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A technique to localize a radiological target on the head convexity fast and with acceptable precision is sufficient for surgeries of superficial intracranial lesions, and of help in the setting of emergency surgery, computer navigation breakdown, limited resources and education. We present a caliper technique based on fundamental geometry, with inexpensive and globally available tools (conventional CT or MRI image viewer, calculator, caliper). The distances of the radiological target from twodoi:10.1371/journal.pone.0251023 pmid:34014940 pmcid:PMC8136664 fatcat:32ho7sllavcrhce47du5ikd3ca
more »... andmarks (nasion and porus acusticus externus) are assessed with an image viewer and Pythagoras' theorem. The two distances are then marked around the landmarks onto the head of the patient with help of a caliper. The intersection defines the target. We tested the technique in a saw bone skull model and afterwards in the operating room. Convexity targets were localized with the caliper navigation technique and then with computer navigation as ground truth. In the saw bone model, the mean offset between the caliper navigated target and the real target was 2.9 ± 2.8 mm, 95% CI (1.6 mm; 4.2 mm). The mean offset between computer navigated target and real target was 1.6 ± 0.9 mm, 95% CI (1.2 mm; 2 mm) (ns). In 15 patients undergoing navigated cranial procedures, 100 targets were assessed in reference to computer navigation. The mean offset of the caliper navigation was 11 ± 5.2 mm, 95% CI (9.9 mm; 12 mm). This is a low-tech approach for translation of a radiological target to the patient's head in short time and with globally available inexpensive tools, with satisfying precision for many procedures.
Wir stellen eine neue Möglichkeit zur dreidimensionalen, präoperativen Planung vor, die nicht nur die Planung von minimalinvasiven Zugangswegen zur Wirbelsäule, sondern darüber hinaus auch eine 3D Modellierung von Instrumenten und die präoperative virtuelle Platzierung von realen Implantaten erlauben soll. Wir testeten diese Vorgehensweise erstmals im Rahmen des Débridement bei einer Patientin mit Spondylodiscitis.dblp:conf/curac/KosterhonGSCKAG12 fatcat:5wxllcjyqffztfjita6xpgamfi
Seit 2004 wird zur dreidimensionalen OP-Planung in der Mainzer Neurochirurgie das Dextroscope-System genutzt, um neurochirurgische Eingriffe durch Optimierung der Zugangswege und Vorgehensweisen sicherer und schonender durchführen zu können. Hierzu werden zweidimensionale Schichtbildaufnahmen fusioniert. Weltweit werden mittlerweile in den Operationssälen nahezu jeder größeren neurochirurgischen Abteilung Navigationsgeräte eingesetzt, die dem Chirurgen intraoperativ die Orientierungdblp:conf/curac/SchwandtKAKSG12 fatcat:6p6wb35xm5fyhkwv76op6d7g6y
more »... Auch diese Geräte verrechnen zweidimensionale Schichtbildaufnahmen und ermöglichen in diesen die Darstellung der exakten Position von OP-Instrumenten. Da es leider bislang nicht möglich war, die mit dem Dextroscope-System erstellten 3D-Planungsdaten zur intraoperativen Navigation zu nutzen, unternahmen wir nun erste Schritte, um mit präoperativ dreidimensional erstellten Planungsdaten intraoperativ dreidimensional navigieren zu können.
The field of radiomics is rapidly expanding and gaining a valuable role in neuro-oncology. The possibilities related to the use of radiomic analysis, such as distinguishing types of malignancies, predicting tumor grade, determining the presence of particular molecular markers, consistency, therapy response, and prognosis, can considerably influence decision-making in medicine in the near future. Even though the main focus of radiomic analyses has been on glial CNS tumors, studies on otherdoi:10.3390/cancers14030836 pmid:35159103 pmcid:PMC8834271 fatcat:dlmy3vrajbegvfelkncu2z2oam
more »... ranial tumors have shown encouraging results. Therefore, as the main focus of this review, we performed an analysis of publications on PubMed and Web of Science databases, focusing on radiomics in CNS metastases, lymphoma, meningioma, medulloblastoma, and pituitary tumors.
AbstractCerebral hypoperfusion is a key factor for determining the outcome after subarachnoid hemorrhage (SAH). A subset of SAH patients develop neurogenic stress cardiomyopathy (NSC), but it is unclear to what extent cerebral hypoperfusion is influenced by cardiac dysfunction after SAH. The aims of this study were to examine the association between cardiac function and cerebral perfusion in a murine model of SAH and to identify electrocardiographic and echocardiographic signs indicative ofdoi:10.1038/s41598-021-82583-9 pmid:33558609 pmcid:PMC7870815 fatcat:gxrijtiarrgbrn4iar2ghud4yi
more »... We quantified cortical perfusion by laser SPECKLE contrast imaging, and myocardial function by serial high-frequency ultrasound imaging, for up to 7 days after experimental SAH induction in mice by endovascular filament perforation. Cortical perfusion decreased significantly whereas cardiac output and left ventricular ejection fraction increased significantly shortly post-SAH. Transient pathological ECG and echocardiographic abnormalities, indicating NSC (right bundle branch block, reduced left ventricular contractility), were observed up to 3 h post-SAH in a subset of model animals. Cerebral perfusion improved over time after SAH and correlated significantly with left ventricular end-diastolic volume at 3, 24, and 72 h. The murine SAH model is appropriate to experimentally investigate NSC. We conclude that in addition to cerebrovascular dysfunction, cardiac dysfunction may significantly influence cerebral perfusion, with LVEDV presenting a potential parameter for risk stratification.
Excessive or incorrect loading of lumbar spinal structures is commonly assumed as one of the factors to accelerate degenerative processes, which may lead to lower back pain. Accordingly, the mechanics of the spine under medical conditions, such as scoliosis or spondylolisthesis, is well-investigated. Treatments via both conventional therapy and surgical methods alike aim at restoring a "healthy" (or at least pain-free) load distribution. Yet, surprisingly little is known about the inter-subjectdoi:10.3389/fbioe.2021.661258 pmid:34178959 pmcid:PMC8222614 fatcat:t5g6s72canc4hael6mygow4cd4
more »... variability of load bearings within a "healthy" lumbar spine. Hence, we utilized computer tomography data from 28 trauma-room patients, whose lumbar spines showed no visible sign of degeneration, to construct simplified multi-body simulation models. The subject-specific geometries, measured by the corresponding lumbar lordosis (LL) between the endplates of vertebra L1 and the sacrum, served as ceteris paribus condition in a standardized forward dynamic compression procedure. Further, the influence of stimulating muscles from the M. multifidus group was assessed. For the range of available LL from 28 to 66°, changes in compressive and shear forces, bending moments, as well as facet joint forces between adjacent vertebrae were calculated. While compressive forces tended to decrease with increasing LL, facet forces were tendentiously increasing. Shear forces decreased between more cranial vertebrae and increased between more caudal ones, while bending moments remained constant. Our results suggest that there exist significant, LL-dependent variations in the loading of "healthy" spinal structures, which should be considered when striving for individually appropriate therapeutic measures.
Cerebral hypoperfusion in the first hours after subarachnoid haemorrhage (SAH) is a major determinant of poor neurological outcome. However, the underlying pathophysiology is only partly understood. Here we induced neutropenia in C57BL/6N mice by anti-Ly6G antibody injection, induced SAH by endovascular filament perforation, and analysed cerebral cortical perfusion with laser SPECKLE contrast imaging to investigate the role of neutrophils in mediating cerebral hypoperfusion during the first 24doi:10.1038/s41598-019-44906-9 pmid:31186479 pmcid:PMC6560094 fatcat:p7lwisfgfbaw5pmelhxqcf7roy
more »... post-SAH. SAH induction significantly increased the intracranial pressure (ICP), and significantly reduced the cerebral perfusion pressure (CPP). At 3 h after SAH, ICP had returned to baseline and CPP was similar between SAH and sham mice. However, in SAH mice with normal neutrophil counts cortical hypoperfusion persisted. Conversely, despite similar CPP, cortical perfusion was significantly higher at 3 h after SAH in mice with neutropenia. The levels of 8-iso-prostaglandin-F2α in the subarachnoid haematoma increased significantly at 3 h after SAH in animals with normal neutrophil counts indicating oxidative stress, which was not the case in neutropenic SAH animals. These results suggest that neutrophils are important mediators of cortical hypoperfusion and oxidative stress early after SAH. Targeting neutrophil function and neutrophil-induced oxidative stress could be a promising new approach to mitigate cerebral hypoperfusion early after SAH.
OPEN ACCESS Citation: Neulen A, Pantel T, Kosterhon M, Kirschner S, Brockmann MA, Kantelhardt SR, et al. (2017) A segmentation-based volumetric approach to localize and quantify cerebral vasospasm based ...doi:10.1371/journal.pone.0172010 pmid:28199398 pmcid:PMC5310853 fatcat:mzo4elynv5d63o3yaeo6qtccq4
Lumbar spine biomechanics during the forward-bending of the upper body (flexion) are well investigated by both in vivo and in vitro experiments. In both cases, the experimentally observed relative motion of vertebral bodies can be used to calculate the instantaneous center of rotation (ICR). The timely evolution of the ICR, the centrode, is widely utilized for validating computer models and is thought to serve as a criterion for distinguishing healthy and degenerative motion patterns. While indoi:10.1007/s10237-020-01382-9 pmid:32939615 fatcat:tx3uk6flnngxlpoyabry57wyl4
more »... ivo motion can be induced by physiological active structures (muscles), in vitro spinal segments have to be driven by external torque-applying equipment such as spine testers. It is implicitly assumed that muscle-driven and torque-driven centrodes are similar. Here, however, we show that centrodes qualitatively depend on the impetus. Distinction is achieved by introducing confidence regions (ellipses) that comprise centrodes of seven individual multi-body simulation models, performing flexion with and without preload. Muscle-driven centrodes were generally directed superior-anterior and tail-shaped, while torque-driven centrodes were located in a comparably narrow region close to the center of mass of the caudal vertebrae. We thus argue that centrodes resulting from different experimental conditions ought to be compared with caution. Finally, the applicability of our method regarding the analysis of clinical syndromes and the assessment of surgical methods is discussed.
Clinical studies on subarachnoid hemorrhage (SAH) have shown discrepancies between large vessel vasospasm, cerebral perfusion, and clinical outcome. We set out to analyze the contribution of large vessel vasospasm to impaired cerebral perfusion and neurological impairment in a murine model of SAH. SAH was induced in C57BL/6 mice by endovascular filament perforation. Vasospasm was analyzed with microcomputed tomography, cortical perfusion by laser SPECKLE contrast imaging, and functionaldoi:10.1007/s12975-018-0647-6 pmid:30003500 fatcat:psxpljtzcveunbyqfumvxw665u
more »... nt with a quantitative neuroscore. SAH animals developed large vessel vasospasm, as shown by significantly lower vessel volumes of a 2.5-mm segment of the left middle cerebral artery (MCA) (SAH 5.6 ± 0.6 nL, sham 8.3 ± 0.5 nL, p < 0.01). Induction of SAH significantly reduced cerebral perfusion of the corresponding left MCA territory compared to values before SAH, which only recovered partly (SAH vs. sham, 15 min 35.7 ± 3.1 vs. 101.4 ± 10.2%, p < 0.01; 3 h, 85.0 ± 8.6 vs. 121.9 ± 13.4, p < 0.05; 24 h, 75.3 ± 4.6 vs. 110.6 ± 11.4%, p < 0.01; 72 h, 81.8 ± 4.8 vs. 108.5 ± 14.5%, n.s.). MCA vessel volume did not correlate significantly with MCA perfusion after 72 h (r = 0.34, p = 0.25). Perfusion correlated moderately with neuroscore (24 h: r = − 0.58, p < 0.05; 72 h: r = − 0.44, p = 0.14). There was no significant correlation between vessel volume and neuroscore after 72 h (r = − 0.21, p = 0.50). In the murine SAH model, cerebral hypoperfusion occurs independently of large vessel vasospasm. Neurological outcome is associated with cortical hypoperfusion rather than large vessel vasospasm.
Copyright © 2020 Neulen, Kunzelmann, Kosterhon, Pantel, Stein, Berres, Ringel, Brockmann, Brockmann and Kantelhardt. ...doi:10.3389/fneur.2020.00013 pmid:32082241 pmcid:PMC7002561 fatcat:xxis5tsjffevhb4g5im2eqaefe
Subarachnoid hemorrhage (SAH) is a subtype of hemorrhagic stroke. Cerebral vasospasm that occurs in the aftermath of the bleeding is an important factor determining patient outcome and is therefore frequently taken as a study endpoint. However, in small animal studies on SAH, quantification of cerebral vasospasm is a major challenge. Here, an ex vivo method is presented that allows quantification of volumes of entire vessel segments, which can be used as an objective measure to quantifydoi:10.3791/57997 pmid:30102288 pmcid:PMC6126573 fatcat:y25e4x3oe5f75mh64jxwijfrsa
more »... vasospasm. In a first step, endovascular casting of the cerebral vasculature is performed using a radiopaque casting agent. Then, cross-sectional imaging data are acquired by micro computed tomography. The final step involves 3-dimensional reconstruction of the virtual vascular tree, followed by an algorithm to calculate center lines and volumes of the selected vessel segments. The method resulted in a highly accurate virtual reconstruction of the cerebrovascular tree shown by a diameter-based comparison of anatomical samples with their virtual reconstructions. Compared with vessel diameters alone, the vessel volumes highlight the differences between vasospastic and non-vasospastic vessels shown in a series of SAH and sham-operated mice.
Frontiers in Surgery
Kosterhon et al. (47) reported the use of AR in a patient with congenital hemivertebra of the thoracolumbar spine, and the system was found useful for the surgeon during the resection of a complex-shaped ... Abe et al. (45) Spine surgery VIPAR The AR-based system offered a remarkable help to surgeons to find the ideal needle trajectory and insertion point when performing percutaneous vertebroplasty Kosterhon ...doi:10.3389/fsurg.2019.00038 pmid:31316995 pmcid:PMC6610425 fatcat:teqq622shrg2dblvw3cidzbane
Quantitative assessment and localization of the hollowing of the temple after craniectomy and cranioplasty -The frontozygomatic shadow ID: 605 Michael Kosterhon* 1 , Eva Ruegg 2 , Malte Ottenhausen 1 , ...doi:10.1515/iss-2022-2005 fatcat:rcrdth7nufgxpo433ogjq7howe
., 15346, 1387, 1434 Kosterhon, K., 1364 Krantz, K. W., 1364 Krebs, R. W., 1364, 1387 Krejei, J. ©., 1887 Krekeler, H., 1451 Kretschmer, R., 1393 Kroger, M., 1387 Kruber, O., 1454 Kuhn, G. ... J., Mercier, Mering, J., Metallges, L379, L405, Michael, she Mikeska, Miller, ©. Miller, (. 5 Miller, Miller, Miller, i Miller, I. A., Miller, R Miller, 8. Miller, W Milliken, Mills, G. ...
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