scholarly journals Error analysis for a free-hand three-dimensional ultrasound system for neuronavigation

1999 ◽  
Vol 6 (3) ◽  
pp. E7 ◽  
Author(s):  
Alexander Hartov ◽  
Symma D. Eisner ◽  
W. Roberts ◽  
Keith D. Paulsen ◽  
Leah A. Platenik ◽  
...  
Keyword(s):  
Mr Imaging ◽  
Three Dimensional ◽  
Ultrasound Image ◽  
Imaging Study ◽  
Ct Scanning ◽  
Preoperative Imaging ◽  
Ultrasound Images ◽  
Imaging Data ◽  
Extensive Evaluation ◽  
Ultrasound System

Image-guided neurosurgery that is directed by a preoperative imaging study, such as magnetic resonance (MR) imaging or computerized tomography (CT) scanning, can be very accurate provided no significant changes occur during surgery. A variety of factors known to affect brain tissue movement are not reflected in the preoperative images used for guidance. To update the information on which neuronavigation is based, the authors propose the use of three-dimensional (3-D) ultrasound images in conjunction with a finite-element computational model of the deformation of the brain. The 3-D ultrasound system will provide real-time information on the displacement of deep structures to guide the mathematical model. This paper has two goals: first, to present an outline of steps necessary to compute the location of a feature appearing in an ultrasound image in an arbitrary coordinate system; and second, to present an extensive evaluation of this system's accuracy. The authors have found that by using a stylus rigidly coupled to the 3-D tracker's sensor, they were able to locate a point with an overall error of 1.36 ± 1.67 mm (based on 39 points). When coupling the tracker to an ultrasound scanhead, they found that they could locate features appearing on ultrasound images with an error of 2.96 ± 1.85 mm (total 58 features). They also found that when registering a skull phantom to coordinates that were defined by MR imaging or CT scanning, they could do so with an error of 0.86 ± 0.61 mm (based on 20 coordinates). Based on their previous finding of brain shifts on the order of 1 cm during surgery, the accuracy of their system warrants its use in updating neuronavigation imaging data.

Coregistered intraoperative ultrasonography in resection of malignant glioma

2003 ◽  
Vol 14 (2) ◽  
pp. 1-5 ◽  
Author(s):  
Dimitrios C. Nikas ◽  
Alexander Hartov ◽  
Karen Lunn ◽  
Kyle Rick ◽  
Keith Paulsen ◽  
...  
Keyword(s):  
Ultrasound Image ◽  
Intraoperative Ultrasound ◽  
Image Data ◽  
Intraoperative Ultrasonography ◽  
Preoperative Imaging ◽  
Ultrasound Images ◽  
High Grade ◽  
Imaging Data ◽  
Patient Registration ◽  
High Grade Gliomas

Object The authors present their experience with coregistration of preoperative imaging data to intraoperative ultrasonography in the resection of high-grade gliomas, focusing on methodology and clinical observation. Methods Images were obtained preoperatively and coregistered to intraoperative hand-held ultrasound images by merging the respective imaging coordinate systems. After patient registration and imaging calibration, the authors computed the location on the magnetic resonance (MR) space of each pixel on an ultrasound image acquired in the operating room. The data were retrospectively reviewed in 11 patients with high-grade gliomas who underwent ultrasonography-assisted resection at our institution between June 2000 and December 2002. Satisfactory coregistration of intraoperative ultrasound and preoperative MR images was accomplished in all cases. Ultrasound and MR image data were closely congruent. Preoperative setup and intraoperative use of the system were unencumbering. Conclusions Based on these preliminary results, intraoperative ultrasonography is an attractive neuronavigational alternative, by which a less expensive and constraining imaging technique is used to acquire updated information. Optimal intraoperative guidance can be provided by the integration of this with other imaging studies.

Human aorta: preliminary results with virtual endoscopy based on three-dimensional MR imaging data sets.

Radiology ◽  
1996 ◽  
Vol 199 (1) ◽  
pp. 37-40 ◽  
Author(s):  
C P Davis ◽  
M E Ladd ◽  
B J Romanowski ◽  
S Wildermuth ◽  
J F Knoplioch ◽  
...  
Keyword(s):  
Mr Imaging ◽  
Three Dimensional ◽  
Virtual Endoscopy ◽  
Human Aorta ◽  
Data Sets ◽  
Imaging Data ◽  
Preliminary Results

Universal architecture of corneal segmental tomography biomarkers for artificial intelligence-driven diagnosis of early keratoconus

2021 ◽  
pp. bjophthalmol-2021-319309
Author(s):  
Gairik Kundu ◽  
Rohit Shetty ◽  
Pooja Khamar ◽  
Ritika Mullick ◽  
Sneha Gupta ◽  
...  
Keyword(s):  
Artificial Intelligence ◽  
Refractive Surgery ◽  
Three Dimensional ◽  
Area Under The Curve ◽  
Preoperative Imaging ◽  
Imaging Data ◽  
Wavefront Aberrations ◽  
Healthy Eyes ◽  
Fellow Eyes

AimsTo develop a comprehensive three-dimensional analyses of segmental tomography (placido and optical coherence tomography) using artificial intelligence (AI).MethodsPreoperative imaging data (MS-39, CSO, Italy) of refractive surgery patients with stable outcomes and diagnosed with asymmetric or bilateral keratoconus (KC) were used. The curvature, wavefront aberrations and thickness distributions were analysed with Zernike polynomials (ZP) and a random forest (RF) AI model. For training and cross-validation, there were groups of healthy (n=527), very asymmetric ectasia (VAE; n=144) and KC (n=454). The VAE eyes were the fellow eyes of KC patients but no further manual segregation of these eyes into subclinical or forme-fruste was performed.ResultsThe AI achieved an excellent area under the curve (0.994), accuracy (95.6%), recall (98.5%) and precision (92.7%) for the healthy eyes. For the KC eyes, the same were 0.997, 99.1%, 98.7% and 99.1%, respectively. For the VAE eyes, the same were 0.976, 95.5%, 71.5% and 91.2%, respectively. Interestingly, the AI reclassified 36 (subclinical) of the VAE eyes as healthy though these eyes were distinct from healthy eyes. Most of the remaining VAE (n=104; forme fruste) eyes retained their classification, and were distinct from both KC and healthy eyes. Further, the posterior surface features were not among the highest ranked variables by the AI model.ConclusionsA universal architecture of combining segmental tomography with ZP and AI was developed. It achieved an excellent classification of healthy and KC eyes. The AI efficiently classified the VAE eyes as ‘subclinical’ and ‘forme-fruste’.

Precision of navigated stereotactic probe implantation into the brainstem

2010 ◽  
Vol 5 (4) ◽  
pp. 350-359 ◽  
Author(s):  
Henrik Giese ◽  
Karl-Titus Hoffmann ◽  
Andreas Winkelmann ◽  
Florian Stockhammer ◽  
George I. Jallo ◽  
...  
Keyword(s):  
Mr Imaging ◽  
Ct Scan ◽  
Ct Scanning ◽  
Frameless Stereotaxy ◽  
Imaging Data ◽  
Stereotactic System ◽  
Brainstem Tumors ◽  
Probe Placement ◽  
Stereotactic Biopsies

Object The indications for stereotactic biopsies or implantation of probes for local chemotherapy in diffuse brainstem tumors have recently come under debate. The quality of performing these procedures significantly depends on the precision of the probes' placement in the brainstem. The authors evaluated the precision of brainstem probe positioning using a navigated frameless stereotactic system in an experimental setting. Methods Using the VarioGuide stereotactic system, 33 probes were placed into a specially designed model filled with agarose. In a second experimental series, 8 anatomical specimens were implanted with a total of 32 catheters into the pontine brainstem using either a suboccipital or a precoronal entry point. Before intervention in both experimental settings, a thin-sliced CT scan for planning was obtained and fused to volumetric T1-weighted MR imaging data. After the probe positioning procedures, another CT scan and an MR image were obtained to compare the course of the catheters versus the planned trajectory. The deviation between the planned and the actual locations was measured to evaluate the precision of the navigated intervention. Results Using the VarioGuide system, mean total target deviations of 2.8 ± 1.2 mm on CT scanning and 3.1 ± 1.2 mm on MR imaging were detected with a mean catheter length of 151 ± 6.1 mm in the agarose model. The catheter placement in the anatomical specimens revealed mean total deviations of 1.95 ± 0.6 mm on CT scanning and 1.8 ± 0.7 mm on MR imaging for the suboccipital approach and a mean catheter length of 59.5 ± 4.1 mm. For the precoronal approach, deviations of 2.2 ± 1.2 mm on CT scanning and 2.1 ± 1.1 mm on MR imaging were measured (mean catheter length 85.9 ± 4.7 mm). Conclusions The system-based deviation of frameless stereotaxy using the VarioGuide system reveals good probe placement in deep-seated locations such as the brainstem. Therefore, the authors believe that the system can be accurately used to conduct biopsies and place probes in patients with brainstem lesions.

scholarly journals Dynamic and three-dimensional transcranial sonography studies of an asymptomatic, cerebral convexity arachnoid cyst

1999 ◽  
Vol 7 (6) ◽  
pp. E12
Author(s):  
Felix Schlachetzki ◽  
Thilo Hölscher ◽  
O.W. Ullrich ◽  
M.D. Sabine Kübber ◽  
Wendelin Blersch ◽  
...  
Keyword(s):  
Mr Imaging ◽  
Arachnoid Cyst ◽  
Three Dimensional ◽  
Imaging Study ◽  
Transcranial Sonography ◽  
Dynamic Imaging ◽  
Noninvasive Methods ◽  
Benign Condition ◽  
Csf Circulation

Dynamic and three-dimensional transcranial sonography (dTCS and 3D-TCCS) examinations are complementary, noninvasive methods used in the assessment and follow up of patients with cerebrospinal fluid (CSF) circulation disorders. A 16-year-old female patient who presented with a space-occupying, cerebral convexity arachnoid cyst and recurrent tension-type headache underwent examination for raised intracranial pressure (ICP) by using a standard color-coded duplex sonography system attached to a personal computer–based system for 3D data acquisition. Conventional TCS identified the outer arachnoid membrane of the cyst, which undulated freely after short rotation of the head (“headshake maneuver”). The undulation was documented as a QuickTime movie that is included with this article. A 3D dataset was acquired and, by using a multiplanar reformatting reconstruction algorithm, the authors obtained images with excellent resolution that corresponded to an initial magnetic resonance (MR) imaging study. No differences on dTCS and 3D-TCS were detectable at follow up 9 months later, indicating normal ICP and a stable, benign condition. The use of 3D-TCCS and dTCS ultrasonography may complement other diagnostic procedures such as MR imaging and, thus, can improve management and therapeutic strategies for patients with CSF circulation disorders. In this report the authors present evidence of the excellent fine resolution and exact reproducibility of reconstructed ultrasound image planes derived from 3D datasets and the additional biomedical information from dynamic imaging.

Intraoperative three-dimensional visualization in microvascular decompression

2007 ◽  
Vol 107 (6) ◽  
pp. 1137-1143 ◽  
Author(s):  
Levent Tanrikulu ◽  
Peter Hastreiter ◽  
Regina Troescher-Weber ◽  
Michael Buchfelder ◽  
Ramin Naraghi
Keyword(s):  
Mr Imaging ◽  
Microvascular Decompression ◽  
3D Visualization ◽  
Cranial Nerves ◽  
Preoperative Imaging ◽  
Neurosurgical Procedures ◽  
Vascular Compression ◽  
Neurovascular Compression ◽  
Imaging Data ◽  
Neurovascular Structures

Object The authors systematically analyzed 3D visualization of neurovascular compression (NVC) syndromes in the operating room (OR) during microvascular decompression (MVD). Methods A total of 50 patients (26 women and 24 men) with trigeminal neuralgia (TN), hemifacial spasm (HFS), and glossopharyngeal neuralgia (GN) were examined and underwent MVD. Preoperative imaging of the neurovascular structures was performed using constructive interference in the steady state magnetic resonance (CISS MR) imaging, which consisted of 2D image slices. The 3D visualization of the neurovascular anatomy is generated after segmentaion of the CISS MR imaging in combination with direct volume rendering (DVR). The 3D representations were stored on a personal computer (PC) that was mounted on a mobile unit and transferred to the OR. During surgery, 3D visualization was applied by the surgeon with remotely controlled plasma-sterilized devices such as a wireless mouse and keyboard. The position of the 3D visualized neurovascular structures at the PC monitor was determined according to the intraoperative findings observed through the operating microscope. Results The system was stable during all neurosurgical procedures, and there were no operative or technical complications. Interactive adjustment of the 3D visualization guided by the view through the microscope permitted observation of the neurovascular relationships at the brainstem. Vessels covered by the cranial nerves could be noninvasively viewed by intraoperative 3D visualization. Postoperatively, the patients with TN and GN experienced pain relief, and the patients with HFS attained resolution of their facial tics. Vascular compression of nerves was explored in all 50 patients during MVD. Intraoperative 3D visualization delineated the compressing vessels and respective cranial nerves in 49 (98%) of 50 patients. Conclusions Interactive 3D visualization by DVR of high-resolution MR imaging data offered the opportunity for noninvasive virtual exploration of the neurovascular structures during surgery. An extended global survey of the neurovascular relationships was provided during MVD in each case. The presented method proved to be extremely advantageous for optimizing microneurosurgical procedures, supporting superior safety and improving the operative results when compared with the conventional strategy. This modality proved to be a very valuable teaching instrument and ensured the improvement of neurosurgical quality.

scholarly journals A patient-specific surgical simulator using preoperative imaging data: an interactive simulator using a three-dimensional tactile mouse

2014 ◽  
Vol 1 (1) ◽  
Author(s):  
Kazuhiro Endo ◽  
Naohiro Sata ◽  
Yasunao Ishiguro ◽  
Atsushi Miki ◽  
Hideki Sasanuma ◽  
...  
Keyword(s):  
Three Dimensional ◽  
Preoperative Imaging ◽  
Patient Specific ◽  
Imaging Data ◽  
Surgical Simulator

scholarly journals Deep Learning-Based Three-dimensional Transvaginal Ultrasound in Diagnosis of Intrauterine Adhesion

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Ji Li ◽  
Dan Liu ◽  
Xiaofeng Qing ◽  
Lanlan Yu ◽  
Huizhen Xiang
Keyword(s):  
Deep Learning ◽  
Learning Algorithm ◽  
Transvaginal Ultrasound ◽  
Three Dimensional ◽  
Ultrasound Image ◽  
Ultrasound Images ◽  
Diagnostic Efficiency ◽  
Research Subjects ◽  
Partial Differential ◽  
Intrauterine Adhesion

This study was aimed to enhance and detect the characteristics of three-dimensional transvaginal ultrasound images based on the partial differential algorithm and HSegNet algorithm under deep learning. Thereby, the effect of quantitative parameter values of optimized three-dimensional ultrasound image was analyzed on the diagnosis and evaluation of intrauterine adhesions. Specifically, 75 patients with suspected intrauterine adhesion in hospital who underwent the hysteroscopic diagnosis were selected as the research subjects. The three-dimensional transvaginal ultrasound image was enhanced and optimized by the partial differential equation algorithm and processed by the deep learning algorithm. Subsequently, three-dimensional transvaginal ultrasound examinations were performed on the study subjects that met the standards. The March classification method was used to classify the patients with intrauterine adhesion. Finally, the results by the three-dimensional transvaginal ultrasound were compared with the diagnosis results in hysteroscope surgery. The results showed that the HSegNet algorithm model realized the automatic labeling of intrauterine adhesion in the transvaginal ultrasound image and the final accuracy coefficient was 97.3%. It suggested that the three-dimensional transvaginal ultrasound diagnosis based on deep learning was efficient and accurate. The accuracy of the three-dimensional transvaginal ultrasound was 97.14%, the sensitivity was 96.6%, and the specificity was 72%. In conclusion, the three-dimensional transvaginal examination can effectively improve the diagnostic efficiency of intrauterine adhesion, providing theoretical support for the subsequent diagnosis and grading of intrauterine adhesion.

Resection of benign sciatic notch dumbbell-shaped tumors

2006 ◽  
Vol 105 (6) ◽  
pp. 873-880 ◽  
Author(s):  
Robert J. Spinner ◽  
Toshiki Endo ◽  
Kimberly K. Amrami ◽  
Eric J. Dozois ◽  
Dusica Babovic-Vuksanovic ◽  
...  
Keyword(s):  
High Resolution ◽  
Sciatic Nerve ◽  
Mr Imaging ◽  
Neurological Deficits ◽  
Leg Pain ◽  
Preoperative Imaging ◽  
Imaging Data ◽  
Cross Sectional ◽  
Sciatic Notch ◽  
One Stage

Object The operative management of combined intrapelvic and extrapelvic sciatic notch dumbbell-shaped tumors is challenging. The relatively rare occurrence of these tumors and the varied extent of disease have made it difficult for surgeons to establish definitive surgical indications or predict favorable neurological outcomes based on preoperative imaging data. Methods In the past 3 years, the authors treated five patients presenting with radiating leg pain as a result of benign sciatic notch dumbbell-shaped tumors. These tumors in three patients with unilateral leg symptoms were considered unresectable by other neurosurgeons because of presumed direct intrinsic neural involvement. After high-resolution magnetic resonance (MR) imaging demonstrated that the extensive tumors were separate from the sciatic nerve and the lumbosacral plexus, however, these patients underwent a combined one-stage transabdominal and posterior transgluteal complete resection. Normal neurological status was maintained postoperatively in these three patients, and after more than 1 year of postoperative follow up, there were no tumor recurrences. In two patients with bilateral symptoms and extensive tumor burden, serial MR images showed that innumerable tumors directly involved the entire cross-sectional area of the sciatic nerves and extended longitudinally to the lumbosacral plexuses. Tumor debulking or resection in these patients would have resulted in neurological deficits and would not have addressed their neuropathic pain, and therefore no surgery was performed. These two patients were treated pharmacologically and advised to monitor their tumor status over the course of their lifetimes in case of malignant transformation of the tumor. Conclusions A combined one-stage transabdominal and transgluteal approach allows safe resection of selected benign but extensive sciatic notch tumors. High-resolution MR imaging is a useful tool in the management of these tumors because it allows the surgeon to visualize the anatomical relationships of the tumor to the sciatic nerve. The authors believe that as this imaging technology advances, it will provide surgeons with a method to predict definitively which sciatic notch tumors displace rather than directly involve the sciatic nerve, and therefore indicate which tumors can be resected safely and completely.

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