantitative duplex Doppler measurements of portal vein flow, 10 patients with proven diffuse liver disease and portal hypertension were examined serially by two independent observers over a 3 month period. Multiple measurements of the portal vein were made using a consistent technique in an attempt to minimize observer errors. One patient proved unsuitable for ultrasound examination. In the remaining nine patients the intra-observer portal vein measurements for one observer (19 paired examinations) correlated significantly for flow velocity (r = 0.80, P < 0.001) and derived bulk flow (r = 0.54, P < 0.02) but not for cross-sectional area (r = 0.27, P > 0.05). The intra-observer measurements for the second observer (11 paired examinations) were significantly correlated for cross-sectional area (r = 0.64, P < 0.05) and derived bulk flow (r = 0.61, P < 0.05) but not for flow velocity (r = 0.5, P > 0.05). The inter-observer measurements (28 paired examinations) of the portal vein were all highly significantly correlated for cross-sectional area (r = 0.63, P < 0.001), flow velocity (r = 0.79, P < 0.001) and derived bulk flow (r = 0.73, P < 0.001). These results suggest that this quantitative Doppler technique may be valid for the serial study of portal vein flow in selected groups of patients with diffuse liver disease and portal hypertension.

Adult↗
PubMed1993

Magnetic resonance imaging of the knee: does foot restraint improve the examination?

Involuntary movement by the patient can cause severe artefacts in magnetic resonance imaging of the knee. We have designed and constructed a device that immobilizes the foot, and thereby the knee. In this way the knee still remains accessible for the application of a variety of surface coils. A retrospective subjective analysis was performed of the magnetic resonance images from a control group of 23 patients who were examined without the restraint device and a study group of 26 patients in whom the device was used. The differences in the central tendency of subjective scores between the control and study groups were not significant for either motion artefact or anatomical conspicuity. However, in terms of dispersion the observed reduction in the study group was significant for anatomical conspicuity (p < 0.05) and almost significant for motion artefact (p < 0.10). These findings suggest that the restraint device may improve image quality by eliminating some of the worst motion artefacts. The device also significantly improves positioning of the knee in relation to the magnet isocentre (p < 0.01).

Adolescent↗
PubMed1993

The sonographic appearances of pleural fluid.

In order to document the sonographic changes of pleural fluid the appearances of 93 presumed pleural fluid collections in 89 patients were recorded. In all patients the clinical or radiographic appearances were atypical and they were referred for guided aspiration or drainage of suspected pleural fluid. Ultrasound guided aspiration was successful in 90 collections in 86 patients. It was unsuccessful in three "collections" subsequently shown or presumed to be of a solid nature. In nine of the proven fluid collections an earlier attempt at blind aspiration had been unsuccessful. 54 (60%) of the proven fluid collections had a characteristic sonographic appearance of pleural fluid as an anechoic space unrestricted within the pleura. Of the remaining 36 collections, 16 had diffuse internal echoes, 12 were confined to one area of the pleural space (primary loculation) and 13 had internal septa (secondary loculation). Dynamic signs were demonstrated in 75 (83%) of the collections as flapping movements of atelectatic lung (51), of internal septa (12), or of debris attached to the wall of the collection (25). Three (4%) of fluid collections had sonographic features indistinguishable from those of solid pleural lesions, indicating that in a small percentage of cases sonography will not reliably distinguish between solid and fluid in the pleural space.

Adolescent↗
PubMed1992

Doppler ultrasound of the hepatic veins: normal appearances.

Doppler ultrasound of the hepatic veins gives a pulsatile velocity profile which mirrors the cardiac cycle. We describe the physiological basis for the complex waveform and suggest a venous pulsatility index (VPI) which can be used to quantify it. We have studied normal volunteers under differing conditions to establish a normal range of VPI. This provides a baseline against which abnormal patterns of hepatic vein Doppler can be judged.

Adolescent↗
PubMed1992

The role of hepatic vein Doppler in diagnosing acute rejection following paediatric liver transplantation.

Serial Doppler ultrasound examinations of the hepatic veins were performed on 50 consecutive paediatric liver transplants. Damping of the normally pulsatile signal was observed in 23 of the 32 biopsy-proven episodes of rejection. In 10 episodes, the reduction in hepatic vein pulsatility preceded clinical and biochemical evidence of rejection by up to 36 h. Seven cases had damped signals throughout the post-operative period which precluded assessment by this method. In two patients the hepatic vein signals remained pulsatile despite rejection, one patient having unsuspected tricuspid regurgitation, and the other a stenotic IVC anastomosis. In the 35 liver transplants with normal pulsatility, hepatic vein Doppler proved to be a valuable indicator of acute rejection during the first 2 weeks following transplantation (sensitivity 92%, specificity 100%, positive predictive value 100% and negative predictive value 83%).

Adolescent↗
PubMed1992

CT-guided drainage of pelvic abscesses: the peranal transrectal approach.

Five patients with deep pelvic abscesses underwent computed tomography (CT)-guided catheter drainage using a transrectal approach. The use of an outer removable plastic sheath over the catheter to facilitate positioning and prevent inadvertent damage to the mucosal wall is described. This new approach using CT guidance is discussed and the alternative routes reviewed.

Abscess↗
PubMed1992

Duplex Doppler ultrasound for the detection of vascular occlusion following liver transplantation in children.

Sixty-three children and adolescent patients who received 78 consecutive orthotopic liver transplants and had serial duplex ultrasound monitoring were retrospectively reviewed for episodes of occlusion of the hepatic artery or portal vein. There were 13 documented episodes of complete occlusion of the main hepatic artery or a major branch, of which nine were diagnosed by the absence of flow during duplex ultrasound examination. Four occlusions were not detected, two affected hepatic artery branches, one an accessory hepatic artery, and one the main hepatic artery. The overall sensitivity of the method was 69% and specificity 100%. Six portal vein occlusions were documented in five patients and all six were successfully diagnosed on ultrasound examination, giving a sensitivity and specificity of 100%. Three of the patients had simultaneous occlusions of both vessels. In the early post-operative period duplex Doppler ultrasound examination has proved an effective non-invasive method for the detection of vascular occlusion, but is not yet sensitive enough to replace angiography fully for the detection of hepatic artery occlusion, particularly when this occurs distal to the main hepatic artery.

Adolescent↗
PubMed1991

Measurement of regional left ventricular function using labelled magnetic resonance imaging.

A technique for assessing regional left ventricular function using magnetic resonance imaging is described. Spatial modulation of magnetization (SPAMM) is effected immediately before images are obtained at various intervals during the cardiac cycle using a modified field echo even rephasing technique (FEER). By performing such modulation in two planes, a grid pattern of labelling can be produced across the image. On the resulting labelled short axis images of the left ventricle, the systolic increase in thickness (thickening) and decrease in length (shortening) of different regions of myocardium can then be measured. The findings in five normal volunteers are presented. Radial shortening was twice as great in the endocardium (mean 20.4%, standard deviation (SD) 5.7) than in the epicardium (mean 10.2%, SD 5.5) and appears to offer more promise as a marker of regional function than simple thickening (mean 9.8%, SD 13.6).

Adult↗
PubMed1990

Powered cutting needle biopsy of the pleura and chest wall.

Over a 24 month period, 35 patients seen consecutively with a pleural or chest wall mass had a percutaneous biopsy using an 18 gauge cutting needle operated by a specially designed, hand held, spring loaded trigger system (Biopty TM, Biopsy instrument, Radiplast A.B. Sweden). Biopsies were performed under local anaesthesia with ultrasound, fluoroscopic, or computed tomography guidance, depending on the site and nature of the lesion. An excellent specimen, consisting of a core of tissue, was consistently obtained and a specific histological diagnosis was possible in 30 patients (28 malignant lesions and two benign lesions). In two patients there was an unequivocal diagnosis of malignancy but the tumour was too necrotic to allow a cell type to be established. In three patients the specimen consisted predominantly of dense fibrous tissue. One of these was a presumed false negative result for malignancy; the other two are presumed true negative results. There were no complications of the procedure.

Biopsy, Needle↗
PubMedDate not supplied

CT demonstration of acute and chronic iliofemoral thrombosis.

A case of bilateral iliofemoral vein thrombosis in a young man, secondary to testicular seminoma, is presented. Both the acute and chronic thrombus were detectable on abdominopelvic CT without contrast enhancement, and the mechanisms responsible for the differing appearances of the thrombi are discussed. Detection of thrombi in this way may avoid the administration of contrast medium.

Adult↗