Echo-planar DWI variants: A comparative study in vertebral marrow pathology.

PURPOSE: Single-shot echo-planar imaging (ss-EPI) has limited application in vertebral column imaging due to numerous artifacts. Therefore, we aimed to compare readout-segmented echo-planar imaging (rs-EPI) to ss-EPI and assess its value in the differential diagnosis of vertebral infectious, tumoral infiltrative, and degenerative disorders. MATERIALS AND METHODS: Sixty-six adult patients with spondylodiscitis (SD, n = 26), tumoral infiltration (TI, n = 20), or Modic type I degeneration (DE, n = 20) findings on spinal magnetic resonance imaging (MRI) included in this retrospective study. Two radiologists scored images for quality on a 4-point scale (image resolution, degree of geometric distortion, lesion selectivity, and diagnostic reliability) and measured signal intensity (SI), apparent diffusion coefficient (ADC), signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). DE and SD groups also united to form the benign group. RESULTS: In all groups, rs-EPI performed better than ss-EPI in image quality, SNR, and CNR (p < .05). The difference between mean pathological ADC (ADCP) in the two sequences was statistically significant (p < .05). There was no significant difference between the groups in terms of ADCP in rs-EPI (p = .229), unlike ss-EPI (p = .025). Pathological SI (SIP) and CNR in rs-EPI were significantly higher in the malignant group than benign group (p = .002, p < .001). In rs-EPI, no significant difference was found between malignant and benign groups' ADCP (p = .13). CONCLUSION: The rs-EPI is a diffusion-weighted imaging (DWI) method with higher image quality that diminishes motion-induced phase errors and increases resolution through phase corrections. However, the distinction of malignant and benign vertebral bone marrow pathologies is unsatisfactory for rs-EPI compared with ss-EPI.

The Prevalence of Lumbar Paraspinal Muscle Fatty Degeneration in Patients with Modic Type I and I/II End Plate Changes.

STUDY DESIGN: Retrospective case control. PURPOSE: The authors of this study assessed whether the prevalence of paraspinal fatty degeneration correlates with the presence of Modic type I and I/II change in patients with low back pain (LBP). OVERVIEW OF LITERATURE: Modic changes are bone marrow and end plate changes visible on magnetic resonance imaging. METHODS: A consecutive series of 141 patients who attended the neurosurgery outpatient clinic between April 2017 and September 2017 for nonspecific LBP were evaluated. Sixty-one patients with single-level Modic type I or I/II change constituted the patient group. Eighty age-, gender-, and body mass index (BMI)-matched patients without any Modic changes were recruited as the control group. A retrospective review was performed in 61 patients with Modic changes and 80 controls without Modic changes. The percentage of fatty muscle degeneration was graded by two reviewers using T2-weighted axial images at the L4-L5 level. The system was graded as follows: grade 0, normal; grade I, minimal focal or linear fat deposition; grade II, up to 25%; grade III, 25%-50%; and grade IV, more than 50%. RESULTS: Sixty-one patients with nonspecific LBP and Modic type I or I/II change and 80 patients without Modic changes were evaluated. There was no difference between these groups in terms of age, gender, and BMI distribution. The mean muscle cross-sectional area in the patient and control groups were 1,507.37±410.63 and 1,681.64±379.69. Regarding fatty degeneration, a chi-square test of homogeneity was run, and the two multinomial probability distributions were not equal within the population analyzed. CONCLUSIONS: The novel finding of this investigation is that patients with Modic type I and I/II changes have greater amounts of fatty degeneration in their lumbar paraspinal musculature.

Utility of the claw sign in spine magnetic nuclear resonance with diffusion to differentiate Modic type I changes for degenerative disease versus infection.

BACKGROUND: In 1988, Modic and his colleagues described changes in the subchondral bone marrow of the vertebral plates in patients with degenerative disease or other pathologies, which were observed in the nuclear magnetic resonance (NMR) of the spine and were subdivided into three patterns of signal changes, called Modic type I, Modic type II and Modic type III. The main differential diagnosis of the Modic I changes of the vertebral plates due to degenerative disease in spine NMR, is infection in its early stages. In their study in 2014, Patel and collaborators, using a protocol and the concept of diffusion in spine MRI, were able to demonstrate that by means of the "claw sing", a degenerative disease with Modic type I changes, can be differentiated from an infection in early stages. In this series of cases, the algorithm used by Patel et al. was implemented. METHODS: The clinical records of patients who consulted the emergency department for lumbar pain without clear etiology, between January 1, 2017 and December 31, 2017, were analyzed. Due to axial lumbar pain, subjects were hospitalized and studies were ordered, including contrasted MRI of the lumbosacral spine. Then, with laboratory tests and MRI findings of Modic type I changes, it was not possible to differentiate between degenerative disease vs. spondylodiscitis. Therefore, the algorithm used in the study by Patel and collaborators was applied. RESULTS: There were 13 patients identified with lumbar or dorsal pain over 3 months of evolution, with nonspecific symptoms; 5 patients (38.46%) reported arterial hypertension, 4 patients (30.77%) diabetes mellitus, and 4 patients (30.77%) chronic kidney disease stage V in management with hemodialysis, 3 patients (23.08%) presented immunosuppressive conditions and 3 patients (23.08%) had a history of spinal surgery with instrumentation. All the patients were hospitalized and a lumbosacral and thoracic spine simple MRI was performed with Modic type I changes to perform contrast-enhanced MRI with diffusion and ADC. From the 13 cases studied for low back pain, there were 7 patients (53.85%) with confirmed findings of Modic type I changes due to degenerative disease for presenting claw sign in spinal MRI diffusion and 6 patients (46.15%) Modic type changes I due to infection in the absence of a claw sign in the column MRI diffusion. CONCLUSIONS: Spinal column MRI with diffusion is useful to differentiate patients with type I changes due to degenerative disease with positive claw sign; of patients with type I changes due to infection with absent claw sign. In addition, in patients with compromised renal function, column MRI with diffusion without contrast could be a diagnostic alternative, since it does not require contrast media to confirm infection.

Editorial on two chronic low back pain studies: A major change in surgical management of disc disease?

In two recent publications, the authors' hypothesis was that Modic type 1 changes seen in patients with chronic low back pain and herniated lumbar discs may be attributed to bacterial infection/inflammation. The first study showed that many herniated discs were infected with Proprionibacterium acnes, a common anaerobic skin organism, also found in sarcoidosis, and possibly, arthritic joints. In the second double-blind randomized study, 162 patients with disc herniation and Modic type 1 changes were treated with 100 days of oral Bioclavid (Amoxicillin/Clavulanic acid) vs. placebo; those treated with antibiotics improved in all dimensions (e.g., reduced chronic low back/leg pain, reduced disability). Together, the implications of these studies for spine surgeons and pain practitioners are momentous. If a few weeks of oral antibiotic treatment resolves chronic low back pain, then much currently performed spine surgery (e.g. including internal fixation/fusion), as well as chronic pain management/rehabilitation and psychological strategies may be rendered unnecessary.