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R A Coulden

Publications and source records attributed to R A Coulden.

At least 19 recordsLinked to original sources
PubMed2004

Semi-quantitative assessment of tricuspid regurgitation on contrast-enhanced multidetector CT.

AIM: To assess whether the early regurgitation of intravenous contrast medium into the inferior vena cava (IVC) and/or hepatic veins on computed tomography (CT), indicates tricuspid regurgitation (TR), and if so, whether it be used to grade severity. MATERIALS AND METHODS: We identified 86 consecutive patients that had been investigated for possible pulmonary endarterectomy at Papworth Hospital. From these, 61 patients were selected in whom CT, transthoracic echocardiography, and right heart catheterization (RHC) had been performed within 6 weeks. Using an arbitrary visual scale, the degree of TR assessed by intravenous contrast-enhanced CT was compared with echocardiography. Results were analysed using a kappa weighted statistical test. In addition, CT and echocardiographic assessments of TR severity were correlated with pulmonary artery pressure measurements obtained by RHC (Spearman's rank correlation coefficient). RESULTS: CT assessment of TR had a sensitivity of 90.4% and a specificity of 100% in detecting echocardiographic TR. For TR graded as more than trivial by echocardiography, sensitivity of CT was 100%. With respect to RHC data, the correlation between severity assessment of TR between CT and echocardiography using the Kappa weighted coefficient was 0.56 (moderately good agreement). With respect to RHC data, the correlation between mean pulmonary pressure and TR grading on CT and echocardiography was r = 0.685 (p < 0.001) and r = 0.727 (p < 0.001), respectively. CONCLUSION: Early opacification of the IVC or hepatic veins on first-pass contrast-enhanced CT almost invariably indicates TR. There is moderately good agreement between CT and echocardiographic assessment of the severity of TR. Both CT and echocardiographic grading of TR correlate well with RHC measurements of pulmonary artery pressure.

Adolescent↗
PubMed2001

Airway complications after lung transplantation: treatment and long-term outcome.

BACKGROUND: Airway complications are a significant cause of morbidity after lung transplantation. Effective treatment reduces the impact of these complications. METHODS: Data from 123 lung (99 single, 24 bilateral) transplants were reviewed. Potential risk factors for airway complications were analyzed. Stenoses were treated with expanding metal (Gianturco) stents. RESULTS: Mean follow-up was 749 days. Thirty-five complications developed in 28 recipients (complication rate: 23.8%/anastomosis). Mean time to diagnosis was 47 days. Only Aspergillus infection and airway necrosis were significantly associated with development of complications (p < 0.00001 and p < 0.03, respectively). Stenosis was diagnosed an average of 42 days posttransplant. Average decline in forced expiratory volume in 1 second (FEV1) was 39%. Eighteen patients (13 single and 5 bilateral) required stent insertion. Mean increase in FEV1 poststenting was 87%. Two stent patients died from infectious complications. Six patients required further intervention. Long-term survival and FEV1 did not differ from nonstented patients. CONCLUSIONS: Aspergillus and airway necrosis are associated with the development of airway complications. Expanding metal stents are an effective long-term treatment.

Bronchial Diseases↗
PubMed2001

The role of preliminary interpretation of chest radiographs by radiographers in the management of acute medical problems within a cardiothoracic centre.

Radiographic staff in a regional cardiothoracic centre were asked to assess all pre- and post-operative chest radiographs over a 6-month period. Radiographs showing new, acute changes were noted and a red dot placed on the film. Medical staff were notified of radiographs with red dots, and these were subsequently reported by radiologists. Using reports by radiologists as the gold standard, an audit was performed of the radiographers' accuracy in identifying new abnormalities. The absence of a necessary red dot as well as inappropriate use were noted. To enhance the accuracy of radiograph interpretation, a series of lectures on the chest radiograph and a protocol for red dot use were developed by senior radiologists. During this 6-month period 8614 chest radiographs were taken; red dots were applied to 464 (5%). These red dots were considered incorrect in 100 radiographs. Radiographers misinterpreted or missed potentially important changes in 38 of the remaining 8150 radiographs without red dots (sensitivity and specificity of 90% and 99%, respectively). Radiographers appeared to err on the side of caution when confronted with an abnormal chest radiograph, especially when previous radiographs and reports were unavailable. This resulted is a relatively high false positive rate. Future audits will show whether this rate can be reduced by continued training. Subtle interpretation is crucial to distinguish between an abnormal chest radiograph needing urgent medical attention and an abnormal chest radiograph with normal post-operative changes. The opinion of the experienced and trained radiographer is immediate and may be invaluable to the diagnostic care of the patient.

Acute Disease↗
PubMed2000

Aorto-atrial fistula after operated type A dissection.

The development of a fistula between the aorta and right atrium is a rare complication of ascending aortic dissection and has a high mortality if not diagnosed and surgically treated. Clinical diagnosis is best supported by specialised imaging. In addition it may present technically very challenging problems. We report the first case which follows aortic root replacement for an acute type A dissection. Aorto-right atrial fistula (AoRAF) rarely complicates ascending aortic dissection. We report the first case to follow corrective surgery for aortic dissection.

Aortic Dissection↗
PubMed2000

Complete pathological response to chemotherapy for non-small cell lung cancer demonstrated by gamma camera positron emission tomography.

We report the case history of a 61-year-old female smoker who presented with an inoperable T2N2M0 squamous cell carcinoma of the right upper lobe bronchus. This was staged by computed tomography (CT), positron emission tomography (PET) using a modified dual-headed gamma camera, and mediastinoscopy. She then underwent three cycles of cisplatin-containing chemotherapy. After the chemotherapy, CT demonstrated a residual 10 mm mass in the right upper lobe and a considerable reduction in size of the mediastinal lymphadenopathy. Functional tumour imaging with PET showed no abnormality, suggesting that there was no remaining viable tumour. At right upper lobectomy a complete pathological response was confirmed. We discuss PET, the potential new applications of gamma camera technology, and the use of cisplatin-containing chemotherapy in non-small cell lung cancer.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2000

High resolution magnetic resonance imaging of atherosclerosis and the response to balloon angioplasty.

OBJECTIVE: To explore the use of high resolution magnetic resonance imaging (MRI) of the popliteal artery in defining atheroscelerotic lesions and to monitor the remodelling response to balloon angioplasty. METHODS: Four patients (aged 49-67) with symptomatic discrete popliteal artery stenoses, as demonstrated by conventional angiography, underwent balloon angioplasty. MRI of the diseased vessel was performed before and one week, one month, three months, and six months after therapeutic balloon angioplasty. Cine phase contrast MRI was used to estimate blood flow just proximal to the lesion before and after angioplasty. RESULTS: In all patients the extent of the atherosclerotic plaque could be defined, such that even in segments of vessel which were angiographically "normal", atherosclerotic lesions with cross sectional areas ranging from 49% to 76% of potential lumen area were identified. Following angioplasty, plaque fissuring and local dissection were easily identified and serial changes in lumen diameter, blood flow. and lesion size could be documented. CONCLUSIONS: High resolution MRI can define the extent of atherosclerotic plaque in the peripheral vasculature and demonstrate the changes that occur with remodelling and restenosis following angioplasty. As a safe, reproducible technique MRI is ideal for assessing plaque and monitoring intervention, but further technological developments will be needed if similar or better images are to be achieved in other vascular beds.

Aged↗
PubMed2000

An investigation into causative factors in patients with bronchiectasis.

Bronchiectasis is a pathologic description of lung damage characterized by inflamed and dilated thick-walled bronchi. These findings may result from a number of possible causes and these may influence treatment and prognosis. The aim of this study was to determine causative factors in 150 adults with bronchiectasis (56 male, 94 female) identified using high-resolution computerized tomography. Relevant factors were identified in the clinical history; cystic fibrosis gene mutation analysis was performed; humoral immune defects were determined by measuring immunoglobulins, IgG subclasses and functional response to Pneumovax II vaccine; assessment was made of neutrophil function (respiratory burst, adhesion molecule expression, and chemotaxis); ciliary function was observed and those likely to have allergic bronchopulmonary aspergillosis (ABPA) were identified. Causes identified were: immune defects (12 cases), cystic fibrosis (4), Young's syndrome (5), ciliary dysfunction (3), aspiration (6), panbronchiolitis (1), congenital defect (1), ABPA (11), rheumatoid arthritis (4), and early childhood pneumonia, pertussis, or measles (44). Intensive investigation of this population of patients with bronchiectasis led to identification of one or more causative factor in 47% of cases. In 22 patients (15%), the cause identified had implications for prognosis and treatment.

Adolescent↗
PubMed2000

Impact of motion artefact on the measurement of coronary calcium score.

Reports have shown that total coronary calcium (CC) measured by electron beam CT (EBCT) correlates well with atheroma extent, and this in turn is a reliable indicator of risk for future ischaemic events. Although total CC may be measured using a conventional CT scanner, image quality is degraded by cardiac motion artefact. Errors in CC measurement owing to slice misregistration between adjacent breath-holds affect both conventional CT and EBCT. The latest generation conventional CT scanners have acquisition times of 500 ms or shorter, and, when combined with ECG triggering, quantitative CC measurement without reliance upon EBCT becomes a real possibility. We investigated the effect of motion on the measured calcium score using a moving phantom. Our results show that use of ECG triggering with conventional CT improves reproducibility of Agatston calcium score measurement. Increasing motion time during image acquisition results in an apparent increase in the Agatston CC score. Alternative measures of the amount of CC may be less susceptible to motion-induced bias, but have a similar reproducibility.

Algorithms↗
PubMed1996

Fast CT for aortic dissection.

Results were evaluated in 81 patients with suspected acute aortic dissection who were examined on a fast CT system capable of a 1 s data acquisition time. 17 patients had Type A and nine had Type B dissections. Radiological assessment provided 78 confident reports and expressed some uncertainty about the diagnosis in three patients. Overall sensitivity for aortic dissection was 96.2% and specificity was 96.4%. When 78 confident reports alone were considered, both sensitivity and specificity reached 100%. Reconstruction of data at 100 ms intervals allowed discrimination between artefacts in the ascending aorta and Type A dissections. CT can often be used as the single investigation prior to surgery for acute Type A dissections.

Acute Disease↗
PubMed1993

Coronary angiography: an analysis of radiographic practice in the UK.

There is growing public and professional concern over the risks of medical ionizing radiation. It is therefore important to examine our procedures for ways in which we can reduce radiation dose to patients and staff. We surveyed 48 catheter laboratories nationwide to establish the range of practice in performing "routine" coronary angiography and left ventriculography. There were wide variations in the numbers of views obtained, mean ciné film lengths and mean fluoroscopy times. Despite the recommendation of the National Radiological Protection Board, only five of the 36 centres responding were able to provide estimates of patient radiation dose per procedure. Calculations of maximum and minimum patient doses, based on ciné film length and fluoroscopy time, show a fourfold variation between hospitals. Using the concept of estimated dose equivalent, the predicted lifetime fatal cancer risk for a routine examination ranges from 1/16,600 to 1/4300. As a preliminary step in radiation dose reduction we have used this survey data to suggest how a typical coronary angiogram and left ventriculogram might be performed.

Coronary Angiography↗
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↗
PubMed1991

Magnetic resonance imaging: when is one sequence sufficient?

We have studied 100 patients undergoing magnetic resonance imaging (MRI) in eight well-defined clinical problems. The relative values of the clinical details and the initial imaging sequence in reaching the final MR diagnoses were assessed. For each patient, two radiologists independently predicted the likely radiological findings from the clinical details. They then assessed the radiological appearances shown by the initial imaging sequence (which was chosen according to the clinical problem). Lastly, they made a final interpretation using all the available information. Prediction of likely radiological abnormalities from the clinical details proved unreliable. However, the radiological assessment of the initial imaging sequence was reliable for clinical problems related to the pituitary fossa, posterior fossa, internal auditory meatus and for suspected multiple sclerosis. In these patient groups additional sequences might be reserved for those with equivocal findings. Conversely, assessment of the initial imaging sequence proved unreliable compared with the full radiological assessment for clinical problems in the lumbar spine, the axilla and the knee. This study has led us to reduce the number of sequences performed for some clinical problems, with a commensurate increase in the throughput of patients.

Clinical Competence↗
PubMed1990

Preliminary report: hepatic vein Doppler in the early diagnosis of acute liver transplant rejection.

37 transplanted livers (in thirty patients) were assessed by serial doppler ultrasound examination. 18 of 23 biopsy-proved rejection episodes were associated with abrupt damping of the normally pulsatile blood flow of the hepatic veins. In the other 5 episodes, the waveforms were damped at the outset by perioperative ischaemia. There were no rejection episodes with normal traces. Another cause of damping was cholangitis (5 episodes), but this was distinguishable clinically and biochemically. There were no episodes of rejection with normal hepatic vein traces. Serial doppler examination, in combination with clinical evaluation, may allow earlier diagnosis and treatment of liver rejection.

Acute Disease↗
PubMed1990

The use of duplex Doppler ultrasound in the diagnosis of breast cancer.

Duplex Doppler ultrasound was used to examine 50 breast lesions in 45 patients. Examination was confined to the region of interest, which in most cases was a palpable lump, and the corresponding area of the contralateral breast as a control. In only one patient was a Doppler signal obtained from a normal breast. Nine of the 50 lesions were believed to represent simple breast cysts at sonography and were not treated further. The remaining 41 lesions were excised; 22 were carcinomas and 19 benign (fibrocystic disease 7, fibroadenomas 5, miscellaneous 7). Doppler signals were obtained in 20 of the carcinomas and three of the benign lesions. In this series, the sensitivity of duplex Doppler ultrasound for the detection of breast carcinoma was 91%, and the specificity 89%. The positive predictive value was 87% and the negative predictive value 93%.

Adult↗
PubMed1990

Ultrasound cystography in the diagnosis of vesicoureteric reflux.

Vesicoureteric reflux is common in children with urinary tract infection and may cause end-stage renal failure. The diagnosis is usually based on micturating cystourethrography (MCU). We describe an alternative technique using ultrasound during bladder infusion with agitated saline. Comparison of the 2 methods shows ultrasound to be 100% sensitive in the detection of grades 3 and 4 reflux. Conclusive evidence of reflux was seen in 2 cases where MCU was subsequently normal, questioning the role of MCU as the gold standard.

Adolescent↗