Association of femoral intercondylar notch morphology, width index and the risk of anterior cruciate ligament injury

PURPOSE

To determine the relationship between femoral notch morphology, femoral notch width index and anterior cruciate ligament tears using magnetic resonance imaging of the knee.

METHODS

This retrospective study was conducted on 560 patients who had magnetic resonance imaging (MRI) examinations of the knee between February 2010 and June 2011. Two morphological changes were investigated: the shape of the femoral notch and its width index. The femoral notch shape was classified into one of three types: Type A, which is a narrow (Stenotic) notch that appears narrowed from the base to the midsection as well as at the apex; Type U, in which the midsection does not taper, allowing for a wider contour to the notch than Type A; and Type W, which has the characteristics of Type U but with two apparent apices. The femoral notch width index was calculated as a ratio of central notch width and transcondylar or intercondylar width; values of 0.270 or more were considered as normal and values of 0.269 or less were considered as below normal. These measurements were correlated with the presence or absence of anterior cruciate ligament (ACL) tears.

RESULTS

Of 560 patients, there were 280 cases of ACL tear. Of the 560 patients, 240 had a Type A femoral notch shape and 320 had a Type U or W femoral notch shape. Of those with Type A, 73 % (176 patients) had ACL tears, and of those with Type U or W, 32 % (104 patients) had ACL tears. Statistical analysis showed that the Type A notch correlated with ACL injury (p value < 0.0001). The femoral notch width index was low in 37 % (88 subjects) with Type A notch compared with 27.5 % (88 subjects) with Type U or W notches. Of the 280 subjects with ACL tear, only 17 % (48 patients) had a reduced femoral notch index.

CONCLUSION

This study showed that the Type A femoral notch appears to be a risk factor for ACL injury, whereas a reduced notch index has no significant correlation to ACL injury.

LEVEL OF EVIDENCE

III.

Significance of Virchow-Robin spaces in patients newly diagnosed with multiple sclerosis: a case-control study in an Arab population

OBJECTIVE

To assess the frequency and extent of dilatation of Virchow-Robin (VR) spaces at three levels of the brain in patients of Arab ethnicity in Kuwait recently diagnosed with multiple sclerosis (MS) and compare the results with age- and gender-matched controls.

METHODS

The magnetic resonance imaging (MRI) scans performed within 3 months of the clinical diagnosis of 80 patients recently diagnosed with active MS were compared to those of 80 age- and gender-matched controls with headache but without any neurological deficits for the frequency and size of VR spaces. MRI was done with noncontrast axial and coronal T(1)W FSE, axial T(2)W FSE, axial T(2)W FLAIR and sagittal FLAIR sequences followed by postcontrast axial and coronal T(1)W sequences. The frequency of VR spaces in MS patients and controls at midbrain, lenticulostriate vessels and supraventricular levels was analyzed using a two-tailed McNemar test.

RESULTS

There was no difference in the frequency of VR spaces at the levels of the midbrain, lenticulostriate vessels and supraventricular white matter between MS patients and controls. In the supraventricular region, however, there were 91 dilated VR spaces in 26 (32%) of the MS patients while in the control group, there were 8 dilated VR spaces in 6 (7.5%) patients and the difference was statistically significant (p < 0.0001).

CONCLUSION

The data showed that dilated VR spaces in the supraventricular region could potentially be used as a marker for MS and as a prognostic tool. However, further studies with a larger population are needed to further evaluate and confirm this observation.

Fat-saturated post gadolinium T1 imaging of the brain in multiple sclerosis

BACKGROUND

Magnetic resonance imaging (MRI) is of vital importance in the diagnosis and follow-up of patients with multiple sclerosis (MS). Imaging sequences better demonstrating enhancing lesions can help in detecting active MS plaques.

PURPOSE

To evaluate the role of fat-saturated gadolinium-enhanced T1-weighted (T1W) images of the brain in MS and to assess the benefit of performing this additional sequence in the detection of enhancing lesions.

MATERIAL AND METHODS

In a prospective study over a six-month period, 70 consecutive patients with clinically diagnosed MS were enrolled. These constituted 14 male and 56 female patients between the ages of 21 and 44 years. All the patients underwent brain MRIs on a 1.5 Tesla Magnet. Gadolinium-enhanced T1 images with and without fat saturation were compared and results were recorded and analyzed using a conspicuity score and McNemar test.

RESULTS

There were a total of 157 lesions detected in 70 patients on post-contrast T1W fat-saturated images compared with 139 lesions seen on the post-contrast T1W fast spin-echo (FSE) images. This was because 18 of the lesions (11.5%) were only seen on the fat-saturated images. In addition, 15 lesions were more conspicuous on the fat saturation sequence (9.5%). The total conspicuity score obtained, including all the lesions, was 2.24 +/-0.60 (SD). Using the two-tailed McNemar test for quantitative analysis, the P value obtained was <0.0001.

CONCLUSION

T1W fat-saturated gadolinium-enhanced images show better lesion enhancement than T1W images without fat saturation.

Value of kidney-ureter-bladder radiography in the erect position in addition to standard intravenous urography examination

OBJECTIVES

To determine if additional kidney-ureter-bladder radiography in the erect position can improve the diagnostic yield of standard intravenous urography (IVU) examination.

SUBJECTS AND METHODS

This prospective study was conducted from March to July 2007 on 108 consecutive patients (65 males and 43 females, age ranging from 20 to 50 years) who were referred to the Department of Radiology, Al-Amiri Hospital, Kuwait, for IVU examinations. After 15 min, a film was done in the erect position in addition to the routine IVU protocol.

RESULTS

Additional information was demonstrated in the erect radiograph as follows: detecting nephroptosis in 18 (17%) patients, improved visualization of the ureters in 58 (54%) patients, and differentiation between phleboliths and ureteric stone was possible in 12 (11%) patients.

CONCLUSIONS

Our study demonstrated significant additional findings in the erect position (at 15 min) compared to the supine position.

Accuracy of the Fischer scoring system and the Breast Imaging Reporting and Data System in identification of malignant breast lesions

BACKGROUND AND OBJECTIVES

Fischer developed a scoring system in 1999 that made identifying malignnant lesions much easier for inexperienced radiologists. Our study was performed to assess whether this scoring system would help beginners to accurately diagnose breast lesions on magnetic resonance (MR) imaging and to assess the correlation between the magnetic resonance mammography Breast Imaging Reporting and Data System (MRM BI-RADS) grade and the final diagnosis.

PATIENTS AND METHODS

The lesion morphology and contrast kinetics of 63 masses in 41 patients were evaluated on MRI and accorded a MRM BI-RADS final assessment category using the Fischer scoring system. The accuracy was evaluated after the final diagnosis was obtained by tissue sampling and follow-up imaging.

RESULTS

There were 25 malignant and 30 benign lesions. Eight lesions were seen by MRI only and we could not verify their pathology since we did not have MR-guided biopsy facilities at the time of the study. On MR mammography, the proven carcinomatous lesions were characterized as BI-RADS category V in 16 (64%), category IV in 7 (28%), and category III in 2 (8%) lesions. Benign lesions were graded as category V in 3 (10%), category IV in 6 (20%), and category III in 3 (10%), category II in 10 (33%) and category I in 8 (27%) lesions. The MRM BI-RADS category accurately predicted malignancy in 92% and a benign pathology in 70% of the lesions. The overlap between the MRM features of chronic inflammatory lesions and carcinomas resulted in a lower accuracy in diagnosing benign as compared to malignant lesions.

CONCLUSION

The MRM BI-RADS lexicon using the Fischer scoring system is useful and has a high predictive value, especially for malignant breast lesions, and is easy to apply. Overlapping features between benign inflammatory and malignant lesions might yield a reduced accuracy in inflammatory pathologies.

Breast magnetic resonance imaging: initial experience in Kuwait

OBJECTIVE

To report our initial experience of breast magnetic resonance imaging (MRI) in Kuwait in order to identify and characterize breast lesions.

SUBJECTS AND METHODS

In 58 patients ranging in age from 25 to 64 years, breast MRI was performed as a problem-solving tool (29); for suspicious local relapse of the treated breast (6); to search for a primary breast cancer in patients with metastatic axillary lymph nodes (5); for local staging of breast cancer (5); breast implants (6); screening in high-risk patients (3), and differentiation between inflammation and inflammatory carcinoma (4). Sagittal fat-saturated T(2) and axial T(1) images were obtained before, and axial fat-saturated T(1) and dynamic sagittal fat-saturated T(1)-weighted images after contrast enhancement in a 1.5-tesla closed magnet. The diagnostic criteria were based on the morphology and kinetics of the lesion. Findings were validated by tissue sampling or radiological follow-up.

RESULTS

Seventy breast lesions (25 malignant, 38 benign and 7 lesions detected by MRI only) were identified in the 58 patients. The sensitivity, specificity, and positive and negative predictive values of MRI in diagnosing malignant breast lesions were 96, 67, 71 and 95%, respectively, while the accuracy was 80%.

CONCLUSION

This initial experience is comparable to other published data. Future plans for improving image spatial resolution and MR-guided procedures have been taken into consideration.

Intraoperative ultrasound in determining the extent of resection of parenchymal brain tumours--a comparative study with computed tomography and histopathology

BACKGROUND

Radical excision of parenchymal brain tumours is generally associated with a better long-term outcome; however, it is difficult to ascertain the extent of resection at surgery. We used intra-operative ultrasound [IOUS] to help detect residual tumour and define the tumour-brain interface.

METHODS

Thirty-five patients with parenchymal brain lesions including 11 low-grade and 22 high-grade tumours and 2 inflammatory granulomata were included in the study. The IOUS was used to localize tumours not seen on the surface, define their margins and assess the extent of resection at the end of surgery. Multiple samples from the tumour-brain interface which were reported as tumour or normal tissue on IOUS were submitted to histopathology. The IOUS findings were compared with a postoperative contrast enhanced computed tomogram [CT] and with histopathology.

RESULTS

All tumours irrespective of histology were hyperechoic on IOUS. IOUS was useful in localizing those tumours not seen on the surface of the brain. In 71.4% of cases IOUS was useful in defining their margins, however in the remaining cases the margins were ill-defined. The tumour margins were ill-defined in those treated previously by radiation. With regard to the extent of excision, after excluding the cases who were irradiated, it was found that in the 28 patients who had parenchymal neoplasms, there was concordance between the ultrasound findings and the postoperative CT scan in 23 cases. Of the 79 samples taken from the tumor-brain interface which were reported as tumour on ultrasound, 66 had histopathological evidence of tumour while 13 samples were negative for tumour. On the other hand, in the tissue sent from 17 sites where the IOUS showed no residual tumour, 2 were positive for tumour on histopathology while 15 were negative.

INTERPRETATION

In conclusion, IOUS is a cheap and useful real-time tool for localizing tumours not seen on the brain surface, for defining their margins and for determining the extent of resection.

Pneumothorax preceding pulmonary blastoma in a child

Serial plain radiographic, ultrasound and CT findings of an unusual case of pulmonary blastoma are described with a review of the literature.