Fig 1 - uploaded by Ramin Naraghi
Content may be subject to copyright.
Axial source images of 3D-CISS sequences at the level of the trigeminal nerve root (A and B) and 3D-TOF MRAs at the level of the cavernous sinus (C and D) at 1.5T (A and C) and 3T (B and D) in the same patient. Note the ramification of the nerve root into its branches at some distance from the REZ. The branches are much better outlined at 3T than at 1.5T in the 3D-CISS sequence (A and B). The vessels and the boundary between the cavernous sinus and ICA can be distinguished more accurately at 3T than at 1.5T in the 3D-TOF MRA (C and D). Note the banding artifacts over the globes in the 3D-CISS at 3T (B). Ghosting artifacts are seen anterior to the CSF in the 3D-CISS at both field strengths (A and B).
Source publication
High-resolution MR imaging is useful for diagnosis and preoperative planning in patients with NVC. Because high-field MR imaging promises higher SNR and resolution, the aim of this study was to determine the value of high-resolution 3D-CISS and 3D-TOF MRA at 3T compared with 1.5T in patients with NVC.
Forty-seven patients with NVC, trigeminal neura...
Contexts in source publication
Context 1
... the CISS sequence) and the conspicuity of the boundary between the cavernous sinus and ICA (P .001 for both sequences) (Fig 1C, -D) were signifi- cantly better delineated at 3T than at 1.5T, due to the sharper contrast and fewer artifacts at 3T. ...
Context 2
... mainly CSF. Similarly, the single branches of CN V could be significantly better differentiated from the surrounding CSF at 3T (Fig 1A, -B). ...
Context 3
... drawback of 3D-CISS are banding artifacts, which are more pronounced at high-field MR imaging due to increased susceptibility. Dark bands were seen in some patients at 3T over the ocular globe (Fig 1B), which were easily detectable and did not interfere with diagnostic quality. No banding artifacts were seen in the basal cisterns. ...
Context 4
... artifacts at 3T could be eliminated by lowering the flip angle (Table 1). Ghosting artifacts resulting from CSF pulsation were seen at both 1.5T and 3T anterior to the CSF in the phase-encoding direction (Fig 1A, -B). Although these artifacts were some- times slightly wider at 3T, they could be much better separated from the underlying brain tissue, and this, together with the higher SNR and CNR, still resulted in better image quality at 3T. ...
Similar publications
Syncopal convulsions and epileptic seizures are clinically hard to distinguish and differ in terms of treatment approaches. It is important to consider the cardiac arrhythmias that impair cerebral perfusion in the differential diagnosis of antiepileptic treatment-resistant convulsions. Here we offer a 72 year old male patient glossopharengial neura...
Aim:
There is a feared complication for cerebrospinal fluid (CSF) leakage after microvascular decompression (MVD). In this study we present our experience of fleece-bound tissue sealing in MVD with our aim to minimize the rate of postoperative CSF leakage.
Material and methods:
We treated 50 patients (female/male: 26/24) with neurovascular compr...
In the context of painful cranial neuropathies, a very rare cause is represented by the irritation of the glossopharyngeal nerve due to various aetiologic factors. Here, we present a case of neuralgia of the ninth right cranial nerve due to a compression of its nerve root upon the kinking of the homolateral vertebral artery, resulting in a disablin...
Citations
... 2D visualization based on slice images is a common approach to assess NVC syndromes. Image data obtained on a MR scanner with 3.0 Tesla (T) field strength has been reported to improve the spatial resolution and hence 2D visualizations compared to image data obtained with 1.5 T field strength [9]. Furthermore, the question arises whether a general recommendation can be made to use only 3.0 T for the evaluation of NVC. ...
... Image data All patients prospectively obtained image data with MRI at 1.5 T and 3.0 T (Magnetom Sonata and Magnetom Tim Trio, Siemens, Erlangen, Germany) using an institutional protocol to obtain high-resolution 3D-CISS and 3D-TOF data. On both systems, the two sequences were adjusted to isotropic voxel size (0.4 mm) providing equally high resolution in axial, coronal and sagittal orientation (details in [9]). The acquisition of two MRI studies with different field strengths per patient was part of a research initiative. ...
... With regard to the subsequent registration, the segmented vessels in the TOF data were labeled in the same way as the extracted CSF area in the CISS data. Since the quality of the CISS and TOF data can be impaired to varying degrees due to various imaging artifacts, this also has a direct impact on subsequent steps of image processing [9,12]. In order to improve the segmentation results in these cases, they were additionally processed by manual editing based on expert knowledge in a further step. ...
Background
Neurovascular relationships in the posterior fossa are more frequently investigated due to the increasing availability of 3.0 Tesla MRI. For an assessment with 3D visualization, no systematic analyzes are available so far and the question arises as to whether 3.0 Tesla MRI should be given preference over 1.5 Tesla MRI.
Methods
In a prospective study, a series of 25 patients each underwent MRI investigations with 3D-CISS and 3D-TOF at 1.5 and 3.0 Tesla. For both field strengths separately, blood vessel information from the TOF data was fused into the CISS data after segmentation and registration. Four visualizations were created for each field strength, with and without optimization before and after fusion, which were evaluated with a rating system and verified with the intraoperative situation.
Results
When only CISS data was used, nerves and vessels were better visualized at 1.5 Tesla. After fusion, flow and pulsation artifacts were reduced in both cases, missing vessel sections were supplemented at 3.0 Tesla and 3D visualization at 1.5 and 3.0 Tesla led to anatomically comparable results. By subsequent manual correction, the remaining artifacts were further eliminated, with the 3D visualization being significantly better at 3.0 Tesla, since the higher field strength led to sharper contours of small vessel and nerve structures.
Conclusion
3D visualizations at 1.5 Tesla are sufficiently detailed for planning microvascular decompression and can be used without restriction. Fusion further improves the quality of 3D visualization at 3.0 Tesla and enables an even more accurate delineation of cranial nerves and vessels.
... These sequences best delineate the morphology of the cisternal trigeminal nerve. 9,10 Additionally, the offending arteries or veins are seen as serpiginous flow voids that contact or compress the trigeminal nerve. Compressed nerves can be displaced, deformed, or appear atrophic. ...
... Moreover, compression of the trigeminal nerve at its entry into the brainstem has a nearly 100% sensitivity and positive predictive value. 6,[9][10][11] Although heavily T2weighted sequences yield excellent anatomic detail, there is often poor contrast between the nerves and the vessels. There is utility in contrast-enhanced 3D-CISS imaging to improve the characterization of high-grade neurovascular compression, localize the side of patient symptoms and predict the outcome following microvascular decompression (MVD). ...
There are many lesions that cause compression of nerves and vessels in the head and neck, and they can often be overlooked in the absence of adequate history or if not suspected by the radiologist. Many of these lesions require a high index of suspicion and optimal positioning for imaging. While a multimodality approach is critical in the evaluation of compressive lesions, an MRI utilizing high-resolution (heavily weighted) T2-weighted sequence is extremely useful as a starting point. In this review, we aim to discuss the radiological features of the common and uncommon compressive lesions of the head and neck which are broadly categorized into vascular, osseous, and miscellaneous etiologies.
... In addition, 3-T MRA units obtain better separation between veins and small arteries than 1.5-T MRI units do. 68 Contrast-Enhanced Imaging. Unlike TOF and PC MRA, CE MRA does not rely on FRE or phase differences to create contrast. ...
Chapter 411: Neurovascular Imaging, Youmans & Winn Neurological Surgery, 8e
... In most studies in the literature, the morphometry of the facial and cochlear nerves was performed using high-resolution 3T MR to analyze auditory neuropathy spectrum disorders, like sensorineural hearing loss and facial palsy. Comparing a 3D CISS sequence performed at 3T and at 1.5 T MRI in the study of IAC structures, Garcia et al. demonstrated the superiority of 3T MR imaging for SNR and CNR, better delineation and anatomical details of cranial nerves, nerve branches and small vessels, with lower artifacts [37]. ...
Three-dimensional constructive interference in steady state (3D CISS) is a steady-state gradient-echo sequence in magnetic resonance imaging (MRI) that has been used in an increasing number of applications in the study of brain disease in recent years. Owing to the very high spatial resolution, the strong hyperintensity of the cerebrospinal fluid signal and the high contrast-to-noise ratio, 3D CISS can be employed in a wide range of scenarios, ranging from the traditional study of cranial nerves, the ventricular system, the subarachnoid cisterns and related pathology to more recently discussed applications, such as the fundamental role it can assume in the setting of acute ischemic stroke, vascular malformations, infections and several brain tumors. In this review, after briefly summarizing its fundamental physical principles, we examine in detail the various applications of 3D CISS in brain imaging, providing numerous representative cases, so as to help radiologists improve its use in imaging protocols in daily clinical practice.
... Established sequences for the assessment of NVC are high-spatial-resolution strong 3D gradient echo T2-weighted imaging, i.e., Constructive Interference in Steady State (CISS), and MR-angiography, i.e., Time-of-Flight (TOF) [14,19,22]. In addition to that, the higher signal of 3.0 Tesla can improve the spatial resolution for the assessment of NVC [7]. ...
... In addition, vessels at the boundary of the CSF suffer from contour fusion with neighboring structures, thereby preventing their precise delineation [16]. On the other hand, in-plane and small vessels are not consistently reproduced in TOF data due to known restrictions [7]. To solve these problems, the principles of data fusion based on the source data are applied for the first time and the corresponding results of the 3D visualization are presented. ...
... Both sequences were adjusted to isotropic voxel size (0.4 mm) ensuring equally high resolution in axial, coronal, and sagittal slice images. Details of the sequence parameters were previously published [7,16]. ...
Background
Reliable 3D visualization of neurovascular relationships in the posterior fossa at the surface of the brainstem is still critical due to artifacts of imaging. To assess neurovascular compression syndromes more reliably, a new approach of 3D visualization based on registration and fusion of high-resolution MR data is presented.
Methods
A total of 80 patients received MRI data with 3D-CISS and 3D-TOF at 3.0 Tesla. After registration and subsequent segmentation, the vascular information of the TOF data was fused into the CISS data. Two 3D visualizations were created for each patient, one before and one after fusion, which were verified with the intraoperative situation during microvascular decompression (MVD). The reproduction quality of vessels was evaluated with a rating system.
Results
In all cases, the presented approach compensated for typical limitations in the 3D visualization of neurovascular compression such as the partial or complete suppression of larger vessels, suppression of smaller vessels at the CSF margin, and artifacts from heart pulsation. In more than 95% of the cases of hemifacial spasm and glossopharyngeal neuralgia, accurate assessment of the compression was only possible after registration and fusion. In more than 50% of the cases with trigeminal neuralgia, the presented approach was crucial to finding the actually offending vessel.
Conclusions
3D visualization of fused image data allows for a more complete representation of the vessel-nerve situation. The results from this approach are reproducible and the assessment of neurovascular compression is safer. It is a powerful tool for planning MVD.
... Established sequences for preoperative assessment of NVC are high spatial resolution strong 3D-gradient echo T2-weighted imaging, i.e. constructive interference in steady state (CISS) and MRangiography, i.e. time-of-flight (TOF) [11][12][13][14][15]. In addition, the higher signal of 3 T can improve the spatial resolution for the assessment of NVC [16]. ...
... High-resolution CISS and TOF sequences are necessary tools for the assessment of neurovascular relationships in NVC. There is further consensus that patients with NVC may benefit from higher resolution and greater sensitivity of 3.0 T MRI [16]. The quality of the source images is of utmost importance [28]. ...
PurposeControversy exists on the association of arterial hypertension (HTN) and neurovascular compression (NVC) at the ventrolateral medulla (VLM). No standardized and reproducible technique has been introduced yet for detection of NVC in HTN. This study aimed to generate, analyze and compare different results of exact reproducible anatomical 3D-representations of the VLM in patients with HTN, based on magnetic resonance imaging (MRI).MethodsA 3T scanner provided MRI (T2-constructive interference in steady state (CISS) high resolution imaging and three-dimensional Time-of-flight (3D-TOF) angiography) from the posterior fossa of 44 patients with clinical treatment-resistant HTN. Image processing consists of segmentation of the CISS data, registration and fusion of the CISS and TOF data and visualization. For each patient two 3D-visualizations (before and after fusion) were obtained. The reproduction quality of the vessels, flow-related signal variability and pulsation artifacts were analyzed and compared, using a ranking score.ResultsIntegrating vascular information from TOF into CISS data reduced artifacts in 3D-visualizations of exclusively processed CISS data. The quality of 3D-visualization of the vessels near the brain stem was significantly improved (p = 0.004). The results were reproducible and reliable. The quality of the 3D-presentations of neurovascular relationships at the VLM improved significantly (p < 0.001).Conclusion
The 3D-visualization of fused image data provides an excellent overview of the relationship between cranial nerves and vessels at the VLM and simplifies the detection of NVC in HTN. It provides a powerful tool for future clinical and scientific research. Although microvascular decompression (MVD) in treatment resistant HTN is not a standard procedure, it can be discussed in selected patients with intractable severe HTN.
... However, there is no appreciable contrast between the nerve and the vessels surrounding it, making it difficult to estimate the severity of neurovascular compression [11]. This is a significant disadvantage when optimizing the selection of patients and undertaking pre-operative planning, as the severity of neurovascular compression is strongly correlated with longterm symptomatic relief after MVD [9][10][11][12][13][14][15]. TOF-MRA, typically combined with B-FFE/SSFP sequences, can identify arterial compression but its elucidation of small arteries and veins is limited [8,16,17]. ...
... This facilitated higher accuracy and greater consistency in surgical exploration of the degree of compression. Since patients with high-grade compression should gain additional benefit from MVD [9][10][11][12][13][14][15], MR subtraction was found to perform better in prognosis after MVD and perform better in optimizing patient selection before MVD. The type of compressing vessel was identified well by both methods: accuracy was 90.12% for MR subtraction and 91.25% for the conventional method. ...
Purpose
To investigate the ability of magnetic resonance (MR) subtraction to evaluate neurovascular conflict (NVC) and to compare it with conventional MR protocols.
Methods
This prospective study included 82 patients with trigeminal neuralgia who underwent microvascular decompression for NVC. All patients had a pre-operative examination using 3T MRI. The MRI protocols used comprised 3D balanced (B)-fast field echo (FFE), 3D steady-state magnetic resonance angiography (MRA), and 3D T1-FFE sequences. MR subtraction images were obtained by subtracting native images from B-FFE and steady-state MRA. NVC evaluation was performed using subtraction images (MR subtraction) and combination images (conventional MR protocols using B-FFE and T1-FFE in combination). Clinical assessment of the degree of compression, the type of compressing vessel, and the location of conflict were undertaken by two independent observers. The two methods were then compared using surgical criteria.
Results
MR subtraction exhibited greater accuracy than the conventional method in terms of the estimated severity of conflict (87.80% vs. 57.32%, p < 0.05), and demonstrated better consistency with surgical findings (k = 0.794 vs. k = 0.365, p < 0.05). For the type of compressing vessel and the location of conflict, both methods were highly accurate and agreed to a similar extent with surgical findings (p = 0.987, compressing vessel; p = 0.665, location of conflict).
Conclusion
MR subtraction proved reliable in NVC pre-operative evaluation, with increased accuracy when estimating severity. This result strongly supports the wider use of MR subtraction as the preferred choice in clinical application.
... Highresolution 3D-CISS MR imaging has been reported useful in diagnosis and preoperative planning in patients with neurovascular conflict. 21 Vestibulocochlear symptoms such as vertigo, nystagmus, sensorineural hearing loss, and tinnitus can be precipitated from a neurovascular compression of the vestibulocochlear nerve by VBD. 9 In this study, the patient presented with symptoms of simultaneous abducens and vestibulocochlear nerves, which are presumed to be secondary to the VBD on the basis of the following remarks: (a) the patient presented with abducent and vestibulocochlear symptoms of intermittent left-sided diplopia, paroxysmal vertigo and left-sided typewriter tinnitus; (b) high-resolution images of 3D-CISS sequences has clearly showed that a dolichoectatic BA markedly conflicted with both abducens and vestibulocochlear nerve roots; (c) other pathologies such as vestibular disorder were absent. In patients with dolichoectasia, BA diameter >4.3 mm may be a predictor of fatal stroke, highlighting the importance of this disease and necessitate proper and prompt treatment. ...
Vertebrobasilar dolichoectasia (VBD) can lead to cranial nerve symptoms. However, multiple cranial nerve symptoms associated with VBD in one case remain extremely rare. We here present the case of a 33-year-old male with VBD diagnosed by multimodality imaging, who developed simultaneous abducens and vestibulocochlear nerve symptoms and subsequently improved after blood pressure control treatment. To our knowledge, this is the first report of such a vascular disorder resulting in simultaneous symptoms of the abducens and vestibulocochlear nerves. This study highlights that such a vascular anomaly should be considered when cranial nerve symptom is encountered, especially when multiple cranial nerves involved. Meanwhile, radiological evalurrrrrrrrrrrrrrrrrrration of such neurovascular conflict using three-dimensional constructive interference in steady-state imaging is recommended.
... An accurate delineation of the responsible vessel may decrease the rate of possible operative complications such as nerve paresis. A detailed preoperative anatomic evaluation using MR imaging is now widely used for precise assessment of neurovascular relationships [11]. ...
Background
Neurovascular compression syndromes including trigeminal neuralgia (TN) and hemifacial spasm (HFS) are caused by neurovascular conflicts at the root entry zone of the corresponding cranial nerves in the posterior fossa. Microvascular decompression (MVD) is the best choice for the treatment of TN and HFS. An accurate delineation of the responsible vessel could decrease the rate of possible operative complications such as nerve paresis.
Methods
In this study, three-dimensional fast imaging employing steady-state acquisition (3D-FIESTA) and three-dimensional time-of-flight magnetic resonance angiography (3D-TOF MRA) were performed on 113 patients with TN or HFS. The imaging data were compared to the intraoperative findings and the accuracy of the data was calculated among the different responsible blood vessels and disease types. The accuracy of the data among different genders, disease durations, disease sides, and disease types was also calculated to identify the target patients for the preoperative diagnostic approach with 3D-FIESTA combined with 3D-TOF MRA.
Results
The accuracy of detection with the imaging was above 75% in cases with single-vessel compression. Among these, the accuracy of the preoperative imaging result was the highest when the lesions were in the superior cerebellar artery (SCA; 91.1%). In cases of multiple-vessel compression, however, the coincidence between the preoperative and intraoperative results was only 30.0%. In most of the cases of TN, the responsible blood vessels were in the SCA, and the accuracy in the SCA reached 94.9%. In HFS patients, the responsible blood vessels were in the anterior inferior cerebellar artery (AICA) and posterior inferior cerebellar artery (PICA), and the accuracy was 86.8% and 90.0%, respectively. The differences in the accuracy of the data among different genders, disease durations, disease sides, and disease types were not statistically significant.
Conclusion
This study verified the clinical instructional value of 3D-FIESTA combined with 3D-TOF MRA in MVD, and showed that this preoperative examination is reliable for all genders, disease durations, disease sides, and disease types.
... Entsprechend der mathematischen Formel für den Signal-Rausch-Abstand SNR=S/N (engl.: signal-to-noise-ratio=SNR) ergibt sich aus der Erhöhung der Feldstärke ein höherer Wert für SNR 61 und damit eine verbesserte Bildqualität.Insgesamt zielen die 3,0 T MRT-Geräte auf eine detaillierte Darstellung der strukturellen und funktionellen Anatomie. Die bisherige Erfahrung hat gezeigt16,50,51 , dass 3,0 T MRT-Messungen gerade bei NVK-Syndromen die Möglichkeit einer größeren diagnostischen Sicherheit bietet.3.3 Medizinische Visualisierung und BildverarbeitungDie Medizinische Bildverarbeitung zielt darauf ab, die mit den Verfahren der medizinischen Bildgebung (CT, MRT) erstellten Bilddaten zu analysieren, sie miteinander zu verbinden und anschaulich darzustellen, um die Diagnostik und die Therapie zu unterstützen. ...
1 Zusammenfassung 1.1 Hintergrund und Ziele Neurovaskuläre Kompressionssyndrome sind pathologische hyperaktive Funktionsstörungen von Nerven, die durch Kompression der Hirnnerven durch Gefäße verursacht werden. Als Kompression bezeichnet man den pathologischen Kontakt von Nerv und Gefäß entlang des Nervenstranges, der sich an verschiedenen Stellen bilden kann. Entscheidend sind nicht nur die Kompression an sich, sondern auch die dauerhaften, pulsatilen Signale des Gefäßes an bestimmten sensiblen Stellen der Nervenstrecke. Bei diesen empfindlichen Regionen handelt es sich um Stellen, die sich meistens hirnstammnah befinden und eine geringe Myelinumhüllung aufweisen. Diese pathologischen Kontakte findet man an der Nervenwurzeleintrittszone, Nervenwurzelaustrittszone und an anderen Stellen. Beteiligt sind meistens die A. vertebralis, die A. basilaris, die A. anterior inferior cerebri, die A. posterior inferior cerebri, die A. posterior cerebelli, und die A. superior cerebelli, aber auch in einigen Fällen Venen, die entlang oder sogar durch die Hirnnerven verlaufen35. Als Folge dieser Kompression entstehen venöse oder arterielle Durchblutungsstörungen oder neurologische Reizerscheinungen. Zu den neurovaskulären Kompressionssyndromen gehören Krankheitsbilder wie die Trigeminusneuralgie, die Glossopharyngeusneuralgie und der Spasmus Hemifazialis. Diese Arbeit beschäftigt sich mit den Unterschieden zwischen 3D-Visualisierungen von 1,5 und 3,0 Tesla Daten für die Darstellung neurovaskulärer Kompressionssyndrome. Hierfür wurden die erstellten Visualisierungen sowohl vor Bearbeitung mit Methoden der Bildverarbeitung als auch danach miteinander verglichen. Die 3D-Visualisierungen wurden bezüglich der Darstellung der neurovaskulären Kompression und der Bildqualität ausgewertet. Es ist die erste Arbeit, die dreidimensionale Visualisierungen von 1,5 und 3,0 Tesla Daten bei Patienten mit neurovaskulären Kompressionssyndromen vergleicht, sowie die Bildverarbeitung und die Bildqualität abhängig vom Auftreten bestimmter Artefakten evaluiert. 1.2 Methoden In dieser Arbeit wurden insgesamt 25 Patienten eingeschlossen, die in der Neurochirurgischen Klinik des Universitätsklinikum Erlangen untersucht wurden (n=19 Trigeminusneuralgie, n=1 Glossopharyngeusneuralgie und n= 5 Spasmus Hemifazialis). Bei allen Patienten erfolgten Magnetresonanztomographie-Messungen mit 1,5 und 3,0 Tesla, wobei die Aufnahmeprotokolle TOF und die stark T2 gewichtete CISS-Sequenz angewendet wurden. Die Bilddaten wurden mittels Methoden der Bildverarbeitung, wie Segmentierung, Registrierung und Fusion bearbeitet, um dreidimensionale Visualisierungen zu erstellen und die pathologischen Kontakte und anatomischen Auffälligkeiten darzustellen. Durch Segmentierung wurden die anatomischen Strukturen voneinander abgegrenzt. Mit Registrierung wurden die Bilddaten so aufeinander abgebildet, so dass sie im nächsten Schritt fusioniert werden konnten. Am Ende erfolgte eine Optimierung, d.h. eine manuelle Verbesserung der Segmentierung. Mit Volumenvisualisierung wurden die dreidimensionalen Darstellungen erstellt, so dass die Ergebnisse von der 1,5 und 3,0 Tesla verglichen werden konnten. Mittels eines Punktevergabesystems wurde die Auswertung der Volumendaten bei 1,5 und 3,0 Tesla durchgeführt. Die erstellten 3D-Visualisierungen wurden sowohl vor, als auch Anwendung der Bildverarbeitung analysiert und verglichen. 1.3 Ergebnisse und Beobachtungen Es hat sich gezeigt, dass sich durch die Fusion der Daten die Beeinträchtigung der 3D-Darstellung durch Flussartefakte vor allem bei den großen Gefäßen signifikant verbessern lässt. Die Optimierung brachte sowohl bei den fusionierten als auch bei den nicht fusionierten Visualisierungen eine vergleichsweise geringfügigere Verbesserung in der Bewertung, eliminierte jedoch die Pulsationsartefakte, was die Bildqualität positiv beeinflusst. Der Vergleich der 3D-Darstellungen ergab, dass mit den 1,5 Tesla Daten bessere Ergebnisse erzielt werden können, wenn nur die CISS-Daten verwendet werden. Wurden jedoch die CISS- und TOF-Daten im Rahmen der Bildverarbeitung fusioniert, kam es bei den 3,0 Tesla Daten zu verbesserten Ergebnissen in der Bewertung, auf Grund der Unterdrückung der Flussartefakte bei den großen Gefäßen. Wurde zusätzlich die Segmentierung der fusionierten Bilddaten manuell optimiert, konnten die verbliebenen Einschränkungen durch die wenigen Pulsationsartefakte vollständig eliminiert werden. Der Vergleich der 3D-Visualisierung von fusionierten und optimierten 1,5 und 3,0 Tesla Daten führte bei den 3,0 Tesla Daten zu den besten Ergebnissen in der Bewertung. Auf Grund einer klareren Wiedergabe von Gefäßen und Nerven war der erforderliche zeitliche Aufwand für die Bildverarbeitung und 3D-Visualisierung bei den 3,0 Tesla Daten geringer als bei den 1,5 Tesla Daten. 1.4 Praktische Schlussfolgerungen Durch den Prozess der Bildverarbeitung und 3D-Visualisierung können hirnstammnahe Beziehungen der Anatomie sauber und detailliert reproduziert werden. Abhängig vom Krankheitsbild und den betroffenen Gefäßen kann die Magnetfeldstärke bestimmt werden, die optimal geeignet ist. Die fusionierten, optimierten 3,0 Tesla 3D-Visualisierungen sind ein ideales Werkzeug, um die anatomischen Zusammenhänge bei neurovaskulären Kompressionssyndromen noch genauer abzubilden und zu verstehen. Die Kompressionssyndrome sind für die Patienten ein sehr belastendes Krankheitsbild. Eine erfolgreiche und komplikationsarme Therapiemöglichkeit ist die operative Behandlung nach Jannetta. Die Erkenntnisse dieser Arbeit sind eine hilfreiche Unterstützung, NVC sicher zu diagnostizieren und die prä- und intraoperativen Planung zu optimieren.
