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Comparison of linear and non-linear soft tissue models with post-operative CT scan in maxillofacial surgery  [PDF]
Matthieu Chabanas,Yohan Payan,Christophe Marecaux,Pascal Swider,Franck Boutault
Physics , 2006,
Abstract: A Finite Element model of the face soft tissue is proposed to simulate the morphological outcomes of maxillofacial surgery. Three modelling options are implemented: a linear elastic model with small and large deformation hypothesis, and an hyperelastic Mooney-Rivlin model. An evaluation procedure based on a qualitative and quantitative comparison of the simulations with a post-operative CT scan is detailed. It is then applied to one clinical case to evaluate the differences between the three models, and with the actual patient morphology. First results shows in particular that for a "simple" clinical procedure where stress is less than 20%, a linear model seams sufficient for a correct modelling.
Relative Frequency of Maxillofacial Fracture in CT-Scan Radiographs in Shahid Sadoghi and Shahid Rahnemoun Emergency Departments in Yazd from 2007 Till 2010
Ezoddini Ardakan,Nafisi Moghadam,Chavoshian,Hashemian
Journal of Shahid Sadoughi University of Medical Sciences , 2012,
Abstract: Introduction: Technologic improvement and increased production of car and motorcycle have led to the increased incidence of maxillofacial trauma all around the world. Injuries of maxillofacial region include fractures of mandible, maxilla, zygoma, orbit and nasal bone, which is due to different etiologic factors such as motor vehicle accidents, quarreling, fall, and sport-related and work- related accidents. The Purpose of this study was to evaluate the frequency of maxillofacial fracture in CT-scan radiographs in Shahid Sadoghi and Shahid Rahnemon emergency departments in Yazd from 2007 till 2010. Methods: In this retrospective study we assessed the medical files of all patients with maxillofacial traumawho were admitted at Shahid Sadoughi and Shahid Rahnemoun hospitals in ENT and surgery wards during a 4-year period. The information from patients' medical file and CT scan radiographs were recorded. At last 372 patients were evaluated. Results: In this study the age of patients showed to be between 20 and 29. Eighty six and fourteen percent of patients were males and females, respectively. Among all fractures, mandible fracture was the most frequent one (50.8%). The most frequent etiologic factor was accident (59%) and the most frequent outcome was partial recovery (46.4%) and death was observed in 0.8% of individuals. Conclusion: Results of this study showed that the most frequent etiologic factor of trauma to maxillofacial region is motor vehicle accident similar to other developing countries.
Diagnostic Role of 18F-FECH-PET/CT Compared with Bone Scan in Evaluating the Prostate Cancer Patients Referring with Biochemical Recurrence  [PDF]
Mustafa Takesh,Khaldoun Odat Allh,Stefan Adams,Christian Zechmann
ISRN Oncology , 2012, DOI: 10.5402/2012/815234
Abstract: 18F-FECH-PET/CT has been proved to be an imaging agent for prostate carcinoma. However, its role in detecting the bone metastases is still blurred owing to the lack of related studies. The purpose of our study was to assess the efficacy of PET with 18F-ethylcholine in assessing the bone status and to compare the results with that of conventional bone scan findings. For this purpose, we selected 37 patients (mean age ), who had been referred for restaging purposes due to biochemical recurrences and underwent both 18F-FECH-PET/CT and bone scan in a short interval. Generally 18 patients out 37 patients referred with biochemical relapse were confirmed to have bone involvement. From 18 confirmed bone involvement cases, 18F-FECH-PET/CT identified correctly the bone involvement in 15 cases with overall sensitivity of 83.3%. On the other hand, bone scan identified 17 out of 18 confirmed cases with overall sensitivity of 94.4%. The lesion-related results show that the sensitivity of each investigation differs with the anatomical regions, and by comparing both results, 18F-FECH-PET/CT was mostly superior to bone scan; however, without a statistical significance ( ). In conclusion, no significant gain in sensitivity was achieved using bone scan compared with 18F-FECH-PET/CT. 1. Introduction Carcinoma of the prostate is the most common malignancy in men with increased incidence rates owing to the population ageing and the improvement of diagnostic procedures. The early detection of the bone metastases is of value in making decision regarding the treatment plan, which may vary extremely according to the bone status. The likelihood of the bone metastases at the first diagnosis varies with the histological score and serum level of prostate-specific antigen, and it is possible to some extent to estimate the degree of tumor spread in the light of the PSA value. Bone involvement is much less frequently involved with low PSA level, so that the bone staging is not recommended with PSA less than 10?ng/mL, except if there are known bone disorders which may later cause false positive findings [1–3]. However, in patients with PSA relapse after primary therapy it is not easy to be guessed based on PSA values whether the bone involvement or another involvement is behind a PSA rising. In established skeletal involvement, there is a need of effective imaging method to monitor the status progress. Bone scan is the widely used screening technique for assessing the bone status in the most malignancies, and it shows mostly high sensitivity in detecting the bone involvement. However,
Neoplastic Invasion of Laryngeal Cartilage: Evaluation by CT Scan
Mahrooz Malek,Hashem Sharifian,Habib Mazaher,Shervin Sharifkashany
Iranian Journal of Radiology , 2009,
Abstract: "nIntroduction: To assess the accuracy of pre-operative spiral CT for the prediction of laryngeal cartilage invasion in patients with squamous cell carcinoma (SCC) of the larynx, and also to evaluate CT factors that would accurately indicate cartilage invasion. "nMaterials and Methods: In this prospective study, 37 patients with squamous cell carcinoma of the larynx underwent contrast-enhanced CT-scan before laryngectomy. The following CT criteria were evaluated in thyroid, arytenoids and cricoid cartilages: sclerosis, lysis and tumor visible on both sides. After laryngectomy, histologic findings were correlated with findings that were obtained on the CT scans at each level. "nResults: Histologically, 48 of 139 cartilages (34%) were evaluated. According to the diagnostic criteria on CT in each specific cartilage there were some variations in sensitivity (36%-81%) and specificity (38%-100%). Applied to all cartilages, the combination of sclerosis and lysis in all cartilages with an extralaryngeal invasion of the thyroid cartilage yielded on the overall sensitivity of 89%; specificity of 76%; positive predictive value of 68%; negative predictive value of 91% and an accuracy of 80%. "nConclusion: Pre-operative CT scan is an accurate test for the evaluation of laryngeal cartilage invasion, especially, when a combination of sclerosis, lysis and extralaryngeal involvement exists.
A comparative study of the diagnostic accuracy on Waters view with CT scan in detecting midface fractures
Panjnoush M.,Shirani Gh.,Jozghanbari P.
Journal of Dental Medicine , 2006,
Abstract: Background and Aim: In recent years, CT scan has become available as an alternative to conventional radiography. To date, the utility of Waters view in detecting midface fractures has been rarely evaluated. The aim of this study was to compare the diagnostic accuracy and reliability of Waters radiography with CT scan in detecting midface fractures. Materials and Methods: In this tests evaluation study, waters view and CT scan were performed for 42 patients with midface fracture admitted to maxillofacial surgery department of Shariati hospital. All images were observed and interpreted by an oral and maxillofacial radiologist and an oral and maxillofacial surgeon. Sensitivity, specificity and reliability for Waters view in detecting midface fractures were assessed by Cohen’s kappa test. Results: Sensitivity and specificity for Waters view in detection of midface fratures by the radiologist were 31.79% and 95.35% and by the surgeon were 29.59% and 93.75% respectively. The highest reliability in CT scan and Waters view (in nasal fractures) by the radiologist was 66.67% and was 58.33% by the surgeon in buttress of zygoma. The highest agreement rate between the radiologist and the surgeon for CT scan was in zygomatic arch (78.95%) and for Waters view was in nasal fracture (62.5%). Conclusion: Based on the results of this study, the specificity of Waters view is sufficient to diagnose fractures of lateral orbital wall, infraorbital rim, orbital floor, zygomatic arch, frontozygomatic suture, lateral wall of maxillary sinus and Lefort II fracture. The specificity is not sufficient to diagnose fractures of medial orbital wall and anterior, posterior and medial wall of maxillary sinus. Detection of these midface fractures needs other conventional radiographies or CT scan.
The Professional Medical Journal , 2008,
Abstract: Objective: To evaluate the comparative diagnostic efficacy of Ultrasound,CT-Scan, and Laparoscopy in the diagnosis of non-palpable undescended testes in pediatric patients. Design:Comparative study. Setting: Surgical and pediatric surgical department of B V Hospital (QAMC) Bahawalpur and AlliedHospital Faisalabad. Period: From April 2006 to April 2007. Materials & Method: A total forty boys with non palpabletestis were subjected to Ultrasound, CT-Scan and diagnostic laparoscopy in a period of one year. The patients above12 years and with cardiovascular anomalies were excluded from the study. Laparoscopy was performed under generalanesthesia and findings were compared with Ultrasound and CT-Scan. Sensitivity and specificity of each werecalculated. Results: Diagnostic accuracy of Ultrasound was 25%, CT-Scan was 64% and Laparoscopy was 100%.Sensitivity was found to be 20%, 63% and 100% and specificity was 10%. 50% and 100% for Ultrasound, CT-Scan andLaparoscopy, respectively. Conclusion: Diagnostic laparoscopy is far more superior as compared to Ultrasound andCT-Scan in the diagnosis of non palpable testis.
CT Scan Finding in CVA Patients
Saeed Naghibi,Amirhossein Hashemi,Rahim Zojaji
Iranian Journal of Radiology , 2010,
Abstract: Background/Objective: Stroke is the most common cause of mortality and morbidity among neurological disorders. Multiple factors increase the risk of stroke. Some of these factors are modifiable (DM, HIN and smoking) and some are not (sex, age and race). Early diagnosis of stroke is very helpful in the prevention of serious complications of CVA of which CT scan imaging is a very helpful diagnostic tool. Evaluation of CT scan findings in CVA patients and association of these findings with related risk factors."nPatients and Methods: It is a descriptive and cross sectional study, which was performed during 2 years on 100 patients in 17 Shahrivar Hospital of Mashad. Patients were divided in two groups (ischemic and hemorrhagic) on the basis of CT scan and clinical findings. Also, we compared the prevalence of risk factors in the patients"nResults: The most common findings in CT scan imaging were brain infarction in 49 cases, atrophy in 42 cases and brain calcification in 41 cases. Internal capsule was the most common site of hemorrhage (39.15%). The most common site of infarction was temporal lobe (26.5%). The prevalence of hypertension in CVA patients with infarction findings was significantly higher than CVA patients without infarction findings (P=0.011). Also the prevalence of hypertension in the group with CT scan findings of hemorrhage was significantly higher than the group without CT scan findings of hemorrhage (p=0.031). Stroke in the female group was significantly higher than the male group and the commonest age was 70-79."nConclusion: CT scan is a useful imaging tool in diagnosis, evaluation of complications and the outcome of CVA patients."nKeywords: Cerebrovascular Accident, Stroke, Computed Tomography, Hypertension"n
Anatomical Variations of Neurovascular Structures Adjacent Sphenoid Sinus by using CT Scan  [PDF]
M. Davoodi,N. Saki,G. Saki,F. Rahim
Pakistan Journal of Biological Sciences , 2009,
Abstract: The aim of this research was to study of the relationship between anatomical variations of neurovascular structures adjacent sphenoid sinus with sex and position of appearance by using CT scan. In this retrospective study paranasal sinuses CT scan has been taken from 399 patients (210 male, 189 female) that referred to Imam Khomeini and Apadana Hospitals, Ahwaz, Iran. Furthermore, protrusion and dehiscence of Internal Carotid Artery (ICA), Maxillary Nerve (MN), Vidian Nerve (VN) and Optic Nerve (ON) into the sphenoid sinuses cavity have been investigated by using CT scan results. In 210 male patients the protrusion of interested variables were noticed as: ICA in 102 (48.5%) cases, ON in 80(38%) cases, MN in 74 (35.5%) cases, and VN in 60 (28.5%) cases, respectively. Also in 189 female patients group the protrusion of ICA, ON, MN, VN were noticed in 65 (34.3%), 66 (34.9%), 62 (32.8%) and 43 (22.7%) cases, respectively. The statistical analysis show significant difference (p = 0.001) of protrusion of ICA between male and female groups. In 210 male patients the dehiscence of ICA, ON, MN, VN were noticed in 82 (39%), 60 (28.5%), 60 (28.5%) and 66 (31.4%) cases, respectively. Also in 189 female patients the dehiscence of interested variables were noticed as: ICA in 85 (44.9 %), ON in 87 (46%), MN in 69 (36.5%), VN in 71 (37.5%) cases, respectively. The statistical analysis show significant difference (p = 0.03) of dehiscence of on variable in male and female groups. In order to increase the risk of intra-operative complications detailed preoperative investigation of neurovascular structures in sphenoid sinuses by use of CT scan images should be done properly.
Sinus CT scan and Functional Endoscopic Sinus
S. Naghibi,R. Zojaji,M. Khaki Hesari,A. H. Hashemi
Iranian Journal of Radiology , 2008,
Abstract: Background/Objective: Computerized tomography scan (CT scan) of the nose and paranasal sinuses plays a key role in preoperative evaluation of patients undergoing endoscope sinus surgery (ESS) for chronic sinusitis. The objective of this study was based on a comparative study among findings of nasal endoscopy during surgery and high resolution CT scan of the nose and paranasal sinuses, within the examinations for etiological"ninvestigation in chronic sinusitis, individualizing the importance of each exam for a conclusive diagnosis."nPatients and Methods: In this study during two years we prospectively compared the endoscopic findings during ESS with the findings of high resolution CT scan (Spiral CT scan, Philips model RX8000, dual slice, KV=140, MAS=450, pitch=1, thickness slice=3mm and thickness interval=5mm) in 51 patients with age ranging from 15 to 77 years who diagnosed as chronic sinusitis and had been selected for ESS."nResults: The most common co-morbidity found among our patients was allergy in 18 cases (35.3%). Hypertrophy of the inferior turbinate was the most"nobvious finding in the CT scan (70.6%) and also during endoscopic evaluation (68.6%). No significant relation was found between clinical symptoms and"ngender and the length of disease. Interestingly in eight unusual patients (choan atresia, bone wax in nasal cavity and six patients with small polyposis) the CT scan cannot show the problem."nConclusion: It seems that in unusual cases, the CT scan is not helpful (as you compare with the ESS findings), and it can miss many patients. The results of nasal fossa findings obtained by nasal endoscopy were more conclusive in the elucidation and diagnosis than those obtained by the CT scan of the paranasal sinuses.
Correlation Study between Skeletal Scintigraphy and CT Scan in Diagnosing Bone Metastases  [PDF]
Saeed Bafaraj, Ali Algamdi, Abdulaziz Almorjan
Open Journal of Medical Imaging (OJMI) , 2014, DOI: 10.4236/ojmi.2014.44025
Abstract: A retrospective study for 98 patient suspected to bone scan at department of radiology take place, to find out which imaging modality is more sensitive between computed tomography (CT) and bone scan; age group of patient was from 1 year to 90 year, the highest Site of Metastases for both Bone scan & CT was at vertebra with 31%, and the positive finding was also 31% for bone scan, while for CT the highest Site of Metastases was at forearm with 34%, and the sensitivity for CT was 44%, and 56% for bone scan. The study recommends that patients with bone metastases are kindly recommended to bone scan investigation rather than CT scan.
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