Follow-up MR imaging of the alar and transverse ligaments after whiplash injury: a prospective controlled study.

BACKGROUND AND PURPOSE: The cause and clinical relevance of upper neck ligament high signal intensity on MR imaging in WAD are controversial. The purpose of this study was to explore changes in the signal intensity of the alar and transverse ligaments during the first year after a whiplash injury. MATERIALS AND METHODS: Dedicated high-resolution upper neck proton attenuation-weighted MR imaging was performed on 91 patients from an inception WAD1-2 cohort, both in the acute phase and 12 months after whiplash injury, and on 52 controls (noninjured patients with chronic neck pain). Two blinded radiologists independently graded alar and transverse ligament high signal intensity 0-3, compared initial and follow-up images to assess alterations in grading, and solved any disagreement in consensus. The Fisher exact test was used to compare proportions. RESULTS: Alar and transverse ligament grading was unchanged from the initial to the follow-up images. The only exceptions were 1 alar ligament changing from 0 to 1 and 1 ligament from 1 to 0. The prevalence of grades 2-3 high signal intensity in WAD was thus identical in the acute phase and after 12 months, and it did not differ from the prevalence in noninjured neck pain controls (alar ligaments 33.0% versus 46.2%, P = .151; transverse ligament 24.2% versus 23.1%, P = 1.000). CONCLUSIONS: Alar and transverse ligament high signal intensity in patients with WAD1-2 observed within the first year after injury cannot be explained by the trauma. Dedicated upper neck MR imaging cannot be recommended as a routine examination in these patients.

Cost-effectiveness analysis (CEA) of intravenous urography (IVU) and unenhanced multidetector computed tomography (MDCT) for initial investigation of suspected acute ureterolithiasis.

BACKGROUND: It is important to compare the cost and effectiveness of multidetector computed tomography (MDCT) and intravenous urography (IVU) to determine the most cost-effective alternative for the initial investigation of acute ureterolithiasis. PURPOSE: To analyze the task-specific variable costs combined with the diagnostic effect of MDCT and IVU for patients with acute flank pain, and to determine which is most cost effective. MATERIAL AND METHODS: 119 patients with acute flank pain suggestive of stone disease (ureterolithiasis) were examined by both MDCT and IVU. Variable costs related to medical equipment, consumption material, equipment control, and personnel were calculated. The diagnostic effect was assessed. RESULTS: The variable costs of MDCT versus IVU were EUR 32 and EUR 117, respectively. This significant difference was mainly due to savings in examination time, higher annual examination frequency, lower material costs, and no use of contrast media. As for diagnostic effect, MDCT proved considerably more accurate in the diagnosis of stone disease than IVU and markedly more accurate concerning differential diagnoses. CONCLUSION: MDCT had lower differential costs and a higher capacity to determine correctly stone disease and differential diagnoses, as compared to IVU, in patients with acute flank pain. Consequently, MDCT is a dominant alternative to IVU when evaluated exclusively from a cost-effective perspective.

The occurrence of asymptomatic and symptomatic simple hepatic cysts. A prospective, hospital-based study.

AIM: To examine the prevalence of asymptomatic and symptomatic liver cysts in a university hospital patient population using modern US equipment. METHODS: Abdominal US scans of 1541 cases referred during the period 21 January to 11 November 2000 were examined for hepatic cysts. RESULTS: Of 1541 cases, 174 (11.3%) were found to have hepatic cysts, i.e. 109 female (12.5%) and 65 (9.7%) male patients (9.7%). In 413 individuals younger than 40 years, no cysts were found. Above the age of 40 years, prevalence increased with age. CONCLUSION: By using modern US equipment, we found a higher prevalence of hepatic cysts than that reported in previous studies. Patient selection and the prevalence of liver cysts in the population from which the patients were referred may have influenced our results.

Biochemical and cytologic analysis of cystic contents in benign non-parasitic symptomatic hepatic cysts before and after ethanol sclerotherapy.

PURPOSE: To examine the fluid of liver cysts by cytologic and biochemical analysis before and after ethanol sclerotherapy in order to explore the etiology of cystic fluid reproduction after sclerotherapy. MATERIAL AND METHODS: The contents of 11 cysts in 11 patients were examined on the day of sclerotherapy, and 2-8 (mean 4.5) days later, and analysed for cytologic and biochemical parameters. RESULTS: Cytologic signs of acute or subacute inflammatory reaction were absent before and present in all cysts after sclerotherapy. Biochemical parameters reflecting the acute inflammatory reaction (CRP, orosomucoid and haptoglobine), changes in capillary permeability (protein, albumin), and the cystic epithelial function (bilirubin, alkaline phosphatase) were significantly elevated after sclerotherapy. CONCLUSION: The post-sclerotherapy fluid production is probably due to an inflammatory reaction. This may explain the success of performing sclerotherapy in one single session.

MR analysis of the transverse ligament in the late stage of whiplash injury.

PURPOSE: To analyse and classify structural changes in the transverse ligament in the late stage of whiplash injury by use of high-resolution MRI, and to evaluate the reliability of our classification. MATERIAL AND METHODS: Ninety-two whiplash-injured (2-9 years previously, mean 6 years) and 30 non-injured individuals underwent proton-weighted MR imaging of the craniovertebral junction in three orthogonal planes. Structural changes in the transverse ligaments were graded twice (grades 1-3) based on increased signal, independently by 3 radiologists with a 4-month interval. Inter- and intraobserver statistics were calculated by ordinary and weighted kappa (K). RESULTS: Image quality was excellent in 109 cases and slightly reduced in 13. Twenty-two out of 30 ligaments in the control group were classified as normal (73%) compared with only 32 out of 92 in the injured group (36%). Two or all 3 observers agreed in their grading in 101 out of 122 ligaments (83%). Intraobserver agreement (weighted K) was fair to good (0.33-0.73). Pair-wise interobserver agreement was fair (0.24-0.39). Reasons for divergent grading were insufficient knowledge of normal variations, low signal intensity in the peridental soft tissue obscuring the ligament and interpretation flaw. CONCLUSION: Whiplash trauma can damage the transverse ligament. By use of high-resolution proton-weighted MR images such lesions can be detected and classified. The reliability of this classification still needs improvement.

MRI of the tectorial and posterior atlanto-occipital membranes in the late stage of whiplash injury.

Our aim was to characterise and classify permanent structural changes in the tectorial and posterior atlanto-occipital membranes several years after a whiplash injury, and to evaluate the reliability of our classification. We obtained sagittal proton density-weighted images of the craniovertebral junction of 92 whiplash-injured and 30 uninjured individuals. Structural abnormalities in the two membranes were classified as grades 1-3 independently by three radiologists blinded for clinical information. Grading criteria were based on reduced tectorial membrane thickness, and elongation or rupture of the posterior atlanto-occipital membrane/dura mater complex. The same images were reassessed 4 months later. Image quality was graded good in 104 cases, slightly reduced in 13 and unsatisfactory in five. Of 117 tectorial membranes 31 (26.5%) showed grade 2 or 3 lesions, in the uninjured group none were grade 3 and only three were grade 2. Pair-wise interobserver agreement (weighted kappa) was moderate (0.47-0.50), while the intraobserver agreement was moderate to good (0.51-0.70). Of 117 posterior atlanto-occipital membranes 20 (17.1%) had grade 2 or 3 lesions; there was no grade 3 and only one grade 2 lesion in the uninjured group. Inter- and intraobserver agreement was good (0.61-0.74 and 0.65-0.86, respectively). Reduced image quality was the main reason for disagreement, but partial thinning and lateral tapering, as normal tectorial membrane variations, created difficulties in some cases. This study strongly indicates that whiplash trauma can damage the tectorial and posterior atlanto-occipital membranes; this can be shown on high-resolution MRI. Better knowledge of normal anatomical variations and improved image quality should increase the reliability of lesion classification.

MRI assessment of the alar ligaments in the late stage of whiplash injury--a study of structural abnormalities and observer agreement.

Our aim was to characterise and classify structural changes in the alar ligaments in the late stage of whiplash injuries by use of a new MRI protocol, and to evaluate the reliability and the validity of this classification. We studied 92 whiplash-injured and 30 uninjured individuals who underwent proton density-weighted MRI of the craniovertebral junction in three orthogonal planes. Changes in the alar ligaments (grades 0-3) based on the ratio between the high signal area and the total cross-sectional area were rated twice at a 4-month interval, independently by three radiologists. Inter- and intraobserver statistics were calculated by ordinary and weighted kappa. Cases classified differently were reviewed to identify potential causes for disagreement. The alar ligaments were satisfactorily demonstrated in all cases (244 ligaments in 122 individuals). The lesions, 2-9 years after the injury, varied from small high-signal spots to high signal throughout the cross-sectional area. Signal was highest near the condylar insertion in 82 of 94 ligaments, indicating a lesion near that insertion, and near the dental insertion in eight, indicating a medial lesion. No grade 2 or 3 lesion was found in the control group. At least two observers assigned the same grade to 214 ligaments (87.7%) on the second occasion. In 30 ligaments (12.3%) this agreement was not obtained. Pair-wise interobserver agreement (weighted kappa) was fair to moderate (0.31-0.54) in the first grading, improving to moderate (0.49-0.57) in the second. Intraobserver agreement (weighted kappa) was moderate to good (0.43-0.70). Whiplash trauma can cause permanent damage to the alar ligaments, which can be shown by high-resolution proton density-weighted MRI. Reliability of classification of alar ligament lesions needs to be improved.

Magnetic resonance imaging of the prostate.

Magnetic resonance imaging has been shown to be more accurate than other imaging modalities in the evaluation of both malignancies and various benign lesions of the prostate. Despite its superiority, because of its cost and low availability, magnetic resonance imaging should play a role as a problem-solver secondary to computed tomography or ultrasonography. The routine use of magnetic resonance imaging in the staging of prostate cancer before surgery cannot be justified on the basis of published data. Magnetic resonance imaging has been proved to be of value in the planning and delivery of different types of radiotherapy to patients with prostate cancer. Through the use of combined magnetic resonance imaging and the new modality, magnetic resonance spectroscopy, the accuracy and specificity of tumour detection and the delineation of tumour extent can be improved. Magnetic resonance technology is rapidly evolving, and in the near future, new possibilities such as biological imaging will have a great impact on magnetic resonance imaging of the prostate.

MRI assessment of normal ligamentous structures in the craniovertebral junction.

We have established an imaging protocol in order to characterise the normal ligamentous structures in the craniovertebral junction. Thirty volunteers without a history of car accident or head or neck trauma underwent MR imaging with 2-mm-thick proton-density-weighted sections in three orthogonal planes. The alar ligaments were clearly seen in every case and had three different configurations in cross-section: round, ovoid or wing-like. A broadening from lateral to medial in the coronal plane was observed in all cases. The transverse ligament was clearly demonstrated in 26 out of 30 cases. The ligament was flattened where it arched across the dens. Towards the insertions the ligament twisted into an oblique-horizontal orientation. The lower tectorial membrane had a median portion merging with the dura, and a lateral portion separated from it. Between the dens and clivus this membrane either merged totally with dura or was partly separated from it by a thin layer of fat. The posterior atlanto-occipital membrane was clearly demonstrated. It either merged with the dura or was partly or totally separated from it by a fat layer. The anterior atlanto-occipital membrane was inconsistently seen and could not be evaluated. Our refined MR protocol improves the visualisation of the craniovertebral ligamentous structures, and may in the future give new insight into post-traumatic neck disorders up to now poorly understood.

[Magnetic resonance tomography with endorectal coil for examination of prostate and seminal vesicles]. / Magnetisk resonanstomografi med endorektal spole for undersøkelse av prostata og saedblaerene.

MRI with an endorectal coil gives images of the prostate gland and seminal vesicles of higher quality than any other imaging modality. The use of an endorectal coil enables us to sample stronger radiofrequency signals from the prostate gland and seminal vesicles compared to a whole-body coil. This improves the contrast resolution in MR images and may give a higher spatial resolution by use of thin slices and a smaller slice gap. Intravenous MRI contrast is not used in our standard procedure. At Haukeland University Hospital, Norway, MRI with an endorectal coil is presently used as a tool for solving special problems in relation to detection and staging of prostate cancer, for example in patients with an abnormal s-PSA and negative sextant biopsies from the prostate gland. Furthermore, MRI with an endorectal coil may be used for the diagnosis of some benign diseases. The specific role of MRI with an endorectal coil in clinical use is not clarified; further research is needed. This article gives a short overview of technical aspects, imaging protocols, image reading, indications and diagnostic criteria for some diseases.

Use of pelvic surface coil MR imaging for assessment of clinically localized prostate cancer with histopathological correlation.

We evaluated the ability of magnetic resonance imaging (MRI) operating at 1.0 Tesla with a Helmholz pelvic surface coil to predict the pathological stage of prostate carcinoma. Radiological diagnosis was based on fast spin-echo axial T2-weighted images with and without frequency selective fat-suppression and fast spin-echo coronal T2-weighted images. Thirty-one consecutive patients (mean age 61 years, range 49 to 71 years) underwent pelvic MRI before radical prostatectomy. Correlation with whole-mount step-sections of the surgical specimens showed that the tumours were correctly localized in all but one prostate gland in which the tumour could not be seen on pelvic MRI. The transverse diameter of the visible tumour at pelvic MRI appeared to represent an approximate estimate of the true tumour dimension. Based on histopathologic whole-mount step-sections of the surgical specimens, 22 of 31 patients (71%) had tumours extending beyond the confines of the prostatic capsule. The specificity for MRI to predict capsular penetration and seminal vesicle invasion was relatively high (0.80 and 0.86, respectively). The sensitivity was acceptable for capsular penetration (0.62) but poor for seminal vesicle invasion (0.30).

MRI with an endorectal coil for staging of clinically localised prostate cancer prior to radical prostatectomy.

The purpose of this study was to evaluate the ability of MR imaging with an endorectal coil (erMRI) to predict the local pathological stage of prostatic carcinoma prior to radical prostatectomy. Thirty-one consecutive patients (median age 61 years, range 40-71 years) with clinically localised prostate cancer were assessed preoperatively by endorectal MRI (at 1.0 T). The pulse sequences consisted of fast spin-echo axial and coronal T2-weighted images and inversion recovery with two echoes for axial fat-suppressed images. The assessment of tumour stage and measurement of tumour dimension by erMRI were compared with the corresponding findings on whole-mount step sections of the surgical specimens. Postoperatively, 14 of the 31 patients (45 %) were found to have extracapsular extension, 7 with capsular penetration (CP) only, and 7 had a combination of CP and seminal vesicle invasion (SVI). Capsular penetration was detected by erMRI with a sensitivity of 0.71 and specificity of 0.47, whereas the sensitivity for SVI detection was 0.71 and the specificity 0.83. Endorectal MRI for staging clinically localised prostatic carcinoma gives a good prediction of invasion of the seminal vesicles but is unreliable in predicting capsular penetration.

Lymphangiography combined with biopsy and computer tomography to detect lymph node metastases in localized prostate cancer.

To evaluate the efficacy of lymphangiography combined with fine needle aspiration biopsy and computer tomography (CT) for lymph node staging in clinically localized prostate cancer. Prospective evaluation of nodal involvement was carried out using standard bipedal lymphangiography combined with fine needle aspiration biopsy (FNAB) in 70 patients (aged 47 to 75 years, mean age 63 years) with apparently locally confined prostate cancer before intended radical prostatectomy. Sixty-four patients also underwent computer tomography. Seventeen withdrew the decision to undergo a radical prostatectomy, leaving 53 patients with pathologic examination of the lymph nodes eligible for analysis. Lymph node metastases were diagnosed in 8 patients (8/53 = 15.1%). Three were diagnosed preoperatively by FNAB, 3 peroperatively by lymph node dissection and frozen section biopsy and an additional 2 at the final pathologic assessment. The sensitivity, specificity, positive and negative predictive values for lymphangiography and lymphangiography combined with FNAB in predicting nodal disease, based on the analysis of the 53 patients with known pathologic results, were 0.63, 0.76, 0.31, 0.92 and 0.38, 1.00, 1.00, 0.90, respectively. The corresponding values for CT staging were 0.25, 0.98, 0.67 and 0.87, respectively. The efficacy of bipedal lymphangiography alone or combined with FNAB or CT alone for assessment of nodal metastases is too low to be worthwhile for lymph node staging in localized prostate cancer patients with expected low or intermediate probability of nodal disease.

Tumour size measured by transrectal ultrasonography in the staging of prostate cancer before radical prostatectomy.

OBJECTIVE: To assess the diagnostic accuracy of transrectal ultrasonography (TRUS) in predicting the local extent of prostate cancer before radical prostatectomy. PATIENTS AND METHODS: From April 1990 to April 1993, 59 consecutive patients (mean age 63 years, range 49-71) with clinically localized prostate cancer were examined using TRUS before radical prostatectomy. Primary tumours were clinically categorized according to the TNM classification and biopsies graded histologically. Tumour size was measured as length on a longitudinal and height and width on a transverse ultrasonogram. The results from TRUS were compared with those from the histopathological examination of whole-mount step sections of the surgical specimens. RESULTS: In 50 patients, TRUS using standard criteria achieved sensitivity, specificity, positive- and negative predictive values (PPV, NPV) of 0.47, 0.63, 0.73 and 0.36, respectively, in predicting pathological stage. Dimensions were obtained from 45 patients with hypoechoic tumours; in a multivariate linear discriminant analysis the TRUS estimate of width was the best predictor of pathological stage. The sensitivity, specificity, PPV and NPV for tumour width from TRUS, using a threshold of 19 mm, were 0.42, 0.93, 0.93 and 0.43, respectively. CONCLUSION: Tumour width measured by TRUS may improve the assessment of the local extent of prostate cancer.

Transrectal ultrasonography to assess local extent of prostatic cancer before radical prostatectomy.

OBJECTIVE: To evaluate transrectal ultrasonography (TRUS) with a 7 mHz rotating probe as a staging procedure in 33 patients with localized prostatic carcinoma. PATIENTS AND METHODS: The ultrasound scans were compared to histopathological whole-mount step sections of the surgical specimens. Twenty-five of the patients had tumours with pathological stage T3 (pT3) and eight had tumours with stage pT2 giving a prevalence of extracapsular growth of 0.76. RESULTS: The overall sensitivity, specificity, positive and negative predictive values for detection of extracapsular tumour growth by TRUS of prostatic cancer were found to be 0.68, 0.63, 0.85 and 0.38, respectively. Six tumours showed solely microscopic foci of extracapsular tumour growth. CONCLUSION: This technique gives a high percentage of both understaging (32%) and overstaging (37%) and therefore TRUS is an unreliable tool in the staging protocol prior to radical prostatectomy.

Inability of refined CT to assess local extent of prostatic cancer.

A refined procedure for CT was evaluated as a staging procedure in 19 patients with localized prostatic carcinoma. The CT images were compared to histopathologic whole-mount step sections of the surgical specimens. Fourteen of the patients had pathologic stage T3 (pT3) and 5 had stage pT2 giving a prevalence of extracapsular growth of 0.74. The CT images were read by 2 radiologists independently with a diagnostic accuracy of 0.37 for both observers. This is no better than in previous studies using a routine CT procedure. We conclude that CT is of little value in the staging protocol for the local extent of prostatic carcinoma before radical prostatectomy.

Transrectal ultrasonography in the staging of localized prostatic carcinoma. A pilot study.

Transrectal ultrasonography (TRUS) was evaluated as a staging procedure in ten patients with localized prostatic carcinoma. The ultrasound images were correlated to histopathological whole-mount step sections of the surgical specimens after radical prostatectomy. Nine of the patients had pathological stage T3 (pT3) and only one was pT2. TRUS gave a diagnostic accuracy of 60% compared to 10% both for digital rectal examination (DRE) and computer tomography (CT) in detecting extracapsular tumor spread. We conclude so far that TRUS is superior to DRE and CT in detecting extracapsular tumor spread. Further we state that whole-mount step section of the surgical specimens is mandatory in order to achieve a correct pathological staging (pT-stage).

Prostatic abscess: imaging with transrectal ultrasound. Case report.

A 50-year-old man presented with acute urinary retention and urosepsis. Transrectal ultrasonography (TUS) of the prostate demonstrated an abscess. Transperineal US-guided aspiration of pus, urinary bladder catheterization together with systemically administered antibiotics led to an uneventful recovery. TUS was a rapid diagnostic aid for differentiation between prostatitis and prostatic abscess; the appearance of an hypoechoic process within the prostate suggests an abscess.