Heterogeneous motor BOLD-fMRI responses in brain areas exhibiting negative BOLD cerebrovascular reactivity indicate that steal phenomenon does not always result from exhausted cerebrovascular reserve capacity.

INTRODUCTION: Brain areas exhibiting negative blood oxygenation-level dependent cerebrovascular reactivity (BOLD-CVR) responses to carbon dioxide (CO2) are thought to suffer from a completely exhausted autoregulatory cerebrovascular reserve capacity and exhibit vascular steal phenomenon. If this assumption is correct, the presence of vascular steal phenomenon should subsequently result in an equal negative fMRI signal response during a motor-task based BOLD-fMRI study (increase in metabolism without an increase in cerebral blood flow due to exhausted reserve capacity) in otherwise functional brain tissue. To investigate this premise, the aim of this study was to further investigate motor-task based BOLD-fMRI signal responses in brain areas exhibiting negative BOLD-CVR. MATERIAL AND METHODS: Seventy-one datasets of patients with cerebrovascular steno-occlusive disease without motor defects, who underwent a CO2-calibrated motor task-based BOLD-fMRI study with a fingertapping paradigm and a subsequent BOLD-CVR study with a precisely controlled CO2-challenge during the same MRI examination, were included. We compared BOLD-fMRI signal responses in the bilateral pre- and postcentral gyri - i.e. Region of Interest (ROI) with the corresponding BOLD-CVR in this ROI. The ROI was determined using a second level group analysis of the BOLD-fMRI task study of 42 healthy individuals undergoing the same study protocol. RESULTS: An overall decrease in BOLD-CVR was associated with a decrease in BOLD-fMRI signal response within the ROI. For patients exhibiting negative BOLD-CVR, we found both positive and negative motor-task based BOLD-fMRI signal responses. CONCLUSION: We show that the presence of negative BOLD-CVR responses to CO2 is associated with heterogeneous motor task-based BOLD-fMRI signal responses, where some patients show -more presumed- negative BOLD-fMRI signal responses, while other patient showed positive BOLD-fMRI signal responses. This finding may indicate that the autoregulatory vasodilatory reserve capacity does not always need to be completely exhausted for vascular steal phenomenon to occur.

[Lung Cancer Surgery for Severe COPD with Emphysema: Tumor Resection with Improvement of Lung Function]. / Lungenkrebschirurgie bei schwerer COPD mit Emphysem: Tumorresektion mit Verbesserung der Lungenfunktion.

Lung Cancer Surgery for Severe COPD with Emphysema: Tumor Resection with Improvement of Lung Function Abstract. The golden standard for the therapy of early stage non-small cell lung cancer consists of surgical resection, usually performed as lobectomy or segmentectomy. These procedures demand a certain operability, including certain lung functional reserves. Patients with COPD and emphysema usually have lung function values far below that. Nevertheless, these patients can be offered treatmentif at the same time they qualify for concomitant lung volume reduction surgery (LVRS). LVRS with simultaneous tumor resection can consolidate the diagnosis, provide definite histology, correct staging, and thorough tumor resection might even improve the postoperative lung function. As with all patients with a (possible) diagnosis of cancer, the indication must be discussed in an interdiscplinary tumor board.

Failure of diffusion-weighted imaging in intraoperative 3 Tesla MRI to identify hyperacute strokes during glioma surgery.

Intraoperatively acquired diffusion-weighted imaging (DWI) sequences in cranial tumor surgery are used for early detection of ischemic brain injuries, which could result in impaired neurological outcome and their presence might thus influence the neurosurgeon's decision on further resection. The phenomenon of false-negative DWI findings in intraoperative magnetic resonance imaging (ioMRI) has only been reported in single cases and therefore yet needs to be further analyzed. This retrospective single-center study's objective was the identification and characterization of false-negative DWI findings in ioMRI with new or enlarged ischemic areas on postoperative MRI (poMRI). Out of 225 cranial tumor surgeries with intraoperative DWI sequences, 16 cases with no additional resection after ioMRI and available in-time poMRI (< 14 days) were identified. Of these, a total of 12 cases showed false-negative DWI in ioMRI (75%). The most frequent tumor types were oligodendrogliomas and glioblastomas (4 each). In 5/12 cases (41.7%), an ischemic area was already present in ioMRI, however, volumetrically increased in poMRI (mean infarct growth + 2.1 cm3; 0.48-3.6), whereas 7 cases (58.3%) harbored totally new infarcts on poMRI (mean infarct volume 0.77 cm3; 0.05-1.93). With this study we provide the most comprehensive series of false-negative DWI findings in ioMRI that were not followed by additional resection. Our study underlines the limitations of intraoperative DWI sequences for the detection and size-estimation of hyperacute infarction. The awareness of this phenomenon is crucial for any neurosurgeon utilizing ioMRI.

Increased Ipsilateral Posterior Cerebral Artery P2-Segment Flow Velocity Predicts Hemodynamic Impairment.

BACKGROUND AND PURPOSE: Increased Transcranial Doppler flow velocity in the ipsilateral P2-segment of the posterior cerebral artery (PCA-P2: cm/second) is associated with recurrent cerebrovascular events in patients with unilateral internal carotid artery occlusion. However, its predictive value and correlation with hemodynamic impairment in an overall stroke patient cohort remains to be determined. METHODS: Transcranial doppler PCA-P2 flow velocity was measured in 88 patients with symptomatic unilateral steno-occlusive disease who also underwent blood oxygenation-level dependent cerebrovascular reactivity imaging (blood oxygenation-level dependent [BOLD]-cerebrovascular reactivity [CVR]). A multivariate linear regression was used to evaluate the independent correlation between the ipsilateral PCA-P2 flow velocity measurements and hemispheric BOLD-CVR. Follow-up BOLD-CVR imaging data, available in 25 patients, were used to evaluate the temporal evolution of the BOLD-CVR and PCA-P2 flow velocity association using a mixed-effect model. Furthermore, a transcranial doppler cutoff for hemodynamic failure stage 2 was determined. RESULTS: The ipsilateral systolic PCA-P2 flow velocity strongly correlated with hemispheric BOLD-CVR (R=0.79; R2=0.61), which remained unchanged when evaluating the follow-up data. Using a PCA-P2 systolic flow velocity cutoff value of 85 cm/second, patients with BOLD-CVR based hemodynamic failure stage 2 were diagnosed with an area under the curve of 95. CONCLUSIONS: In patients with symptomatic unilateral steno-occlusive disease, increased ipsilateral transcranial doppler PCA-P2 systolic flow velocity independently correlates with BOLD-CVR based hemodynamic failure. A cutoff value of 85 cm/second appears to indicate hemodynamic failure stage 2, but this finding needs to be validated in an independent patient cohort.

Crossed Cerebellar Diaschisis in Patients with Diffuse Glioma Is Associated with Impaired Supratentorial Cerebrovascular Reactivity and Worse Clinical Outcome.

Crossed cerebellar diaschisis (CCD) can be associated with impaired cerebrovascular reactivity (CVR) and poor clinical outcome, but whether this holds true for patients with diffuse glioma is unknown. With blood oxygenation level-dependent (BOLD)-CVR imaging, we determined the presence of CCD in patients with diffuse glioma and investigated its relationship with cerebrovascular reactivity and clinical outcome. For eighteen enrolled subjects (nineteen datasets) with diffuse glioma, CCD was deferred from BOLD-CVR using a predetermined cerebellar asymmetry index (CAI) cutoff value of 6.0%. A FET-PET study was done as a verification of the CCD diagnosis. BOLD-CVR values as well as clinical performance scores (i.e., Karnofsky performance score (KPS), disability rating scale (DRS), and modified Rankin scale (mRS)) by BOLD-CVR scan at 3-month clinical follow-up were assessed and compared for the CCD-positive and CCD-negative group. CCD was present in 26.3% of subjects and strongly associated with impaired BOLD-CVR of the affected (i.e., the hemisphere harboring the glioma) and unaffected supratentorial hemisphere (CCD(+) vs. CCD(-): 0.08 ± 0.11 vs. 0.18 ± 0.04; p = 0.007 and 0.08 ± 0.12 vs. 0.19 ± 0.04; p = 0.007, respectively). This finding was independent of tumor volume (p = 0.48). Furthermore, poorer initial (by scan) clinical performance scores at follow-up were found for the CCD(+) group. The presence of crossed cerebellar diaschisis in patients with diffuse glioma is associated with impaired supratentorial cerebrovascular reactivity and worse clinical outcome.

The appearance of joint manifestations in the Swiss inflammatory bowel disease cohort.

BACKGROUND/AIMS: Extraintestinal manifestations (EIM) involving joints, skin, eyes and liver represent an important problem in the treatment of IBD patients. The aim of this study was to identify factors that are associated with the occurrence of joint EIM and therefore allow an early diagnosis and guide medical treatment. METHODS: We studied clinical and epidemiological data from 3298 patients included in the Swiss IBD Cohort Study (SIBDCS), 1860 suffered from Crohn's disease (CD) and 1438 from ulcerative colitis or IBD unclassified (UC/IBDU). RESULTS: We found female gender as well as a longer disease duration and activity (specified as CDAI or MTWAI, respectively) to be related to the appearance of arthritis/arthralgia, but also sacroiliitis/ankylosing spondylitis in IBD patients. IBD patients with arthritis/arthralgia or sacroiliitis/ankylosing spondylitis were more often treated with anti-TNF and patients with arthritis/arthralgia underwent more often IBD-related surgeries. We revealed that eye or skin EIM were more frequent in patients with arthritis/arthralgia or sacroiliitis/ankylosing spondylitis. In multivariate analysis, we confirmed female gender, longer disease duration, IBD-related surgery, presence of other EIM and treatment with anti-TNF to be independent risk factors for the onset of arthritis/arthralgia in CD and UC/IBDU patients. CONCLUSION: In this study, we demonstrated that markers for a more severe disease course were associated with the onset of joint EIM in IBD patients. Our data suggest that in particular females under anti-TNF treatment and patients suffering from non-joint and/or IBD-related surgery should be close and carefully monitored for presence of arthritis or sacroiliitis/ankylosing spondylitis.