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Peri-operative brachial plexus injury following self-positioning for stereotactic radiofrequency ablation. Anaesth Rep 2019; 7:79-82. [PMID: 32051957 DOI: 10.1002/anr3.12024] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/05/2019] [Indexed: 11/11/2022] Open
Abstract
A 71-year-old woman with a known accessory cervical rib and distinct scoliosis was scheduled for elective, percutaneous stereotactic radiofrequency ablation of a non-resectable intrahepatic cholangiocellular carcinoma. Patient positioning and fixation using a Bluebag fixation system (Medical Intelligence, Schwabmünchen, Germany) and a dedicated adjustable armrest were customised in the patient while awake. In order to provide safe conditions for mask ventilation and tracheal intubation, the patient was returned to standard supine positioning without changing the position of the armrest. Following the induction of general anaesthesia, the patient's arm was returned to the previously defined position. Upon completion of the procedure and emergence from anaesthesia, the patient immediately reported symptoms of severe brachial plexus damage. Therefore, we suggest that awake positioning according to current recommendations does not completely preclude the possibility of neurologic injury.
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A rare case of Epstein-Barr virus-associated hepatosplenic smooth muscle tumors after kidney transplantation. Transpl Infect Dis 2018; 20:e12860. [PMID: 29427352 DOI: 10.1111/tid.12860] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2017] [Revised: 10/04/2017] [Accepted: 11/20/2017] [Indexed: 12/28/2022]
Abstract
A 27-year old caucasian male was diagnosed 2.7 years after kidney transplantation with Epstein-Barr virus (EBV)-associated smooth muscle tumors in liver and spleen. The reduction in immunosuppression and conversion from tacrolimus to sirolimus did not lead to a regression of the tumors. Additionally, the patient developed a cellular rejection of his renal allograft, which was successfully treated. A combined approach with stereotactic radiofrequency ablation (SRFA) and surgical resection was effective in the treatment of the tumors.
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The Effect of Concurrent Tumor Bed Boost Delivery on Acute and Late Toxicity in Patients With Breast Cancer: Update of a Systematic Review. Int J Radiat Oncol Biol Phys 2016. [DOI: 10.1016/j.ijrobp.2016.06.679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Abstract
CLINICAL ISSUE Increasing understanding of the anatomy and physiology of neural structures has led to the development of surgical and percutaneous neurodestructive methods in order to target and destroy various components of afferent nociceptive pathways. The dorsal root ganglia and in particular the ganglia of the autonomous nervous system are targets for radiological interventions. The autonomous nervous system is responsible for the regulation of organ functions, sweating, visceral and blood vessel-associated pain. STANDARD RADIOLOGICAL METHODS Ganglia of the sympathetic chain and non-myelinized autonomous nerves can be irreversibly destroyed by chemical and thermal ablation. PERFORMANCE Computed tomography (CT)-guided sympathetic nerve blocks are well established interventional radiological procedures which lead to vasodilatation, reduction of sweating and reduction of pain associated with the autonomous nervous system. ACHIEVEMENTS AND PRACTICAL RECOMMENDATIONS Sympathetic blocks are applied for the treatment of various vascular diseases including critical limb ischemia. Other indications for thoracic and lumbar sympathectomy include complex regional pain syndrome (CRPS), chronic tumor associated pain and hyperhidrosis. Neurolysis of the celiac plexus is an effective palliative pain treatment particularly in patients suffering from pancreatic cancer. Percutaneous dorsal root ganglion rhizotomy can be performed in selected patients with radicular pain that is resistant to conventional pharmacological and interventional treatment.
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Comparison of Two Electromagnetic Navigation Systems For CT-Guided Punctures: A Phantom Study. ROFO-FORTSCHR RONTG 2016; 188:470-8. [PMID: 27074422 DOI: 10.1055/s-0042-103691] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
PURPOSE We compared the targeting accuracy and reliability of two different electromagnetic navigation systems for manually guided punctures in a phantom. MATERIALS AND METHODS CT data sets of a gelatin filled plexiglass phantom were acquired with 1, 3, and 5 mm slice thickness. After paired-point registration of the phantom, a total of 480 navigated stereotactic needle insertions were performed manually using electromagnetic guidance with two different navigation systems (Medtronic Stealth Station: AxiEM; Philips: PercuNav). A control CT was obtained to measure the target positioning error between the planned and actual needle trajectory. RESULTS Using the Philips PercuNav, the accomplished Euclidean distances were 4.42 ± 1.33 mm, 4.26 ± 1.32 mm, and 4.46 ± 1.56 mm at a slice thickness of 1, 3, and 5 mm, respectively. The mean lateral positional errors were 3.84 ± 1.59 mm, 3.84 ± 1.43 mm, and 3.81 ± 1.71 mm, respectively. Using the Medtronic Stealth Station AxiEM, the Euclidean distances were 3.86 ± 2.28 mm, 3.74 ± 2.1 mm, and 4.81 ± 2.07 mm at a slice thickness of 1, 3, and 5 mm, respectively. The mean lateral positional errors were 3.29 ± 1.52 mm, 3.16 ± 1.52 mm, and 3.93 ± 1.68 mm, respectively. CONCLUSION Both electromagnetic navigation devices showed excellent results regarding puncture accuracy in a phantom model. The Medtronic Stealth Station AxiEM provided more accurate results in comparison to the Philips PercuNav for CT with 3 mm slice thickness. One potential benefit of electromagnetic navigation devices is the absence of visual contact between the instrument and the sensor system. Due to possible interference with metal objects, incorrect position sensing may occur. In contrast to the phantom study, patient movement including respiration has to be compensated for in the clinical setting. KEY POINTS • Commercially available electromagnetic navigation systems have the potential to improve the therapeutic range for CT guided percutaneous procedures by comparing the needle placement accuracy on the basis of planning CT data sets with different slice thickness. Citation Format: • Putzer D, Arco D, Schamberger B et al. Comparison of Two Electromagnetic Navigation Systems For CT-Guided Punctures: A Phantom Study. Fortschr Röntgenstr 2016; 188: 470 - 478.
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Ultralow-dose computed tomography imaging for surgery of midfacial and orbital fractures using ASIR and MBIR. Int J Oral Maxillofac Surg 2015; 44:441-6. [PMID: 25680629 DOI: 10.1016/j.ijom.2015.01.011] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Accepted: 01/15/2015] [Indexed: 10/24/2022]
Abstract
The influence of dose reductions on diagnostic quality using a series of high-resolution ultralow-dose computed tomography (CT) scans for computer-assisted planning and surgery including the most recent iterative reconstruction algorithms was evaluated and compared with the fracture detectability of a standard cranial emergency protocol. A human cadaver head including the mandible was artificially prepared with midfacial and orbital fractures and scanned using a 64-multislice CT scanner. The CT dose index volume (CTDIvol) and effective doses were calculated using application software. Noise was evaluated as the standard deviation in Hounsfield units within an identical region of interest in the posterior fossa. Diagnostic quality was assessed by consensus reading of a craniomaxillofacial surgeon and radiologist. Compared with the emergency protocol at CTDIvol 35.3 mGy and effective dose 3.6 mSv, low-dose protocols down to CTDIvol 1.0 mGy and 0.1 mSv (97% dose reduction) may be sufficient for the diagnosis of dislocated craniofacial fractures. Non-dislocated fractures may be detected at CTDIvol 2.6 mGy and 0.3 mSv (93% dose reduction). Adaptive statistical iterative reconstruction (ASIR) 50 and 100 reduced average noise by 30% and 56%, and model-based iterative reconstruction (MBIR) by 93%. However, the detection rate of fractures could not be improved due to smoothing effects.
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Ultralow Dose CT Imaging for Navigated Skull Base Surgery Using ASIR and MBIR-2D and 3D Image Quality. Skull Base Surg 2014. [DOI: 10.1055/s-0034-1384131] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Ablation und Embolisation von Lebertumoren. ROFO-FORTSCHR RONTG 2014. [DOI: 10.1055/s-0034-1372997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Comparison of freehand-navigated and aiming device-navigated targeting of liver lesions. Int J Med Robot 2013; 10:35-43. [PMID: 23832927 DOI: 10.1002/rcs.1505] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/19/2013] [Indexed: 01/02/2023]
Abstract
BACKGROUND Accurate needle placement is crucial for the success of percutaneous radiological needle interventions. We compared three guiding methods using an optical-based navigation system: freehand, using a stereotactic aiming device and active depth control, and using a stereotactic aiming device and passive depth control. METHODS For each method, 25 punctures were performed on a non-rigid phantom. Five 1 mm metal screws were used as targets. Time requirements were recorded, and target positioning errors (TPE) were measured on control scans as the distance between needle tip and target. RESULTS Time requirements were reduced using the aiming device and passive depth control. The Euclidian TPE was similar for each method (4.6 ± 1.2-4.9 ± 1.7 mm). However, the lateral component was significantly lower when an aiming device was used (2.3 ± 1.3-2.8 ± 1.6 mm with an aiming device vs 4.2 ± 2.0 mm without). DISCUSSION Using an aiming device may increase the lateral accuracy of navigated needle insertion.
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Ultrasound guided versus CT-controlled pararadicular injections in the lumbar spine: a prospective randomized clinical trial. AJNR Am J Neuroradiol 2012; 34:466-70. [PMID: 22821925 DOI: 10.3174/ajnr.a3206] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
BACKGROUND AND PURPOSE Injection therapies play a major role in the treatment of lower back pain and are to date performed mainly under CT- or fluoroscopic guidance. We conducted this study to evaluate the accuracy, time savings, radiation doses, and pain relief of US-guided pararadicular injections versus CT-controlled interventions in the lumbar spine in a prospective randomized clinical trial. MATERIALS AND METHODS Forty adult patients were consecutively enrolled and assigned to a US or CT group. US-guided pararadicular injections were performed on a standard US device by using a broadband curved-array transducer (9-4 or 5-1 MHz). In the in-plane technique, the needle was advanced through the respective segmental intertransverse ligament. The needle tip position was verified by CT. The CT-guided approaches were performed under standardized procedures by using the CT-positioning laser function. RESULTS The accuracy of US-guided interventions was 90%. The mean time to final needle placement in the US group was 4.0 ± 1.8 minutes, and in the CT group, 7.6 ± 2.1 minutes. The mean radiation doses, including CT confirmation for study purposes only, were 20.3 ± 9.0 mGy cm for the US group and 42.6 ± 36.1 mGy cm for the CT group. Both groups showed the same significant pain relief (P < .05) without relevant "intermethodic" differences of pain relief (P > .05). CONCLUSIONS US-guided pararadicular injections show a therapeutic effect similar to that in the time-consuming, expensive, ionizing CT or fluoroscopically guided pararadicular injections and result in a significant reduction of procedure time expenditure and avoidance of radiation.
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Accuracy of Cone-Beam Computed Tomography (CBCT) and Multislice Computed Tomography (MSCT)-Guided Skull Base Surgery Using Different Registration Methods. Skull Base Surg 2012. [DOI: 10.1055/s-0032-1314336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Influence of Modern Low-Dose Multislice Spiral Computed Tomography on Target Registration Errors in Image-Guided Skull Base Surgery. Skull Base Surg 2012. [DOI: 10.1055/s-0032-1314337] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Diagnostic value of software-based image fusion of computed tomography and F18-FDG PET scans in patients with malignant lymphoma. ScientificWorldJournal 2012; 2012:821694. [PMID: 22654631 PMCID: PMC3357935 DOI: 10.1100/2012/821694] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2011] [Accepted: 12/26/2011] [Indexed: 11/17/2022] Open
Abstract
AIM The purpose of this study was to evaluate the accuracy of 2-deoxy-2-[fluorine-18]fluoro-D-glucose (FDG) positron emission tomography (PET), computed tomography (CT), and software-based image fusion of both modalities in the imaging of non-Hodgkin's lymphoma (NHL) and Hodgkin's disease (HD). METHODS 77 patients with NHL (n = 58) or HD (n = 19) underwent a FDG PET scan, a contrast-enhanced CT, and a subsequent digital image fusion during initial staging or followup. 109 examinations of each modality were evaluated and compared to each other. Conventional staging procedures, other imaging techniques, laboratory screening, and follow-up data constituted the reference standard for comparison with image fusion. Sensitivity and specificity were calculated for CT and PET separately. RESULTS Sensitivity and specificity for detecting malignant lymphoma were 90% and 76% for CT and 94% and 91% for PET, respectively. A lymph node region-based analysis (comprising 14 defined anatomical regions) revealed a sensitivity of 81% and a specificity of 97% for CT and 96% and 99% for FDG PET, respectively. Only three of 109 image fusion findings needed further evaluation (false positive). CONCLUSION Digital fusion of PET and CT improves the accuracy of staging, restaging, and therapy monitoring in patients with malignant lymphoma and may reduce the need for invasive diagnostic procedures.
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Substantial Dose Reduction in Modern Multi-Slice Spiral Computed Tomography (MSCT)-Guided Craniofacial and Skull Base Surgery. ROFO-FORTSCHR RONTG 2012; 184:136-42. [DOI: 10.1055/s-0031-1281971] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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Navigated open, laparoscopic, and percutaneous liver surgery. MINERVA CHIR 2011; 66:435-453. [PMID: 22117210] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Resection and thermal ablation procedures are frequently used for the treatment of primary and secondary liver tumors. Various tools for the virtual planning of liver resections and ablation are available and some of them are already used clinically. Resection planes and ablation volumes can be optimized for sufficient safety margins while preserving a maximal amount of functional liver tissue. Connecting the pre-operative planning with intraoperative guidance based on the 3D imaging data would be desirable. Interactive image guided surgery enables visualization of the actual spatial location of the surgical instrument on preoperatively acquired images in real time. However, extensive soft tissue deformations during open and laparoscopic surgical and ablative procedures may occur, causing unacceptable inaccuracies. The current focus of research is the adaptation of the preoperative virtual planning models to surgery by using intraoperative imaging and biomechanical models. In contrast to open and laparoscopic surgical procedures percutaneous punctures can be performed with high accuracy under stereotactic conditions. Important prerequisites include patient immobilization, respiratory triggering and intraoperative imaging. Due to the high accuracy of probe positioning the virtual preoperative ablation plan can be precisely transferred into the real patient. A total of 350 patients with primary and secondary liver tumors have already successfully been treated with stereotactic radiofrequency ablation (SRFA). Due to its low complication rates and similar local recurrence and survival rates as compared to conventional surgery SRFA is an attractive alternative for the treatment for primary and secondary liver tumors.
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Thermoablation des HCC. ROFO-FORTSCHR RONTG 2011. [DOI: 10.1055/s-0031-1278751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Die Genauigkeit der Diskonnektion des endotrachealen Tubus zu Kontrolle der Atembewegung für perkutane Leberinterventionen. ROFO-FORTSCHR RONTG 2011. [DOI: 10.1055/s-0031-1279363] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Stereotaktische Radiofrequenzablation von kolorektalen Lebermetastasen - Langzeitüberleben. ROFO-FORTSCHR RONTG 2011. [DOI: 10.1055/s-0031-1279145] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Technische Effektivität, Komplikationsrate und Performerabhängigkeit der Stereotaktischen Radiofrequenzablation (SRFA) von Leberherden. ROFO-FORTSCHR RONTG 2011. [DOI: 10.1055/s-0031-1279096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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F18-Cholin PET in der Rezidivdiagnostik bei Patienten mit serologischem Rezidiv nach radikaler Prostatektomie: hat eine vorausgegangene Antiandrogentherapie einen Einfluss auf die Ergebnisse der PET? ROFO-FORTSCHR RONTG 2011. [DOI: 10.1055/s-0031-1279599] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Magnetic Resonance Imaging of Radiofrequency Current-Induced Coagulation Zones in the Ex Vivo Bovine Liver. ROFO-FORTSCHR RONTG 2010; 182:690-7. [DOI: 10.1055/s-0029-1245373] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Integration of multimodality imaging and surgical navigation in the management of patients with refractory epilepsy. A pilot study using a new minimally invasive reference and head-fixation system. Acta Neurochir (Wien) 2010; 152:365-78. [PMID: 19960357 DOI: 10.1007/s00701-009-0386-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2008] [Accepted: 03/18/2009] [Indexed: 10/20/2022]
Abstract
OBJECTIVE To review the experience with a new system (VBH system) for minimally invasive frameless stereotactic guidance, acting as a common platform to provide multimodal image integration and surgical navigation in a consecutive series of 25 patients who underwent surgery for drug-resistant seizures. METHODS The usefulness of the VBH system for integrating all images to produce one dataset and for intraoperative instrument guidance and navigation was judged semiquantitatively in a three-tiered scale (+, ++, +++). Seizure outcome was classified according to Engel. RESULTS The presurgical evaluation extended over 21.2 months (mean). A total of 141 registrations of images were performed (mean 5.6 per patient, range: 2 to 16). In 19 (76%) of 25 patients structural data fused with functional data were used for the presurgical workup. Six patients proceeded directly to navigated resection. Nineteen patients (76%) underwent invasive recording, of whom 13 underwent resective surgery. In seven patients (28%) the combination of multimodal image fusion and intra-operative stereotactic guidance was judged "essential" (+++) to remove the epileptogenic zone. Integration of all images to form one dataset was "essential" (+++) for decision making in 15 and "helpful" (++) in 4 patients (overall 76% of patients). Intraoperative use of frameless neuronavigation was "essential" (+++) in ten and "helpful" (++) in all remaining patients. Eighty percent of the patients achieved satisfactory seizure outcome after 1 year. CONCLUSION The VBH system is a safe and effective non-invasive tool for repetitive imaging, multimodal image fusion and frameless stereotactic surgical navigation in candidates for epilepsy surgery.
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Preliminary experience with (68)Ga-DOTA-lanreotide positron emission tomography. THE QUARTERLY JOURNAL OF NUCLEAR MEDICINE AND MOLECULAR IMAGING : OFFICIAL PUBLICATION OF THE ITALIAN ASSOCIATION OF NUCLEAR MEDICINE (AIMN) [AND] THE INTERNATIONAL ASSOCIATION OF RADIOPHARMACOLOGY (IAR), [AND] SECTION OF THE SOCIETY OF... 2010; 54:52-60. [PMID: 20168286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
AIM Positron emission tomography (PET) of (68)Ga-radiolabelled (SST) somatostatin receptor (R) binding peptides has recently been evaluated in SSTR positive tumor patients. First promising results in lung and thyroid tumor patients with (111)In-DOTA-Lanreotide (DOTA-LAN) scintigraphy have been described. We report our first experience with (68)Ga-labeled DOTA-LAN. METHODS Eleven patients (3 non small cell lung cancer [NSCLC], 3 small cell lung cancer [SCLC], 3 radioiodine negative thyroid cancer, 2 medullary thyroid cancer [MTC]) were investigated. After intravenous injection of 75-150 MBq (68)Ga-DOTA-LAN dynamic studies were acquired over the tumor site for the first 40 min with a dedicated PET scanner in 3 patients, and 2 partial body scans were acquired at 20 and 50 min p.i. in 2 patients. Whole body acquisitions at 90 min after injection were acquired in all 11 patients. Image reconstruction was performed by iterative reconstruction utilizing additional transmission scans for attenuation correction. Vital parameters were recorded during the PET study and up to 24 h p.i. Blood and urinary sampling was done up to 4 hr after tracer injection in 8 patients. PET results were compared to conventional imaging techniques (CIT), i.e. computed tomography (CT) and/or magnetic resonance imaging (MRI). In 5 patients, (68)Ga-DOTA-LAN was compared with 2-[(18)F]fluoro-2-deoxy-D-glucose ((18)F-FDG). RESULTS After intravenous (i.v.) injection of (68)Ga-DOTA-LAN the radioactivity in the blood rapidly decreased to less then 20% of the injected dose (ID) within the first 20 min and further decreased to less than 9% ID after 4 h. A cumulative urinary excretion of (68)Ga-DOTA-LAN up to 29.2 + or - 13.2% ID at 4 h was found. No acute side effects were observed. Tumor sites were visualized already during the first min after injection. Comparison of positron emission tomography (PET) and CIT showed concordant results in 3/8 patients and partial concordant results in 5/8 patients with matched results for the primary/recurrent tumor, mediastinal lymph nodes, or adrenal gland metastases. Partial concordant results were seen for the lung, bone, liver and cervical lymph node metastases. Micronodular metastases of the lung and the cerebrum were not visualized by (68)Ga-DOTA-LAN PET. The maximal standardized uptake values of the lung and bone tumor lesions ranged from 6 to 8 g/ml at 90 min p.i.. CONCLUSIONS (68)Ga-DOTA-LAN visualized the majority of tumor lesions. Further studies are required to assess the clinical value, and to obtain the best imaging protocol of this new PET SSTR tracer.
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[Multiple cavernous hemangioma progressing in size in a cirrhotic liver]. ROFO-FORTSCHR RONTG 2009; 182:357-9. [PMID: 19953432 DOI: 10.1055/s-0028-1109908] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Flexibility of Head Positioning and Head Fixation Provided by a Novel System for Non-invasive Maxillary Fixation and Frameless Stereotaxy: Technical Note. ACTA ACUST UNITED AC 2009; 52:144-8. [DOI: 10.1055/s-0028-1105922] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Accuracy and feasibility of frameless stereotactic and robot-assisted CT-based puncture in interventional radiology: a comparative phantom study. ROFO-FORTSCHR RONTG 2009; 181:851-8. [PMID: 19517342 DOI: 10.1055/s-0028-1109380] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
PURPOSE To compare the accuracy of frameless stereotactic and robot-assisted puncture in vitro based on computed tomography (CT) imaging with a slice thickness of 1, 3, and 5 mm. MATERIALS AND METHODS 300 punctures were carried out with help of the Atlas aiming device guided by the optical navigation system Stealth Station TREONplus and 150 punctures were guided by the robotic assistance system Innomotion. Conically shaped rods were punctured with Kirschner wires. The accuracy was evaluated on the basis of control CTs by measuring the Euclidean distance between the wire tip and target and the normal distance between the target and wire. RESULTS With the Stealth Station a mean Euclidean distance of 1.94 +/- 0.912, 2.2 +/- 1.136, and 2.74 +/- 1.166 mm at a slice thickness of 1, 3 and 5 mm, respectively, was reached. The mean normal distance was 1.64 +/- 0.919, 1.84 +/- 1.189, and 2.48 +/- 1.196 mm, respectively. The Innomotion system resulted in a mean Euclidean distance of 1.69 +/- 0.772, 1.91 +/- 0.673, and 2.30 +/- 0.881 mm, respectively, while the mean normal distance was 1.42 +/- 0.78), 1.60 +/- 0.733, and 1.98 +/- 1.002 mm, respectively. A statistical significance between accuracies with both systems with 1 mm and 3 mm slices could not be detected (p > 0.05). At a slice thickness of 5 mm, the robot was significantly more accurate, but not as accurate as when using thinner slices (p < 0.05). The procedure time is longer for the Innomotion system ( 30 vs. 18 min), and the practicability is higher with the Stealth Station. CONCLUSION The systems yield comparable accuracy. A slice thickness of 3 mm is adequate. Application of both methods in patient treatment can be expected to be safe and reliable.
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Accuracy and clinical use of a novel aiming device for frameless stereotactic brain biopsy. MINIMALLY INVASIVE NEUROSURGERY : MIN 2008; 51:361-369. [PMID: 19061150 DOI: 10.1055/s-0028-1085424] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Aiming devices enable the use of neuronavigation systems for rigid instrument guidance mimicking the possibilities of a frame-based system without having a stereotactic frame affixed to the skull. The aim of the presented work was to investigate the phantom targeting accuracy of the Vertek aiming device (Medtronic Inc., Louisville, USA) and whether it can be safely and accurately applied in a concept of minimally invasive brain biopsy in which multi-modal image fusion, image-to-patient registration and head immobilization were based on a non-invasive vacuum mouthpiece. A plastic model of a head with 20 target beads broadly distributed around the head volume was used for determination of CT-based targeting accuracy. Every target was punctured 5 times totaling 100 needle positionings. Accuracy was evaluated on postoperative CT scans with the needles in place. The mean normal deviation (n = 100) was 1.5 +/- 0.8 mm and the mean angle of deviation was 1.1 +/- 0.7 degrees. In a preliminary clinical series in ten patients diagnostic biopsy sampling of intracranial lesions with a median diameter of 28 mm (range: 12-90 mm) could be achieved in all patients and no biopsy related complications were recorded. The experimental results showed a similar accuracy to frame-based stereotaxy. The device facilitates trajectory alignment via two pivot joints and the actual depth and location of the biopsy needle can be monitored. Within the limitations of a preliminary study, brain biopsy may be accurately and safely performed for lesions > or = 12 mm.
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John Anthony Seymour-Jones. West J Med 2008. [DOI: 10.1136/bmj.a2602] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Comparison of two novel fluoroscopy-based stereotactic methods for cervical pedicle screw placement and review of the literature. EUROPEAN SPINE JOURNAL : OFFICIAL PUBLICATION OF THE EUROPEAN SPINE SOCIETY, THE EUROPEAN SPINAL DEFORMITY SOCIETY, AND THE EUROPEAN SECTION OF THE CERVICAL SPINE RESEARCH SOCIETY 2008; 17:564-75. [PMID: 18210169 DOI: 10.1007/s00586-008-0584-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2007] [Revised: 10/16/2007] [Accepted: 12/21/2007] [Indexed: 10/22/2022]
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Primary ovarian carcinoid heart disease curatively treated with a two-stage procedure. Thorac Cardiovasc Surg 2008; 55:467-9. [PMID: 17902075 DOI: 10.1055/s-2006-955908] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
Primary ovarian carcinoid disease with cardiac involvement is a very rare syndrome, which requires interdisciplinary management. We report on a patient with primary ovarian carcinoid tumor with severe tricuspid valve insufficiency who was curatively treated after successful tumor resection and tricuspid valve replacement.
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Navigation in der interventionellen Radiologie. ROFO-FORTSCHR RONTG 2008. [DOI: 10.1055/s-2008-1073189] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Abstract
BACKGROUND Severe complications in endoscopic paranasal sinus surgery are rare, however, when they occur they are often fatal. Injuries to the optic nerve or the internal carotid artery mostly occur after penetration of the sphenoid sinus' anterior wall. METHODS We present the robot system "A 73" with its newly designed 4-canal-microendoscope and special instruments that meets the demands of endoscopic paranasal sinus surgery. A fully automated perforation of the sphenoid sinus' anterior wall was performed in five cadaveric specimens. RESULTS The sphenoid sinus' anterior wall could be perforated without damaging the surrounding structures in all cases. Subsequently, the approach was enlarged to the desired diameter using telemanipulation mode. The analysis of both the transformation error and intraopertive accuracy showed values in the submillimeter range. CONCLUSIONS Using a newly developed robotic system, a fully automated perforation of the sphenoid sinus' anterior wall was performed precisely and reproducibly. This approach can be enlarged in a telemanipulation mode.
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Computerunterstützte Radiofrequenzablation von Osteoidosteomen. ROFO-FORTSCHR RONTG 2005. [DOI: 10.1055/s-2005-868181] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Computerunterstützte Punktion des Foramen ovale zur Platzierung von Tiefenhirnelektroden bei Epilepsiepatienten. ROFO-FORTSCHR RONTG 2005. [DOI: 10.1055/s-2005-868323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Virtuelle CT_Bildfusion: Bedeutung für die Erfassung der aortalen Stentmigration. ROFO-FORTSCHR RONTG 2005. [DOI: 10.1055/s-2005-867934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Genauigkeit der CT-SPECT-Bildfusion in der präoperativen Abklärung der Nebenschilddrüsenadenome. ROFO-FORTSCHR RONTG 2005. [DOI: 10.1055/s-2005-867883] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Computerunterstützte Radiofrequenzablation des Ganglion Gasseri bei Patienten mit Trigeminusneuralgie. ROFO-FORTSCHR RONTG 2005. [DOI: 10.1055/s-2005-868282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Abstract
We report the first case of robot-assisted thoracoscopic resection of a mediastinal parathyroid adenoma in the aorto-pulmonary window. Intervention planning was based on preoperative CT-MIBI image fusion, a new imaging modality that enabled reliable and precise localization of the parathyroid. The technique consists of taking MIBI-SPECT and CT separately, using a fixation unit that provides reproducible positioning of the patients head and neck. The data sets are then superimposed upon each other using special software. After the localization process, a minimally invasive operation was performed using the DaVinci operating robot. The procedure proved not only to be feasible but also safe and not time-consuming. The postoperative course was uneventful, and the patient was discharged 4 days postoperatively. Compared to conventional thoracoscopic surgery, the robotic operating system provides better visualization of the operating field and facilitates the movement of the instruments. Precise preoperative imaging enables the careful planning of robot-assisted surgery for ectopic parathyroids located at relatively inaccessible regions such as the anterior mediastinum.
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Schockraummanagement: Rahmenbedingungen, Organisation, Integration. ROFO-FORTSCHR RONTG 2004. [DOI: 10.1055/s-2004-827434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Neuroendoscopy based on computer assisted adjustment of the endoscope holder in the laboratory. ACTA ACUST UNITED AC 2003; 46:208-14. [PMID: 14506564 DOI: 10.1055/s-2003-42348] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
OBJECTIVE We present our initial clinical experience with a novel technique of frameless stereotactic neuroendoscopy using a neuronavigation system, a specially designed aiming device (endoscope holder/targeting device) combined with a vacuum-mouthpiece based head holder. Due to the reproducibility of patient immobilization in the fixation system, the endoscope holder can be adjusted in the laboratory in the absence of the patient. METHODS An individual vacuum-mouthpiece was fabricated. The patients were scanned with an external reference frame attached to this mouthpiece and the images were transferred to the neuronavigation system. Determination of the path, mouthpiece-based registration and adjustment of the targeting device were performed the day before surgery in the absence of the patient. In the OR the patient was repositioned and the endoscope was introduced through the preadjusted aiming device to the precalculated depth. RESULTS The novel technique was successfully used for frameless endoscopic navigation in five patients. Three endoscopic third ventriculostomies in adults, one endoscopic septostomy due to unilateral hydrocephalus in an adult female patient and one endoscopic ventriculo-cysto cisternostomy in a 20-month-old girl with a suprasellar arachnoid cyst, were performed with excellent clinical results and without technical complications. CONCLUSION Our initial experience indicates that frameless stereotaxy, in combination with a relocatable head holder and a special targeting device, allows for precise and preplanned advancement of the neuroendoscope, reducing or even eliminating intraoperative registration and endoscope trajectory adjustments, thus substantially reducing OR time. Due to the non-invasive but rigid immobilization method, neuronavigation can also be performed in children under 2 years of age.
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Abstract
PURPOSE To evaluate a modified algorithm in the diagnostic management of polytraumatized patients by using whole body multislice CT (MSCT) as primary diagnostic tool. MATERIAL AND METHODS Between June 1999 and October 2000 532 polytraumatized patients were referred to the emergency department. 336 polytraumatized patients were primarily evaluated using whole body MSCT according to the "Innsbruck Emergency Algorithm." MSCT is performed immediately after cardiovascular stabilization of the patient. During the initial stabilization period free intraabdominal fluid is excluded or demonstrated by abdominal ultrasound. Time-consuming conventional radiographs are omitted with exception of an optimal chest X-ray. In patients with suspected or obvious arterial injuries or fractures the multislice-CT-dataset is used to perform 2D and 3D reconstructions in order to optimize visualization of additional skeletal and vascular injuries. RESULTS By means of whole body MSCT it was possible to detect all injuries. The diagnostic advantage of whole body MSCT as compared to conventional X-ray was analyzed in 111 consecutive polytraumatized patients with an injury severity score (ISS) of 34.77. The early use of MSCT shortened the time for diagnostic work-up substantially (approximately 50%). CONCLUSION Whole body multislice-CT used as primary diagnostic tool in the management of polytraumatized patients allows for a fast, accurate and comprehensive diagnostic work-up.
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Efficacy and one year follow up of argon plasma coagulation therapy for ablation of Barrett's oesophagus: factors determining persistence and recurrence of Barrett's epithelium. Gut 2002; 51:776-80. [PMID: 12427775 PMCID: PMC1773469 DOI: 10.1136/gut.51.6.776] [Citation(s) in RCA: 101] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 06/26/2002] [Indexed: 12/29/2022]
Abstract
INTRODUCTION Barrett's epithelium (BE) has malignant potential. Neither acid suppression nor antireflux surgery produce consistent or complete regression of the metaplastic epithelium. Endoscopic thermoablation with argon plasma coagulation (APC) offers a different approach but factors influencing its outcome have not been systematically examined. AIM To assess the efficacy of APC and factors influencing initial and one year outcome. METHODS Fifty patients, mean age 61.4 years, mean BE length 5.9 cm (range 3-19), underwent APC therapy at four weekly intervals while receiving proton pump inhibitor (PPI) therapy. BE margins were marked by India ink tattooing and extent was documented by grid drawings, photography, and 2 cm interval quadrantic jumbo biopsies. Twenty four hour ambulatory oesophageal pH studies were done while on PPIs before and after APC therapy, and Bilitec bilirubin monitoring after APC completion. RESULTS A total of 68% of patients achieved >90% BE ablation after a median of four APC sessions. Persistent BE (>10% original BE area) was associated with longer initial BE length despite more APC sessions. Persistent acid and bile reflux on PPIs, although commoner in this group, were not significantly different from those successfully ablated. Fifteen of 34 patients (44%) with successful macroscopic clearance had buried glands, present in 8.3% of a total of 338 biopsies. At the one year follow up, only 32% of those with initial successful ablation showed no recurrence. BE recurred or increased in most with mean segment length increases of 1.1 cm and 1.6 cm, respectively, in patients with previous full ablation and those with persistent BE. The presence of buried glands did not predict BE recurrence. Patients who reduced their PPI dose had significantly greater BE recurrence. CONCLUSIONS APC is most effective for shorter segment BE ablation but "buried" glands do occur. Recurrence of BE is common at one year, especially in those with initial persistent and/or long segment BE and those who reduce their PPI dose.
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Abstract
PURPOSE To evaluate a modified algorithm in the diagnostic management of polytraumatized patients by using whole body multislice CT (MSCT) as primary diagnostic tool. MATERIAL AND METHODS Between June 1999 and October 2000 532 polytraumatized patients were referred to the emergency department. 336 polytraumatized patients were primarily evaluated using whole body MSCT according to the "Innsbruck Emergency Algorithm". MSCT is performed immediately after cardiovascular stabilization of the patient. During the initial stabilization period free intraabdominal fluid is excluded or demonstrated by abdominal ultrasound. Time-consuming conventional radiographs are omitted with exception of an optional chest X-ray. In patients with suspected or obvious arterial injuries or fractures the multislice-CT-dataset is used to perform 2D and 3D reconstructions in order to optimize visualization of additional skeletal and vascular injuries. RESULTS By means of whole body MSCT it was possible to detect all injuries. The diagnostic advantage of whole body MSCT as compared to conventional X-ray was analyzed in 111 consecutive polytraumatized patients with an injury severity score (ISS) of 34.77. The early use of MSCT shortened the time for diagnostic work-up substantially (approximately 50%). CONCLUSION Whole body multislice-CT used as primary diagnostic tool in the management of polytraumatized patients allows for a fast, accurate and comprehensive diagnostic work-up.
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Use of neuronavigation and electrophysiology in surgery of subcortically located lesions in the sensorimotor strip. J Neurol Neurosurg Psychiatry 2002; 72:378-81. [PMID: 11861700 PMCID: PMC1737780 DOI: 10.1136/jnnp.72.3.378] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVES Subcortical lesions in the sensorimotor strip are often considered to be inoperable. The purpose of this study was to evaluate the usefulness of a combined approach for surgery in this region, aided by a robotic neuronavigation system under electrophysiological control. METHODS In a prospective study on 10 patients, space occupying lesions in the sensorimotor central area were removed using the Surgiscope robotic navigation system and the Nicolet Viking IV electrophysiological system. RESULTS Precise tumour localisation with the neuronavigation system and the information on the patient's cortical motor distribution obtained by bipolar cortical stimulation led to postoperative improvement in motor function in all but one patient. Seven of the patients had focal, defined pathology (four metastases; two cavernoma; one aspergilloma). CONCLUSION Due to the implementation of two recent technologies, surgery of lesions in the subcortical sensorimotor region can be performed with greater confidence.
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Virtual endoscopy for planning neuro-endoscopic intraventricular surgery. MINIMALLY INVASIVE NEUROSURGERY : MIN 2002; 45:24-31. [PMID: 11932821 DOI: 10.1055/s-2002-23580] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
Abstract
To evaluate the usefulness of virtual endoscopy (VE) in planning neuroendoscopic intraventricular surgeries, the technique was applied in 20 of 22 consecutive procedures. Thirteen endoscopic third ventriculostomies (ETV) in 12 patients, 3 endoscopic colloid cyst removals, 1 third ventricular arachnoidal cyst fenestration, 1 endoscopic ventricul-cysto-cisternostomy (suprasellar arachnoidal cyst), 1 endoscopic tumor biopsy, one third ventricular gross total tumor removal and 2 septostomies at the foramen of Monro due the septal occlusion were performed. Contrast medium-enhanced MR images (3DMPRAGE, Siemens, Germany) were semi-automatically segmented with a surface-rendering technique ("Navigator" software, General Electric Medical, Buc, France) to produce the virtual endoluminal views. Surgery was performed with cerebral ventriculoscopes by Wolf (Richard Wolf, Knittlingen, Germany). VE was feasible in all patients and the virtual endoscopic images were comparable with the real intraventricular views obtained by standard rod lens systems. After contrast medium administration intra- and paraventricular vessels such as the thalamocaudate vein, the septal veins, the basilar artery and its branches (distal BA complex) and the choroid plexus were identified on the virtual endoscopic images. In 8 patients, the additional anatomic information provided by VE profoundly influenced surgical planning. VE provides the neurosurgeon with additional morphological information supporting the planning process of neuroendoscopic intraventricular surgeries, contributing to the safety of the procedures.
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Abstract
Five studies have been conducted with the atypical anti-psychotic amisulpride (100-1200 mg/day) involving 1358 patients with acute exacerbations of schizophrenia; four studies were short-term (4-8 weeks), double-blind studies and one was a 12-month, open, randomized comparison. Amisulpride improved positive symptoms consistently, and changes were more pronounced than with haloperidol, flupenthixol and risperidone; amisulpride showed a more rapid onset of action compared to haloperidol, and improvement in negative symptoms was more effective than with any comparator. An optimum response was obtained with amisulpride doses 400-800 mg/day. The long-term study confirmed the usefulness of amisulpride for maintenance treatment in schizophrenia, with a clear advantage over haloperidol, leading to better functioning and quality of life. Amisulpride caused fewer neurological side-effects than conventional anti-psychotics and less weight gain than risperidone, both of which are crucial factors for long-term compliance.
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Abstract
PURPOSE To determine the feasibility of using ultrasonography (US) for evaluation of a radial nerve injury associated with humeral shaft fracture. MATERIALS AND METHODS In a prospective study, 11 consecutive patients with sensorimotor radial deficiency after distal humeral fracture were evaluated with conventional radiography, US, electroneurography, and electromyography. Surgical repair of the fracture and nerve inspection were performed in five patients. The remaining six patients were successfully treated conservatively. The US appearance of the radial nerve was studied in 10 healthy volunteers and in the noninjured arm of the 11 patients for comparison. RESULTS In five patients, US findings of a severely damaged radial nerve were confirmed at surgical nerve inspection. In one patient, the nerve was entrapped between fragments. One patient had a complete nerve dissection, one had a lacerated nerve from a loose compression plate, and one had a nerve riding on the edge of a bone fragment. In the fifth patient who underwent surgical inspection, the nerve was buried in the callus. In the six patients treated conservatively, US showed continuity of the nerve. CONCLUSION US may be useful for accurate evaluation of the radial nerve in patients with nerve palsy associated with humeral shaft fracture.
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Abstract
PURPOSE The purpose of study was to compare patient dose applying singleslice- and multislice-spiral CT. METHODS The examinations were performed with a singleslice-spiral CT (Highspeed Advantage; GE Medical Systems; Milwaukee, USA) and with a multislice CT systems (LightSpeed QX/i GE Medical Systems; Milwaukee, USA). For the determination of the radiation exposure (absorbed dose) a selection of most executed protocols (thorax-helical, abdomen-helical, petrous bone-axial, head-axial) were simulated using an Alderson Rando Phantom. The dose was determined by means of lithiumfluorid-thermoluminiscence dosimeters (TLD-GR 200). RESULTS For thorax and abdomen protocols higher energy dose values could be found using a multislice CT. On the average the energy dose values were increased by 2.6 on an average in relation to single slice spiral CT. The energy dose values of the multisclice CT using head protocols could be reduced by 30% in relation to single slice spiral CT due to suitable parameter selections. The energy dose applying a petrous bone protocol resulted in an average increase by a factor 1.5 using a multislice CT. CONCLUSION Using the new multislice CT technique protocol strategies must be optimized regarding the patient doses. Users can operate critically in the sense of the radiation protection only if they are aware of the occurring dose amounts to the patient.
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Abstract
Within the last decade computed tomography has become an important instrument for skeletal diagnosis. In this study the value of helical CT-scan was compared with plan X-rays and conventional tomography in 45 patients having sustained an intraarticular tibia plateau fracture. Between plan roentgenogramms and CT-scan the fracture classification according to the AO-classification was changed in 40% of all patients, in 39 cases the amount of impression or dislocation increased with a mean of 4.2 mm. Especially tiny fragments were better visible and therefore responsible for the shift of many B1 fractures to group B3. The difference between conventional tomography and computed tomography was less impressive, a change of fracture classification could be observed in only 6.7% of all cases.
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