CT of the musculoskeletal system: what is left is the days of MRI?

Magnetic resonance imaging (MRI) plays a central role in the modern imaging of musculoskeletal disorders, due to its ability to produce multiplanar images and characterise soft tissues accurately. However, computed tomography (CT) still has an important role to play, not merely as an alternative to MRI, but as being the preferred imaging investigation in some situations. This article briefly reviews the history of CT technology, the technical factors involved and a number of current applications, as well as looking at future areas where CT may be employed. The advent of ever-increasing numbers of rows of detectors has opened up more possible uses for CT technology. However, diagnostic images may be obtained from CT systems with four rows of detectors or more, and their ability to produce near isotropic voxels and therefore multiplanar reformats.

MR imaging of the wrist: effect on clinical diagnosis and patient care

PURPOSE

To evaluate the effect of magnetic resonance (MR) imaging of the wrist on clinicians' diagnoses, diagnostic certainty, and patient care.

MATERIALS AND METHODS

A controlled observational study was performed. Referring clinicians completed questionnaires about diagnosis and intended management before and after wrist MR imaging. One hundred eighteen consecutive patients referred for MR imaging of the wrist were recruited from the MR imaging units at a regional teaching hospital and a large district general hospital. The main measures were changes in the clinicians' leading and subsidiary diagnoses after MR imaging, their certainty in these diagnoses, and changes in intended patient care.

RESULTS

Questionnaires were incorrectly completed for five patients, questionnaires were not returned for three, appointments were canceled for 10, and two could not tolerate the MR examination. Complete follow-up data were available for 98 patients. The clinical diagnosis changed in 55 of 98 patients; in the remaining 43 patients, diagnostic certainty increased in 23. Clinicians reported that MR imaging had substantially improved their understanding of the disease in 67 of 98 patients. The care plan changed in 45 of 98 patients, with a shift away from surgical treatment. Twenty-eight patients were discharged without further investigation. MR imaging was similarly effective in the regional teaching center and the district general hospital.

CONCLUSION

MR imaging of the wrist influences clinicians' diagnoses and management plans.

Magnetic resonance imaging of the wrist: diagnostic performance statistics

AIM

To review the published diagnostic performance statistics for magnetic resonance imaging (MRI) of the wrist for tears of the triangular fibrocartilage complex, the intrinsic carpal ligaments, and for osteonecrosis of the carpal bones.

MATERIALS AND METHODS

We used Medline and Embase to search the English language literature. Studies evaluating the diagnostic performance of MRI of the wrist in living patients with surgical confirmation of MR findings were identified.

RESULTS

We identified 11 studies reporting the diagnostic performance of MRI for tears of the triangular fibrocartilage complex for a total of 410 patients, six studies for the scapho-lunate ligament (159 patients), six studies for the luno-triquetral ligament (142 patients) and four studies (56 patients) for osteonecrosis of the carpal bones.

CONCLUSIONS

Magnetic resonance imaging is an accurate means of diagnosing tears of the triangular fibrocartilage and carpal osteonecrosis. Although MRI is highly specific for tears of the intrinsic carpal ligaments, its sensitivity is low. The diagnostic performance of MRI in the wrist is improved by using high-resolution T2* weighted 3D gradient echo sequences. Using current imaging techniques without intra-articular contrast medium, magnetic resonance imaging cannot reliably exclude tears of the intrinsic carpal ligaments. Hobby, J. L. (2001). Clinical Radiology, 56, 50-57.

An assessment of the effectiveness of magnetic resonance imaging of the shoulder: literature review

OBJECTIVE

To analyse and compare all papers published to date (August 2000) that quantify the effectiveness, defined as the impact of clinician's diagnosis or management plans, or patient outcome, of MRI of the shoulder.

DESIGN

A computerised search of Index Medicus with a broad search strategy relating to shoulder MRI was performed. Manual assessment of all papers listed was undertaken with classification of each paper depending on whether it addressed questions of (1) technical performance, (2) diagnostic performance or (3) outcome.

RESULTS

Four of 265 qualifying papers addressed aspects of effectiveness and these were reviewed. The impact on the clinician's diagnosis varied widely between papers: the primary diagnosis was altered in 23% to 68% of cases, and the management plans were subsequently changed in 15% to 61% of cases. Only one paper addressed the impact on patient health.

CONCLUSIONS

The effectiveness of MRI of the shoulder depends on the clinical skills of the referring clinician and prevalence of disease in the study population. This will have implications when the effectiveness of an imaging technique between different institutions is compared, and this in turn will influence any comparisons of cost-effectiveness.

Communication of doubt and certainty in radiological reports

We have investigated the reliability of communication of uncertainty in radiological reports. The 18 most commonly used verbal expressions of probability were identified from a series of radiological reports. 11 clinicians (three radiologists, three rheumatologists and five orthopaedic surgeons) recorded the probability that they ascribed to each of the 18 expressions using visual analogue scales. Each subject was re-tested on four occasions at least 1 week apart. The results were analysed to assess reproducibility within and between individuals. We found considerable variation in the probabilities assigned to many commonly used expressions between subjects, and between repeated testing of the same subject. Some expressions were rated much more consistently than others. "Absent", "excludes", "unlikely", "probable", "certain" and "definite" were the most consistently rated expressions. We have identified a potential source of misunderstanding in radiological reports owing to differences in interpretation of expressions used by radiologists and referring clinicians.

Incidence of vertebral fractures in the first three months after orthotopic liver transplantation

BACKGROUND AND OBJECTIVES

High rates of bone loss and increased fracture incidence have been reported in patients undergoing liver transplantation, mainly within the first post-operative year. The pathogenesis of post-transplantation bone disease has not been clearly established, but the high doses of glucocorticoids used for immunosuppression may contribute. The use of lower doses in recent years has been associated, in some studies, with lower rates of bone loss and decreased fracture incidence. The aim of this prospective study was to establish the incidence of vertebral fractures in the first 3 months in patients undergoing liver transplantation for chronic liver disease and to identify risk factors for fracture in these patients.

DESIGN AND METHODS

Thirty-seven adults with end-stage liver disease were studied prospectively prior to and 3 months after liver transplantation. Vertebral fractures were assessed semi-quantitatively from lateral spine X-rays and bone mineral density measured using dual energy X-ray absorptiometry.

RESULTS

Prior to transplantation, prevalent vertebral fractures were present in 13 patients (35%). New fractures developed after transplantation in 10 patients (27% of total) and were significantly more common in those with a prevalent vertebral fracture pre-operatively (P<0.02). Osteoporosis, defined as a bone mineral density T score below -2.5, was present in 39% of patients prior to transplantation, but bone mineral density was not helpful in predicting incident fracture, whether measured before or after transplantation. Over the 3-month study period, significant bone loss occurred in the femoral neck (P<0.05) but not the lumbar spine.

CONCLUSIONS

Our results demonstrate a high incidence of vertebral fracture in the first 3 months after liver transplantation and indicate that prevalent vertebral fracture is an important risk factor for the subsequent development of fracture in these patients. Prevention of post-transplantation bone disease should focus both on optimizing bone mass prior to transplantation and preventing bone loss in the early post-operative period.

Assessment of quantitative computed tomographic cerebral perfusion imaging with H2(15)O positron emission tomography

Assessment of quantitative cerebral blood flow on a conventional fast CT machine without the use of specialized equipment may be valuable in the investigation of acute stroke and head injury. We aimed to compare a single slice CT perfusion sequence with H2(15)O positron emission tomography using the sagittal sinus as an input function, a method that avoids unnecessary orbital irradiation. Eight patients were studied, two patients with gliomas, and six with arteriovenous malformations. The dynamic CT perfusion sequence was performed by acquiring the same 10 mm slice 10 times over 30 sec during a 50 ml bolus of intravenous contrast medium given at a rate of 7.5 ml sec-1 using a power injector. The CT perfusion studies were completed without complication. Co-registration was sub-optimal in one patient. Overall the correlation between the two methodologies was encouraging with an average r2 value of 0.524 for individual analyses. When two patients with high flow arteriovenous malformations were excluded the average r2 value increased to 0.640. The results of this CT perfusion methodology are encouraging. Having shown its feasibility, further studies in conditions with lower rates of cerebral blood flow are warranted.

Management of neck lumps--a triage model

We report our experience in the out-patient triage of 100 patients presenting with a lump in the neck. The out-patient visit consisted of a general history and examination, assessment of the upper air and food passages and, where indicated, ultrasound and core needle biopsy of the lump. Other investigations were performed as appropriate. One hundred neck lump patients were seen in a 9 month period. Ninety-six of these lumps were diagnosed on an out-patient basis, only four requiring admission for formal excision biopsy. Among the diagnoses were eleven lymphomas, nine parotid neoplasms, nine lymph node metastases, five thyroglossal cysts, and four branchial cysts. Almost half the patients seen had either a reactive lymphadenopathy, or no abnormality. The establishment of a tissue diagnosis on an out-patient basis allowed appropriate referrals to be made and management plans to be formulated. The theoretical risk of seeding of malignant cells in the needle tract is acknowledged and discussed.

Magnetic resonance imaging of the coraco-acromial ligament

The coraco-acromial ligament is important first for the stability of the shoulder joint and second because it can impinge on the rotator cuff. In this study we demonstrate how the coraco-acromial ligament can be shown by magnetic resonance imaging (MRI) in the axial plane as well as in the more conventional coronal and sagittal planes.

The use of ultrasound-guided cutting-needle biopsy in paediatric neck masses

OBJECTIVE

Neck masses are common in children. Although there is a low incidence of therapeutically significant pathology, biopsy is occasionally required for evaluation. Open biopsy or fine needle aspiration may be used to obtain tissue. Open biopsy provides material suitable for histological analysis but requires general anaesthesia. Cytological material obtained by fine needle aspiration is often inconclusive. A core of histological material may also be obtained by percutaneous cutting-needle biopsy, a recognised procedure at other anatomical sites, usually performed under local anaesthesia.

MATERIALS AND METHODS

There are few accounts using cutting needles in adult neck masses and no previous paediatric series. We present our experience of ultrasound-guided core biopsies of neck masses in 15 children ranging in age from three months to 16 years.

RESULTS

Thirteen biopsies were easily performed without sedation as an outpatient procedure under topical and injected local anaesthetic. In all fifteen cases the procedure was well tolerated and a tissue successfully obtained.

CONCLUSION

Ultrasound guided cutting needle biopsies of head and neck masses of children can be performed under local anaesthesia in the majority of cases.

MR cholangiopancreatography: prospective comparison of a breath-hold 2D projection technique with diagnostic ERCP

The aim of this study was to compare prospectively a breath-hold projection magnetic resonance cholangiopancreatography (MRCP) technique with diagnostic endoscopic retrograde cholangiopancreatography (ERCP). Seventy-six patients with suspected strictures or choledocholithiasis were referred for MRCP and subsequent ERCP examination, which were performed within 4 h of each other. The MRCP technique was performed using fat-suppressed rapid acquisition with relaxation enhancement (RARE) projection images obtained in standardised planes with additional targeted projections as required by the supervising radiologist. Two radiologists (in consensus) assessed the MRCP results prospectively and independently for the presence of bile duct calculi, strictures, non-specific biliary dilatation and pancreatic duct dilatation, and recorded a single primary diagnosis. The ERCP was assessed prospectively and independently by a single endoscopist and used as a gold standard for comparison with MRCP. Diagnostic agreement was assessed by the Kappa statistic. The MRCP technique failed in two patients and ERCP in five. In the remaining 69 referrals ERCP demonstrated normal findings in 23 cases, strictures in 19 cases, choledocholithiasis in 9 cases, non-specific biliary dilatation in 14 cases and chronic pancreatitis in 4 cases. The MRCP technique correctly demonstrated 22 of 23 normal cases, 19 strictures with one false positive (sensitivity 100 %, specificity 98 %), all 9 cases of choledocholithiasis with two false positives (sensitivity 100 %, specificity 97 %), 12 of 14 cases of non-specific biliary dilatation and only 1 of 4 cases of chronic pancreatitis. There was overall good agreement for diagnosis based on a kappa value of 0.88. Breath-hold projection MRCP can provide non-invasively comparable diagnostic information to diagnostic ERCP for suspected choledocholithiasis and biliary strictures and may allow more selective use of therapeutic ERCP.

Diagnostic and therapeutic impact of MRI and arthrography in the investigation of full-thickness rotator cuff tears

Investigation of shoulder pain is important before surgical treatment. The presence or absence of a full-thickness rotator cuff tear (FTRCT) may determine the type of surgical treatment. Both MRI and conventional arthrography can be used, but little is known about their relative diagnostic and therapeutic impact. We performed a prospective trial assessing: (a) the influence of MRI and arthrography results on the clinician's diagnostic thinking (diagnostic impact); (b) the influence of the results on the clinician's therapeutic thinking (therapeutic impact); and (c) the diagnostic performance of the two techniques in patients with surgical confirmation. A total of 104 consecutive patients with shoulder problems referred to a specialist orthopaedic shoulder clinic underwent pre-operative investigation with MRI and arthrography. The surgeon's diagnosis, diagnostic confidence and planned treatment were measured before the investigation, and then again after the results of each investigation. Before the presentation of the investigation, results, the patients were randomised into two groups. In one group MRI was presented first; in the other group, arthrography. The MRI results led to fewer changes in diagnostic category (14 of 46, 30%) than arthrography (20 of 54, 37%), but the difference was not significant (P > 0.5). Magnetic resonance imaging led to slightly more changes in planned management (17 of 47, 36%) than arthrography (14 of 55, 25%), but again the difference was not statistically significant (P > 0.3). The results of the second investigation always had less diagnostic and therapeutic impact than the first. The accuracy of MRI for FTRCT in 38 patients with surgical confirmation was 79%, sensitivity 81% and specificity 78%; the accuracy of arthrography was 82%, sensitivity 50% and specificity 96%. The clinical diagnosis and management plan can be adequately defined by a single radiological investigation. Magnetic resonance imaging and arthrography had fairly similar diagnostic and therapeutic impact and comparable accuracy, although MRI was more sensitive and less specific. Magnetic resonance imaging may be the preferred investigation because of its better demonstration of soft tissue anatomy.

Follow-up of musculoskeletal tumours. 2. Metastatic disease

Both the prognosis and the morbidity of a patient with a primary malignant musculoskeletal tumour have improved over the past 25 years due to the advent of adjuvant chemotherapy and limb-sparing surgery. This has important implications for the role of imaging at the time of initial diagnosis and during follow-up. This pictorial essay reviews the imaging and pitfalls in the interpretation of musculoskeletal sarcoma metastases using a variety of radiological techniques. The optimal imaging strategy will be stressed.

Magnetic resonance imaging or arthrography for shoulder problems: a randomised study

OBJECTIVE

Diagnostic technologies are often assessed merely by their accuracy, rather than by their impact on diagnosis and patient management. To this end the authors have undertaken a study to assess the diagnostic and therapeutic impact of magnetic resonance imaging (MRI) and arthrography of the shoulder for patients referred from a rheumatology clinic.

METHODS AND PATIENTS

Patients referred from a rheumatology clinic with symptoms warranting imaging of the shoulder were randomised to either MRI or arthrography. Data on the clinician's diagnostic confidence and management were recorded before and after imaging using questionnaires. Patients were followed-up at least 10 months after imaging to see how management plans evolved, and what proportion of patients required further imaging.

RESULTS

Fifty three shoulders underwent imaging over a year and entered into the study; 29 randomised to MRI and 24 to arthrography. Both MRI and arthrography had a similar beneficial diagnostic impact in terms of clinical diagnoses (refuted and retained) and new diagnoses established. MRI and arthrography had a similar therapeutic impact, although MRI was associated with a significant shift towards surgical intervention.

CONCLUSION

MRI and arthrography a have similar diagnostic and therapeutic impact.

The use of spiral computed tomography in musculoskeletal radiology of the lower limb: the calcaneus as an example

The advent of spiral (helical) computed tomography (CT) has markedly increased the speed of modern CT systems and has found a use in a variety of musculoskeletal applications. However, the limitations of the technique must be understood if examinations are to be tailored and optimised. This review puts the limitations and advantages into context by outlining how spiral CT can be applied to musculoskeletal imaging of the lower limb. Imaging of intra-articular fractures of the calcaneus serves as a timely example of how the imaging parameters can be optimised and where the technique can offer potential advantages over conventional CT.

Imaging of the rotator cuff: an arthrographic pitfall

We present a case where MRI and arthrography of the shoulder reports provided seemingly conflicting data. The subsequent findings at arthroscopy revealed a potential pitfall in arthrographic interpretation.

Magnetic resonance imaging or arthrography of the shoulder: which do patients prefer?

110 consecutive patients were asked about their degree of anxiety (SAI scores), pain (VAS scores) and preferences at various stages before and after imaging in order to determine whether patients with shoulder problems prefer MRI or shoulder arthrography. 88 patients underwent MRI, 42 arthrography and 19 both. Mean levels of anxiety were slightly higher for patients undergoing MRI than those having arthrography, but this difference was not statistically significant. There was a statistically significant (p < 0.03) reduction in anxiety after arthrography, but not following MRI. Pain scores fell for both patient groups while at rest during the imaging procedure compared with their pre-imaging baseline measurement. This was statistically significant (p < 0.03) for MRI, but not for arthrography. A significantly higher proportion (p < 0.001) of patients found MRI unpleasant or extremely unpleasant (20/77) compared with arthrography (3/41). Of the 25 patients who expressed a preference on the basis of past or current experience, 11 preferred MRI and 14 arthrography (NS). There was no significant difference in the proportion of patients who would not allow the test to be repeated (29/73 for MRI, 15/39 for arthrography): Although there were minor differences in both the anxiety and pain experienced by patients undergoing MRI and arthrography, this study did not reveal any firm preference for either investigation.

Non-invasive cholangio-pancreatography by breath-hold magnetic resonance imaging: preliminary results

AIMS

A preliminary comparison of a prototype breath-hold magnetic resonance cholangio-pancreatography (MRCP) technique for non-invasive imaging of the pancreatic and biliary ducts with endoscopic retrograde cholangio-pancreatography (ERCP).

METHOD

Twenty ERCP and MRCP examinations were performed in 19 patients referred for routine ERCP with suspected biliary or pancreatic abnormalities. The MRCP technique employed a modified heavily T2-weighted thick slice RARE sequence that allowed up to three images to be obtained in a 16 second breath-hold. The examinations were reported independently and the findings compared.

RESULTS

MRCP accurately discriminated between patients without obstruction (n = 12) and those with (n = 8) and correctly diagnosed the cause of obstruction (three choledocholithiasis, five malignant stricture). In the 12 patients without obstruction the examinations were concordant in eight. In the remaining four patients MRCP provided more information than the corresponding ERCP study, diagnosing a pseudocyst in one patient and visualizing the entire pancreatic duct in three patients in whom this was not possible at ERCP.

CONCLUSIONS

These preliminary results suggest that a breath-hold MRCP technique may allow the selection of those patients with obstructive lesions that require therapeutic ERCP intervention, and may have the potential to reduce the need for diagnostic ERCP examinations.

Magnetic resonance imaging of the shoulder: assessment of effectiveness

OBJECTIVES

To quantify how magnetic resonance imaging (MRI) influences clinicians' diagnosis, diagnostic confidence and management plans in patients with shoulder problems. To investigate whether such changes are associated with an improvement in health.

METHODS

A prospective observational study on all patients referred to a regional centre for MRI of the shoulder over a 6-month period. Data on diagnosis, diagnostic confidence and proposed management before MRI were compared with diagnoses and actual management after MRI. In addition, short form 36 item (SF-36) health survey data were collected at referral and again 6 months later.

RESULTS

In 86 of 99 MRI referrals there was sufficient clinical data for the patient to enter the study. MRI led to previously unsuspected diagnoses in 20 of 59 patients where the clinicians had provided full diagnostic information before and after the examination. When MRI confirmed the clinical diagnosis, significant improvements in clinicians' diagnostic confidence were found (P < 0.001). MRI led to a change in management (P < 0.05) in 44 (62%) of the 71 patients where full management plans were available. Health survey results were available in 62 patients; although there were some improvements in SF-36 scores, these did not reach statistical significance.

CONCLUSION

Magnetic resonance imaging of the shoulder significantly influences clinicians' diagnoses and management plans. However, patients do not record a statistically significant improvement in health-related quality of life over 6 months.

Leucocyte scintigraphy or computed tomography for the febrile post-operative patient?

OBJECTIVE

The optimal initial investigation for the post-operative patient with suspected occult intra-abdominal sepsis is controversial, although the diagnostic accuracy of a variety of techniques is known. Our objective is to determine which investigation has the greatest positive effect on patient management.

METHODS AND PATIENTS

We reviewed 67 consecutive post-operative patients investigated for suspected occult sepsis retrospectively and analysed the sequence of investigations required to achieve the diagnosis depending on the choice of initial investigation, and the interval between between initiating investigations and performing definitive percutaneous drainage.

RESULTS

Forty patients had scintigraphy as the initial investigation and 21 of these went on to require CT. None of the 27 patients who had CT as the initial investigation required any other imaging (chi 2 = 20.6, P < 0.0001) and appropriate percutaneous drainage was offered immediately. Conversely, the average interval to drainage in those who had scintigraphy first was 3.1 days. Fourteen out of 20 patients (70%) who had scintigraphy as the initial investigation following recent surgery, and 7 of 20 (35%) following old surgery, needed subsequent CT. None of the 20 and 7 patients in the recent and old surgery groups respectively who had CT initially required further imaging.

CONCLUSION

Our results suggest recommending CT as the initial investigation in the early post-operative period as this will reduce the total number of investigations required to achieve the diagnosis and the time to definitive drainage. In the late post-operative period, scintigraphy will resolve the majority of problems.

Vascularity of the neonatal femoral head: in vivo demonstration with power Doppler US

PURPOSE

To detect the intrinsic blood supply of the unossified neonatal femoral head in vivo by using power Doppler ultrasound (US) and to ascertain whether a reduction in blood flow could be demonstrated with hip abduction.

MATERIALS AND METHODS

One hip of 13 neonates was examined with power Doppler sonography. After vessels within the femoral head were identified, the thigh was slowly abducted and the angle at which flow became undetectable was recorded. Spectral Doppler tracings were obtained in all subjects.

RESULTS

Intrinsic blood flow of the femoral head was demonstrated in all subjects. Flow became undetectable during hip abduction in 11 of 13 neonates and reappeared during adduction. The angle at which flow became undetectable varied from 60 degrees to 85 degrees. Spectral Doppler signals demonstrated a mixed arterial and venous trace.

CONCLUSION

Power Doppler US provides a simple real-time assessment of the femoral head blood supply. This may prove helpful in identifying neonates at risk of avascular necrosis, a complication of treatment of hip dysplasia with abduction hip restraints.

Vertebral deformity in the thoracic spine in post-menopausal women: value of lumbar spine bone density

Differential bone loss in the thoracic and lumbar spine is known to occur in some patients with osteoporosis. However, the discriminant value of lumbar spine bone densitometry in the detection of thoracic spine fractures in healthy, population-based women has not been established. The relationship between lumbar spine bone mineral density and thoracic spine vertebral deformities in a prospective study of 79 post-menopausal population-based women aged 45-65 years has been investigated. Lumbar spine bone mineral density was measured using dual energy X-ray absorptiometry, and vertebral morphometry was assessed from lateral thoracic spine radiographs. Seven women (9%) were found to have one or more vertebral deformities in the thoracic spine (reduction in anterior or posterior height > 25%). Only one of these had a lumbar spine bone mineral density T score below -2.5, whilst the T score was between -1 and -2.5 in three and greater than -1 in three. Two of these women also had lumbar spine vertebral deformity but lumbar spine radiographs were normal in the remaining five. There were no significant differences in age, height, weight, hormone replacement therapy use or bone mineral density between women with and without thoracic spine fractures. These results demonstrate that vertebral deformities in the thoracic spine occur in a proportion of healthy post-menopausal women in the absence of densitometric or radiographic evidence of osteoporosis in the lumbar spine. Although often asymptomatic, the significance of these fractures lies in the increased risk of further fractures. In the future, morphometric X-ray absorptiometric techniques may prove valuable in the detection of these fractures and avoid the need for conventional radiography.

CT of a peripatetic intracranial foreign body

We report the CT appearances of a low-velocity missile that lodged within the brain and which subsequently migrated spontaneously back along the entry path. We review the literature of similar instances of migration and draw conclusions about the presurgical radiological management.

The use of ultrasound-guided cutting-needle biopsy in the neck

Histological analysis of an abnormal neck mass has traditionally required an excision biopsy under general anaesthetic. We evaluated the safety and accuracy of a new spring loaded cutting-needle for obtaining tissues cores of neck masses under ultrasound (US) guidance. Sixty biopsies were performed on an outpatient basis under local anaesthesia in 52 patients referred with a neck mass. Patients ranged in age from 10 months to 89 years and masses varied in size from 5 mm to 5 cm. Fifty-eight of the 60 biopsies provided a diagnostic histological specimen. Of the remaining two patients, one required open biopsy and the other returned for a second needle biopsy. All five cases of lymphoma were correctly diagnosed on needle biopsy; in three cases full tumour sub-classification was possible but in two patients an open biopsy was subsequently required. In 49 patients the needle biopsy obviated the need for a surgical biopsy for diagnostic purposes, although in 12 cases a therapeutic excision biopsy was performed. Apart from one subclinical haematoma, visualized on US, there were no immediate or delayed complications. In all patients, the histological diagnosis was compatible with subsequent clinical, radiological, surgical or autopsy findings. Cutting-needle biopsy of neck masses under US guidance is an effective and safe procedure which should be considered before resorting to routine surgery.

Sonography in the evaluation of the male anterior urethra

Contrast ascending urethrography is the technique most commonly used to evaluate the male anterior urethra. Sonography of the anterior urethra was prospectively evaluated in 24 consecutive referrals for conventional urethrography. In 11 patients both the sonographic and the contrast urethrograms were considered normal. Both studies demonstrated one or more strictures in nine patients but ultrasound also demonstrated periurethral cuffing in three of these. Sonography demonstrated a mucosal flap missed on the contrast study and also showed that suspected bubbles seen on the contrast study were true urethral filling defects. Diverticula were seen in three contrast studies. Two were demonstrated sonographically but the third, a shallow diverticulum in a patient with a complex stricture, was not seen on the sonogram. Mucosal irregularity was observed in five patients, and lack of urethral distensibility was demonstrated in a further five patients, by both techniques. Reflux into prostatic and Cowper's ducts could not be detected by ultrasound. Sonography offers advantages over conventional urethrography both in terms of abnormalities detected and convenience of the study.

Chest radiography guidelines for general practitioners: a practical approach

An intensive programme of guideline development and dissemination is not always practical. We designed general practitioner guidelines for chest radiography and disseminated them to a group of 33 practices selected randomly from the practices that refer more than five patients for chest radiography annually. The subsequent 2500 requests were analysed and demographic data, the referring practice and the relevant history noted. We documented a reduction in the proportion of referrals that were contrary to the guidelines by 30.5% (from 8.2% to 5.7%, P = 0.016), a reduction in referral rate with an inadequate history by 29.7% (from 15.5% to 10.9%, P = 0.0008) and an increase in the frequency that a presumptive diagnosis was stated by 14.5% (from 42.9% to 49.1%, P = 0.0025). There was no overall reduction in referral rate in the study group and the reasons for this are discussed. We conclude that guidelines for chest radiography are effective in reducing inappropriate requests and can also improve the clinical information provided.