Israel Medical Association Journal

Background: Metal-on-metal total hip prostheses (MoM-THR) have been shown to produce hypersensitivity reactions and fluid collection (pseudotumor) by the hip as well as high blood metal ions levels (BMILs).

Objectives: To evaluate the magnetic resonance imaging (MRI) signal-to-noise ratio (S/N) in selected body tissues around the hip of patients who underwent MoM hip replacement and to correlate to BMILs.

Methods: Sixty-one MRI hip examinations in 54 post-MoM-THR patients (18 males, 36 females, mean age 65 years) were retrospectively evaluated independently by two readers. The mean S/N ratio in a region of interest was calculated for periprosthetic pseudotumor collection (PPC), the bladder, fat, and muscle on axial T1w, FSE-T2w, and short tau inversion recovery (STIR) sequences on the same location. BMILs were retrieved from patient files.

Results: PPC was detected in 32 patients (52%) with an average volume of 82.48 mm³. BMIL did not correlate with the presence of PPCs but positively correlated with the PPC's volume. A trend for positive correlation was found between BMILs and S/N levels of STIR images for muscle and bladder as well as for PPC and cobalt levels. A trend for correlation was also seen between BMIL with PPC's T1 w S/N.

Conclusions: Alteration of MRI S/N for different hip tissues showed a tendency for correlation with BMILs, possibly suggesting that metal deposition occurs in the PPC as well as in the surrounding tissues and bladder.

Background: Magnetic resonance imaging (MRI), which has recently become the leading imaging modality in the study of ankylosing spondylitis (AS), has not been evaluated in the assessment of disease-specific changes at the craniocervical junction (CCJ) in patients with AS.

Objectives: To describe the spectrum of active inflammatory lesions at the CCJ using MRI in a cohort of patients with AS and neck pain.

Methods: The study included 18 patients with AS presenting with neck pain and a control group of 9 fibromyalgia patients matched for age and levels of neck pain. All patients underwent a focused rheumatologic examination, X-ray of the cervical spine, and a 3T MRI study, which included STIR, CUBE T2, FSE and FSE FAT SAT sequences before and after administration of gadolinium.

Results: The median age of AS patients was 43 years with a median disease duration of 7 years. Fifteen of 18 patients were under biologic treatment. Seven of 18 AS patients had evidence of cervical syndesmophytes on X-ray films. Active inflammatory lesions of atlanto-occipital joints and apical and alar ligaments were detected in MRIs in 2 out of the 18 patients with AS and in none of the patients with fibromyalgia. Both AS patients with active inflammation of CCJ detected on MRI received treatment with biological agents prior to and during the study.

Conclusions: Active inflammation of both entheses and joints of the CCJ can be demonstrated by MRI in patients with AS.

Axial spondyloarthritis (axSpA) covers the stage of non-radiographic axial spondyloarthritis (nr-axSpA) and classic ankylosing spondylitis. The pathognomonic findings of axSpA are mainly inflammatory and osteoproliferative changes in the sacroiliac joints (SIJ) and the spine. Various imaging techniques are being used in daily practice for assessment of disease-specific changes, such as periarticular bone marrow edema, erosions, sclerosis, fat metaplasia and ankylosis in the SIJ or spondylitis, spondylodiscitis, facet joint involvement, or syndesmophytes in the spine of patients with axSpA. Conventional radiographs are still considered the gold standard for assessment of structural changes, while the method of for detection of inflammatory changes is magnetic resonance imaging (MRI).

A result for an MRI in the SIJ is considered positive for axSpA when more than one lesion is present on one MRI slice, If there is one lesion only, this should be present on at least two consecutive slices. For the spine, inflammatory lesions should preferably be located in the corner of the vertebral bodies, while occurrence of spondylitis in three or more vertebral corners is considered highly suggestive of axSpA.

This review gives a detailed overview about the benefits and limitations of all available imaging techniques in patients with axSpA, explains the usage of imaging techniques in the context of diagnosis and differential diagnosis of the disease, and reports on the potential future trends in the area of imaging of the axial skeleton in patients who are suspicious for this diagnosis.

Background: Silicone breast augmentation is a common cosmetic surgery. Previous case reports demonstrated lymphadenopathy in the presence of implant ruptures.

Objectives: To investigate the association between enlarged axillary lymph nodes and silicone implant ruptures as seen on breast magnetic resonance imaging (MRI).

Methods: Two groups were derived retrospectively from breast MRI reports in our institution for the period December 2011–May 2014. A search of our hospital records for "silicone" and "lymph node" was performed (group A), and the relationship between the presence of enlarged nodes and ruptures was evaluated. The prevalence of ruptures in the presence of nodes was calculated and the association between MRI imaging features and ruptures evaluated. A search for "silicone" and "implant rupture" was performed (group B) and, as for group A, the relationship between the presence of ruptures and nodes was evaluated and the prevalence of enlarged nodes in the presence of ruptures calculated.

Results: Group A comprised 45 women with enlarged nodes. Intracapsular ruptures were associated with nodes (P = 0.005), while extracapsular ruptures showed a trend of association with nodes (P = 0.08). The prevalence of ruptures in the presence of nodes was 31.4%. Nodes associated with ruptures showed a strong silicone signal (P = 0.008) and absent enhancement (P = 0.005). Group B comprised 73 women with ruptures. Enlarged nodes were associated with both intra- and extracapsular ruptures (P < 0.001 and P = 0.002 respectively). The prevalence of nodes in the presence of ruptures was 22.2%.

Conclusions: Enlarged axillary nodes were associated with ruptures in two groups of patients. This finding can guide clinical decisions when either enlarged nodes or ruptures are encountered in patients with silicone implants. The association between silicone lymphadenopathy and implant rupture raises concerns regarding the role of rupture in silicone-induced systemic disease.

 

Background: Automated breast volumetric sonography (ABVS) is a new technology with various possible applications.

Objectives: To compare ABVS and breast magnetic resonance imaging (MRI) in the surveillance of women with BRCA1/2 gene mutation carriers.

Methods: We conducted a prospective study in Jewish female BRCA1/2 mutation carriers who underwent breast MRI and ABVS. The results of both exams performed 6 months apart or less, and relevant clinical data, were reviewed. The BIRADS results were divided into three subgroups according to subsequent expected management: BIRADS 1-2 (normal study), BIRADS 3 (probably benign finding), and BIRADS 4 and 5 (suspicious findings). BIRADS 0 and 6 scores were excluded from the study. Distribution of ABVS and MRI BIRADS scores were compared using McNemar's test, and concordance was calculated using the Cohen kappa test.

Results: Overall, 68 women, 40 BRCA1 and 28 BRCA2 mutation carriers, age range 26–69 (mean 44.55 ± 12.1 years), underwent 79 paired ABVS and MRI examinations. McNemar's test calculations showed no significant difference between MRI and ABVS BIRADS score distribution. Cohen’s kappa test resulted in k = 0.158, an agreement that can be described as only "slight agreement" between both modalities. Of 14 discordant cases there was one cancer, revealed by MRI and not by ABVS performed 6 months prior to MRI.

Conclusions: ABVS showed slight agreement with MRI in BRCA1/2 mutation carriers. These preliminary results on a small group of healthy high risk patients suggest that the diagnostic abilities of ABVS are inferior to MRI. Further studies encompassing larger groups are needed.

 

The term non-radiographic axial spondyloarthritis (nrAxSpA) was coined for patients who have a clinical picture of ankylosing spondylitis (AS) but do not exhibit radiographic sacroiliitis. The ASAS classification criteria for nrAxSpA, ensuring the recruitment of homogenous study cohorts, were accepted in 2009, although the respective diagnostic criteria for daily clinical practice have not yet been developed. The clinical diagnosis should be based on the composite of clinical symptoms and signs of the disease, HLA B27 status, and magnetic resonance imaging (MRI) of sacroiliac joints. Notably, a negative MRI or HLA B27 does not exclude the diagnosis in patients with a high clinical suspicion for nrAxSpA. The prevalence of nrAxSpA is similar to that of AS, but the former has a higher female preponderance. The rate of progression of nrAxSpA to the radiographic stage of disease (AS) ranges from 10% to 20% over 2 years. Current treatment strategies for nrAxSpA are the same as for AS and include non-steroidal anti-inflammatory drugs and inhibitors of tumor necrosis factor-alpha. While this review summarizes the current achievements in the field of nrAxSpA, further understanding of the epidemiology and natural history of the disease and, particularly, mechanisms of inflammation and subsequent new bone formation is essential for the development of new treatment strategies for nrAxSpA patients. 

Background: The practice of administering intravenous contrast to children varies by institution depending on their routine. 

Objectives: To assess the necessity of routine contrast administration in brain magnetic resonance imaging (MRI) of pediatric outpatients referred for chronic headache workups. 

Methods: We conducted a retrospective review of consecutive pediatric brain MRI examinations performed during January and February 2014 in 30 pediatric outpatients referred for evaluation of chronic headache. Independent review was performed by two board-certified neuroradiologists. The raters reviewed each MRI first as a non-contrast examination (without seeing the post-contrast images) and then with post-contrast images. 

Results: No abnormalities were found in six patients. One patient had an indeterminate finding of a tubular cerebellar lesion requiring follow-up. In the remaining patients (n=23), the findings were subclinical and included: mucosal thickening in the paranasal sinuses in 9 patients, cystic changes of the pineal gland in 8 (size 2–9 mm), small developmental venous anomalies in 6, non-specific FLAIR hyperintensities in 4, opacification of the mastoids in 2, and telangiectasia in 1 patient. The subclinical cases that were missed on pre-contrast images were: one small developmental venous anomaly, one telangiectasia and one small pineal cyst, none of which hold clinical significance. All kappa inter-rater and intra-rater agreement scores resulted in values above 0.75, excellent agreement according to Fleiss guidelines.

Conclusions: There seems to be little reason to medically justify large-scale use of routine IV contrast administration to evaluate a brain MRI of pediatric patients referred for chronic headache. 

 

Breast magnetic resonance imaging (MRI) has an important role in the detection and diagnosis of breast cancer. Suspicious findings on MRI are further evaluated with ultrasound. This case series illustrates the use of automated breast volumetric ultrasound (ABVS) as a tool for second-look ultrasound (SLUS) following MRI. Seven women underwent breast MRI with findings necessitating SLUS. ABVS was used for second look and all MRI lesions were detected. Four cancers, one fibroadenoma and two benign lesions, were diagnosed. This case series shows that ABVS can be used as a tool for SLUS following MRI and in some cases is superior to hand-held ultrasound.

Background: Medical evaluation of a suspected meniscus injury begins with a history-taking and physical examination. Suspected meniscus injuries not responding to treatment are usually sent for imaging to confirm the diagnosis before arthroscopy. Tc-MDP bone single photon emission computed tomography (SPECT) scan has been suggested as an alternative to magnetic resonance imaging (MRI) in evaluating suspected knee meniscus tears.

Objectives: To examine the accuracy of knee SPECT as a tool to identify meniscus tears versus that of MRI as compared to the gold standard of arthroscopy.

Methods: The Israel Defense Forces database for 2005 through 2009 was searched according to the key words knee MRI, knee SPECT and knee arthroscopy. We identified 330 subjects who had undergone both a single knee SPECT and a single knee MRI prior to knee surgery. The medical files of 193 of the 330 subjects were randomly selected for review. A comparison was made between the preoperative SPECT and MRI studies and the arthroscopic finding. The sensitivity, specificity and accuracy were calculated.

Results: The subjects’ age was 21.3 ± 3.9. The agreement between SPECT and arthroscopy was 0.14 for the medial meniscus and 0.29 for the lateral meniscus. The agreement between MRI and arthroscopy was 0.59 for the medial meniscus and 0.69 for the lateral meniscus. SPECT scan was found to be 61% sensitive, 54% specific and 58% accurate in detecting common knee pathology, whereas MRI was found to be 95% sensitive, 67% specific and 85% accurate.

Conclusions: Knee SPECT has a lower sensitivity, specificity and accuracy than MRI in evaluating meniscal injuries and its use can result in increased unnecessary surgery.

Objectives: To measure the tumor-to-breast volume ratio using MRI in order to assess whether there is a correlation between this ratio and the type of surgery selected (breast-conserving or mastectomy).

Methods: The volumes of the tumor and the breast and the tumor-to-breast volume ratio were retrospectively calculated using preoperative breast MRI in 76 patients who underwent breast-conserving surgery or mastectomy.

Results: Breast-conserving surgery (lumpectomy) was performed in 64 patients and mastectomy in 12. The average tumor-to-breast volume ratio was 0.06 (6%) in the lumpectomy group and 0.30 (30%) in the mastectomy group (P < 0.0001).

Conclusion: The tumor-to-breast volume ratio correlated with the type of surgery. As measured on MRI, this ratio is an accurate means of determining the type of surgery best suited for a given patient. It is recommended that MRI-determined tumor-to-breast volume ratio become part of the surgical planning protocol for patients diagnosed with breast cancer.