Head Protocol Research Articles

Electroacupuncture Protocol for Sensory and Motor Function Recovery After Orthognathic Surgery: a Randomized Clinical Trial.

Orthognathic surgery is utilized to rectify facial deformities, but it can lead to neurosensory alterations. Electroacupuncture has been shown to enhance sensitivity and motor functions in patients post-surgery. However, its application in traumatic facial injuries remains inadequately researched. To investigate the effects of electroacupuncture on sensitivity and orofacial function in patients undergoing orthognathic surgery. A randomized clinical trial involving patients undergoing bimaxillary orthognathic surgery and genioplasty who are randomly allocated to either a physiotherapy (PT) or physiotherapy plus electroacupuncture group (PTEA). Participants will be allocated to their respective therapies for a duration of six weeks. The PT group will receive a 50-minute physical therapy session along with 30 minutes of simulated procedure. The PTEA group will receive 50 minutes of physical therapy followed by 30 minutes of electroacupuncture. Before treatment, sensitivity will be assessed using the SMILE Sensitivity Test-BAURU kit, edema will be evaluated using the MD Anderson Cancer Center Head and Neck Lymphedema protocol, range of motion will be measured using a digital caliper, and muscle pain and fatigue will be gauged using numerical scales. The chewing function will be evaluated using the Chewing Quality Assessment Questionnaire. All assessments will be repeated at three and six months following the initiation of treatment. This study may provide reliable and high-quality clinical evidence regarding the impact of electroacupuncture on restoring altered sensation and motor function in patients undergoing orthognathic surgery.

Image quality of virtual monochromatic and material density iodine images for evaluation of head and neck neoplasms using deep learning-based CT image reconstruction – A retrospective observational study

PurposeTo compare the quality of deep learning image reconstructed (DLIR) virtual monochromatic images (VMI) and material density (MD) iodine images from dual-energy computed tomography (DECT) for the evaluation of head and neck neoplasms with CT scans from a conventional single-energy protocol. MethodA total of 294 head and neck CT scans (98 VMIs operated at 60 keV, 102 MD iodine images, and 94 images from a 120 kVp single-energy CT (SECT) protocol) were retrospectively evaluated. VMIs and MD iodine images were generated using the Gemstone Spectral Imaging (GSI) mode using DLIR and metal artifact reduction (MAR) algorithms. SECT images were generated using adaptive statistical iterative reconstruction (ASIR-V). Images were scored by two independent readers on a 6-point Likert-type scale for overall image quality, vessel contrast, soft tissue contrast, noise texture, noise intensity, artifact reduction, and sharpness. ResultsSubjective overall image quality was rated as superior or excellent in 98 % of DLIR-based MD iodine images and VMIs, but only in 55 % of ASIR-V-based SECT images. For each individual quality criterion, image quality of VMIs and MD iodine images was rated as better than that of SECT images (p < 0.001 in each case). Noise texture and intensity were rated better in MD iodine images than in VMIs. ConclusionDECT using both DLIR and MAR for the generation of VMIs and MD iodine images resulted in higher subjective quality of oncologic head and neck images than ASIR-V-based SECT. Noise reduction and noise texture were best achieved with DLIR-based MD iodine images.

Artefacts on magnetic resonance imaging with Osia®2 bone conduction hearing aid: A cadaver study

Objectives: Hearing implants often limit the assessment of magnetic resonance examinations due to susceptibility artefacts. Our aim was to evaluate the impact of artefacts attributed to the Osia®2 implant system in terms of utility in visualizing selected cranial structures. Methods: A BI300 implant and an OSI200 actuator were implanted into a human cadaver head in the audiologically most favourable position according to the manufacturer’s guidelines. Scanning was accomplished using the institutional head and inner ear protocol with a General Electric 1.5 Tesla scanner with retained and removed implant magnet, extended with T1 and T2 weighted sequences with metal-artefact reduction (MAVRIC SL). Image quality was evaluated by three radiologists. Results: The Osia®2 produced significant artefacts in most of the series of standard imaging sequences predominantly on the ipsilateral side of the head. The majority of the artefacts were caused by the implant magnet. Even without removing the magnet, MAVRIC SL improved image quality to such an extent that it became comparable with that after magnet removal. Conclusions: The standard sequences suffer considerable quality loss due to the artefacts, attributed predominantly to the magnetic component. Metal-artefact reduction sequences are effective in obtaining sufficient-to-good quality images without surgical magnet removal.

Comparison of Diffusion-weighted MRI using Singe-Shot Echo-planar Imaging (SS-EPI) and Split Acquisition of Fast Spin Echo Signal (SPLICE) Imaging, a non-EPI technique, in Tumors of the Head and Neck.

Diffusion-weighted imaging (DWI) using single-shot echo planar imaging (DW-EPI) is susceptible to distortions around air-filled cavities and dental fillings, typical for the head and neck area. Non-EPI, Split acquisition of fast spin echo signals for diffusion imaging (DWSPLICE) could reduce these distortions and enhance image quality, thereby potentially improving recurrence assessment in squamous cell carcinoma (SCC) of the head and neck region. This study evaluated whether DW-SPLICE is a viable alternative to DW-EPI through quantitative and qualitative analyses. The DW-SPLICE sequence was incorporated into the standard 3.0T head and neck MRI protocol with DW-EPI. Retrospective analysis was conducted on two subgroups: firstly benign or malignant lesions, and secondly post-treatment SCC recurrence. In both subgroups Image quality and distortion were scored by two independent radiologists, blinded for DW-technique, and evaluated using mixed-effect linear models. Lesion apparent diffusion coefficient (ADC) values were assessed with inter-class correlation (ICC) and Bland-Altman analyses. DWI's delineation geometric similarity to T1-weighted post-contrast (T1Wc) MRI was evaluated using the Dice Similarity Coefficient (DSC) before and after registration. Recurrence in post-treatment SCC scans was evaluated by the same two radiologists blinded for DW-technique. Recurrence detection rates were then compared between DW-SPLICE and DW-EPI using mixed logistic regression at six months and at one-year post-scan follow-up data. From August 2020 to January 2022, 55 benign or malignant lesion scans (55 patients) and 74 post-treatment SCC scans (66 patients) were analyzed. DW-SPLICE scored better on image quality and showed less overall distortion than DW-EPI (0.04<p<0.001). There was high ADC measurement reliability (ICC=0.93, p<0.001), though a proportional bias was also observed (β=0.11, p=0.03), indicating the bias increases as ADC values rise. DWSPLICE exhibited greater geometric similarity to T1Wc before registration (DSC 0.63 vs 0.47, p<0.001) and outperformed DW-EPI by more accurately identifying recurrences after one year (OR=0.96, p=0.05) but not after six months (OR=0.72, p=0.13). DW-SPLICE surpasses DW-EPI on image distortion and quality and improves diagnostic reliability for detecting recurrent or residual SCC on 3T MRI of the HN. Consistent use of one method for follow-up is advised, as ADC values are not completely interchangeable. Integrating DW-SPLICE can significantly improve tumor assessments in clinical practice. ANTs = Advanced Normalization Tools; DSC = Dice Similarity Coefficient; DW-EPI = Diffusion-weighted single-shot echo planar imaging; DW-MS-EPI = Diffusion-weighted multi-shot echo planar imaging; DW-SPLICE = Diffusion-weighted split acquisition of fast spin echo signals for diffusion imaging; DW-TSE = Diffusion-weighted Turbo Spin Echo; ICC = Intraclass Correlation Coefficient; ROC = Receiver Operating Characteristic; SCC = Squamous cell carcinoma; T1WIc = T1 weighted imaging with gadolinium contrast.

Characterization of kilovoltage x-ray image guidance system with a novel post-processing algorithm on a new slip ring-mounted radiotherapy system.

This study evaluates the performance of a kilovoltage x-ray image-guidance system equipped with a novel post-processing optimization algorithm on the newly introduced TAICHI linear accelerator (Linac). A comparative study involving image quality tests and radiation dose measurements was conducted across six scanning protocols of the kV-cone beam computed tomography (CBCT) system on the TAICHI Linac. The performance assessment utilized the conventional Feldkamp-Davis-Kress (FDK) algorithm and a novel Non-Local Means denoising and adaptive scattering correction (NLM-ASC) algorithm. Image quality metrics, including spatial resolution, contrast-to-noise ratio (CNR), and signal-to-noise ratio (SNR), were evaluated using a Catphan 604 phantom. Radiation doses for low-dose and standard protocols were measured using a computed tomography dose index (CTDI) phantom, with comparative measurements from the Halcyon Linac's iterative CBCT (iCBCT). The NLM-ASC algorithm significantly improved image quality, achieving a 300%-1000% increase in CNR and SNR over the FDK-only images and it also showed a 100%-200% improvement over the iCBCT images from Halcyon's head protocol. The optimized low-dose protocols yielded higher image quality than the standard FDK protocols, indicating potential for reduced radiation exposure. Clinical implementation confirmed the TAICHI system's utility for precise and adaptive radiotherapy. The kV-IGRT system on the TAICHI Linac, with its novel post-processing algorithm, demonstrated superior image quality suitable for routine clinical use, effectively reducing image noise without compromising other quality metrics.

Evaluation of imaging dose for the cone beam computed tomography system of the ring-shaped radiotherapy unit using the different International Electrotechnical Commission approaches

PurposeDaily imaging is mandatory for the Halcyon and Ethos, which are the new ring-shaped radiotherapy units. This study quantified the imaging dose of the cone beam computed tomography (CBCT) system of the new ring-shaped radiotherapy units using the latest International Electrotechnical Commission (IEC) measurement approach. Furthermore, we investigated the influence of collimation width on the imaging dose and compared the imaging dose values obtained using three IEC measurement approaches. MethodsThe IEC has proposed three approaches for measuring CTDI100: traditional, transition, and the latest measurement approach. In addition to the dose measured on the CTDI phantom, the latest IEC approach uses correction factors measured in free air for CTDI100 measurement. The imaging dose was measured for all scanning protocols using the latest IEC approach. To investigate the influence of the collimation width on the imaging dose, the associated dose metric values were evaluated and compared using different IEC approaches to increase the collimation width (2–28 cm). Furthermore, the imaging system output stability was evaluated by repeated measurements. ResultsIn the repeated measurements, the standard deviation of CTDIw value for the pelvis and head protocol was 0.05 mGy and 0.01 mGy, respectively. And the coefficient of variation was 0.21% and 0.23%, respectively. The measured CTDIw values of the clinical protocols were higher than the vendor-provided value, except for the pelvis protocol. The value of CTDIw changes little with increasing collimation width using the latest IEC approach. The traditional and transition approaches either underestimated or overestimated the value of CTDIw, as measured by the latest IEC approach, with increasing collimation width. ConclusionsThe new ring-shaped radiotherapy units imaging system has good output stability. The CTDIw values measured for clinical scanning protocols generally exceeded the vendor-provided values. Compared with the latest IEC CTDI100 measurement approach, the traditional and transition measurement approaches were more influenced by beam width. For wide CBCT scans, rationalizing the choice of imaging dose measurement approach is important.

MRI Brain In Case Non-Hemmoragic STROKE At Gatot Soebroto Army Central Hospital (RSPAD)

Non-hemorrhagic stroke caused by thrombus and embolism, occurs due to decreased blood flow to certain places in the brain through the process of stenosis. Identification of the pathophysiology of non-hemorrhagic stroke due to stenosis is important in patient management, especially in providing appropriate therapy. Cerebral lesions visualized on MRI show tissue damage due to reduced blood flow to the brain, which deprives brain cells of oxygen and essential nutrients. The research was carried out from 03 to 29 October 2022 at Gatot Soebroto Army Hospital, with 1 sample analysis of a 70-year-old man with complaints of partial paralysis of the left side of the body covering the arms and legs, the study was carried out using descriptive qualitative methods with a case study approach. The results of MRI Brain imaging using a complete Head Protocol consisting of sequences T1, T2, FLAIR, DWI, ASL 3d_Tra_Iso, TOF MRA, MRV and Carotis, and SWI showed acute infarction, multiple lacunar infarction, cerebral atrophy, hypoperfusion. Conclusion: MRI examination of the head using a complete head protocol at Gatot Soebroto Hospital is very effective for assessing non-hemorrhagic stroke.

Feasibility of individualized home exercise programs for patients with head and neck cancer-study protocol and first results of a multicentre single-arm intervention trial (OSHO #94).

Patients with head and neck cancer (PwHNC) benefit from targeted exercise interventions: symptom relief, compensation for dysfunction, improvement in quality of life (QoL). Data on acceptance physical interventions in PwHNC are rare. The 'OSHO #94' trial investigates the short- and medium-term effects of individualized home exercise in PwHNC on QoL, physical activity and functionality. The study includes a feasibility phase (proof of concept) in order to evaluate the acceptance. Here we present the study protocol as well as the feasibility results. This prospective, multicentre, single-arm intervention study includes PwHNC ≥18 years of age in aftercare or palliative care with stable remission under immunotherapy. The study opened in January 01, 2021, with estimated completion by December 31, 2024. The PwHNC receive an individualized home exercise program consisting of mobilization, coordination, strengthening and stretching exercises. This should be carried out at least three times a week over 12 weeks for 15 to 30 minutes, supplemented by aerobic training two to three times a week for 30 minutes (intervention). Once weekly telephone calls with a physiotherapist are performed. Subsequently, there is a 12-week follow-up (FU) without exercise specifications/contact. Outcomes are measured before and after the intervention and following the FU. Primary outcome of the feasibility phase (n = 25) was the determination of the dropout rate during the intervention with a termination cut off if more than 30% PwHNC withdrew premature. The primary outcome of the OSHO #94' trial (N = 53) is the change in global QoL score from pre- to post-intervention (EORTC QLQ-C30). Secondary outcomes include clinical and patient-reported measures, training details as well as functional diagnostic data (e.g. level of physical activity, training frequency, flexibility, fall risk and aerobic performance). 25 PwHNC were enrolled onto the feasibility cohort. Only16% (4/25 patients) did not complete the study. Therefore, recruitment of PwHNC was continued. The dropout rate was adjusted from 30% (N = 60) to 20% (N = 53, calculated sample size n = 42 PwHNC and 20% (n = 11) to dropout). Individualized home exercise programs in PwHNC in aftercare seem feasible. Consequently, the aim is now to evaluate the short and medium-term effects of individualized home exercise.

THE INFLUENCE OF COORDINATION AND JOB DESCRIPTION ON WORK PRODUCTIVITY THROUGH WORK DISCIPLINE OF REGIONAL HEAD PROTOCOLARY EMPLOYEES IN THE PROTOCOL AND COMMUNICATION SECTION OF BONDOWOSO REGIONAL SECRETARIAT LEADERS

Measuring the work productivity of Regional Head Protocol employees in the Protocol and Communication Section of the Bondowoso Regency Regional Secretariat Leadership is an important concern in the context of optimizing the implementation of protocol events and public services. The aim of this research is to determine and analyze the influence of coordination and job descriptions on work productivity through the work discipline of Regional Head Protocol employees in the Protocol and Communication Section of the Bondowoso Regency Regional Secretariat Leadership. The population and sample in this research were 50 employees, so the sampling technique used was saturated sampling or census. The research method used in this research is descriptive and verification methods. The data analysis technique used in this research is path analysis with the help of the SPSS application. The test results prove that coordination and job descriptions have a significant effect on work discipline and the work productivity of employees in the Protocol and Communication Section of the Regional Secretariat of Bondowoso Regency. Work discipline is able to provide a mediating effect between coordination and job description on work productivity. Keywords: coordination, job description, work discipline and productivity. Keywords: coordination, job description, work discipline and productivity

Computed tomography system performance for different iterative reconstruction algorithms

The number of the Computed Tomography (CT) examinations has increased greatly over the past decade; This has made CT doses the largest source of the individual effective dose from medical exposures worldwide. Evaluation of image quality in CT is an important issue to ensure diagnostic accuracy, while keeping the radiation dose especially to the pediatric patient as low as reasonably possible. The purpose of this study was to assess the physical and psychophysical image quality in pediatric CT for different iterative reconstruction (IR) algorithms. The image quality was measured on each CT system using pediatric QRM abdomen and thorax phantoms for clinical thorax and abdomen examination scanning parameters and using the Catphan 600 phantom for head examination scanning parameters. The performance of each CT systems was evaluated individually using conventional filtered back-projection (FBP) and IR algorithm employed in that system. Noise, contrast-to-noise ratio (CNR), inverse image quality figure (IQFinv), modulation transfer function (MTF) and noise power spectrum (NPS) were assessed for FBP and wide range of iteration level of different IR algorithms. Figure of Merit (FOM) parameter was calculated to characterize the dose efficiency of each CT system. The CTDIvol values were changed from 20.6 to 45.7, 0.9 to 7.4 and 2.4–9.6 mGy for pediatric head, thorax and abdomen scanning protocols between CT systems, respectively. With increasing iteration level, image noise decreased while CNR and IQFinv increased. NPS peak was decreased with increasing iteration level for both two (2D) and three dimensional (3D) NPS and the ratio of the 3D NPS to 2D NPS varied from 4.5 to 8.3 for pediatric head, from 4.6 to 8.7 for pediatric thorax and from 4.0 to 14.0 for pediatric abdomen scanning protocols. For all IR algorithms employed with CT systems used in this study, the FOM values were increased with increasing iteration level.

ACR benchmark testing of a novel high-speed ring-gantry linac kV-CBCT system.

A new generation cone-beam computed tomography (CBCT) system with new hardware design and advanced image reconstruction algorithms is available for radiation treatment simulation or adaptive radiotherapy (HyperSight CBCT imaging solution, Varian Medical Systems-a Siemens Healthineers company). This study assesses the CBCT image quality metrics using the criteria routinely used for diagnostic CT scanner accreditation as a first step towards the future use of HyperSight CBCT images for treatment planning and target/organ delineations. Image performance was evaluated using American College of Radiology (ACR) Program accreditation phantom tests for diagnostic computed tomography systems (CTs) and compared HyperSight images with a standard treatment planning diagnostic CT scanner (Siemens SOMATOM Edge) and with existing CBCT systems (Varian TrueBeam version 2.7 and Varian Halcyon version 2.0). Image quality performance for all Varian HyperSight CBCT vendor-provided imaging protocols were assessed using ACR head and body ring CT phantoms, then compared to existing imaging modalities. Image quality analysis metrics included contrast-to-noise (CNR), spatial resolution, Hounsfield number (HU) accuracy, image scaling, and uniformity. All image quality assessments were made following the recommendations and passing criteria provided by the ACR. The Varian HyperSight CBCT imaging system demonstrated excellent image quality, with the majority of vendor-provided imaging protocols capable of passing all ACR CT accreditation standards. Nearly all (8/11) vendor-provided protocols passed ACR criteria using the ACR head phantom, with the Abdomen Large, Pelvis Large, and H&N vendor-provided protocols produced HU uniformity values slightly exceeding passing criteria but remained within the allowable minor deviation levels (5-7 HU maximum differences). Compared to other existing CT and CBCT imaging modalities, both HyperSight Head and Pelvis imaging protocols matched the performance of the SOMATOM CT scanner, and both the HyperSight and SOMATOM CT substantially surpassed the performance of the Halcyon 2.0 and TrueBeam version 2.7 systems. Varian HyperSight CBCT imaging system could pass almost all tests for all vendor-provided protocols using ACR accreditation criteria, with image quality similar to those produced by diagnostic CT scanners and significantly better than existing linac-based CBCT imaging systems.

Introducing fitting models for estimating age-specific dose and effective dose in paediatric patients undergoing head, chest and abdomen-pelvis imaging protocols: a patient study.

Concerns regarding the adverse consequences of radiation have increased due to the expanded application of computed tomography (CT) in medical practice. Certain studies have indicated that the radiation dosage depends on the anatomical region, the imaging technique employed and patient-specific variables. The aim of this study is to present fitting models for the estimation of age-specific dose estimates (ASDE), in the same direction of size-specific dose estimates, and effective doses based on patient age, gender and the type of CT examination used in paediatric head, chest and abdomen-pelvis imaging. A total of 583 paediatric patients were included in the study. Radiometric data were gathered from DICOM files. The patients were categorised into five distinct groups (under 15 years of age), and the effective dose, organ dose and ASDE were computed for the CT examinations involving the head, chest and abdomen-pelvis. Finally, the best fitting models were presented for estimation of ASDE and effective doses based on patient age, gender and the type of examination. The ASDE in head, chest, and abdomen-pelvis CT examinations increases with increasing age. As age increases, the effective dose in head and abdomen-pelvis CT scans decreased. However, for chest scans, the effective dose initially showed a decreasing trend until the first year of life; after that, it increases in correlation with age. Based on the presented fitting model for the ASDE, these CT scan quantities depend on factors such as patient age and the type of CT examination. For the effective dose, the gender was also included in the fitting model. By utilising the information about the scan type, region and age, it becomes feasible to estimate the ASDE and effective dose using the models provided in this study.

The Journey to Improve the College of American Pathologists Cancer Biomarker Reporting Protocols.

Biomarker reporting has increasingly become a key component of pathology reporting, providing diagnostic, prognostic, and actionable therapeutic data for patient care. To expand and improve the College of American Pathologists (CAP) biomarker protocols. We surveyed CAP members to better understand the limitations they experienced when reporting cancer biomarker results. A Biomarker Workgroup reviewed the survey results and developed a strategy to improve and standardize biomarker reporting. Drafts of new and revised biomarker protocols were reviewed in both print and electronic template formats during interactive webinars presented to the CAP House of Delegates. Feedback was collected, and appropriate revisions were made to finalize the protocols. The first phase of the CAP Biomarker Workgroup saw the development of (1) a new stand-alone general Immunohistochemistry Biomarker Protocol that includes reporting for ER (estrogen receptor), PR (progesterone receptor), Ki-67, HER2 (human epidermal growth factor receptor 2), PD-L1 (programmed death ligand-1), and mismatch repair; (2) a new Head and Neck Biomarker Protocol that updates the prior 2017 paper-only version into an electronic template, adding new diagnostic and theranostic markers; (3) a major revision to the Lung Biomarker Protocol to streamline it and add in pan-cancer markers; and (4) a revision to the Colon and Rectum Biomarker Protocol to add HER2 reporting. We have taken a multipronged approach to improving biomarker reporting in the CAP cancer protocols. We continue to review current biomarker reporting protocols to reduce and eliminate unnecessary methodologic details and update with new markers as needed. The biomarker templates will serve as standardized modular units that can be inserted into cancer-reporting protocols.

PENGARUH PARAMETER CT UNTUK OPTIMISASI DOSIS RADIASI DAN KUALITAS CITRA CT SCAN PADA PEMERIKSAAN KEPALA DAN ABDOMEN DI RS SENTRA MEDIKA CIBINONG

Radiation dose optimization in head and abdomen examinations is an effort to ensure safety and minimize the risks of exposure to CT Scan radiation. Therefore, various efforts are necessary to reduce radiation doses. This study aims to obtain an optimal radiation dose while maintaining image quality. The optimization efforts were carried out by the radiology team at RS Sentra Medika Cibinong using the CT Scan GE OPTIMA 660. The method involved scanning head and abdomen phantoms using optimization factors (Noise Index, Slice Thickness, Pitch, and Rotation Time) and then analyzing the images for noise uniformity, MTF (Modulation Transfer Function), and NPS (Noise Power Spectrum) while recording radiation dose in terms of CTDIvol and DLP. Based on the research data using GE standard Head protocol and respective optimizations, the radiation dose values obtained were CTDIVol = 68 mGy; DLP = 2042 mGy.cm and CTDIVol = 48 mGy; DLP = 1662 mGy.cm. Furthermore, the image quality produced by the GE standard Head protocol and respective optimizations resulted in MTF values of 0.55 (1/mm) and 0.91 (1/mm), noise uniformity of 0.6 HU and 1.6 HU, and NPS deviation of 8.7%. Regarding the Abdomen protocol, using GE standard and respective optimizations, the radiation dose values obtained were CTDIVol = 32 mGy; DLP = 1025 mGy.cm and CTDIVol = 22 mGy; DLP = 955 mGy.cm. Additionally, the image quality produced by the GE standard Abdomen protocol and respective optimizations resulted in MTF values of 0.58 (1/mm) and 0.6 (1/mm), noise uniformity of 0.6 HU and 1.6 HU, and NPS deviation of 7.6%. Thus, the protocols using optimization factors were proven to reduce radiation dose by approximately 41.6-45.4% while maintaining image quality compared to the GE standard protocol, which focuses more on improving image quality rather than optimizing the radiation dose received by patients. Keywords: CT Scan, Optimization Factors, Image Quality, CTDIvol, DLP.

Analisis Multi Slice Computed Tomography (MSCT) Nasofaring Dengan Klinis Karsinoma Nasofaring Di Instalasi Radiodiagnostik RSUP Dr. Hasan Sadikin Bandung

Background: Nasopharyngeal carcinoma is cancer that occurs in the nasopharyngeal mucosa which shows squamous cell differentiation. MSCT has become a reliable imaging technique for assessing the extent of nasopharyngeal carcinoma. Nasopharyngeal MSCT examination procedure with clinical nasopharyngeal carcinoma at the Radiodiagnostic Installation of Dr. RSUP. Hasan Sadikin Bandung uses a head protocol and slice thickness of 3-5 mm. This study aims to determine the Nasopharyngeal MSCT examination procedure for clinical nasopharyngeal carcinoma using a head protocol with manual intravenous contrast injection.&#x0D; Method: The type of research used is descriptive qualitative research with a case study approach. This research was conducted at the Radiodiagnostic Installation of RSUP Dr. Hasan Sadikin Bandung The subjects in this study consisted of three patients, two radiographers and three radiologists. Data collection methods are carried out through observation, interviews and documentation. The data analysis technique used is an interactive analysis model.

Accuracy of Electron Density Mapping of a Novel kVCBCT System Designed for Planning

A recently developed advanced kVCBCT system, designed for simulation and planning, includes improvements to the imaging panel and reconstruction technique, enabling more accurate electron density mapping than a typical CBCT. This study investigates the accuracy, limitations, and dosimetric impact of this new system. CBCT images were taken of both large (pelvis) and small (head) electron density phantoms with inserts ranging from lung (0.29) to cortical bone (1.69). Images were taken with several pre-set protocols with energies of 125 kVp and 140 kVp. The effects of longitudinal buildup (for scatter due to the cone-beam geometry) and blade position were also investigated. The HU values of each insert were measured over a small region of interest. Several electron density curves were generated - pelvis protocol on the large phantom, head protocol on the small phantom, and average - and imported into a treatment planning system. Dose calculation was performed using each curve and differences were observed. HU to electron density mapping was sensitive to the use of longitudinal buildup and blade position, with differences in the curves observed at both low and high electron densities, due to imager saturation effects not found in typical clinical scenarios. Subsequent studies used both longitudinal buildup and fully opened blades. Under these conditions, mapping was not sensitive to technique or phantom size at low electron densities. At higher values, the curves diverged, with the head protocol showing higher HU values and the pelvis protocol showing lower. The average curve matched very closely with the curve from our standard CT simulator. Dose calculation showed little dependence on the curve chosen, with max point dose differences of 1.2% between the pelvis and average scans, though most of the plan was <0.5% different. Results for the head protocol were similar. The system provides reliable HU values comparable to a CT simulator, though it is important to consider the effects of imager saturation by choosing appropriate scatter and collimation. The calibration is slightly sensitive to the choice of phantom size and beam energy, though these differences led to negligible (<0.5%) differences in dose calculation accuracy.

ACR Accreditation of a Novel Linac-Based kV-CBCT System on a High-Speed Ring-Gantry

An advanced kV-CBCT imaging system mounted on a high-speed ring-gantry Linac has recently been introduced, offering improved imaging hardware and reconstruction software to produce high quality CBCT images usable for treatment planning. Imaging performance of the system was assessed using the American College of Radiology (ACR) accreditation designed for diagnostic CT systems, additionally comparing its results to pre-existing diagnostic CT and Linac-based CBCT systems. All imaging protocols on the novel imaging system were scanned with the ACR head phantom and evaluated using ACR recommended testing and passing criteria. ACR image quality parameters include contrast-to-noise ratio (CNR), spatial resolution, HU accuracy, image scaling, and HU uniformity. CNR ≥1.0 for adult head and body, ≥0.7 for pediatric head, and ≥0.4 for pediatric body imaging protocols pass ACR criteria. Spatial resolution ≥6 line-pairs/cm for head and ≥5 line-pairs/cm for body protocols pass ACR criteria. HU accuracy passing criteria includes acrylic (110 to 135 HU), air (-1005 to -970 HU), bone (850 to 970 HU), polyethylene (-107 to -84 HU), and water (-7 to 7 HU). Image scaling measurements with errors ≤5% and HU uniformity maximum differences ≤5 HU pass ACR criteria. For machine cross-comparisons, adult Head and Pelvis imaging protocols were acquired on an existing diagnostic CT and 2 Linac-based CBCT systems (1 traditional C-arm and 1 ring-gantry) and analyzed with the same ACR methodology and passing criteria, with passing rates compared. On the novel imaging system, all standard patient size imaging protocols using 125 kVp (Head, H&N, Thorax, Thorax Slow, Breast, Abdomen, Pelvis, Pediatric Head, and Pediatric Abdomen) passed all ACR criteria; while 2 larger patient focused imaging protocols using 140 kVp (Abdomen Large and Pelvis Large) produced minor deviations on HU uniformity (maximum differences of 5 - 7 HU) but passed all other ACR criteria. The novel system matched passing rates of a diagnostic CT simulator, and outperformed pre-existing Linac based CBCT imaging systems. This newly developed advanced imaging system produces high quality images, meeting diagnostic CT ACR recommendations and far surpassing the CBCT image quality currently available on pre-existing Linacs.

Head and neck exam practices of dental professionals.

Periodic examination of the head and neck includes screening for oral cancer, which is largely performed in dental offices by vigilant oral healthcare providers. The aim of this study was to assess practice patterns among Virginia dentists in performing head and neck exams and the referral rates of biopsies after completion of head and neck exams. We hypothesized that not all dentists perform head and neck exams and there is a difference between dentists who refer patients for a biopsy and those that perform biopsies. General dentists and dental specialists who are members of the Virginia Dental Association were invited to participate in a cross-sectional survey study through REDCap to self-report their head and neck exam protocols. A total of 224 providers completed the survey. The majority of respondents were general dentists with more than 20 years in practice, who practice in a private setting, and see more than 10 patients in a day. All respondents stated they perform intraoral examinations, but 10 respondents stated they do not perform extraoral examinations. Nearly a third of respondents reported doing their own biopsies. Although only 8.5% of oral healthcare providers in Virginia responded to our survey, respondents are following the 2017 ADA good practice statement by providing their patients with head and neck exams to screen for oral cancer. Additional education pertaining to extraoral anatomy, malignant transformation of oral potentially malignant disorders, and pathology procedures may be helpful to clinicians.

Effect of Slice Thickness Variation on Spatial Resolution of CT-Scan Device Images at the Bali Mandara Hospital Radiology Installation

Aims: Slice thickness variation analysis on spatial resolution on CT-scan images by determining CNR and SNR values, by making ROI on object and background images. ROI size of objects and backgrounds can be observed with several criteria based on the provisions of the ACR program, so that optimization of CT-Scan image quality can be achieved.&#x0D; Place and Duration of Study: The Radiology Installation in Bali Mandara Hospital, between 23 March to 20 May 2022.&#x0D; Methodology: Data collection begins with preparing the equipment used, namely CT-Scan, head holder, phantom, and computer. After that, the head holder is placed in the middle of the gantry and then the phantom is placed with the guidance of the laser beam (alignment system). Set the axial beam on the vertical line of section 1 and then set the coronal beam on the horizontal line of section 2. After that, setting the type of examination using the adult head protocol and setting the scan parameters to 80 kV, 100 mAs, and slice thicknesses 1, 2, 3, 4, 6, and 8 mm. After the preparation is done then the next exposure to the phantom. Then the research data in the form of phantom images will be seen as a whole to program on the computer monitor. Measurements were made 5 times for each slice thickness. Next is to analyze the CNR of digital phantom image data on a computer. So that it can be determined object ROI, background ROI, object mean, background mean, and standard deviation of the background.&#x0D; Results: The results showed that the thicker the Slice Thickness, the higher the CNR and SNR values. The highest CNR value occurred in air medium (13.70) and the lowest occurred in Nylon (0.86). Likewise, the highest SNR value occurred in air medium (13.84) and the lowest in Nylon (0.99). The highest CNR and SNR values ​​occurred in air medium and the lowest occurred in Nylon. &#x0D; Conclusion: Slice Thickness variations affect the spatial resolution of CT-Scan images as indicated by the CNR and SNR values however, the CNR and SNR values ​​are still above 1.0 for adult head examination and above 0.7 for children's head examination. So that the quality of CT-Scan images at Bali Mandara Hospital is still very good.

Organ dose in CT: Comparison between measurements and computational methods

PurposeThis study aims to compare two methods for the organ dose evaluation in computed tomography (CT) in the head- and thorax regions: an experimental method, using radiochromic films, and a computational one, using a commercial software. MethodsGafchromic® XR-QA2 and EBT-3 were characterized in terms of energetic, angular, and irradiation configurations dependence. Two free-in-air irradiation calibration configurations were employed using a CT scanner: with the sensitive surface of the film orthogonal (OC) and parallel (PC) to the beam axis. Different dose–response curves were obtained by varying the irradiation configurations and the beam quality (BQ). Subsequently, films were irradiated within an anthropomorphic phantom using CT-thorax and -head protocols, and the organ dose values obtained were compared with those provided by the commercial software. ResultsAt different configurations, an unchanged dose response was achieved with EBT-3, while a dose response of 15% was obtained with XR-QA2. By varying BQ, XR-QA2 showed a different response below 10%, while EBT-3 showed a variation below 5% for dose values >20 mGy. For films irradiation angle equal to 90°, the normalized to 0° relative response was 41% for the XR-QA2 model and 83% for the EBT-3 one. Organ dose values obtained with EBT-3 for both configurations and with XR-QA2 for OC were in agreement with the DW values, showing percentage discrepancies of less than 25%. ConclusionsThe obtained results showed the potential of EBT-3 in CT patient dosimetry since the lower angular dependence, compared to XR-QA2, compensates for low sensitivity in the diagnostic dose range.