A computerized tomography-computer graphics approach to stereotaxic localization

1979 ◽  
Vol 50 (6) ◽  
pp. 715-720 ◽  
Author(s):  
Russell A. Brown

✓ This paper describes the use of three-dimensional computer graphics to display structures visible in computerized tomography (CT) scans and to accurately determine optimum stereotaxic probe placement relative to those structures. A prototype Lucite stereotaxic frame designed for use in CT body scanners was fitted with a phantom consisting of small Lucite spheres representing intracranial tumors with diameters of 6 to 19 mm. A series of CT scans was obtained of the frame and phantom together. Edge outlines of the spheres were extracted from each scan in the series. A three-dimensional visual representation of the spheres was obtained by displaying their outlines from all CT scans. A superimposed visual simulation of the stereotaxic frame was adjusted interactively using several analog dials in order to simulate trajectory choice and probe depth before actual surgery. The frame settings and probe depth calculated by the graphical computer were then applied to the actual prototype frame in order to assess the accuracy of this combined CT-computer graphics approach to stereotaxic localization. The results of 22 such experiments and the implications for future clinical use of this new and precise localization technique are discussed.

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Gangadhar Ch ◽  
S. Jana ◽  
Sankararao Majji ◽  
Prathyusha Kuncha ◽  
Fantin Irudaya Raj E. ◽  
...  

Purpose For the first time in a decade, a new form of pneumonia virus, coronavirus, COVID-19, appeared in Wuhan, China. To date, it has affected millions of people, killed thousands and resulted in thousands of deaths around the world. To stop the spread of this virus, isolate the infected people. Computed tomography (CT) imaging is very accurate in revealing the details of the lungs and allows oncologists to detect COVID. However, the analysis of CT scans, which can include hundreds of images, may cause delays in hospitals. The use of artificial intelligence (AI) in radiology could help to COVID-19-positive cancer in this manner is the main purpose of the work. Design/methodology/approach CT scans are a medical imaging procedure that gives a three-dimensional (3D) representation of the lungs for clinical purposes. The volumetric 3D data sets can be regarded as axial, coronal and transverse data sets. By using AI, we can diagnose the virus presence. Findings The paper discusses the use of an AI for COVID-19, and CT classification issue and vaccination details of COVID-19 have been detailed in this paper. Originality/value Originality of the work is, all the data can be collected genuinely and did research work doneown methodology.


1995 ◽  
Vol 82 (6) ◽  
pp. 995-1001 ◽  
Author(s):  
Takehide Onuma ◽  
Yasuko Shimosegawa ◽  
Motonobu Kameyama ◽  
Hiroaki Arai ◽  
Kiyoshi Ishii

✓ The authors have treated five cases of severe head trauma in children in which abnormally high density along gyri, “gyral high density,” was seen on plain computerized tomography (CT) scans in the subacute stage of the injury. The prognosis in all cases was poor, with either severe disability or a vegetative state as the outcome due to significant brain atrophy following gyral high density. This pathology was classified into three clinical stages: 1) acute stage, cerebral ischemia in which there is diffuse low density of the cerebrum on CT scans (most marked on the 3rd and 4th days); 2) subacute stage, hemorrhagic infarction showing gyral high density on plain CT scans (between 1 and 4 weeks); and 3) chronic stage, brain atrophy (beginning 4 weeks after the trauma). In their consecutive series of head-injured patients (516 children, 1459 adults), the authors did not find gyral high density on CT scan in adults. This is probably due to the fact that adults who suffer the severe head trauma associated with diffuse brain swelling or diffuse brain edema cannot survive, thus making this gyral high density unique to children.


1984 ◽  
Vol 60 (5) ◽  
pp. 916-922 ◽  
Author(s):  
Bruce Mickey ◽  
Sissel Vorstrup ◽  
Bo Voldby ◽  
Helle Lindewald ◽  
Aage Harmsen ◽  
...  

✓ A noninvasive three-dimensional method for measuring cerebral blood flow (CBF), xenon-133 inhalation and emission computerized tomography, was used to investigate the CBF changes accompanying delayed neurological deterioration following subarachnoid hemorrhage (SAH). A total of 67 measurements were performed on 20 patients in Hunt and Hess' clinical Grades I to III in the first 21 days post SAH. Five patients with normal CBF tomograms on admission developed delayed neurological deficits in the 2nd week after hemorrhage, at which time repeat CBF tomograms in four patients revealed large areas of well defined regional flow decrease in the vascular territories of the anterior or middle cerebral arteries. Severe vasospasm was noted in three of these patients in whom arteriography was performed in the 2nd week post SAH. Diffuse bihemispheric CBF decreases were noted later in the course of delayed neurological deficits; however, measurements obtained soon after the onset of focal symptoms suggest that the only CBF decreases directly produced by vasospasm in Grade III patients are regional changes.


1999 ◽  
Vol 91 (3) ◽  
pp. 424-431 ◽  
Author(s):  
Yasuo Murai ◽  
Ryo Takagi ◽  
Yukio Ikeda ◽  
Yasuhiro Yamamoto ◽  
Akira Teramoto

Object. The authors confirm the usefulness of extravasation detected on three-dimensional computerized tomography (3D-CT) angiography in the diagnosis of continued hemorrhage and establishment of its cause in patients with acute intracerebral hemorrhage (ICH).Methods. Thirty-one patients with acute ICH in whom noncontrast and 3D-CT angiography had been performed within 12 hours of the onset of hemorrhage and in whom conventional cerebral angiographic studies were obtained during the chronic stage were prospectively studied. Noncontrast CT scanning was repeated within 24 hours of the onset of ICH to evaluate hematoma enlargement.Findings indicating extravasation on 3D-CT angiography, including any abnormal area of high density on helical CT scanning, were observed in five patients; three of these demonstrated hematoma enlargement on follow-up CT studies. Thus, specificity was 60% (three correct predictions among five positives) and sensitivity was 100% (19 correct predictions among 19 negatives). Evidence of extravasation on 3D-CT angiography indicates that there is persistent hemorrhage and correlates with enlargement of the hematoma.Regarding the cause of hemorrhage, five cerebral aneurysms were visualized in four patients, and two diagnoses of moyamoya disease and one of unilateral moyamoya phenomenon were made with the aid of 3D-CT angiography. Emergency surgery was performed without conventional angiography in one patient who had an aneurysm, and it was clipped successfully.Conclusions. Overall, 3D-CT angiography was found to be valuable in the diagnosis of the cause of hemorrhage and in the detection of persistent hemorrhage in patients with acute ICH.


1981 ◽  
Vol 55 (5) ◽  
pp. 718-724 ◽  
Author(s):  
J. Jaap van der Sande ◽  
Jan J. Veltkamp ◽  
Ria J. Boekhout-Mussert ◽  
G. Jan Vielvoye

✓ Coagulation studies (plasma fibrinogen, ethanol gelation test, and fibrin-fibrinogen degradation product concentration) and computerized tomography (CT) scan examinations were performed in 55 patients with blunt head injury. The frequency of abnormalities in both coagulation study results and CT scans was higher in patients with severe clinical features and clinical course than in less severely injured patients; in these same patients the coagulation results were abnormal (64%) more frequently than the CT scans (40%). Very high fibrin-fibrinogen degradation product (FDP) concentrations were found to be associated with combined hemorrhagic lesions and mass effect on CT scans, but not with a specific localization of braintissue damage. It was concluded that: 1) FDP concentration reflects the amount of brain-tissue damage rather than its location, and 2) in the absence of other possible causes of disseminated intravascular coagulation, coagulation studies may be more sensitive than CT scanning in demonstrating brain contusion.


1990 ◽  
Vol 73 (3) ◽  
pp. 392-395 ◽  
Author(s):  
Varun Laohaprasit ◽  
Daniel L. Silbergeld ◽  
George A. Ojemann ◽  
Joseph M. Eskridge ◽  
H. Richard Winn

✓ Contrast-enhanced computerized tomography (CT) is frequently utilized immediately after surgery to determine the presence of residual tumor, but the response of nontumor brain tissue is unclear. Consequently, the authors investigated the postoperative CT contrast enhancement in six patients undergoing lobectomy for epilepsy. Preoperative CT scans were obtained in all cases and revealed no enhancing lesions. All patients underwent craniotomy with electrocorticography while awake, followed by lobectomy. Computerized tomography scans with and without administration of contrast material were obtained on postoperative Days 3, 7, and 30. Edema, artifact, and enhancement of the resection margins were seen on postoperative Days 3 and 7, but had resolved in all patients by Day 30. It is concluded that postoperative CT scans for assessment of residual tumor are best obtained at 30 days or thereafter, when normal brain does not enhance and edema and artifact have diminished.


1989 ◽  
Vol 71 (6) ◽  
pp. 929-931 ◽  
Author(s):  
Müfit Kalelioğlu ◽  
Gönül Aktürk ◽  
Fadiil Aktürk ◽  
Sezer Ş. Komsuoğlu ◽  
Kayhan Kuzeyü ◽  
...  

✓ Cerebral myiasis with a 10-day history of convulsions due to an intracerebral hematoma caused by a Hypoderma bovis larva is reported in an 8-year-old child. Computerized tomography (CT) showed the hematoma in a right parieto-occipital location. The H. bovis larva and the extensive intracerebral hematoma were discovered during surgery. Among human parasitoses, cerebral myiasis is rare: a review of the literature revealed only two reports, one published in 1969 and one in 1980. This is the first case that has been diagnosed as cerebral myiasis with exact identification of the Hypoderma bovis larva both from the CT scans and at surgery in a patient during life.


1981 ◽  
Vol 54 (1) ◽  
pp. 125-127 ◽  
Author(s):  
Patrick M. Foy ◽  
Leandro Lozada ◽  
Malcolm D. Shaw

✓ A patient with an arteriovenous malformation and giant venous aneurysm was erroneously diagnosed as having an oligodendroglioma on computerized tomography (CT). This case highlights some of the problems of interpretation of CT scans and the dangers of misinterpretation, particularly in the surgical context.


1989 ◽  
Vol 70 (2) ◽  
pp. 280-281 ◽  
Author(s):  
Henry Hirschberg

✓ A method is described for marking the site of a tumor on the scalp based on information from computerized tomography (CT) scans. The technique employs a syrinx-shaped array of radiopaque catheters of varying length taped to the patient's scalp for visualization on the CT scan. Fiducial markings on the CT images allow the transfer of the tumor's location directly onto the scalp. The device can be placed anywhere on the scalp, including in a parasagittal position.


2002 ◽  
Vol 97 (6) ◽  
pp. 1322-1332 ◽  
Author(s):  
J. Pablo Villablanca ◽  
Parizad Hooshi ◽  
Neil Martin ◽  
Reza Jahan ◽  
Gary Duckwiler ◽  
...  

Object. Middle cerebral artery (MCA) aneurysms can be difficult to detect and characterize. The authors describe the utility and impact of helical computerized tomography (CT) angiography for the evaluation of aneurysms in this location, and compare this modality with digital subtraction (DS) angiography and intraoperative findings. Methods. Two hundred fifty-one patients with suspected cerebral aneurysms underwent CT angiography. Two-dimensional multiplanar reformatted images and three-dimensional CT angiograms were examined by two independent readers in a blinded fashion. Results were compared with findings on DS angiograms to determine the relative efficacy of these modalities in the detection and characterization of aneurysms. Questionnaires completed by neurosurgeons and endovascular therapists were used to determine the impact of CT angiograms on aneurysm management. Twenty-eight patients harboring 31 MCA aneurysms and 26 patients without aneurysms were identified using CT angiography. The sensitivity of CT angiography and DS angiography for MCA aneurysms was 97%; both techniques showed 100% specificity. In 76% of evaluations, the CT angiography studies provided information not available on DS angiography examinations. For the characterization of aneurysms, CT angiography was rated superior (72%) or equal (20%) to DS angiography in 92% of cases evaluated (p < 0.001). Computerized tomography angiography was evaluated as the only study needed for patient triage in 82% of cases (p < 0.001), and as the only study needed for treatment planning in 89% of surgically treated (p < 0.001) and in 63% of endovascularly treated cases (p < 0.001). The information acquired on CT angiograms changed the initial treatment plan in 24 (67%) of these 36 complex lesions (p < 0.01). The aneurysm appearance intraoperatively was identical or nearly identical to that seen on CT angiograms in 17 (89%) of 19 of the surgically treated cases. Conclusions. Computerized tomography angiography has unique advantages over DS angiography and is a viable alternative to the latter modality in the diagnosis, triage, and treatment planning in patients with MCA aneurysms.


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