The clinical impact of high resolution computed tomography in patients with respiratory disease.

OBJECTIVE: High resolution computed tomography is widely used to investigate patients with suspected diffuse lung disease. Numerous studies have assessed the diagnostic performance of this investigation, but the diagnostic and therapeutic impacts have received little attention. METHODS: The diagnostic and therapeutic impacts of high resolution computed tomography in routine clinical practice were evaluated prospectively. All 507 referrals for high-resolution computed tomography over 12 months in two centres were included. Requesting clinicians completed questionnaires before and after the investigation detailing clinical indications, working diagnoses, confidence level in each diagnosis, planned investigations and treatments. RESULTS: Three hundred and fifty-four studies on 347 patients had complete data and were available for analysis. Following high-resolution computed tomography, a new leading diagnosis (the diagnosis with the highest confidence level) emerged in 204 (58%) studies; in 166 (47%) studies the new leading diagnosis was not in the original differential diagnosis. Mean confidence in the leading diagnosis increased from 6.7 to 8.5 out of 10 (p < 0.001). The invasiveness of planned investigations increased in 23 (7%) studies and decreased in 124 (35%) studies. The treatment plan was modified after 319 (90%) studies. CONCLUSIONS: Thoracic high-resolution computed tomography alters leading diagnosis, increases diagnostic confidence, and frequently changes investigation and management plans.

Subintimal angioplasty for femoro-popliteal occlusive disease.

There has been a longstanding debate about the roles of surgical bypass graft, percutaneous transluminal angioplasty, subintimal angioplasty, and conservative management for femoro-popliteal occlusive disease. Subintimal angioplasty was first described in 1987 as a method of performing an endovascular arterial bypass. The subintimal space at the start of the occlusion is entered with a catheter and a wire loop is used to cross the occlusion and reenter the vessel lumen distally. In patients with critical limb ischemia, there is high quality evidence demonstrating that the limb salvage rate and amputation-free survival rates for surgery and endovascular treatment are similar, but surgery is more expensive than angioplasty in the short term. In patients with intermittent claudication, surgical bypass using an autologous saphenous vein graft is currently believed to be the gold standard, but this is increasingly questioned in the light of recent advances in endovascular techniques. Surgical bypass with vein graft offers a 2-year patency of 81%, compared with 67% for a polytetrafluoroethylene (PTFE) graft and at best 67% for subintimal angioplasty. The better patency offered by surgery must be balanced against a higher morbidity and mortality. To conclude, subintimal angioplasty is an extremely valuable technique in the management of critical limb ischemia. Based on the evidence to date, this technique is likely to have an increasing role in the management of intermittent claudication over the coming years, particularly if the risk of general anaesthesia is high or there is no suitable vein.

High definition three-dimensional ultrasound to localise the tumour bed: a breast radiotherapy planning study.

BACKGROUND AND PURPOSE: Complex radiation techniques, such as conformal radiotherapy for partial breast irradiation, require accurate localisation of the tumour bed. This study investigated high definition 3D ultrasound for breast tumour bed localisation. Study aims were: firstly, to determine how easily a tumour cavity could be visualised with 3D ultrasound; secondly, to determine the accuracy of computed tomography (CT) and 3D ultrasound co-registration; thirdly, to compare 3D ultrasound with other methods of localisation. MATERIALS AND METHODS: 3D ultrasound examinations were carried out in 40 women attending for breast radiotherapy. 3D position data were co-registered with the radiotherapy planning CT. 2D ultrasound and CT, surgical clips and CT, and CT alone were also used to localise the tumour bed in 32/40, 14/40 and 5/40 patients, respectively. Tumour bed volume and centre of gravity measurements for all methods of localisation were compared. RESULTS: Mean surgery to imaging interval was 44 days (range 23-86 days). The post-operative cavity was seen in all cases using the 3D ultrasound, and was graded as highly visible, visible and subtle in 21/40 (53%), 12/40 (30%) and 7/40 (17%) cases, respectively. There was a statistically significant improvement in the ability of 3D ultrasound to localise the tumour bed compared with 2D ultrasound. CT-ultrasound registration was achieved in all cases. Two-dimensional and 3D ultrasound showed smaller tumour bed volumes than clips. CONCLUSIONS: Three-dimensional ultrasound localisation of the tumour bed appears superior to 2D ultrasound. It can also be co-registered with a planning CT, thus allowing additional information on the size and location of the tumour bed to be integrated into complex radiotherapy planning.

Testicular calcification and microlithiasis: association with primary intra-testicular malignancy in 3,477 patients.

The prevalence of all forms of scrotal and testicular calcification and their association with testicular tumour in a symptomatic paediatric and adult population was investigated. A retrospective study of all testicular ultrasound examinations performed at a single centre over a 5-year period was undertaken. All studies were performed by experienced operators, recorded in a standard method, using high-frequency linear array transducers (> or =10 MHz). All available images (95.2%) were reviewed by experienced operators, recording the location and type of scrotal and testicular calcification according to a pre-determined schedule. A total of 3,854 studies were reviewed on 3,477 patients (age range: 1 month to 91 years). In the adult group, 3,279 examinations were analysed. Prevalence of testicular microlithiasis (TM) was 2.0%, and the prevalence of other non-microlithiasis testicular calcification (non-TM calcification) was 1.7%. Testicular tumour was associated with TM (odds ratio 9.5, P<0.001) and non-TM calcification (odds ratio 11.4, P<0.001) but not with other types of scrotal calcification. A total of 198 paediatric examinations were analysed. Prevalence of TM was 2.0% and the prevalence of non-TM calcification was 0.5%. One tumour (lymphoma) was identified, with no associated calcification. This study confirms the reported association between TM and testicular tumour and finds a previously unreported association between non-TM calcification and testicular tumour.

Is sonographically demonstrated mild distal ureteric dilatation predictive of vesicoureteric reflux as seen on micturating cystourethrography?

BACKGROUND: In most paediatric units, the micturating cystourethrogram (MCU) is the gold standard in the diagnosis of vesicoureteric reflux (VUR). Because of the well-known difficulties associated with MCUs, there is interest in any imaging finding which may be predictive of the absence of VUR with enough confidence to avoid the necessity for an MCU. OBJECTIVE: To evaluate whether incorporation of measurement of the internal diameter of the retrovesical ureter into a routine urinary tract US protocol can provide a useful predictor of VUR. MATERIALS AND METHODS: The radiology information system at the Royal Alexandra Children's Hospital in Brighton was searched to identify children who had urinary tract US and an MCU within 3 months of each other. This identified 285 renal units in 144 patients. The presence and grade of VUR on the MCU was then compared with the presence or absence of mild-to-moderate distal ureteric dilation, using 3.5 mm as the upppr limit of normal for the retrovesical ureter on US. RESULTS: A distal ureteric diameter of more than 3.5 mm on US is predictive of VUR with a sensitivity of 0.63 and specificity of 0.78. Figures for dilating VUR (grades 3-5) were 0.78 and 0.77, respectively. The negative predictive value of a ureteric calibre less than 3.5 mm in excluding dilating reflux was 0.96. Interestingly, all three solitary renal units had ureteric diameters of more than 3.5 mm but no VUR. CONCLUSIONS: Absence of distal ureteric dilation on US, on its own, cannot reliably exclude VUR. It does, however, make dilating reflux unlikely. We believe US measurement of the distal ureteric diameter is a useful additional tool in everyday assessment of children who might have reflux.