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FLUCTUATIONS IN DOSE LEVELS BASED ON PHANTOM LOCATION AND CBCT SCANNER SETTINGS
ABSTRACT
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Discussion: The use of CBCT allows for the evaluation of ICR characteristic features and eventually leads to better agreement on diagnosis, surgical treatment decision, and prognosis. References 1 Heithersay GS. Invasive cervical resorption. Endodontic Topics. 2004;7:73-92. 2 Heithersay GS. Clinical, radiologic, and histopathologic features of invasive cervical resorption. Quintessence Int. 1999;30:27-37. Conflict of Interest: None.
INCIDENTAL FINDINGS IN THE CERVICAL SPINE IN CBCT IMAGES. A.A. ALAMOUDI, F.M. JADU, A.M. JAN, H.H. MAWARDI, H.M. KHALIFAH. FACULTY OF DENTISTRY, KING ABDULAZIZ UNIVERSITY, JEDDAH, SAUDI ARABIA. Background: The cervical spine is an area commonly included in images of the oral and maxillofacial area. Therefore, oral and maxillofacial radiologists should be familiar with variations and abnormalities of this structure and should include any findings in their imaging reports. Objective: To examine the prevalence and nature of incidental findings in and around the cervical spine in cone beam computed tomography (CBCT) images. Material and Methods: A retrospective review of the CBCT cases was conducted at a university-based imaging center. Data on incidental findings in the cervical spine were collected. Other relevant data, such as patient age, gender, and dentate state, were also collected. Results: One hundred and ten cases were reported with incidental findings in the cervical spine out of 569, a prevalence of 19%. The most common finding was degenerative joint disease (DJD) (81%), which was often seen in females in their fourth decade of life. Discussion: The prevalence of cervical spine incidental findings is the current study is consistent with other published studies.1 However, the high incidence of DJD in a relatively young patient population is uncommon, and we believe it may be related to the high rate of motor vehicle accidents that are the primary cause of death in the region.2 Conclusions: This study confirms the relatively common occurrence of incidental findings in the cervical spines in CBCT examinations made for dental purposes and highlights the importance of recognizing and documenting these findings. References 1 Barghan S, Tahmasbi Arashlow M, Nair MK. Incidental findings on cone beam computed tomography studies outside of the maxillofacial skeleton. Int J Dent. 2016;2016:9196503. 2 Alsufyani NA. Cone beam computed tomography incidental findings of the cervical spine and clivus: retrospective analysis and review of the literature. Oral Surg Oral Med Oral Pathol Oral Radiol. 2017;123:e197-e217. Conflict of Interest: None.
FLUCTUATIONS IN DOSE LEVELS BASED ON PHANTOM LOCATION AND CBCT SCANNER SETTINGS. D. ALHAZMI, V. ALLAREDDY, G. AXT, S.A. ALLAREDDY, S.L. SOUSA
MELO. COLLEGE OF DENTISTRY, THE UNIVERSITY OF IOWA, IOWA CITY, IA. Background: Cone beam computed tomography (CBCT) has been widely used in dental imaging and became an essential imaging modality for many specialties, such as periodontology, oral surgery, oral diagnosis, orthodontics, and endodontics.1,2 It has been reported that CBCT involves a low amount of radiation exposure compared with multidetector computed tomography (MDCT); however, advanced CBCT units have a variety of scan settings that have to be considered with regard to patient exposure.3 Objectives: The aim of this study was to assess the dosimetry levels in a CBCT device (i-CAT FLX, Imaging Sciences, Hatfield, PA, USA) when operating on various scan protocols (e.g., voxel sizes and fields of view [FOV]). Materials and Methods: Exposure doses resulting from all combinations of scan protocols available on the CBCT machine were recorded with a Radcal MDH 1015, using a 10x53CT pencil ionization chamber and a 16-cm cylindrical polymethylmethacrylate phantom. Measurements performed on different field sizes and scan settings at different phantom locations were used in the study. The phantom was exposed 3 times at the same location to calculate a reliable measurement of the radiation by the ionization chamber. Doses were read by an oral and maxillofacial radiology resident. Two-way analysis of variance (ANOVA) and Tukey’s test were performed to identify any significant differences at an a-value of P = 0.05. Results: The dosimeter reading values increased as the size of FOV increased. The Quick scan+ protocol presented the least exposure among all scan protocols. There were no statistically significant differences among voxel sizes at the same scan settings. Discussion/Conclusions: The exposure doses from the studied scanner are substantially dependent on the selected scan protocol and location within the phantom. The reduction of the dose with acceptable clinical image quality should be obtained by a proper selection of the scan settings in the CBCT machine. References 1 Hofmann E, Schmid M, Sedlmair M, Banckwitz R, Hirschfelder U, Lell M. Comparative study of image quality and radiation dose of cone beam and low-dose multislice computed tomography-an in-vitro investigation. Clin Oral Investig. 2014;18:301-311. 2 Ludlow JB, Davies-Ludlow LE, Brooks SL, Howerton WB. Dosimetry of 3 CBCT devices for oral and maxillofacial radiology: CB Mercuray, NewTom 3G and i-CAT. Dentomaxillofac Radiol. 2006;35:219-226. 3 Ludlow J B, Ivanovic M. Comparative dosimetry of dental CBCT devices and 64-slice CT for oral and maxillofacial radiology. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2008;106:106-114. Conflict of Interest: None.
MUCUS EXTRAVASATION PHENOMENON HIDING A MUCOEPIDERMOID CARCINOMA IN THE FLOOR OF MOUTH. D. ALHAZMI, S.M. STEWARD-THARP, V. ALLAREDDY, S. ANAMALI-ALLAREDDY, S.L. SOUSA MELO. COLLAGE OF DENTISTRY, THE UNIVERSITY OF IOWA, IOWA CITY, IA.
OOOO January 2019
e32
Discussion: The use of CBCT allows for the evaluation of ICR characteristic features and eventually leads to better agreement on diagnosis, surgical treatment decision, and prognosis. References 1 Heithersay GS. Invasive cervical resorption. Endodontic Topics. 2004;7:73-92. 2 Heithersay GS. Clinical, radiologic, and histopathologic features of invasive cervical resorption. Quintessence Int. 1999;30:27-37. Conflict of Interest: None.
INCIDENTAL FINDINGS IN THE CERVICAL SPINE IN CBCT IMAGES. A.A. ALAMOUDI, F.M. JADU, A.M. JAN, H.H. MAWARDI, H.M. KHALIFAH. FACULTY OF DENTISTRY, KING ABDULAZIZ UNIVERSITY, JEDDAH, SAUDI ARABIA. Background: The cervical spine is an area commonly included in images of the oral and maxillofacial area. Therefore, oral and maxillofacial radiologists should be familiar with variations and abnormalities of this structure and should include any findings in their imaging reports. Objective: To examine the prevalence and nature of incidental findings in and around the cervical spine in cone beam computed tomography (CBCT) images. Material and Methods: A retrospective review of the CBCT cases was conducted at a university-based imaging center. Data on incidental findings in the cervical spine were collected. Other relevant data, such as patient age, gender, and dentate state, were also collected. Results: One hundred and ten cases were reported with incidental findings in the cervical spine out of 569, a prevalence of 19%. The most common finding was degenerative joint disease (DJD) (81%), which was often seen in females in their fourth decade of life. Discussion: The prevalence of cervical spine incidental findings is the current study is consistent with other published studies.1 However, the high incidence of DJD in a relatively young patient population is uncommon, and we believe it may be related to the high rate of motor vehicle accidents that are the primary cause of death in the region.2 Conclusions: This study confirms the relatively common occurrence of incidental findings in the cervical spines in CBCT examinations made for dental purposes and highlights the importance of recognizing and documenting these findings. References 1 Barghan S, Tahmasbi Arashlow M, Nair MK. Incidental findings on cone beam computed tomography studies outside of the maxillofacial skeleton. Int J Dent. 2016;2016:9196503. 2 Alsufyani NA. Cone beam computed tomography incidental findings of the cervical spine and clivus: retrospective analysis and review of the literature. Oral Surg Oral Med Oral Pathol Oral Radiol. 2017;123:e197-e217. Conflict of Interest: None.
FLUCTUATIONS IN DOSE LEVELS BASED ON PHANTOM LOCATION AND CBCT SCANNER SETTINGS. D. ALHAZMI, V. ALLAREDDY, G. AXT, S.A. ALLAREDDY, S.L. SOUSA
MELO. COLLEGE OF DENTISTRY, THE UNIVERSITY OF IOWA, IOWA CITY, IA. Background: Cone beam computed tomography (CBCT) has been widely used in dental imaging and became an essential imaging modality for many specialties, such as periodontology, oral surgery, oral diagnosis, orthodontics, and endodontics.1,2 It has been reported that CBCT involves a low amount of radiation exposure compared with multidetector computed tomography (MDCT); however, advanced CBCT units have a variety of scan settings that have to be considered with regard to patient exposure.3 Objectives: The aim of this study was to assess the dosimetry levels in a CBCT device (i-CAT FLX, Imaging Sciences, Hatfield, PA, USA) when operating on various scan protocols (e.g., voxel sizes and fields of view [FOV]). Materials and Methods: Exposure doses resulting from all combinations of scan protocols available on the CBCT machine were recorded with a Radcal MDH 1015, using a 10x53CT pencil ionization chamber and a 16-cm cylindrical polymethylmethacrylate phantom. Measurements performed on different field sizes and scan settings at different phantom locations were used in the study. The phantom was exposed 3 times at the same location to calculate a reliable measurement of the radiation by the ionization chamber. Doses were read by an oral and maxillofacial radiology resident. Two-way analysis of variance (ANOVA) and Tukey’s test were performed to identify any significant differences at an a-value of P = 0.05. Results: The dosimeter reading values increased as the size of FOV increased. The Quick scan+ protocol presented the least exposure among all scan protocols. There were no statistically significant differences among voxel sizes at the same scan settings. Discussion/Conclusions: The exposure doses from the studied scanner are substantially dependent on the selected scan protocol and location within the phantom. The reduction of the dose with acceptable clinical image quality should be obtained by a proper selection of the scan settings in the CBCT machine. References 1 Hofmann E, Schmid M, Sedlmair M, Banckwitz R, Hirschfelder U, Lell M. Comparative study of image quality and radiation dose of cone beam and low-dose multislice computed tomography-an in-vitro investigation. Clin Oral Investig. 2014;18:301-311. 2 Ludlow JB, Davies-Ludlow LE, Brooks SL, Howerton WB. Dosimetry of 3 CBCT devices for oral and maxillofacial radiology: CB Mercuray, NewTom 3G and i-CAT. Dentomaxillofac Radiol. 2006;35:219-226. 3 Ludlow J B, Ivanovic M. Comparative dosimetry of dental CBCT devices and 64-slice CT for oral and maxillofacial radiology. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2008;106:106-114. Conflict of Interest: None.
MUCUS EXTRAVASATION PHENOMENON HIDING A MUCOEPIDERMOID CARCINOMA IN THE FLOOR OF MOUTH. D. ALHAZMI, S.M. STEWARD-THARP, V. ALLAREDDY, S. ANAMALI-ALLAREDDY, S.L. SOUSA MELO. COLLAGE OF DENTISTRY, THE UNIVERSITY OF IOWA, IOWA CITY, IA.