Computed Tomography Scan Of Neck Research Articles

Hyoid Position and Aging: A Comprehensive Analysis Using AI-assisted Segmentation of 282 Computed Tomography Scans.

With neck, aging the cervicomental angle becomes obtuse and may be influenced by hyoid bone aging. An understanding of hyoid position changes with aging will further our understanding of its role in neck contour changes. A 3D volumetric reconstruction of 282 neck computed tomography scans was performed. The cohort was categorized into three groups based on age: 20 years or older and younger than 40 years, 40 years or older and younger than 60 years, and 60 years or older and younger than 80 years. The vertical and horizontal hyoid distances in relation to the mandible were calculated for each patient. A total of 282 patients (153 women, 129 men) were included in the cohort. The age groups were evenly distributed in men and women. Mean hyoid vertical and horizontal distances differed between women and men in all age groups. There was a significant difference in the hyoid vertical distance between 20-39 years old to 40-59 years old in men (P < 0.01), and 20-39 years old to 60-79 years old in both genders (women P = 0.005, men P < 0.01). Hyoid horizontal distance was not affected by age and sex (age and sex: P > 0.05), but rather by body mass index (BMI). Every 5 BMI points corresponded to a forward movement of 2 mm. As individuals age, the hyoid bone descends in both sexes, and an increase in BMI is associated with forward movement. Additional studies are needed to assess the correlation of the hyoid position between upright and supine positions.

A new computed tomography-based approach to quantify swallowing muscle volume by measuring tongue muscle area in a single slice.

Measuring the swallowing muscle mass with volume measurements is complex and time intensive; therefore, it is not used in clinical practice. However, it can be clinically relevant, for instance, in the case of sarcopenic dysphagia. The aim of the study was to develop a feasible and clinically applicable method to measure swallowing muscle mass. Data from 10 head and neck cancer patients were collected from the Oncological Life Study data-biobank of the University Medical Center Groningen. The pharyngeal constrictor, genioglossus, mylohyoid and geniohyoid complex muscles, as well as the tongue complex muscles, were delineated manually on routinely performed head and neck computed tomography scans. Axial and sagittal planes were used for volume and area measurements, respectively. Muscle density measurements were performed with and without Hounsfield unit thresholding. Correlations were assessed by Pearson correlation coefficients, and interobserver reliability was measured using intra-class correlation coefficients (ICCs). Significant differences were observed between sagittal area measurements with and without Hounsfield unit thresholds for pharyngeal constrictor, tongue complex and the sum of the swallowing muscles (t>6; P-value<0.001). Stronger correlations emerged without Hounsfield unit thresholding. Strong positive and significant correlations were found between the total swallowing muscle mass volume and the sagittal area of the tongue complex muscles (r=0.87, P-value<0.05) and the sum of the sagittal areas of the pharyngeal constrictor and tongue complex muscles (r=0.85, P-value<0.05). The use of the Hounsfield unit threshold weakened correlations. Interobserver reliability was assessed and found to be fair to good for the pharyngeal constrictor muscle (ICC=0.68, P-value<0.05), excellent for the tongue complex muscles (ICC=0.98, P-value<0.05) and excellent for the total swallowing muscle area (ICC=0.96, P-value<0.05). Single-slice delineation of the sagittal area of tongue complex muscle and pharyngeal constrictor muscle is a promising, fast, simple and clinically applicable method for measuring the total volume of the swallowing muscle mass in head and neck cancer patients without Hounsfield unit thresholding. These advancements and findings would help in the early and accurate diagnosis of definitive sarcopenic dysphagia.

Nonmalignant tracheal stenosis: presentation, management and outcome in limited resources setting

BackgroundNonmalignant tracheal stenosis is a potentially life threatening conditions that develops as fibrotic healing from intubation, tracheostomy, caustic injury or chronic infection processes like tuberculosis. This is a report of our experience of its management with tracheostomy, rigid bronchoscopic dilation and surgery.MethodsRetrospective study design was used. 60 patients treated over five years period were included.ResultsMean age was 26.9 ± 10.0 with a range of 10–55 years. Majority (56 patients (93.3%)) had previous intubation as a cause for tracheal stenosis. Mean duration of intubation was 13.8 days (range from 2 to 27 days). All patients were evaluated with neck and chest CT (Computed Tomography) scan. Majority of the stenosis was in the upper third trachea − 81.7%. Mean internal diameter of narrowest part was 5.5 ± 2.5 mm, and mean length of stenosed segment was 16.9 ± 8 mm. Tracheal resection and end to end anastomosis (REEA) was the most common initial modality of treatment followed by bronchoscopic dilation (BD) and primary tracheostomy (PT). The narrowest internal diameter of the tracheal stenosis (TS) for each initial treatment category group was 4.4 ± 4.3 mm, 5.1 ± 1.9 mm and 6.7 ± 1.6 mm for PT, tracheal REEA and BD respectively, and the mean difference achieved statistical significance, F (10,49) = 2.25, p = 0.03. Surgery resulted in better outcome than bronchoscopic dilation (89.1% vs. 75.0%).Discussion and conclusionNonmalignant tracheal stenosis mostly develops after previous prolonged intubation. Surgical resection and anastomosis offers the best outcome.

Delayed diagnosis of Lemierre’s syndrome in a patient with severe coronavirus disease 2019: importance of comprehensive oral and neck examination – a case report

BackgroundGiven the widespread prevalence of the coronavirus disease 2019 (COVID-19), oral and neck examinations tend to be avoided in patients with suspected or confirmed COVID-19. This might delay the diagnosis of conditions such as Lemierre’s syndrome, which involves symptoms resembling COVID-19-related throat manifestations.Case presentationA 24-year-old man without any underlying conditions was diagnosed with COVID-19 7 days before presentation. He was admitted to another hospital 1 day before presentation with severe COVID-19 and suspected bacterial pneumonia; accordingly, he was started on treatment with remdesivir and meropenem. Owing to bacteremic complications, the patient was transferred to our hospital for intensive care. On the sixth day, the patient experienced hemoptysis; further, a computed tomography (CT) scan revealed new pulmonary artery pseudoaneurysms. Successful embolization was performed to achieve hemostasis. In blood cultures conducted at the previous hospital, Fusobacterium nucleatum was isolated, suggesting a cervical origin of the infection. A neck CT scan confirmed a peritonsillar abscess and left internal jugular vein thrombus; accordingly, he was diagnosed with Lemierre’s syndrome. The treatment was switched to ampicillin/sulbactam, based on the drug susceptibility results. After 6 weeks of treatment, the patient completely recovered without complications.ConclusionThis case highlights the significance of thorough oral and neck examinations in patients with suspected or diagnosed COVID-19 for the detection of throat and neck symptoms caused by other conditions.

Insights about cervical lymph nodes: Evaluating deep learning–based reconstruction for head and neck computed tomography scan

PurposeThis study aimed to investigate differences in cervical lymph node image quality on dual-energy computed tomography (CT) scan with datasets reconstructed using filter back projection (FBP), hybrid iterative reconstruction (IR), and deep learning–based image reconstruction (DLIR) in patients with head and neck cancer. MethodSeventy patients with head and neck cancer underwent follow-up contrast-enhanced dual-energy CT examinations. All datasets were reconstructed using FBP, hybrid IR with 30 % adaptive statistical IR (ASiR-V), and DLIR with three selectable levels (low, medium, and high) at 2.5- and 0.625-mm slice thicknesses. Herein, signal, image noise, signal-to-noise ratio, and contrast-to-noise ratio of lymph nodes and overall image quality, artifact, and noise of selected regions of interest were evaluated by two radiologists. Next, cervical lymph node sharpness was evaluated using full width at half maximum. ResultsDLIR exhibited significantly reduced noise, ranging from 3.8 % to 35.9 % with improved signal-to-noise ratio (11.5–105.6 %) and contrast-to-noise ratio (10.5–107.5 %) compared with FBP and ASiR-V, for cervical lymph nodes (p < 0.001). Further, 0.625-mm-thick images reconstructed using DLIR-medium and DLIR-high had a lower noise than 2.5-mm-thick images reconstructed using FBP and ASiR-V. The lymph node margins and vessels on DLIR-medium and DLIR-high were sharper than those on FBP and ASiR-V (p < 0.05). Both readers agreed that DLIR had a better image quality than the conventional reconstruction algorithms. ConclusionDLIR-medium and -high provided superior cervical lymph node image quality in head and neck CT. Improved image quality affords thin-slice DLIR images for dose-reduction protocols in the future.

Baş boyun kanserli hastalarda tek gen polimorfizmi ile sisplatin ve 5-FU tedavisine yanıt arasındaki ilişki

Amaç: Baş ve boyun kanserleri dünya çapında en sık görülen altıncı kanser türüdür. Baş ve boyun kanserlerinin tedavi süreci kemoterapi veya kemoradyoterapi olarak sınıflandırılır. Bu çalışmada ERCC1, XRCC1 ve MTHFR genlerinin tedavi ile yanıt ilişkisi araştırıldı.&#x0D; Gereç ve Yöntemler: Çalışmada tek nükleotid polimorfizmini araştırmak amacıyla hastalardan 5 ml kan alınarak DNA izole edildi ve pirosequencing yöntemiyle araştırıldı.&#x0D; Bulgular: Hastalar RECIST kriterlerine göre değerlendirildi; tedaviden önce (4 hafta) ve her üç siklustan sonra baş ve boyun bilgisayarlı tomografi taramaları yapıldı. Genel yanıt oranı (RR) 10 (%25) PD, 7 (%17,5) SD, 9 (%22,5) PR ve 14 (%35) CR idi. En az bir polimorfik varyantı olan hastaların dördünde PD, 3'ünde SD, 3'ünde PR ve 1'inde CR vardı.&#x0D; Sonuçlar: Bu çalışmada bir grup baş boyun karsinomu hastasının klinik davranışı, üç tek nükleotid polimorfizmi ile ilişki açısından retrospektif olarak değerlendirildi. Bunlar arasında ERCC1 geninde C8092A, XRCC1 geninde G28152A ve MTHFR geninde C677T ve A1298C yer alıyordu.

Computed tomography in measuring electrode insertion angle and depth for cricopharyngeal muscle electromyography.

Electromyography of the cricopharyngeal muscle (CP-EMG) is one of many assessment tools for dysphagia. The key to performing EMG and BTX injections is to precisely locate the cricopharyngeal muscle with an electrode. One of the main difficulties of electrode insertion is the fact that the CP muscle is located deep within the neck. Since a neck computed tomography (CT) can clearly display the CP muscle, thyroid, and blood vessels in the neck, we speculate that a safe concentric needle electrode insertion path to the cricopharyngeal muscle can be simulated with the assistance of the patient's neck CT which clearly marks the angle and depth of concentric needle electrode insertion. The purpose of this study was to explore simulated electrode insertion angles and insertion depths for cricopharyngeal electromyography based on retrospective CT data and present a method of percutaneous localization of the cricopharyngeal muscle based on CT images of the neck. One hundred and forty-three neck CT scans performed between January 2019 and November 2020 were included in this study. With the assistance of the angle and straight-line tools found in the Advantage Workstation 4.4 (GE, HealthCare), simulated insertion angles and depths from the anterior border of the sternocleidomastoid muscle to the cricopharyngeal muscle were obtained. The 143 CT images originated from participants that included 63 males (44.1%) with an average age of 46.2±13.9 years old. The insertion angle, insertion depth, and neck thickness measured on the CT images were 53.2±10.7˚, 24.2±4.1 mm, and 130.1±17.7 mm, respectively. The insertion angle and depth were significantly greater in males than in females (P<0.05), and the insertion angle increased with the age of participants (P<0.05). A generalized linear model (GLM) showed that insertion angle was positively correlated with neck thickness (β=0.14; 95% CI: 0.03 to 0.25) and gender (β=5.08; 95% CI: 1.31 to 8.85), and negatively correlated with age (β=-5.88; 95% CI: -9.54 to -1.62). Insertion depth was only positively correlated with the neck thickness (β=0.11; 95% CI: 0.07 to 0.15). This study indicates that age, gender, and neck thickness are influencing factors for insertion angle, while neck thickness is the influencing factor for insertion depth. The simulated concentric needle electrode insertion method based on CT can assist clinical operation to ensure safety and effectiveness of cricopharyngeal electromyography.

Morphological analysis of C2-C7 spinous process bifurcation in Chinese population: a study using three-dimensional reconstruction of computed tomography.

This study aimed to investigate the anatomical morphology of the C2 to C7 spinous process (SP) bifurcation (SPB) in the Chinese population and reveal its potential clinical significance. Measurement parameters of the three-dimensional (3D) reconstructions of neck computed tomography scans (n = 92 scans) were retrospectively analysed. The 3D reconstruction and measurements were performed using Mimics Research 19.0 and 3-Matic Research 11.0. Two independent investigators reviewed all the data, including parameters such as the length and angle of the SPB. The effects of age and sex were also analysed. We identified four morphological types of SPB: fully bifid (n = 252, 45.65%), partially bifid (n = 65, 11.78%), non-bifid (n = 226, 40.94%) and unilateral branch (n = 9, 1.63%). The Kappa coefficients indicated good inter-observer reproducibility (0.776), and the intraclass correlation coefficients (ICC) values demonstrated excellent intra-rater reliability (ICC = 0.9, p < 0.0001) in the classification and measurement of SPB parameters. The percentage of general bifid SP was more than 70% in C2-5 and about 21% in C6, while all C7 SPs presented non-bifid. Morphology was symmetrical in bifid and partially bifid SP, while unilateral SP was not. The classification system of SPB in this study proved consistent and reliable, despite the subjective bias. Identifying the cervical level by C6 bifurcation is unreliable, as nearly 80% of C6 SP is non-bifid. Our work provides an accurate and effective anatomical reference for SPB studies in the Chinese population.

Radiological Study of Atlas Arch Defects with Meta-Analysis and a Proposed New Classification.

This study consists of a retrospective cohort study, a systematic review, and a meta-analysis which were separately conducted. This study aimed to investigate the prevalence of atlas arch defects, generate an evidence-based synthesis, and propose a common classification system for the anterior and combined atlas arch defects. Atlas arch defects are well-corticated gaps in the anterior or posterior arch of the atlas. When both arches are involved, it is known as a combined arch defect. Awareness of these defects is essential for avoiding complications during surgical procedures on the upper spine. The prevalence of arch defects was investigated in an open-access OPC-Radiomics (Radiomic Biomarkers in Oropharyngeal Carcinoma) dataset comprising 606 head and neck computed tomography scans from oropharyngeal cancer patients. A systematic review and meta-analysis were performed to generate prevalence estimates of atlas arch defects and propose a classification system for the anterior and combined atlas arch defects. The posterior arch defect was found in 20 patients (3.3%) out of the 606 patients investigated. The anterior arch defect was not observed in any patient, while a combined arch defect was observed in one patient (0.2%). A meta-analysis of 13,539 participants from 14 studies, including the present study, yielded a pooled-posterior arch defect prevalence of 2.07% (95% confidence interval [CI], 1.22%-2.92%). The prevalences of anterior and combined arch defects were 0.00% (95% CI, 0.00%-0.10%) and 0.14% (95% CI, 0.04%-0.25%), respectively. The anterior and combined arch defects were classified into five subtypes based on their morphology and frequency. The present study showed that atlas arch defects were present in approximately 2% of the general population. For future studies, larger sample sizes should be used for studying arch defects to avoid the small-study effect and to predict the prevalence accurately.

Organ doses, effective dose, and cancer risk estimation from head and neck CT scans

PurposeThe goal of this study was to calculate the organ doses, effective doses, and cancer risk from head and neck computed tomography (CT) scans. Material and methodsAll patients underwent topogram, base, and cerebrum sequences during their head and neck examinations. Two techniques were used to determine the effective dose (ED). The first was based on the scanner derived dose length product, while the second involved using the software that calculated the organ and effective doses. Organ doses were computed using the tissue weighting factors from Report 103 by the International Commission on Radiation Protection (ICRP). The cancer risk values were calculated using web-based software that is based on the BEIR VII Phase 2 report. ResultsThere were 293 patients in this study (189 males, 104 females). The overall mean effective dose in the females was higher than that in the males (2.19 vs. 2.06 mSv). Male patients had a mean cancer risk of 0.011%, whereas female patients had a mean cancer risk of 0.015%. The younger females had much higher cancer risk values. ConclusionThe findings of this study will assist physicians in justifying and optimizing dose administration of head and neck CT examinations by weighing the benefits of diagnosis on the one hand and awareness of cancer risk on the other.

Tracheal hemangioma: a case report and literature review.

An 8-year-old boy with the chief complaint of severe progressive dyspnea and a history of neonatal postbreastfeeding cyanosis was admitted. On physical examination, he had tachypnea, and stridor was heard upon auscultation. There was no history of fever, chest pain, or coughing. He underwent a rigid bronchoscopy followed by a neck computed tomography scan. The results indicated a soft tissue mass with a vascular nature. An MRI of the neck confirmed the diagnosis of tracheal hemangioma. The mass was not resectable during surgery; hence, angioembolization was carried out. Treatment was successful and there was no recurrence on the follow-up. Based on the findings in this literature review tracheal hemangiomas present with stridor, progressive respiratory distress, dyspnea, hemoptysis, and chronic coughs. Advanced tracheal hemangiomas commonly do not reduce in size by themselves and need treatment. A close follow-up ranging from 3 months to 1 year is recommended. Although tracheal hemangiomas are rare they should be considered in the differential diagnosis of severe dyspnea and stridor.

EVALUATION OF RADIATION DOSE IN MULTI-SLICE COMPUTED TOMOGRAPHY PROTOCOLS OF HEAD AND NECK REGIONS.

In head and neck computed tomography (CT) imaging, the optimisation of radiation dose is crucial due to the presence of radio-sensitive organs. This study aimed to evaluate the radiation dose in multi-slice CT for head and neck examinations. Volume CT dose index, dose length product and effective dose (E) were assessed for 10 head and neck CT scans performed on 292 adult patients (mean age 49.2±15.9y). The study resulted in median E values of 0.82, 1.62, 2.43, 0.93, 1.70, 0.83, 3.55, 6.25, 2.19 and 5.26mSv, respectively, for sinuses (non-contrast (NC)), sinuses (NC) and contrast-enhanced (CE), petrous bone (PTB)/internal auditory meatus (IAM) (NC+CE), PTB/IAM (NC), orbit (NC+CE), orbit (NC), brain with the orbit (NC), brain CT angiography (CTA) subtraction, neck (NC) and brain/neck (NC). Furthermore, the overall radiation doses of this institution were found to be below the values suggested by similar studies. However, optimisation of the dose is required for brain CTA.

Anatomical Variants Identified on Computed Tomography of Oropharyngeal Carcinoma Patients.

Background and Objectives: Anatomical variations in the head, neck and chest are common, and are observed as occasional findings on computed tomography (CT). Although anatomical variations are mostly asymptomatic and do not cause any negative influence on the body function, they may jeopardize diagnosis and may be confused with pathological conditions. The presence of variations may also limit surgical access during tumor removal. The aim of this study was to investigate the prevalence of six anatomical variations-os acromiale, episternal ossicles, cervical rib, Stafne bone cavity, azygos lobe and tracheal bronchus-in an open-access computed tomography dataset obtained from oropharyngeal cancer patients. Materials and Methods: A total of 606 upper-chest and neck computed-tomography scans (79.4% male and 20.6% female) were retrospectively investigated. Sex difference was evaluated using the z-test for two proportions. Results: Os acromiale, episternal ossicles, cervical rib, Stafne bone cavity, azygos lobe, and tracheal bronchus were present in 3.1%, 2.2%, 0.2%, 0%, 0.3% and 0.5%, respectively, of all patients. Os acromiale was identified as meso-acromion in 86.6%, and as pre-acromion in 17.4%, of all acromia. Episternal ossicles were present unilaterally in 58.3%, and bilaterally in 41.7%, of all sterna. Only the cervical rib showed a sex difference in prevalence. Conclusions: awareness of these variations is important for radiologists interpreting head, neck and chest CTs; for example, those of oropharyngeal cancer patients. This study also illustrates the applicability of publicly available datasets in prevalence-based anatomical research. While most of the variations investigated in the present study are well-known, the episternal ossicles are not well explored, and need further investigation.

Schwannoma of the ansa cervicalis masquerading as a thyroid nodule: a multimedia case report and literature review

Background: Schwannomas originating from the ansa cervicalis represent an exceptionally infrequent occurrence. To date, less than five cases have been reported in the English literature. We present a multimedia case report of an ansa cervicalis schwannoma, accompanied by a surgical video, in a patient whose initial clinical assessment suggested potential thyroid pathology. Case Presentation: A 51-year-old woman was referred to the otolaryngology department following an incidental finding of a thyroid nodule on a head and neck computed tomography scan. Imaging revealed the presence of two lesions: a TIRADS 3 left thyroid nodule, and a benign tumor originating from the peripheral nerve sheath of the ansa cervicalis, located adjacent to the right thyroid lobe. Intraoperatively, the second lesion was discovered to originate from a branch of the superior root of the ansa cervicalis. Subsequent histopathological analysis confirmed the diagnosis of a schwannoma. Conclusion: Schwannomas originating from the ansa cervicalis pose a diagnostic challenge, often susceptible to misinterpretation and confusion with other lesions. This case report highlights radiological and surgical techniques that can be used to identify the origin of these tumors, both preoperatively and intraoperatively.

Prediction of obstructive sleep apnea using deep learning in 3D craniofacial reconstruction.

Obstructive sleep apnea (OSA) is a common sleep disorder. However, current diagnostic methods are labor-intensive and require professionally trained personnel. We aimed to develop a deep learning model using upper airway computed tomography (CT) to predict OSA and to warn the medical technician if a patient has OSA while the patient is undergoing any head and neck CT scan, even for other diseases. A total of 219 patients with OSA [apnea-hypopnea index (AHI) ≥10/h] and 81 controls (AHI <10/h) were enrolled. We reconstructed each patient's CT into 3 types (skeletal structures, external skin structures, and airway structures) and captured reconstructed models in 6 directions (front, back, top, bottom, left profile, and right profile). The 6 images from each patient were imported into the ResNet-18 network to extract features and output the probability of OSA using two fusion methods: Add and Concat. Five-fold cross-validation was used to reduce bias. Finally, sensitivity, specificity, and area under the receiver operating characteristic curve (AUC) were calculated. All 18 views with Add as the feature fusion performed better than did the other reconstruction and fusion methods. This gave the best performance for this prediction method with an AUC of 0.882. We present a model for predicting OSA using upper airway CT and deep learning. The model has satisfactory performance and enables CT to accurately identify patients with moderate to severe OSA.

A Rare Case of a Retroperitoneal Paraganglioma: A Case Report

Retroperitoneal paraganglioma is a rare neoplasm that develops from chromaffin cells that secrete catecholamines in the sympathetic ganglia. They are frequently functional and may be benign or malignant depending on the presence of metastasis and/or the occurrence of recurrence. Different imaging modalities play a crucial role in detecting these tumors. The typical CT appearance of PG is that of a well limited isodense mass with an intense contrast enhancement. On MRI, the mass presents an isosignal or hyposignal in T1 and hypersignal in T2 with an early and intense enhancement. The final diagnosis is based on histological and immunohistochemical findings and the surgical excision is the mainstay of the treatment. However, these tumors are often difficult to diagnose and treat. We report a case of a 30-year-old female patient who presented with a 3 months history of constipation, revealing on computed tomography (CT) a retroperitoneal mass lateralized on the right with a close connection to the inferior vena cava. Urine normetadrenaline (metanephrine) was elevated at 451 ug/24h. Neck and chest CT scan and scintigraphy with 123-I labeled metaiodobenzylguanidine (MIBG) were negative. Complete resection of the tumor was performed. The histological examination and immunohistochemical analyses concluded the diagnosis of a paraganglioma.

BURKITT'S LYMPHOMA: MULTIPROFESSIONAL DIAGNOSTIC VIEW OF A DIFFICULT CASE

Burkitt's lymphoma (BL) is an aggressive form of non-Hodgkin's B-cell lymphoma that presents 3 forms: endemic, sporadic, and immunodeficiency-associated types. The objective is to report a case of BL diagnosed in the mandibular gingiva based on the initial manifestation of right axillary lymph node enlargement (>15 cm). Upon examination, an exophytic lesion was noted in the mandible, posterior region, bilateral, invading masticatory space. A head and neck computed tomography scan revealed a homogeneous solid expansive lesion in the right buccinator space, extending to retromaxillary fat. The anatomopathologic report was compatible with BL. The patient was treated with R-dose adjusted rituximab, etoposide, prednisone, vincristine, cyclophosphamide and doxorubicin and is being followed up with a reduction in the mass of lymph nodes and oral lesions. We concluded that the multiprofessional approach in conducting diagnosis is important for the best treatment. Also, it showed that the diagnosis of hematological neoplasm must include several professionals, making the treatment more individualized for the patient.

Effective radiation doses in neck computed tomography scans

A significant source of ionizing radiation for medical use is computed tomography (CT). According to estimates, more than 84 million CT scans are carried out yearly in the US. Because the neck area contains several organs and tissues that are very sensitive to ionizing radiation, such as the thyroid gland, CT for the neck region is commonly done for a variety of clinical causes. This study's goal is to assess the patient doses to radiosensitive organs and effective doses received during the CT neck surgery in the pastAt Riyadh Care Hospital, a multislice CT (MSCT) system (Siemens Somatom Sensation, 64 slices/detector) was used to perform improved CT treatments on a total of 54 patients. Patient ages were 41.5–15.5 years old on average, with a wide variation (21–73). Using computer software based on Monte Carlo simulation, organ and effective dosages were assessed. The International Commission of Radiological Protection (ICRP) risk variables were used to calculate the patient's radiogenic risk for a particular organ. The patients' dose length product (DLP, mGy.cm) for CT neck examination were 993.3 ± 539.5 (267.3–2441.7). The mean and range of volume CT dose per slice (CTDIvol (mGy)) were 1.5 ± 3.9 (3.91–22.55). The overall effective dose (mSv) per procedure is ranged from 1.3 to 11.7 with a mean value 2.8 mSv. Patients' CT neck procedures have been repeated the procedure up to 7 times during the treatment course. The risk of malignancy is 1x10-6 CT procedure. The study showed that patients received wide discrepancies in patients' doses up to 9 times. Optimization of image acquisition protocol and scan length is necessary to reduce the unnecessary risk.

U-net architecture with embedded Inception-ResNet-v2 image encoding modules for automatic segmentation of organs-at-risk in head and neck cancer radiation therapy based on computed tomography scans

Purpose. The purpose of this study was to utilize a deep learning model with an advanced inception module to automatically contour critical organs on the computed tomography (CT) scans of head and neck cancer patients who underwent radiation therapy treatment and interpret the clinical suitability of the model results through activation mapping. Materials and methods. This study included 25 critical organs that were delineated by expert radiation oncologists. Contoured medical images of 964 patients were sourced from a publicly available TCIA database. The proportion of training, validation, and testing samples for deep learning model development was 65%, 25%, and 10% respectively. The CT scans and segmentation masks were augmented with shift, scale, and rotate transformations. Additionally, medical images were pre-processed using contrast limited adaptive histogram equalization to enhance soft tissue contrast while contours were subjected to morphological operations to ensure their structural integrity. The segmentation model was based on the U-Net architecture with embedded Inception-ResNet-v2 blocks and was trained over 100 epochs with a batch size of 32 and an adaptive learning rate optimizer. The loss function combined the Jaccard Index and binary cross entropy. The model performance was evaluated with Dice Score, Jaccard Index, and Hausdorff Distances. The interpretability of the model was analyzed with guided gradient-weighted class activation mapping. Results. The Dice Score, Jaccard Index, and mean Hausdorff Distance averaged over all structures and patients were 0.82 ± 0.10, 0.71 ± 0.10, and 1.51 ± 1.17 mm respectively on the testing data sets. The Dice Scores for 86.4% of compared structures was within range or better than published interobserver variability derived from multi-institutional studies. The average model training time was 8 h per anatomical structure. The full segmentation of head and neck anatomy by the trained network required only 6.8 s per patient. Conclusions. High accuracy obtained on a large, multi-institutional data set, short segmentation time and clinically-realistic prediction reasoning make the model proposed in this work a feasible solution for head and neck CT scan segmentation in a clinical environment.

Migration of a Fish Bone From the Esophagus to the Thyroid Gland.

Accidental swallowing of fish bone is one of the most common emergencies in the otolaryngology department. The impacted fish bones are usually found in the palatine tonsil, base of the tongue, valleculae, pyriform sinus, and esophagus, which can be successfully removed after a thorough examination. However, in some cases, the fish bone may penetrate into the neck soft tissue and migrate to extraluminal organs, causing infection, abscess formation, or rupture of vessels. In such cases, prompt recognition and immediate removal of the impacted fish bone are necessary. Herein, we report a rare case of a 60-year-old woman who had accidently swallowed a fish bone 10days prior to visiting the outpatient department. The fiberoptic scope and head and neck computed tomography scans were obtained from the outpatient department. The fish bone was found to migrate from the upper esophagus to the left thyroid gland. First, a rigid esophageal endoscopy was performed in the operating room, but no obvious fish bone was noted over the esophagus. Finally, the fish bone was removed via exploratory cervicotomy with left-sided total lobectomy of the thyroid. The patient recovered after the operation, and there were no further complications during the 3years of follow-up.