Israel Medical Association Journal

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.

Ovarian cancer is a major cause of cancer death among women worldwide, and particularly in Israel. Although the disease at stage IA has 5 year survival rates of over 90%, early detection methods are not sufficiently accurate. Consequently, ovarian cancer is typically diagnosed late, which results in high fatality rates. An excellent candidate for early ovarian cancer detection would be in vivo magnetic resonance spectroscopy (MRS) because it is non-invasive and free of ionizing radiation. In addition, it potentially identifies metabolic features of cancer. Detecting these metabolic features depends on adequate processing of encoded MRS time signals for reconstructing interpretable information. The conventional Fourier-based method currently used in all clinical scanners is inadequate for this task. Thus, cancerous and benign ovarian lesions are not well distinguished. Advanced signal processing, such as the fast Padé transform (FPT) with high-resolution and clinically reliable quantification, is needed. The effectiveness of the FPT was demonstrated in proof-of-concept studies on noise-controlled MRS data associated with benign and cancerous ovaries. The FPT has now been successfully applied to MRS time signals encoded in vivo from a borderline serous cystic ovarian tumor. Noise was effectively separated out to identify and quantify genuine spectral constituents that are densely packed and often overlapping. Among these spectral constituents are recognized and possible cancer biomarkers including phosphocholine, choline, isoleucine, valine, lactate, threonine, alanine, and myoinositol. Most of these resonances remain undetected with Fourier-based in vivo MRS of the ovary. With Padé optimization, in vivo MRS could become a key method for assessing ovarian lesions, more effectively detecting ovarian cancer early, thereby improving survival for women afflicted with this malignancy.

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: Pregnant women with acute abdominal pain pose a diagnostic challenge. Delay in diagnosis may result in significant risk to the fetus. The preferred diagnostic modality is magnetic resonance imaging (MRI), since ultrasonography is often inconclusive, and computed tomography (CT) would expose the fetus to ionizing radiation

Objectives: To describe the process in setting up an around-the-clock MRI service for diagnosing appendicitis in pregnant women and to evaluate the contribution of abdominal MR in the diagnosis of acute appendicitis.

Methods: We conducted a retrospective study of consecutive pregnant women presenting with acute abdominal pain over a 6 year period who underwent MRI studies. A workflow that involved a multidisciplinary team was developed. A modified MRI protocol adapted to pregnancy was formulated. Data regarding patients' characteristics, imaging reports and outcome were collected retrospectively. 

Results: 49 pregnant women with suspected appendicitis were enrolled. Physical examination was followed by ultrasound: when positive, the patients were referred for MR scan or surgery treatment; when the ultrasound was inconclusive, MR scan was performed. In 88% of women appendicitis was ruled out and surgery was prevented. MRI diagnosed all cases with acute appendicitis and one case was inconclusive. The overall statistical performance of the study shows a negative predictive value of 100% (95%CI 91.9–100%) and positive predictive value of 83.3% (95%CI 35.9–99.6%).

Conclusions: Creation of an around-the-clock imaging service using abdominal MRI with the establishment of a workflow chart using a dedicated MR protocol is feasible. It provides a safe way to rule out appendicitis and to avoid futile surgery in pregnant women.

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.

 

Background: Neurolathyrism is a toxic nutritional disorder caused by consumption of the grass pea, Lathyrus sativus. The disease, which manifests as an acute or insidiously evolving spastic paraparesis, continues to occur throughout Africa and Asia. Research on this disease is limited, and to our knowledge no imaging studies of patients with neurolathyrism have been published. 

Objectives: To better localize the site of damage in neurolathyrism using advanced imaging methods. 

Methods: Three male patients, immigrants from Ethiopia, were included in the study. All had a history of arrested spastic paraparesis that had evolved before their emigration from Ethiopia, and a past history of exposure to grass pea without any other cause. Functional magnetic resonance imaging (fMRI) included simple motor tasks to evaluate cortical motor areas. Anatomic scans included diffusion tensor imaging (DTI) to evaluate the corticospinal tracts.

Results: In all patients clear activation was found in motor regions and the patients’ activity pattern was qualitatively similar to that in control subjects. In one patient in whom clinical symptoms were asymmetric, an asymmetric activity pattern in M1 was identified. DTI analysis identified intact corticospinal tracts connecting the pons and the primary motor regions, similar to control subjects. 

Conclusions: Advanced neuroimaging clearly identified well-functioning motor regions and tracts in neurolathyrism patients, suggesting a spinal etiology.

 

Background: Although fat grafting is a common technique to repair defects after breast cancer reconstruction surgery and has a low complication rate, the relation between fat grafting and the risk of breast cancer is unknown. Clinical trials to investigate this connection can elucidate the benefits and potential risks of fat grafting in oncology patients.

Objectives:To establish an efficient experimental model, using magnetic resonance imaging (MRI) scans, for comparing different breast tumor study groups post-fat grafting. 

Methods: Breast tumor cells were injected into immunocompromised mice. After tumors formed they were removed. Liposuction was performed in a female human donor and fat was collected. Cells were extracted from the fat by enzymatic digestion. Immunocompromised mice were randomized into four groups: a preliminary experiment group and three equal groups according to the type of fat graft: (i) fresh fat enriched with adipose-derived mesenchymal stem cells (AdMSCs), (ii) fresh fat without cell enrichment, and (iii) no fat injected. Tumor volume was assessed by serial MRI scans. 

Results: The rate of tumor growth was higher in the enriched fat group compared to the non-enriched fat group. 

Conclusions: This experimental model is an effective measurable method, allowing future investigation of the effect of autologous fat on breast cancer.

 

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.