scholarly journals NI-08 TRIAL AND PROBLEM OF USING ASL IN INTRAOPERATIVE MRI

2019 ◽  
Vol 1 (Supplement_2) ◽  
pp. ii27-ii27
Author(s):  
Jun Nishiyama ◽  
Takuya Yonemochi ◽  
Kazuma Yokota ◽  
Hideki Atsumi ◽  
Takatoshi Sorimachi ◽  
...  

Abstract INTRODUCTION Magnetic resonance perfusion imaging is considered to be available as grading of brain tumor and follow-up of brain treatment. One of the methods, arterial spin labeling (ASL), is a test that is useful for patients with renal impairment and contrast agent allergy and has low invasiveness because it does not use a contrast agent. However, there have been no reports of ASL in intraoperative MRI (iMRI). PURPOSE In this hospital iMRI (1.5T), it was examined whether ASL could be used to evaluate residual tumor in patients under general anesthesia. CASE STUDY A 75-year-old woman with right temporal lobe Glioblastoma. 43-year-old man, left temporal lobe Diffuse astrocytoma. All performed ASL at the time of MRI imaging for navigation before induction of anesthesia just before surgery and iMRI. In all cases, the blood pressure at iMRI was maintained, and Post Label Delay (PLD) calculated the optimal PLD from the carotid artery velocity measured by iMRI, and defined it as 1800–2200 ms, and performed ASL. RESULTS Actually, imaging by iMRI was almost difficult to visualize, and reflux was not recognized not only in the tumor but also in the gray matter. DISCUSSION The blood flow velocity measurement in the internal carotid artery is performed by the phase contrast method by intraoperative MRI, and the CBF decreases because propofol used during the operation decreases the CBF and also the brain metabolism. However, it has been suggested that it is one of the factors that make evaluation with ASL difficult. Although the iMRI of our hospital is 1.5 T, which is also a subject of investigation, it is thought that there is a limit to ASL imaging in the case of general anesthesia with propofol even from the calculated PLD. CONCLUSION ASL in iMRI at our hospital was not useful.

2019 ◽  
Vol 65 (5) ◽  
pp. 721-725
Author(s):  
Elmira Shakirova ◽  
Andrey Panov ◽  
Alevtina Akhmetzyanova ◽  
Aliya Gafiullina ◽  
L. Ibragimova ◽  
...  

Aims: Chemoradiation (CRT) is the standard treatment for locally advanced cervical cancer (LACC). However part of the patients develop recurrence during the first year after treatment despite good visible effect at the first follow-up. The role of completion surgery after radiotherapy (RT) is still debated. A number of papers have showed that up to 60% of patients have residual tumor after CRT and RT. But such a surgery is not widely recommended because of increased morbidity of the treatment. The aim of this study was to assess the results of surgery after radiotherapy of LACC. Method: We retrospectively evaluated data on 86 patients with cervical cancer IB - IIIB stages (mostly stage IIB) who underwent surgery in different modalities after CRT and RT with good clinical response in our department in 2015-2018. Results: When small asymptomatic residual disease was detected early after radiotherapy radical hysterectomy was feasible in most of the cases. Patients with clinical manifestation of recurrence had very poor prognosis. Surgery of recurrent cervical cancer sufficiently deteriorates quality of life, even if possible. Conclusion: Thorough examination with adding MRI imaging after initial treatment of cervical cancer needed to identify patients who may benefit from adjuvant hysterectomy.


2020 ◽  
Vol 2 (Supplement_3) ◽  
pp. ii14-ii14
Author(s):  
Takaaki Beppu ◽  
Yuichi Sato ◽  
Toshiaki Sasaki ◽  
Kazunori Terasaki ◽  
Kuniaki Ogasawara

Abstract Background: The aim was to clarify whether positron emission tomography with 11C-methyl-L-methionine (met-PET) is useful to decide on discontinuation of TMZ-adjuvant therapy in patients with residual diffuse astrocytic tumor. Methods: Subjects were 44 patients with residual tumor comprising 17 with IDH1-mutant diffuse astrocytoma (DA), 13 with IDH1-mutant anaplastic astrocytoma (AA), and 14 with IDH1-wild glioblastoma (GB). All patients received TMZ-adjuvant chemotherapy (median, 12 courses), and whether to discontinue or continue TMZ-adjuvant chemotherapy was decided on the basis of the tumor-to-normal ratio in standardized uptake value from met-PET (T/N); patients with T/N < 1.6 immediately discontinued TMZ, and patients with T/N > 1.6 were either to continued or discontinued TMZ. Progression-free survival (PFS) was compared between patients with T/N > 1.6 and T/N < 1.6 in each tumor type. Median observation period was 434 days after met-PET scanning. Results: The number of patient who underwent recurrence was 10 in DA, 7 in AA, and 11 in GB. All patients showing T/N > 1.6 underwent tumor recurrence. PFS was significantly longer in patients with T/N < 1.6 than T/N > 1.6 in DA and AA (p < 0.01 in both types), but was no significant difference between 2 groups in GB (p = 0.06). Sixteen of 17 patients (94%) in DA and AA showed recurrence from residual tumor, whereas 4 of 11 patients (36%) in GB showed recurrent tumor at remote regions which were different from residual tumor. Conclusions: The present study suggested that met-PET is beneficial to decide to discontinue adjuvant chemotherapy with TMZ in patients with residual tumors of DA and AA, but not useful for patients with GB. Reasons for unsuccessful results in GB might have been small sample size, failure of establishing the cut off value in T/N, recurrences at remote regions where not be assessed by met-PET.


Nanomaterials ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1235
Author(s):  
Xiaohui Nan ◽  
Wenjia Lai ◽  
Dan Li ◽  
Jiesheng Tian ◽  
Zhiyuan Hu ◽  
...  

Derived from magnetotactic bacteria (MTB), magnetosomes consist of magnetite crystals enclosed within a lipid bilayer membrane and are known to possess advantages over artificially synthesized nanoparticles because of the narrow size distribution, uniform morphology, high purity and crystallinity, single magnetic domain, good biocompatibility, and easy surface modification. These unique properties have increasingly attracted researchers to apply bacterial magnetosomes (BMs) in the fields of biology and medicine as MRI imaging contrast agents. Due to the concern of biosafety, a long-term follow-up of the distribution and clearance of BMs after entering the body is necessary. In this study, we tracked changes of BMs in major organs of mice up to 135 days after intravenous injection using a combination of several techniques. We not only confirmed the liver as the well-known targeted organs of BMs, but also found that BMs accumulated in the spleen. Besides, two major elimination paths, as well as the approximate length of time for BMs to be cleared from the mice, were revealed. Together, the results not only confirm that BMs have high biocompatibility, but also provide a long-term in-vivo assessment which may further help to forward the clinical applications of BMs as an MRI contrast agent.


2018 ◽  
Vol 47 (2) ◽  
pp. 682-688 ◽  
Author(s):  
Songhe Shen ◽  
Xiongjing Jiang ◽  
Hui Dong ◽  
Meng Peng ◽  
Zhixue Wang ◽  
...  

Objective This study was performed to explore the effect of the aortic arch type on technical indicators in patients undergoing carotid artery stenting (CAS). Methods The data of 224 consecutive patients who underwent unilateral CAS from January 2011 to December 2012 were retrospectively analyzed. The requirement for placement of the guiding catheter into the common carotid artery with assistance of an angiographic catheter, fluoroscopy time, contrast agent dose, and adverse events were recorded. Results The fluoroscopy time was significantly longer and the contrast agent dose was significantly higher in patients with Type III than Type I and II arches. Significantly more patients with Type III than Type I and II arches required placement of the guiding catheter with assistance of an angiographic catheter (46.2% vs. 15.0%, respectively). The procedural success rate was significantly lower in patients with Type III than Type I and II arches (96.2% vs. 100.0%, respectively). The incidence of death, myocardial infarction, and all types of stroke was significantly higher in patients with Type III than Type I and II arches (7.7% vs. 1.7%, respectively). Conclusions The aortic arch type is an important influential factor in CAS. Type III arches are associated with more difficulties and complications.


F1000Research ◽  
2014 ◽  
Vol 2 ◽  
pp. 252
Author(s):  
Rachael A Panizzo ◽  
David G Gadian ◽  
Jane C Sowden ◽  
Jack A Wells ◽  
Mark F Lythgoe ◽  
...  

Efficacy of neural stem/progenitor cell (NPC) therapies after cerebral ischaemia could be better evaluated by monitoring in vivo migration and distribution of cells post-engraftment in parallel with analysis of lesion volume and functional recovery. Magnetic resonance imaging (MRI) is ideally placed to achieve this, but still poses several challenges. We show that combining the ferumoxide MRI contrast agent Endorem with protamine sulphate (FePro) improves iron oxide uptake in cells compared to Endorem alone and is non-toxic. Hence FePro complex is a better contrast agent than Endorem for monitoring NPCs. FePro complex-labelled NPCs proliferated and differentiated normally in vitro, and upon grafting into the brain 48 hours post-ischaemia they were detected in vivo by MRI. Imaging over four weeks showed the development of a confounding endogenous hypointense contrast evolution at later timepoints within the lesioned tissue. This was at least partly due to accumulation within the lesion of macrophages and endogenous iron. Neither significant NPC migration, assessed by MRI and histologically, nor a reduction in the ischaemic lesion volume was observed in NPC-grafted brains.  Crucially, while MRI provides reliable information on engrafted cell location early after an ischaemic insult, pathophysiological changes to ischaemic lesions can interfere with cellular imaging at later timepoints.


2021 ◽  
Vol 50 (1) ◽  
pp. E12
Author(s):  
Monika Lauer ◽  
Arne Lauer ◽  
Se-Jong You ◽  
Sara Kluge ◽  
Elke Hattingen ◽  
...  

OBJECTIVEIntraoperative MRI with Gd-based contrast agent (GBCA) improves the extent of resection of contrast-enhancing brain tumors. Signal changes of CSF due to perioperative GBCA leakage in the subarachnoid space have been reported. However, although GBCA potentially exhibits neurotoxic effects, so far no associated complications have been described. In this case series, the authors report a single-center cohort of patients with subarachnoid GBCA extravasation after intraoperative MRI and discuss potential neurotoxic complications and potential ways of avoiding them.METHODSAll patients with CSF signal increase on unenhanced T1-weighted and FLAIR images on postoperative MRI, who had previously undergone tumor resection with use of intraoperative MRI, were retrospectively included and compared with a control cohort. The control group was matched in age, tumor characteristics, and extent of resection; comparisons were made regarding postoperative seizures and ICU stay. A subgroup with initially diagnosed malignant glioma was additionally analyzed for potential delay of initiation of adjuvant treatment and overall survival.RESULTSSeven patients with postoperative GBCA accumulation in the subarachnoid space were identified; 5 presented with focal seizures and altered mental status postoperatively. Poor patient condition led to extended ICU stay and prolonged delay of the initiation of adjuvant treatment in patients with newly diagnosed malignant glioma. Overall survival was reduced compared to the matched control group.CONCLUSIONSThe results suggest that there might be a risk of neurotoxic complications if GBCA that is intravenously applied during neurosurgery leaks into the subarachnoid space. Patients with highly vascularized tumors with intraoperative bleeding seem to be especially at risk for GBCA accumulation and neurotoxic complications. Therefore, awareness of the potential risk of complicating GBCA leakage is mandatory in the application of intraoperative GBCA.


2018 ◽  
Vol 65 (1) ◽  
pp. 151-162
Author(s):  
Arkadiusz Szarmach ◽  
Mariusz Kaszubowski ◽  
Agnieszka Sabisz ◽  
Andrzej F Frydrychowski ◽  
Grzegorz Halena ◽  
...  

The aim of this study was to assess regional perfusion at baseline and regional cerebrovascular resistance (CVR) to delayed acetazolamide challenge in subjects with chronic carotid artery stenosis.Sixteen patients (ten males) aged 70.94±7.71 with carotid artery stenosis ≥90% on the ipsilateral side and ≤50% on the contralateral side were enrolled into the study. In all patients, two computed tomography perfusion examinations were carried out; the first was performed before acetazolamide administration and the second 60 minutes after injection.The differences between mean values were examined by paired two-sample t-test and alternative nonparametric Wilcoxon’s test. Normality assumption was examined using W Shapiro-Wilk test.The lowest resting-state cerebral blood flow (CBF) was observed in white matter (ipsilateral side: 18.4±6.2; contralateral side: 19.3±6.6) and brainstem (ipsilateral side: 27.8±8.5;  contralateral side: 29.1±10.8). Grey matter (cerebral cortex) resting state CBF was below the normal value for subjects of this age: frontal lobe – ipsilateral side: 30.4±7.0, contralateral side: 33.7±7.1; parietal lobe – ipsilateral side: 36.4±11.3, contralateral side: 42.7±9.9; temporal lobe – ipsilateral side: 32.5±8.6, contralateral side: 39.4±10.8; occipital lobe – ipsilateral side: 24.0±6.0, contralateral side: 26.4±6.6). The highest resting state CBF was observed in the insula (ipsilateral side: 49.2±17.4; contralateral side: 55.3±18.4). A relatively high resting state CBF was also recorded in the thalamus (ipsilateral side: 39.7±16.9; contralateral side: 41.7±14.1) and cerebellum (ipsilateral side: 41.4±12.2; contralateral side: 38.1±11.3). The highest CVR was observed in temporal lobe cortex (ipsilateral side: +27.1%; contralateral side: +26.1%) and cerebellum (ipsilateral side: +27.0%; contralateral side: +34.6%). The lowest CVR was recorded in brain stem (ipsilateral side: +20.2%; contralateral side: +22.2%) and white matter (ipsilateral side: +18.1%; contralateral side: +18.3%). All CBF values were provided in milliliters of blood per minute per 100 g of brain tissue [ml/100g/min]. Resting state circulation in subjects with carotid artery stenosis is low in all analysed structures with the exception of insula and cerebellum. Acetazolamide challenge yields relatively uniform response in both hemispheres in the investigated population.Grey matter is more reactive to acetazolamide challenge than white matter or brainstem.


2008 ◽  
Vol 62 (suppl_5) ◽  
pp. ONS481-ONS489 ◽  
Author(s):  
Martin Ortler ◽  
Gerlig Widmann ◽  
Eugen Trinka ◽  
Thomas Fiegele ◽  
Wilhelm Eisner ◽  
...  

Abstract Objective: Semi-invasive foramen ovale electrodes (FOEs) are used as an alternative to invasive recording techniques in the presurgical evaluation of patients with temporal lobe epilepsy. To maximize patient safety and interventional success, frameless stereotactic FOE placement by use of a variation of an upper jaw fixation device with an external fiducial frame, in combination with an aiming device and standard navigation software, was evaluated by the Innsbruck Epilepsy Surgery Program. Methods: Patients were immobilized noninvasively with the Vogele-Bale-Hohner headholder (Medical Intelligence GmbH, Schwabmünchen, Germany) to plan computed tomography and surgery. Frameless stereotactic cannulation of the foramen and intracranial electrode placement were achieved with the help of an aiming device mounted to the base plate of the headholder. Ease of applicability, safety, and results obtained with foramen ovale recording were investigated. Results: Twenty-six FOEs were placed in 13 patients under general anesthesia. The foramen ovale was successfully cannulated in all patients. One patient reported transient painful mastication after the procedure as a complication attributable to use of the Vogele-Bale-Hohner mouthpiece. In one patient, a persistent slight buccal hypesthesia was present 3 months after the procedure. To pass the foramen, slight adjustments in the needle position had to be made in 10 sides (38.4%). To place the intracranial electrodes, adjustments were necessary six times (23.7%). An entirely new path had to be planned once (3.8%). Seizure recording provided conclusive information in all patients (100%). Outcome in operated patients was Engel Class Ia in six patients, Class IId in one patient, Class IIb in one patient, and Class IVa in one patient (minimum follow-up, 6 mo). Conclusion: The Vogele-Bale-Hohner headholder combined with an external registration frame eliminates the need for invasive head clamp fixation. FOE placement can be planned “offline” and performed under general anesthesia later. This can be valuable in patients with distorted anatomy and/or small foramina or in patients not able to undergo the procedure under sedation. Results are satisfactory with regard to patient safety, patient comfort, predictability, and reproducibility. FOEs supported further treatment decisions in all patients.


2019 ◽  
Vol 21 (Supplement_6) ◽  
pp. vi162-vi162
Author(s):  
Keisuke Miyake ◽  
Daisuke Ogawa ◽  
Masaki Okada ◽  
Tetsuhiro Hatakeyama ◽  
Takashi Tamiya

Abstract OBJECTIVE Neuronavigation systems with magnetic resonance imaging (MRI) and positron emission tomography (PET) imaging (methionine [MET], fluorothymidine [FLT], and fluoromisonidazole [FMISO]) are routinely used in glioblastoma surgery. Residual tumor identified using intraoperative MRI (IoMRI) or 5-aminolevulinic acid (5-ALA) fluorescence is removed. Neoadjuvant bevacizumab therapy is offered to patients with low Karnovsky performance status (KPS) or with tumors in eloquent regions. We evaluated the usefulness of neoadjuvant bevacizumab therapy. METHODS Twelve patients with glioblastoma with low KPS or tumors in eloquent regions on multiple PET and IoMRI evaluations were enrolled between January 2016 and April 2019. Six had received neoadjuvant bevacizumab before surgery; six had not. Postsurgical 5-ALA fluorescence (strong, vague, and none) tumor extraction rate, residual volume on MRI and PET imaging, and prognosis in the patients with and without bevacizumab were compared. RESULTS In patients with bevacizumab adjuvant therapy, the KPS scores immediately prior to surgery were 90 in 3 cases, 80 in 2, and 70 in 1. The scores in patients without bevacizumab were 50 in 2 and 40 in 4. The 5-ALA fluorescence in patients with bevacizumab was vague in one and none in five. Vague fluorescence was noted in all six patients without bevacizumab. Tumor extraction rates in patients with vs. those without bevacizumab were 97.6% vs. 91.5% by T1-Gd, 95.4% vs. 99.9% by MET, 96.2% vs. 90.2% by FLT, and 97% vs. 92% by FMISO. Corresponding residual volumes (ml) were (0.6 vs. 1.7) for T1-Gd, 1.2 vs. 2.9 for MET, 1.0 vs. 2.1 for FLT, and 0.5 vs. 1.1 for. FLT. Median progression free survival (PFS) was 10.1 vs. 4.9 months; median overall survival (OS) was 15.7 vs. 13.3 months. CONCLUSIONS Neoadjuvant bevacizumab therapy improved KPS at the time of surgery, increased extraction rate, reduced residual tumor volume, and improved PFS and OS prognosis.


2016 ◽  
Vol 40 (3) ◽  
pp. E4 ◽  
Author(s):  
Moritz Scherer ◽  
Christine Jungk ◽  
Alexander Younsi ◽  
Philipp Kickingereder ◽  
Simon Müller ◽  
...  

OBJECTIVE In this analysis, the authors sought to identify variables triggering an additional resection (AR) and determining residual intraoperative tumor volume in 1.5-T intraoperative MRI (iMRI)-guided glioma resections. METHODS A consecutive case series of 224 supratentorial glioma resections (WHO Grades I–IV) from a prospective iMRI registry (inclusion dates January 2011–April 2013) was examined with univariate and multiple regression models including volumetric data, tumor-related, and surgeon-related factors. The surgeon's expectation of an AR, in response to a questionnaire completed prior to iMRI, was evaluated using contingency analysis. A machine-learning prediction model was applied to consider if anticipation of intraoperative findings permits preoperative identification of ideal iMRI cases. RESULTS An AR was performed in 70% of cases after iMRI, but did not translate into an accumulated risk for neurological morbidity after surgery (p = 0.77 for deficits in cases with AR vs no AR). New severe persistent deficits occurred in 6.7% of patients. Initial tumor volume determined frequency of ARs and was independently correlated with larger tumor remnants delineated on iMRI (p < 0.0001). Larger iMRI volume was further associated with eloquent location (p = 0.010) and recurrent tumors (p < 0.0001), and with WHO grade (p = 0.0113). Greater surgical experience had no significant influence on the course of surgery. The surgeon's capability of ruling out an AR prior to iMRI turned out to incorporate guesswork (negative predictive value 43.6%). In a prediction model, AR could only be anticipated with 65% accuracy after integration of confounding variables. CONCLUSIONS Routine use of iMRI in glioma surgery is a safe and reliable method for resection guidance and is characterized by frequent ARs after scanning. Tumor-related factors were identified that influenced the course of surgery and intraoperative decision-making, and iMRI had a common value for surgeons of all experience levels. Commonly, the subjective intraoperative impression of the extent of resection had to be revised after iMRI review, which underscores the manifold potential of iMRI guidance. In combination with the failure to identify ideal iMRI cases preoperatively, this study supports a generous, tumor-oriented rather than surgeon-oriented indication for iMRI in glioma surgery.


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