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ABSTRACT: Percutaneous renal biopsy (PRB) of kidney transplants might be prevented by an elevated risk of bleeding or limited access to the allograft. In the following, we describe our initial experience with 71 transvenous renal transplant biopsies in 53 consecutive patients with unexplained reduced graft function who were considered unsuitable candidates for PRB (4.2% of all renal transplant biopsies at our institution). Biopsies were performed via the ipsilateral femoral vein with a renal biopsy set designed for transjugular renal biopsy (TJRB) of native kidneys. Positioning of the biopsy system within the transplant vein was achievable in 58 of 71 (81.7%) procedures. The specimen contained a median of 10 glomeruli (range 0-38). Tissue was considered as adequate for diagnosis in 56 of 57 (98.2%) biopsies. With respect to BANFF 50.9% of the specimen were adequate (>10 glomeruli), 47.4% marginally adequate (1-9 glomeruli) and 1.8% inadequate (no glomeruli). After implementation of real-time assessment all specimen contained glomeruli. One of the fifty-eight (1.8%) procedure-related major complications occurred (hydronephrosis requiring nephrostomy due to gross hematuria). Transfemoral renal transplant biopsy (TFRTB) is feasible and appears to be safe compared to PRB. It offers a useful new alternative for histological evaluation of graft dysfunction in selected patients with contraindications to PRB.
American Journal of Transplantation 03/2013; · 6.39 Impact Factor
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ABSTRACT: Wir berichten über einen 80-jährigen Patienten mit einer hochgradigen Karotisstenose links, der nach technisch erfolgreich
implantiertem Karotisstent eine transiente Monoparese des rechten Arms entwickelte. Eine intrakranielle Bildserie als Abschluss
der Intervention zeigte keine Auffälligkeiten, insbesondere war ein Gefäßverschluss nicht nachweisbar. In der direkt nach
Beginn der Symptomatik durchgeführten Schädel-CT (CCT) war eine lineare Hyperdensität im Sulcus praecentralis links mit geringer
ipsilateraler Hirnschwellung nachweisbar. Die transkranielle Dopplersonographie ergab eine postinterventionelle Blutflussbeschleunigung
in der linken A.cerebri media verglichen mit dem präoperativen Wert und eine deutlich erhöhte Hirndurchblutung, sodass die
Diagnose eines Hyperperfusionssyndroms mit subpialer Einblutung gestellt wurde. Nach konsequenter Blutdruckkontrolle und -einstellung
bildete sich das neurologische Defizit sukzessiv zurück, und in der Kontroll-CCT 15h nach Symptombeginn war die Hyperdensität
nicht mehr nachweisbar.
We report on an 80-year-old hypertensive patient with a left-sided high-grade carotid stenosis who developed transient monoparesis
of the right arm after stenting of the carotid artery. Computed tomography (CT) of the brain (cranial CT) performed immediately
after the symptomatic had begun showed a linear hyperdensity in the ipsilateral, precentral sulcus with a moderate, local
brain swelling and edema. Transcranial doppler sonography revealed an accelerated post-interventional systolic blood flow
velocity and in the ipsilateral medial cerebral artery compared to the preoperative value and an increased cerebral blood
flow, so that the diagnosis of hyperperfusion syndrome with a subpial hematoma was confirmed. After strict blood pressure
control and -reduction the neurological deficit regressed gradually and the hyperdensity had completely disappeared in control
CCT after 15h.
SchlüsselwörterZerebrales Hyperperfusionssyndrom–Karotisangioplastie–Karotisstenting–Blutung–Neurologisches Defizit
KeywordsCerebral hyperperfusion syndrome–Angioplasty–Carotid artery stenting–Hemorrhage–Neurological deficit
Der Radiologe 05/2012; 51(4):293-295. · 0.61 Impact Factor
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ABSTRACT: 4–5% aller malignen Tumoren betreffen die Kopf-Hals-Region. Mit der Computertomographie (CT) und der Kernspintomographie (MRT)
können wir die Ausdehnung und Infiltrationstiefe der Raumforderung exakt bestimmen, submuköses Wachstum nachweisen, ein präoperatives
Lymphknotenstaging durchführen und somit eine bessere präoperative Planung ermöglichen. Mit der modernen Mehrschicht-Spiral-CT
sind dünnere Schichtkollimationen und kürzere Untersuchungszeiten möglich. Aus den Volumendatensätzen lassen sich 2D- und
3D-Darstellungen zur Beurteilung der Schädelbasis (koronare und sagittale Schichten) und der Mittellinienüberschreitung von
Tumoren sowie zum Lymphknotenstaging(koronare Schichten) berechnen. Auch die Untersuchung der Funktion des Larynx und Hypopharynx
sowie die Bestimmung der Tumorperfusion sind möglich.
In der CT ist die Detektion von Tumoren, die kein Kontrastmittel aufnehmen (ca. 15%), erschwert. Die MRT bietet neben einem
hohen Gewebekontrast die Möglichkeit, Schnittbilder direkt in beliebigen Schnittebenen zu akquirieren. Im Gegensatz zur CT
spielen Metallartefakte kaum eine Rolle. Die Infiltration der Dura und des Cerebrums lassen sich mit der MRT besser als mit
der CT nachweisen. Die immer noch lange Untersuchungszeit der MRT bedingt die Gefahr von Bewegungsartefakten. Wichtig in der
Kopf-Hals-Region ist die Fettunterdrückung in T2-gewichteten Sequenzen und in T1-gewichteten Sequenzen nach Kontrastmittelgabe.
Entzündungen im Kopf-Hals-Bereich werden nur in Ausnahmefällen mit CT oder MRT abgeklärt.
Obligat wird die CT zur Planung vor funktionell-endoskopischen Operationen der Nasennebenhöhlen durchgeführt. Weitere Indikationen
für die CT und MRT bei Entzündungen sind die retrotonsilläre und parapharyngeale Diagnostik von Abszessen und ihren Komplikationen
sowie die Diagnostik einer Osteomyelitis. Da bei akuter Entzündung bei Sialolithiasis eine konventionelle Sialographie kontraindiziert
ist, kann hier die MR-Sialographie angewendet werden.
Detection of tumors that do not absorb any contrast medium (approximately 15%) is more difficult with CT. In addition to providing
a high degree of tissue contrast, MRI makes it possible to directly acquire images in any number of planes. In contrast to
CT, metallic artefacts hardly come into play. Infiltration of the dura and the cerebrum can be depicted better with MRI than
with CT. The long examination time with MRI carries the risk of movement artefacts. In the head and neck region, it is important
to suppress fat in T2-weighted sequences and in T1-weighted sequences after administration of contrast media. Inflammations
in the head and neck region are only exceptionally clarified with CT or MRI.
It is imperative that CT be performed before functional endoscopic operations of the paranasal sinuses. Further indications
for CT and MRI in cases of inflammation are the diagnosis of retrotonsillar and parapharyngeal abscesses and ensuing complications
as well as the diagnosis of osteomyelitis. Since conventional sialography is contraindicated in acute inflammation in sialolithiasis,
magnetic resonance sialography can be employed.
HNO 04/2012; 50(7):611-625. · 0.40 Impact Factor
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RöFo - Fortschritte auf dem Gebiet der R 10/2011; 183(10):906-8. · 2.76 Impact Factor
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ABSTRACT: Computed tomography is an essential modality for imaging of the temporal bone. Newest generation scanners allow the coverage of large examination volumes with a single gantry rotation. The objective of this study was to compare a 128-section SST (1 single rotation of the x-ray tube) with conventional spiral MSCT (ultra-high-resolution mode) for imaging of the temporal bone.
Fifty-four temporal bones in 27 patients were scanned with both a conventional MSCT and 128-section SST. After blinding and randomization of both examinations, 2 observers assessed the visualization of 38 anatomic structures (eg, various segments of the facial nerve canal, mallear ligaments) by using multiplanar reconstructions in the axial and coronal planes. The differences in evaluation scores obtained for the 2 techniques were analyzed by using a Wilcoxon signed rank test, with a P value of < .05 considered significant. For both methods, imaging time and radiation exposure were noted.
Overall visualization of anatomic structures did not differ significantly between the 2 techniques (P > .05). When we compared the anatomic structures separately, there was better visualization of the lateral mallear ligament with MSCT, whereas the cochlear septa were ranked higher with SST (P < .05). Imaging time and average DLP for MSCT were 12.3 seconds and 306 mGy cm, respectively; for SST, values they were 1 second and 64 mGy cm, respectively (ie, a dose reduction of 79%).
For imaging of the temporal bone with adequate diagnostic quality, 128-section SST can be used. The main advantages over MSCT are the dramatic reductions of imaging time and radiation exposure, which are particularly important when scanning uncooperative patients or children.
American Journal of Neuroradiology 03/2011; 33(4):E55-60. · 2.93 Impact Factor
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ABSTRACT: We report on an 80-year-old hypertensive patient with a left-sided high-grade carotid stenosis who developed transient monoparesis of the right arm after stenting of the carotid artery. Computed tomography (CT) of the brain (cranial CT) performed immediately after the symptomatic had begun showed a linear hyperdensity in the ipsilateral, precentral sulcus with a moderate, local brain swelling and edema. Transcranial doppler sonography revealed an accelerated post-interventional systolic blood flow velocity and in the ipsilateral medial cerebral artery compared to the preoperative value and an increased cerebral blood flow, so that the diagnosis of hyperperfusion syndrome with a subpial hematoma was confirmed. After strict blood pressure control and -reduction the neurological deficit regressed gradually and the hyperdensity had completely disappeared in control CCT after 15 h.
Der Radiologe 03/2011; 51(4):293-5. · 0.61 Impact Factor
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ABSTRACT: The aim of this retrospective clinical study was to compare the diagnostic accuracy of the novel 50 µm FFDM (full-field digital mammography) system (DR) with an established 70 µm system (DR) in the differential diagnosis between benign and malignant clusters of microcalcification (n=50) (BI-RADS™ classification 4/5) and to assess the possible incremental value of the 50 µm pixel-pitch on specificity.
From March 2009 to September 2009, 50 patients underwent full-field digital mammography (FFDM) (detector resolution 70 µm) (Novation, Siemens, Erlangen, Germany). As there were suspicious signs of microcalcification classified with BI-RADS™ 4/5 after diagnosis and preoperative wire localization, control images were made with the new FFDM system (detector: resolution 50 µm) (Amulet, Fujifilm, Tokyo, Japan) with the same exposure parameters. The diagnosis was determined after the operation by five radiologists with different experience in digital mammography from randomly distributed mediolateral views (monitor reading) whose results were correlated with the final histology of all lesions.
Histopathology revealed 19 benign and 31 malignant lesions in 50 patients after open biopsy. The results of the five readers showed a higher sensitivity of the new FFDM system (80.0%) in the ability to recognize malignant microcalcification in comparison to the established system (74.8%). The specificity (75.8 versus 71.6%) was slightly higher for the new system but these results were not statistically significant (p<0.001). Considering the diagnostic accuracy, the new system (detector: resolution 50 µm) was also slightly superior to the well-known system (detector: resolution 70 µm) (80.1% versus 76.4%).
Our study has shown that the new full-field digital mammography system using the novel detector compared with the already established FFDM system with respect to the assessment of microcalcification is at least equivalent.
Der Radiologe 11/2010; 51(2):126-9. · 0.61 Impact Factor
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ABSTRACT: The article describes an experimental phantom study of a system for digital full field mammography with a new digital detector with a double plate of pure selenium.
The experiments were carried out with the new full field digital mammography system Amulet from FujiFilm. This system has a new detector (18×24 cm(2)) on the basis of highly purified amorphous selenium (a-Se) with a pixel size of 50 µm. The x-rays are converted into electric signals in the first plate which are read into the second plate with the help of an optical switch and demonstrated in the form of an image. In this way a better pixel size/volume and signal-to-noise ratio should be achieved. The object of the investigation was the Wisconsin Mammographic Random Phantom, Model 152 A (Technical Performance Mo/Mo, 28 kV, 100 mAs). Five investigators with different experiences in mammography each received three images on a monitor with different random positions of the simulated lesions in the phantom for assessment. The detection rates were compared under the same conditions with the results of two other full field digital mammography systems.
The median detection rate for all images and investigators for the new doubled plated a-Se detector with optical switch was 98.7%. For both other systems with a-Si or and a-Se detectors the detection rate was 89.8% or 97.3%, respectively. There were no significant differences in the detection rate of the simulated breast lesions for all three systems considering the interobserver and intraobserver variation.
The first phantom study for the detection of simulated breast lesions with the new full field digital mammography system Amulet demonstrates equivalent results with the other systems used in the clinical routine. The trend towards superiority of the new system has to be confirmed in further clinical studies.
Der Radiologe 11/2010; 51(2):130-4. · 0.61 Impact Factor
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95th International Conference of the Radiological Society of North America, Chicago, USA; 11/2009
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ABSTRACT: Der Oropharynx stellt eine Schnittstelle zwischen Atem- und Speiseweg dar. Mit klinischer Inspektion bzw. Endoskopie ist eine
Vielzahl von Erkrankungen suffizient diagnostizierbar, bei Tumoren sollte jedoch zur Beurteilung der Tiefenausdehnung und
lymphogenen Ausbreitungsdiagnostik eine weiterführende Schnittbilddiagnostik erfolgen. In diesem Artikel werden unterschiedliche
Erkrankungen des Oropharynx vorgestellt und die bildgebenden Charakteristika der CT und MRT diskutiert. Besonderer Wert wird
auf die für die Therapieentscheidung essenziellen Details gelegt.
The oropharynx is an interface between the airway and the digestive tract. Clinical evaluation and endoscopy suffice for the
diagnosis of a variety of lesions, but tumors require cross-sectional imaging to assess local infiltration depth and lymphatic
spread. This article discusses different lesions of the oropharynx with respect to imaging characteristics of CT and MRI,
with a focus on resectability issues and decision-making.
Der Radiologe 12/2008; 49(1):27-35. · 0.61 Impact Factor
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ABSTRACT: The oropharynx is an interface between the airway and the digestive tract. Clinical evaluation and endoscopy suffice for the diagnosis of a variety of lesions, but tumors require cross-sectional imaging to assess local infiltration depth and lymphatic spread. This article discusses different lesions of the oropharynx with respect to imaging characteristics of CT and MRI, with a focus on resectability issues and decision-making.
Der Radiologe 12/2008; 49(1):27-35. · 0.61 Impact Factor
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ABSTRACT: Reduction of radiation exposure at an adequate image quality by optimizing the radiation quality for a new system of full-field digital mammography using a digital detector (a-Se).
The investigations were performed using a digital mammography system Novation (Siemens, Erlangen). The system was constructed with a bimetal anode (molybdenum and tungsten) and the possibility of changing the filter (molybdenum/rhodium). The test object was the Wisconsin Mammography Random Phantom Model 152 A (Radiation Measurements Inc.) of which images were acquired using the digital technique with the tungsten anode and rhodium filter at different tube voltages (26-35 kV) and tube loads (40-100 mAs) and compared to images in the molybdan/molybdan molybdenum/molybdenum technique. To quantify the image quality, we used the detection rate of the simulated lesions in the phantom.
Increasing the tube voltage significantly decreases the average glandular dose when using AEC (Automatic Exposure Control), i. e., constant detector dose. At the same time, the image quality decreases significantly with respect to the detection rate (26 kV, 1 mGy, 95.1 %; 35 kV, 0.7 mGy, 82.7 %). As a good compromise between the necessary diagnostic image quality and the lowest dose exposition, 28 kV and 60 mAs were selected for imaging with the tungsten/rhodium anode/filter combination. A further change to the tube load did not make sense because a decrease of 10 % resulted in a significant decrease in the detection rate while only a 2 % increase in detection rate was achieved for a 65 % increase in radiation exposure.
The results of this phantom study demonstrate that the routine use of the tungsten anode in combination with a rhodium filter for full-field digital mammography with an a-Se detector in contrast to a molybdan/molybdan molybdenum/molybdenum anode/filter combination results in a reduction of the average glandular dose of up to 30 % without loss of diagnostic image quality.
RöFo - Fortschritte auf dem Gebiet der R 06/2007; 179(5):487-91. · 2.76 Impact Factor
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ABSTRACT: Evaluation of the diagnostic value of breast specimen imaging with a digital mammographic system using a detector system with changeable pixel size compared to standard mode imaging in different monitor display modes.
Using the digital mammographic system SenoScan (Fischer Imaging, Denver, USA), 50 diagnostic breast specimens with microcalcifications were visualized in both standard mode (pixel size 54 microm) and high resolution mode (pixel size 27 microm). The resulting radiographs were displayed 1:1 on a monitor. Standard mode images (pixel size 54 microm) were additionally displayed in a 2:1 mode. A total of 5 readers with different mammographic experience analyzed the type of the microcalcifications on the basis of the different display modes. The images were presented randomly. The findings were subsequently compared to the histology.
The high resolution mode yielded slightly but not significantly better results than the standard mode on average for all 5 readers. Compared to a sensitivity of 80 % and a specificity of 72 % (PPV = 74 %, NPV = 78 %) in the standard mode, the high resolution mode provided a sensitivity of 86 % and a specificity of 74 % (PPV = 77 %, NPV = 83 %). The standard mode images on a 2:1 monitor display yielded 84 % and 74 % (PPV = 76 %, NPV = 82 %).
The high resolution mode did not significantly increase the sensitivity and specificity of the microcalcification reading. A similar improvement was achieved by the 2:1 display mode, i. e. digital monitor zooming. For the clinical situation this means that there is no diagnostic advantage from using a high resolution target view with this mammographic system.
RöFo - Fortschritte auf dem Gebiet der R 06/2007; 179(5):492-6. · 2.76 Impact Factor
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ABSTRACT: Solitary fibrous tumors (SFT) are rare, mostly fibroblastic tumors usually situated in the pleura. Extrapleural manifestations have been described. However, the oral cavity is an uncommon localisation of this tumor. We report the very unusual case of an SFT affecting the tongue that could be removed completely because of its clear delineation. Intraoperative incisional biopsies were used to exclude malignancy. For definitive classification of the tumor, additional histopathologic examinations had to be carried out. Because SFT exhibit malignant behavior only in exceptional cases and their recurrence after complete removal has never been encountered, surgery can focus on the preservation of undisturbed function of the tongue.
HNO 05/2007; 55(4):287-92. · 0.40 Impact Factor
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ABSTRACT: Solitre fibrse Tumoren (SFT) sind seltene und zumeist benigne fibroblastre Tumoren, die sich insbesondere in der Pleura manifestieren. Ein extrapleurales Auftreten von SFT ist zwar beschrieben worden, dennoch stellt die Mundhhle eine auergewhnliche Lokalisation fr den SFT dar. Es wird ber den sehr seltenen Fall eines SFT im Bereich der Zunge berichtet, der wegen seiner guten Abgrenzbarkeit vom umgebenden Gewebe problemlos entfernt werden konnte. Die intraoperative Schnellschnittdiagnostik diente zum Ausschluss eines malignen Prozesses. Fr die definitive histopathologische Zuordnung war die Durchfhrung zustzlicher immunhistologischer Untersuchungen hilfreich. Da sich SFT nur in Ausnahmefllen maligne verhalten und Rezidive nach vollstndiger Entfernung bisher nicht bekannt sind, kann der Schwerpunkt bei der Operation auf die Funktionserhaltung der Zunge gelegt werden.Solitary fibrous tumors (SFT) are rare, mostly fibroblastic tumors usually situated in the pleura. Extrapleural manifestations have been described. However, the oral cavity is an uncommon localisation of this tumor. We report the very unusual case of an SFT affecting the tongue that could be removed completely because of its clear delineation. Intraoperative incisional biopsies were used to exclude malignancy. For definitive classification of the tumor, additional histopathologic examinations had to be carried out. Because SFT exhibit malignant behavior only in exceptional cases and their recurrence after complete removal has never been encountered, surgery can focus on the preservation of undisturbed function of the tongue.
HNO 03/2007; 55(4):287-292. · 0.40 Impact Factor
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ABSTRACT: We describe the rare entity of an intraosseous meningioma arising in the mandible. The meningioma was found incidentally in an asymptomatic adult patient on dental radiography, mimicking other cystic-appearing jaw masses. The CT and MR imaging features of mandibular meningioma are reviewed with reference to prior published descriptions of this unusual entity.
American Journal of Neuroradiology 02/2007; 28(1):129-31. · 2.93 Impact Factor
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ABSTRACT: We prospectively evaluated the influence of different imaging techniques (time-of-flight MR angiography [TOF-MRA], contrast-enhanced MR angiography [CE-MRA], multisection CT angiography [CTA]) and postprocessing methods (maximum intensity projection [MIP], multiplanar reformation [MPR]) on carotid artery stenosis grading.
Fifty patients (34 men, 16 women) with symptomatic stenosis of the internal carotid artery were examined with a 16-section spiral CT and a 1.5T MR unit. Two MRA techniques were applied: 3D-TOF and CE-MRA. MPR was used for postprocessing with all modalities; MIP was used only with MRA. Four readers measured and calculated the percentage diameter stenosis independently according to NASCET criteria. The Wilcoxon test was used to measure interobserver variability, and the Friedman test was used to test the null-hypothesis of equality of the modalities.
The hypothesis for global equality was rejected (P < .001). TOF-MRA and CTA assessed with MPR showed the highest concordance (difference, 0.6%; confidence interval [CI], -3.0, 4.3%), and CE-MRA with MIP and CTA showed the lowest concordance in stenosis grading (difference, 7.0%; CI, 3.4, 10.6%). MPR resulted in lower degrees of stenosis than MIP for both MRA sequences, although not statistically significant (CE, -3.0%; CI, -6.6, 0.6%; TOF, -2.2%; CI, -5.8, 1.4%). When only studies with good or excellent image quality were considered, the differences decreased, but the trends remained.
Stenosis grading is dependent on the examination method and postprocessing technique. CTA and TOF-MRA evaluated with MPR revealed highest concordance.
American Journal of Neuroradiology 01/2007; 28(1):104-10. · 2.93 Impact Factor
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ABSTRACT: To compare the sensitivity of conventional two-dimensional (2D) projection imaging with tomosynthesis with respect to the detectability of mammographic phantom lesions.
Using a breast tomosynthesis prototype based on a commercial FFDM system (Siemens MAMMOMAT Novation), but modified for a wide angle tube motion and equipped with a fast read-out amorphous selenium detector, we acquired standard 2D images and tomosynthesis series of projection views. We used the Wisconsin mammographic random phantom, model RMI 152A. The anode filter combinations Mo/Mo and W/Rh at two different doses were used as typical radiographic techniques. Slice images through the phantom parallel to the detector were reconstructed with a distance of 1 mm employing a filtered back-projection algorithm. The image data sets were read by five radiologists and evaluated with respect to the detectability of the phantom details.
For all studied radiographic techniques, the detection rate in the tomosynthesis mode was 100 %, i. e. 75 true positive findings out of 75 possible hits. In contrast, the conventional projection mode yielded a detection rate between 80 and 93 % (corresponding to 60 and 70 detected details) depending on the dose and X-ray spectrum.
Tomosynthesis has the potential to increase the sensitivity of digital mammography. Overlapping structures from out-of-plane tissue can be removed in the tomosynthesis reconstruction process, thereby enhancing the diagnostic accuracy.
RöFo - Fortschritte auf dem Gebiet der R 01/2007; 178(12):1219-23. · 2.76 Impact Factor
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ABSTRACT: Fifty-one patients were examined with bone subtraction CT angiography (BSCTA). Data were acquired on 4-and 64-slice spiral CT systems. The post-processing method is based on fully automatic registration of non-enhanced and contrast-enhanced CT data and subsequent selective bone removal. Vascular structures and brain tissue are retained with the original CTA noise level. Image quality and delineation of the pathologic process were assessed and artifacts introduced by the bone removal process recorded. The bone subtraction algorithm worked successfully in all examinations. The processing time was 6 min on average. Image quality was rated excellent in 20 (39%), good in 26 (51%) and acceptable in 5 (10%) patients. Ophthalmic arteries were visible in 12 (24%) patients bilaterally, in 13 (25%) patients unilaterally and in 26 (51%) patients at least at the origin. BSCTA improved visualization of the infraclinoid ICA and the vertebral arteries. The depiction of stenosis of the extracranial ICA and supraclinoid aneurysms was not significantly improved. In patients with suspicion of sinus thrombosis, BSCTA and conventional CTA yielded similar results. To conclude, BSCTA improves the visualization of vessels with close contact to bone and can improve the diagnostic accuracy and therapy planning of infraclinoid aneurysms.
European Radiology 05/2006; 16(4):889-97. · 3.22 Impact Factor
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ABSTRACT: CT angiography (CTA) has been established for detection and therapy planning of intracranial aneurysms. The analysis of aneurysms at the level of the skull base, however, remains difficult because bone prevents a free view. We report initial clinical results of an approach for automatic bone elimination from CTA data.
Before the bone-removal process 2 datasets are acquired: nonenhanced spiral CT with reduced dose and contrast-enhanced CTA. The software automatically registers the nonenhanced data onto the CTA data and selectively removes bone. Vascular structures, as well as brain tissue, remain visible. In this study, we investigated 27 patients with 29 aneurysms, 13 of which were located at the skull base. 3D volume-rendered images with and without bone removal were reviewed and compared with digital subtraction angiography by 2 radiologists in consensus.
All supraclinoidal aneurysms were detected on 3D volume-rendered images of both CTA and bone-subtraction CT angiography (BSCTA). Four intracavernous and 3 paraclinoid aneurysms of the internal carotid artery were not visible or were only partially visible on conventional 3D CTA, whereas they could be optimally visualized with BSCTA. Bone removal was successful in all patients; the average additional time for postprocessing was 6.2 minutes. In 7 patients (26%), perfect bone removal without any artifacts was achieved. In most patients, some bone remnants were still present, though it did not disturb the 3D visualization of vascular structures.
BSCTA allows robust and fast selective elimination of bony structures, thus ascertaining a better analysis of arteries at the level of the skull base. This is useful for both detection and therapy planning of intracranial aneurysms.
American Journal of Neuroradiology 02/2006; 27(1):55-9. · 2.93 Impact Factor
