Dual-Use Intraoperative MRI in Glioblastoma Surgery: Results of Resection, Histopathologic Assessment, and Surgical Site Infections.

BACKGROUND: To achieve maximal resection in glioblastoma (GBM) surgery, intraoperative imaging is important. An intraoperative magnetic resonance imaging (iMRI) suite used for both diagnostic and intraoperative imaging is considered being a reasonable concept for modern hospital management. It is still discussed if the dual use increases the risk of surgical site infections (SSI). This article assesses the rate of gross total resection (GTR), extent of resection (EOR), and histopathology after iMRI-guided resections in patients with GBM. The rate of surgical site infections (SSIs) is evaluated. METHODS: In all, 79 patients with GBM were operated on with iMRI. Additional resection was performed if iMRI depicted contrast enhancing tissue suggestive of residual tumor. GTR and EOR were determined by segmentation and volumetric analysis of the MR images. SSIs and the role of intravenous only or intravenous plus intrathecal antibiotics were evaluated. Statistical analysis was performed to detect the sensitivity, specificity, positive predictive value, and negative predictive value of iMRI-guided extended resections. Pearson's two-tailed chi-square test was performed to evaluate the rates of GTR and variables associated with SSI. RESULTS: GTR was achieved in 59 patients (74.68%). Rate of GTR was 35.44% before iMRI and additional resections (p < 0.0001). Mean EOR was 96.27%. Positive predictive value for tumor cells in the additionally resected tissue was 88.6%, negative predictive value was 100%, sensitivity was 100%, and specificity was 70. 6%. Rate of SSIs was 5.06% (n = 4). Two superficial SSIs, one subdural empyema and one cerebritis, were seen. SSI rates with parenteral only and additional intrathecal antibiotics were 0% and 8%, respectively (p = 0.133). CONCLUSION: Increase of extent of tumor resection using iMRI is evident. SSI rate is within the normal range of neurosurgical procedures. A dual-use iMRI suite is a safe concept.

Accuracy of High-Field Intraoperative MRI in the Detectability of Residual Tumor in Glioma Grade IV Resections.

Objective To assess the sensitivity/specificity of tumor detection by T1 contrast enhancement in intraoperative MRI (ioMRI) in comparison to histopathological assessment as the gold standard in patients receiving surgical resection of grade IV glioblastoma. Materials and Methods 68 patients with a primary or a recurrent glioblastoma scheduled for surgery including fluorescence guidance and neuronavigation were included (mean age: 59 years, 26 female, 42 male patients). The ioMRI after the first resection included transverse FLAIR, DWI, T2-FFE and T1 - 3 d FFE +/- GD-DPTA. The second resection was performed whenever residual contrast-enhancing tissue was detected on ioMRI. Resected tissue samples were histopathologically evaluated (gold standard). Additionally, we evaluated the early postoperative MRI scan acquired within 48 h post-OP for remaining enhancing tissue and compared them with the ioMRI scan. Results In 43 patients ioMRI indicated residual tumorous tissue, which could be confirmed in the histological specimens of the second resection. In 16 (4 with recurrent, 12 with primary glioblastoma) cases, ioMRI revealed truly negative results without residual tumor and follow-up MRI confirmed complete resection. In 7 cases (3 with recurrent, 4 with primary glioblastoma) ioMRI revealed a suspicious result without tumorous tissue in the histopathological workup. In 2 (1 for each group) patients, residual tumorous tissue was detected in spite of negative ioMRI. IoMRI had a sensitivity of 95 % (94 % recurrent and 96 % for primary glioblastoma) and a specificity of 69.5 % (57 % and 75 %, respectively). The positive predictive value was 86 % (84 % for recurrent and 87 % for primary glioblastoma), and the negative predictive value was 88 % (80 % and 92 %, respectively). Conclusion ioMRI is effective for detecting remaining tumorous tissue after glioma resection. However, scars and leakage of contrast agent can be misleading and limit specificity. Key points · Intraoperative MRI (ioMRI) presents with a high sensitivity for residual contrast-enhancing tumorous tissue during glioma resection.. · Contrast leakage due to bleeding and scars with reactive contrast enhancement can cause possible misleading artifacts in ioMRI, leading to a limited specificity of ioMRI.. · Bleeding control in glioma resection is crucial for successful usage of ioMRO for glioma resection.. Citation Format · Heßelmann V, Mager A, Goetz C et al. Accuracy of High-Field Intraoperative MRI in the Detectability of Residual Tumor in Glioma Grade IV Resections. Fortschr Röntgenstr 2017; 189: 519 - 526.

Role of whole-body magnetic resonance imaging in diagnosing early spondyloarthritis.

Ankylosing spondylitis is the prototypical spondyloarthritis. Early diagnosis has gained clinical importance with the advent of new therapeutic options such as TNF-alpha inhibitors, which can dramatically improve clinical outcome when initiated early. Whole-body MRI can contribute important diagnostic information for detecting early forms of spondyloarthritis because it enables evaluation of all important joints that may be involved in the disease process as a one-stop shop modality. MRI allows much more accurate diagnostic evaluation of the thoracic spine, which is affected in the majority of patients. This article provides an overview of the use of whole-body magnetic resonance imaging (MRI) in the spondyloarthritides. The recommendations given reflect the most recent scientific data and expert opinions. The focus of this review is on MRI findings at both the axial and the appendicular skeleton and the technical feasibility of whole-body MRI in the clinical setting.