Search Results

You are looking at 1 - 4 of 4 items for

  • Author or Editor: Constantin Roder x
Clear All Modify Search
Restricted access

Constantin Roder, Till-Karsten Hauser, Ulrike Ernemann, Marcos Tatagiba, Nadia Khan and Benjamin Bender

OBJECTIVE

The purpose of this study was to evaluate chronological patterns of arterial wall contrast enhancement in contrast-enhanced high-resolution MRI (CE-HR-MRI) in patients with moyamoya disease (MMD).

METHODS

The authors performed a blinded analysis of clinical and imaging data from MMD patients. Data were analyzed chronologically for each patient and the intensity of arterial wall enhancement was correlated with the clinical and imaging-based progression status of the disease.

RESULTS

A total of 31 MMD patients and 61 imaging time points were included. CE-HR-MRI results were available for 56 time points, representing 112 hemispheric analyses. No arterial wall contrast enhancement (grade 1) was seen in 54 (48%) of the analyses, mild enhancement (grade 2) in 24 (21%), moderate enhancement (grade 3) in 15 (13%), and strong (grade 4) mainly concentric arterial wall contrast enhancement in 19 (17%). Grade 4 contrast enhancement was significantly (p < 0.001) associated with clinical disease progression within 6 months (before or after the MRI) compared to grades 1–3, with positive and negative predictive values of 0.8 and 0.88, respectively. Grades 1 and 2 (no contrast enhancement and only mild contrast enhancement) were highly predictive for stable disease (negative predictive value: 0.95).

CONCLUSIONS

A specific chronological increasing and decreasing pattern of arterial wall contrast enhancement associated with “beginning” as well as progression of angiopathy occurs in MMD patients. In clinical practice, CE-HR-MRI of the arterial wall may help to identify patients at risk of new strokes caused by disease progression and hence impel early treatment for future stroke prevention. Understanding of this temporary enhancement of the arterial wall might also bring new insights into the etiology of MMD.

Full access

Constantin Roder, Edyta Charyasz-Leks, Martin Breitkopf, Karlheinz Decker, Ulrike Ernemann, Uwe Klose, Marcos Tatagiba and Sotirios Bisdas

OBJECTIVE

The authors' aim in this paper is to prove the feasibility of resting-state (RS) functional MRI (fMRI) in an intraoperative setting (iRS-fMRI) and to correlate findings with the clinical condition of patients pre- and postoperatively.

METHODS

Twelve patients underwent intraoperative MRI-guided resection of lesions in or directly adjacent to the central region and/or pyramidal tract. Intraoperative RS (iRS)–fMRI was performed pre- and intraoperatively and was correlated with patients' postoperative clinical condition, as well as with intraoperative monitoring results. Independent component analysis (ICA) was used to postprocess the RS-fMRI data concerning the sensorimotor networks, and the mean z-scores were statistically analyzed.

RESULTS

iRS-fMRI in anesthetized patients proved to be feasible and analysis revealed no significant differences in preoperative z-scores between the sensorimotor areas ipsi- and contralateral to the tumor. A significant decrease in z-score (p < 0.01) was seen in patients with new neurological deficits postoperatively. The intraoperative z-score in the hemisphere ipsilateral to the tumor had a significant negative correlation with the degree of paresis immediately after the operation (r = −0.67, p < 0.001) and on the day of discharge from the hospital (r = −0.65, p < 0.001). Receiver operating characteristic curve analysis demonstrated moderate prognostic value of the intraoperative z-score (area under the curve 0.84) for the paresis score at patient discharge.

CONCLUSIONS

The use of iRS-fMRI with ICA-based postprocessing and functional activity mapping is feasible and the results may correlate with clinical parameters, demonstrating a significant negative correlation between the intensity of the iRS-fMRI signal and the postoperative neurological changes.

Free access

Constantin Roder, Martin Breitkopf, MS, Sotirios Bisdas, Rousinelle da Silva Freitas, Artemisia Dimostheni, Martin Ebinger, Markus Wolff, Marcos Tatagiba and Martin U. Schuhmann

OBJECTIVE

Intraoperative MRI (iMRI) is assumed to safely improve the extent of resection (EOR) in patients with gliomas. This study focuses on advantages of this imaging technology in elective low-grade glioma (LGG) surgery in pediatric patients.

METHODS

The surgical results of conventional and 1.5-T iMRI-guided elective LGG surgery in pediatric patients were retrospectively compared. Tumor volumes, general clinical data, EOR according to reference radiology assessment, and progression-free survival (PFS) were analyzed.

RESULTS

Sixty-five patients were included in the study, of whom 34 had undergone conventional surgery before the iMRI unit opened (pre-iMRI period) and 31 had undergone surgery with iMRI guidance (iMRI period). Perioperative data were comparable between the 2 cohorts, apart from larger preoperative tumor volumes in the pre-iMRI period, a difference without statistical significance, and (as expected) significantly longer surgeries in the iMRI group. According to 3-month postoperative MRI studies, an intended complete resection (CR) was achieved in 41% (12 of 29) of the patients in the pre-iMRI period and in 71% (17 of 24) of those in the iMRI period (p = 0.05). Of those cases in which the surgeon was postoperatively convinced that he had successfully achieved CR, this proved to be true in only 50% of cases in the pre-iMRI period but in 81% of cases in the iMRI period (p = 0.055). Residual tumor volumes on 3-month postoperative MRI were significantly smaller in the iMRI cohort (p < 0.03). By continuing the resection of residual tumor after the intraoperative scan (when the surgeon assumed that he had achieved CR), the rate of CR was increased from 30% at the time of the scan to 85% at the 3-month postoperative MRI.

The mean follow-up for the entire study cohort was 36.9 months (3–79 months). Progression-free survival after surgery was noticeably better for the entire iMRI cohort and in iMRI patients with postoperatively assumed CR, but did not quite reach statistical significance. Moreover, PFS was highly significantly better in patients with CRs than in those with incomplete resections (p < 0.001).

CONCLUSIONS

Significantly better surgical results (CR) and PFS were achieved after using iMRI in patients in whom total resections were intended. Therefore, the use of high-field iMRI is strongly recommended for electively planned LGG resections in pediatric patients.

Restricted access

Andrej Paľa, Jan Coburger, Moritz Scherer, Hajrullah Ahmeti, Constantin Roder, Florian Gessler, Christine Jungk, Angelika Scheuerle, Christian Senft, Marcos Tatagiba, Michael Synowitz, Christian Rainer Wirtz, Bernd Schmitz and Andreas W. Unterberg

OBJECTIVE

The level of evidence for adjuvant treatment of diffuse WHO grade II glioma (low-grade glioma, LGG) is low. In so-called “high-risk” patients most centers currently apply an early aggressive adjuvant treatment after surgery. The aim of this assessment was to compare progression-free survival (PFS) and overall survival (OS) in patients receiving radiation therapy (RT) alone, chemotherapy (CT) alone, or a combined/consecutive RT+CT, with patients receiving no primary adjuvant treatment after surgery.

METHODS

Based on a retrospective multicenter cohort of 288 patients (≥ 18 years old) with diffuse WHO grade II gliomas, a subgroup analysis of patients with a confirmed isocitrate dehydrogenase (IDH) mutation was performed. The influence of primary adjuvant treatment after surgery on PFS and OS was assessed using Kaplan-Meier estimates and multivariate Cox regression models, including age (≥ 40 years), complete tumor resection (CTR), recurrent surgery, and astrocytoma versus oligodendroglioma.

RESULTS

One hundred forty-four patients matched the inclusion criteria. Forty patients (27.8%) received adjuvant treatment. The median follow-up duration was 6 years (95% confidence interval 4.8–6.3 years). The median overall PFS was 3.9 years and OS 16.1 years. PFS and OS were significantly longer without adjuvant treatment (p = 0.003). A significant difference in favor of no adjuvant therapy was observed even in high-risk patients (age ≥ 40 years or residual tumor, 3.9 vs 3.1 years, p = 0.025). In the multivariate model (controlled for age, CTR, oligodendroglial diagnosis, and recurrent surgery), patients who received no adjuvant therapy showed a significantly positive influence on PFS (p = 0.030) and OS (p = 0.009) compared to any other adjuvant treatment regimen. This effect was most pronounced if RT+CT was applied (p = 0.004, hazard ratio [HR] 2.7 for PFS, and p = 0.001, HR 20.2 for OS). CTR was independently associated with longer PFS (p = 0.019). Age ≥ 40 years, histopathological diagnosis, and recurrence did not achieve statistical significance.

CONCLUSIONS

In this series of IDH-mutated LGGs, adjuvant treatment with RT, CT with temozolomide (TMZ), or the combination of both showed no significant advantage in terms of PFS and OS. Even in high-risk patients, the authors observed a similar significantly negative impact of adjuvant treatment on PFS and OS. These results underscore the importance of a CTR in LGG. Whether patients ≥ 40 years old should receive adjuvant treatment despite a CTR should be a matter of debate. A potential tumor dedifferentiation by administration of early TMZ, RT, or RT+CT in IDH-mutated LGG should be considered. However, these data are limited by the retrospective study design and the potentially heterogeneous indication for adjuvant treatment.