Computed Tomography Scan Research Articles

Computed tomographic analysis of the frontal sinus morphology and structures that affect the size of the frontal sinus outflow tract in Vietnamese people

The frontal recess is a relatively small and narrow area with many neighboring structures and is very diverse in each body. Surgical intervention in this area is still challenging for surgeons. The International Frontal Sinus Anatomy Classification (IFAC) helps classify frontal cells on computed tomography (CT) scans for surgical purposes and anatomical accuracy. This study aims to investigate the morphology of the frontal sinus, the anteroposterior (A-P) diameter of the frontal sinus ostium and the A-P diameter of the frontal recess, the frontal cells classified by IFAC and the relationships between frontal sinus characteristics and A-P diameter of frontal sinus ostium and frontal recess on CT scans. Descriptive cross-sectional study on all CT scans of nasal cavities and paranasal sinuses of patients ≥ 20 years old at the Examination Department of Minh Duc Hospital — Ben Tre and Can Tho University of Medicine and Pharmacy Hospital. In terms of morphology, we found that the most common type was large-sized frontal sinus (40.7%), followed by medium (35.4%) and small (23.9%), respectively. The three dimensions of the frontal sinus in men were larger than in women (p<0.05). The mean A-P diameter of frontal sinus ostium was 6.41±2.66 mm. The mean A-P diameter of frontal sinus recess was 3.23 ± 2.59 mm. The agger nasi cells accounted for the highest proportion (93.6%) and supraorbital ethmoid cells accounted for the lowest proportion (2.9%). There was a statistically significant relationship between ostium diameter and frontal sinus morphology with p<0.001. The A-P diameter of the frontal sinus ostium and frontal recess became narrower with the appearance of the frontal cells. From the study’s results about the frontal sinus morphology, the relationship between the frontal recess cells and the structures affecting the anteroposterior diameter of the frontal sinus drainage pathway can assist surgeons in planning effective and safe surgical interventions in the frontal sinus area.

Age- and sex-adjusted CT-based reference values for temporal muscle thickness, cross-sectional area and radiodensity

Muscle mass has been traditionally assessed by measuring paraspinal muscle areas at the level of the third lumbar vertebra on computed tomography (CT). Neurological or neurosurgical patients seldom undergo CT scans of the lumbar region. Instead, temporal muscle thickness (TMT), cross-sectional area (TMA) and radiodensity measured from head CT scans are readily available measures of muscle mass and quality in these patient cohorts. The purpose of this retrospective study was to establish CT-based reference values for TMT, TMA and radiodensity for each decade of age from 0 to 100 years normalized by age and sex, and to define cut-off values for subjects at risk for sarcopenia as defined by the European Working Group on Sarcopenia in Older People (EWGSOP). Subjects diagnosed with a concussion at the Oulu University Hospital between January 2014 and December 2022 (n = 9254) were identified to obtain a reference population. Subjects with significant pre-existing co-morbidities were excluded. TMT, TMA and radiodensity were measured, measurement reliability was quantified, and sex-adjusted reference values were calculated for each age decade. Quantile regression was used to model age-related changes in muscle morphomics. A total of 500 subjects [250 (50.0%) males] with a mean age of 49.2 ± 27.9 years were evaluated. Inter- and intra-observer reliability was almost perfect for TMT and TMA, and substantial-to-almost perfect for radiodensity. The mean TMT, TMA and radiodensity were 5.2 ± 1.9 mm, 284 ± 159 mm2 and 44.6 ± 17.7HU, respectively. The cut-off values for reduced TMT, TMA and radiodensity for males/females using the European Working Group on Sarcopenia in Older People compliant criteria were ≤ 4.09 mm/≤3.44 mm, ≤ 166 mm2/≤156 mm2, and ≤ 35.5HU/≤35.2HU, respectively. We described a standardized CT-based TMT and TMA measurement protocol practical for clinical use with almost perfect reliability. Using the protocol, we produced quantile regression models for the detection of reduced TMT, TMA and radiodensity at the lowest 5th, 10th, 20th, 30th, 40th and 50th percentiles as well as the EWGSOP compliant criteria cut-off values for reduced muscle mass to facilitate generalizable radiological sarcopenia research.

Muscle Loss During First-Line Chemotherapy Impairs Survival in Advanced Pancreatic Cancer Despite Adapted Physical Activity.

Advanced pancreatic ductal adenocarcinoma (aPDAC) is often accompanied by significant muscle mass loss, contributing to poor prognosis. SarcAPACaP, an ancillary study of the GERCOR-APACaP phase III trial, evaluated the role of adapted physical activity (APA) in aPDAC Western patients receiving first-line chemotherapy. The study aimed to assess (1) the potential impact of computed tomography (CT)-quantified muscle mass before and during treatments on health-related quality of life (HRQoL) and overall survival (OS) and (2) the role of APA in mitigating muscle mass loss. In the APACaP trial, aPDAC patients with ECOG performance status (PS) 0-2 were randomized 1:1 to usual care including first-line chemotherapy or usual care plus a 16-week home-based APA program. In the SarcAPACaP study, the surface muscular index (SMI) was determined from L3 CT scan slices. Two patient populations were analysed: those with CT scan available at baseline (modified[m] intent-to-treat [ITT]1-W0) and those with CT scans available at both W0 and W16 (mITT2 W0-W16). Low muscle mass was defined by low SMI with SMI < 41 cm2/m2 for women and < 43 and < 53 cm2/m2 for men with body max index < 25.0 and ≥ 25.0 kg/m2, respectively. Muscle loss was defined by the relative difference of SMI between W0 and W16 (100*[SMI W16-SMI W0]/SMI W0). In mITT2 W0-W16, patients were stratified into three groups based on the severity of muscle loss: none, moderate (0%-10%) and high (≥ 10%). Associations between muscle mass loss and OS, time until definitive deterioration (TUDD) of HRQoL and the effect of APA on loss of muscle mass were assessed. Between October 2014 and May 2020, 313 patients were prospectively enrolled, with 225 in mITT1 W0 and 128 in mITT2 W0-W16, with 65 assigned to the APA arm. Both groups had similar baseline characteristics with comparable OS and TUDD. A low SMI at W0 was not associated with OS and TUDD of HRQoL in either group. Among mITT2 W0-W16 patients, high muscle mass loss (n = 27) independently predicted OS (p = 0.012) and showed a trend toward negatively affecting TUDD of HRQoL. Notably, APA did not mitigate muscle loss in our study population. Longitudinal muscle mass loss emerged as a predictive factor for both OS and HRQoL in aPDAC patients undergoing chemotherapy, while a low SMI at diagnosis did not provide prognostic value. APA did not impact muscle mass loss in this population.

EP69 Real Life Assessment of Diagnostic Imaging In Acute Appendicitis. A Multi-Centre Audit from The United Kingdom

Abstract Objectives Ultra-sound scan (USS) and Computed Tomography (CT) are commonly used in the diagnosis of acute appendicitis (AA). This audit aims at assessing their sensitivity and implications on the rate of negative appendicectomy (NA) and the number of scans patients have. Methods This is a retrospective multi-centre audit from tertiary (TH) and secondary (SH) hospitals in the United Kingdom. We enrolled patients who underwent appendicectomy over the last year and compared their scans findings to the histopathological findings as the gold standard for AA. Results This is a preliminary report of the first 405 (49.4% females). 69% had USS and 51% had CT scan. USS sensitivity was 57.6%. This sensitivity did not change significantly with age, sex or the size of hospital. CT sensitivity was 95.7%. Females and SH patients tended to have more scans (p&amp;lt; 0.001 for both). 26.4% of the patients had no scans and underwent appendicectomy based on clinical diagnosis. The positive predictive value of this clinical diagnosis was 85% which is equal to USS. 12.1% of the patients had NA, of which 16.4% were females Vs 7.8% males (p= 0.008). The mean age in NA was 26.96 years old Vs 34.12 years old in positive appendicectomy (p=0.009). Conclusion USS sensitivity is low and does not improve in females or younger patients who are also more likely to have NA. Females and SH patients are more likely to have more scans. Findings of USS should be interpreted with care, especially in young and female patients.

Deep Learning-Derived Quantitative Scores for Chronic Rhinosinusitis Assessment: Correlation With Quality of Life Outcomes.

Computed tomography (CT) plays a crucial role in assessing chronic rhinosinusitis, but lacks objective quantifiable indicators. This study aimed to use deep learning for automated sinus segmentation to generate distinct quantitative scores and explore their correlations with disease-specific quality of life. From July 2021 to August 2022, 445 CT data were collected from 2 medical centers. A deep learning model based on nnU-Net was trained for automatic sinus segmentation and internally validated using 300 cases. The remaining 145 cases were split into an external testing set (74 cases) and an independent testing set (71 cases). Two quantitative scores, the quantitative Lund-MacKay score and the quantitative opacification score (QOS), were derived from the segmentation results. The quantitative scores' efficacy was assessed by comparing them with the Lund-MacKay score (LMS), the 22-item Sinonasal Outcome Test score (SNOT-22), and other clinical variables through correlation analyses. Furthermore, the relationship between quantitative scores and postoperative quality of life improvement was explored using single-factor logistic regression. The segmentation model achieved average Dice similarity coefficients of 0.993, 0.978, 0.958, and 0.871 for the training, validation, external testing, and independent testing sets, respectively. Both quantitative scores significantly correlated with the LMS (rho = 0.87 and rho = 0.70, P < .001). Neither score correlated with the total SNOT-22 score, although the modified QOS showed significant correlations with the nasal and sleep subdomains (rho = 0.26 and rho = 0.27, P < .05). No significant association was found between quantitative score and postoperative improvement in quality of life. Deep learning enables the automated segmentation of sinuses on CT scans, producing quantitative scores of sinus opacification. These automatic quantitative scores may serve as tools for chronic rhinosinusitis assessment.

EP72 Assessing the Utility of Abdominal X-Rays in Emergency Settings: Are They Adding Value?

Abstract Background The clinical value of abdominal X-rays (AXRs) in emergency departments (EDs) is debated, particularly with the availability of advanced imaging modalities like ultrasound (US) and computed tomography (CT). Despite the 2016 Royal College of Radiologists (RCR) guidelines limiting AXR use to specific indications, concerns about their overuse persist. Methods A retrospective observational study was conducted from January 1st to March 31st, 2023, in a London district general hospital. We evaluated 473 patients who underwent AXRs, examining compliance with RCR guidelines, clinical indications, AXR findings, follow-up imaging, and referrals to General Surgery. Pearson’s chi-squared test was used for statistical analysis, with significance set at p &amp;lt; 0.05. Results 81.6% of AXRs met RCR guidelines, primarily for suspected bowel obstruction; however, only 11.4% of patients had all three key symptoms (abdominal pain, vomiting, failure to open bowels). Follow-up imaging was performed in 37.6% of cases, mainly CT scans. Abnormal findings were noted in 15% of AXRs, but 63.4% of these required additional imaging. Significant associations were found between abnormal AXRs and General Surgery referrals, as well as between referrals and subsequent CT scans. Conclusions AXRs are frequently overused in the ED, with limited diagnostic value. Even when AXRs identify abnormalities, CT follow-up is often required, suggesting AXRs may not significantly alter management. Reconsidering the role of AXRs in ED practice and promoting advanced imaging modalities could enhance diagnostic efficiency and reduce unnecessary resource use.

Radiation Dose Optimization: Range Configuration on Computed Tomography Scans of Non-Contrast Head Scans with Hemiparese Cases

Radiation Dose Optimization: Range Configuration on Computed Tomography Scans of Non-Contrast Head Scans with Hemiparese Cases

What is the frequency of anterior syndesmosis injury in posterior malleolus fracture?

BackgroundPosterior malleolus fractures may be fixed to restore syndesmosis stability. However, these fractures are often accompanied by ruptures of other ligaments that stabilize the syndesmosis. This study investigates the frequency of anterior syndesmosis injury in posterior malleolus fractures and its effect on rotational stability.MethodsSeventy-five consecutive patients who underwent surgery for ankle fractures involving posterior malleolus were prospectively included. Preoperative computed tomography scans in two planes (transverse and sagittal) were used to assess the presence and size of avulsion fractures (LeFort-Wagstaffe and Tillaux-Chaput). Intraoperatively, anterior syndesmosis injuries and rotational stability (determined via the external rotation test) were assessed through direct visualization.ResultsIn 73 patients (97%), a complete injury of the anterior tibiofibular ligament was observed intraoperatively, manifesting as avulsion fractures (8%), ligament injuries (44%), or a combination of both (45%). The mean dimensions of the avulsion fractures were 12.6 mm × 7.5 mm for LeFort-Wagstaffe fractures and 12.4 mm × 7.9 mm for Tillaux-Chaput fractures. Posterior malleolus fractures were stabilized in 57 patients. In 52 of these cases (92%), syndesmosis instability in the direction of external rotation persisted despite fixation of the posterior malleolus.ConclusionsFixation of posterior malleolus fractures is rarely sufficient to fully restore syndesmosis stability. Post-fixation assessment of syndesmosis stability, particularly in external rotation, is essential.

Cholecystogastric fistula presenting as pyloric obstruction - a Bouveret’s syndrome: A case report

BACKGROUND Bouveret’s syndrome is a rare (1%-4%) form of cholelithiasis characterized by gastric outlet obstruction. It presents mainly in elderly women with nausea, vomiting, and abdominal pain. On physical examination, common findings include dehydration signs such as tachycardia, decreased urine output, abdominal discomfort, and distention. Diagnosis relies on computed tomography (CT) and magnetic resonance imaging, with Rigler's triad (pneumobilia, ectopic gallstone, gastric distension) being highly specific. This report aims to improve understanding of Bouveret’s syndrome and inform better management and treatment strategies. CASE SUMMARY A 60-year-old male patient presented with a three-day history of nausea, vomiting, upper abdominal pain, and loss of appetite. An upright abdominal X-ray revealed a gas shadow in the intrahepatic and extrahepatic bile ducts. Endoscopy revealed a brown and black stone measuring approximately 3030 mm in diameter in the gastric pylorus, incompletely obstructing the gastric outlet. The diagnosis of Bouveret’s syndrome was accurately confirmed via an abdominal CT scan. Endoscopic removal of the stone was successful, owing to the stone being fragmented and extracted in pieces using a crushing basket. Three weeks later, laparoscopy was attempted but failed because of severe tissue adhesions. Consequently, the procedure was converted to a laparotomy, and fistula repair and cholecystectomy were performed. He returned to the outpatient clinic for follow-up, and no further concerns were noted. CONCLUSION This case highlights the importance of timely diagnosis and adaptable endoscopic and surgical approaches for effectively managing Bouveret’s syndrome.

Multiscale study on the compressive performance of diverse solid waste backfill bodies

To create green, low-energy self-compacting backfill materials, this study utilizes aeolian sand, slag, red mud, and calcium carbide slag to prepare diverse solid waste backfill materials in synergy. Additionally, a suitable amount of polypropylene fibers is added to enhance its toughness. During the experimental process, unconfined compressive strength tests were conducted using digital speckle technique. Computerized tomography scanning technology was employed for internal 3D visualization of the samples. Material strength difference mechanisms were characterized using SEM–EDS and XRD microscopic techniques. Finally, discrete element numerical simulation was utilized for analyzing the evolution of sample failure. The results show that with the increase in calcium carbide slag doping, the specimen UCS increases and then decreases, and when the doping of calcium carbide slag is 14%, the specimen UCS reaches a local maximum of 3.552 MPa; with the increase in the water–solid ratio, the specimen UCS gradually decreases, and when the water–solid ratio is 0.3, the specimen UCS reaches a local minimum of 3.26 MPa. With the increase in calcium slag doping, the mass percentage of calcium element and calcium-silicon ratio in the multi-solid waste matrix first increased and then decreased, and the micro-morphology of the multi-solid waste matrix included lamellar, block, and rod structures; With the increase in the water–solid ratio, the micro-morphology of the multi-solid waste matrix was gradually transformed, and the pore defects between the cementitious materials gradually increased. With the increase in calcium carbide slag doping, the porosity within the unit decreases, and when the doping of calcium carbide slag exceeds 14%, the porosity increases and the compressive strength decreases; with the gradual increase in the water–solid ratio, the porosity within the unit gradually increases, and the number of holes in the specimen reaches a minimum of 208 within the range of the study when the water–solid ratio is 0.24. Digital speckle technique and PFC numerical simulation together elucidate the sample’s failure process and crack evolution mechanism. Initially, the internal voids of the sample are gradually compacted, and crack propagation is slow. As the load increases to the peak, localized deformation and macroscopic crack formation occur in the sample. After the peak load, the sample exhibits significant displacement deformation, and the number of cracks increases significantly. The research findings can provide reference for the design and construction of solid waste backfill pipelines and trenches.

Association of Mobile Stroke Unit Care and Spending, Utilization, and Death in New York City.

Transport by mobile stroke units (MSUs), which provide access to computed tomography scanning and intravenous blood pressure medications and thrombolytics, reduces time to treatment and may improve short-term functional outcomes for patients with acute stroke. The longer-term clinical and financial impacts remain incompletely understood. The aim of the study was to determine whether MSU care is associated with better health, utilization, and spending outcomes for patients with suspected acute stroke. This was a retrospective, observational study of Medicare patients transported by MSUs versus traditional ambulances in New York City, from October 2016 to December 2019. The study included 167 Medicare patients with suspected acute stroke transported by MSU and 2518 propensity score-matched controls. Primary outcomes included length of stay and discharge destination at the index hospitalization, as well as risk of repeat hospitalization, number of emergency department visits, total costs of care, and death at 1 year. Of 167 patients (mean age, 79.9 years; 56.3% women) transported by an MSU for suspected acute stroke, 61.1% had an ischemic stroke/transient ischemic attack, 7.8% had an intracerebral hemorrhage, and 31.1% had a stroke mimic or other diagnosis. Compared with propensity score-matched control patients, MSU patients were significantly more likely to receive tissue-type plasminogen activator (49.9% versus 9.4%; difference, 37.5 percentage points [95% CI, 30.2-45.6]; P<0.001) but experienced similar lengths of stay (5.9 versus 6.7 days, P=0.13) and were similarly likely to be discharged to a skilled nursing facility (15.6% versus 15.1%, P=0.86). At 1 year, MSU patients had a mortality rate of 21.6%, and control patients had a mortality rate of 28.4%, although the difference did not reach statistical significance (difference, 6.8 percentage points [95% CI, -13.3 to 0.3]; P=0.058). They had similar rates of any repeat hospitalization (24% versus 23.2%, P=0.82) and emergency department visits without hospitalization (14% versus 12%, P=0.86), and there were no significant differences in total spending or specific types of spending. In this study of patients presenting with suspected acute stroke in New York City, transport by MSUs, compared with traditional ambulances, was associated with a trend toward a lower mortality rate at 1 year. Prospective trials and replication in other regions are warranted.

Hypothalamic Hamartoma Presenting as Gelastic Epilepsy: When it Goes Unnoticed

A 5-year-old boy presented with episodes of ocular retroversion occurring over the past 4 weeks. Further investigation revealed frequent bilateral epileptiform frontal activity on electroencephalogram and a nodular formation in the hypothalamus on cerebral computed tomography scan. Magnetic resonance imaging characterized the lesion as a hamartoma of the tuber cinereum. After questioning, episodes of unprovoked laughter since the first year of life, consistent with gelastic seizures, were reported. During follow-up, an increase in testicular volume was noted, and a GnRH stimulation test confirmed the diagnosis of central precocious puberty. The boy underwent treatment with antiepileptic drugs and GnRH analogs. Surgical resection of the hamartoma was performed, resulting in cessation of seizures and behavior’s improvement. Hypothalamic hamartomas can present with precocious puberty and gelastic epilepsy. Diagnosis is challenging and often the symptoms go unnoticed for years. Long-term follow-up and multidisciplinary management are essential for optimal patient care and monitoring.

Middle Meningeal Artery Embolization in Chronic Subdural Hematoma in Post Shunted Normal Pressure Hydrocephalus.

Shunted hydrocephalus patients are at an inherent risk of developing chronic subdural hematomas (cSDHs) from overdrainage. The preliminary results of three much-anticipated clinical trials (STEM, EMBOLISE, MAGIC-MT) have recently been presented, showing efficacy of middle meningeal artery embolization (MMA-E) in reducing observational failure and the need for reoperation in non-shunted patients, but the effect of this procedure in shunted patients remains to be further investigated. In this series, we present our institution's experience with MMA-E in shunted normal pressure hydrocephalus patients in comparison to standard of care (=SOC). We compared nine patients with normal pressure hydrocephalus, ventriculoperitoneal shunt, and shunt-induced cSDHs receiving SOC, shunt adjustment with or without burr hole drainage, to seven patients receiving SOC with MMA-E. Hematoma size and age of patients were matched. Patients were followed with serial head computed tomography scans. Symptoms, hematoma size, time to resolution, resolution status, and embolization details were monitored. Six of seven SDH patients receiving MMA-E resolved. One patient showed residual but stable3 mm cSDH after reinitiation of hydrocephalus treatment. The median time to resolution was 139.5 and 89 days for SOC without and with surgery, and 309 or 88 days for SOC without and with surgery plus MMA-E. One MMA-E patient was lost to follow-up and presented more than one year later with decreasing SDH that resolved by post-MMA-E day504. MMA-E in shunt-induced cSDHs has not shown increased resolution speed compared to SOC and liberal use of MMA-E on this cohort may need to be further investigated.

Beyond the Surface: A Multidetector Computer Tomography Scan Investigation into Age and Gender Differences.

Background The identification of an individual after mass calamities poses challenges to experts when bones are fragmented. Dense bones, such as the maxilla, surpass this challenge and remain intact with sinuses even after incineration, thereby making the sinuses an ideal and reliable forensic science tool. No-ninvasive imaging techniques, such as Computed Tomography (CT), can be used to evaluate such cases and help detect fractures and further locate foreign bodies. This study aimed to estimate the dimensions and volumes of the frontal (FS), maxillary (MS), and sphenoidal air sinuses (SS) on CT scans and investigate age- and sex-related differences. Methods CT scans of the paranasal sinuses were acquired from 158 patients ranging in age from 19 to 73 years, and written consent was obtained from all participants. This study was approved by the Institutional Ethical Committee (ethical clearance number IEC 064/2010). All parameters were statistically analyzed using SPSS 20 version and the significance level was set at p&lt;0.05. Results The bilateral anteroposterior length and height of the FS were significantly larger in men than females (p&lt;0.05). The overall dimensions of the MS and SS were substantially greater in males than females (P &lt;0.05). Likewise, the overall volumes of the fFS, MS, and SS were significantly greater in males than females (p&lt;0.05). However, no significant age-related correlation was observed in the dimensions and volumes of the sinuses. Conclusion The results of this study showed that imaging could be a reliable instrument for personal identification in forensic anthropology. Countries that do not allow autopsies may implement this method to clarify the cause of death.

Diffuse cortical atrophy in young males with alcohol dependence

ABSTRACT Background: One of the most common and significant issues associated with alcohol consumption is its consequences, and one of the organs most affected is the brain. Numerous chronic drinkers in their fifth and sixth decades have demonstrated cortical atrophy in radiological examinations; nevertheless, there is little study in the young age range. Aim: To assess the degree of cortical atrophy in young male adults with alcohol dependence compared to those who have no history of alcohol consumption and its correlation with the severity of alcohol dependence. Materials and Methods: This cross-sectional study included a purposive sampling of 30 patients aged 18–45 years, fulfilling the diagnostic criteria of alcohol-dependence syndrome, and having no prior history of brain damage-causing substances other than alcohol. An equal number of age- and sex-matched control subjects were taken who did not have any history of alcohol consumption. Computed tomography (CT) scans were done for both groups. Alcohol Use Disorders Identification Test C (AUDIT-C), Severity of Alcohol Dependence Questionnaire (SADQ), and Global Cortical Atrophy (GCA) scale were applied to measure alcohol dependence and its severity and the degree of cortical atrophy. Results: All 30 male patients who fulfilled the criteria of alcohol dependence showed significant cortical atrophy in CT scans as compared to control subjects. Out of the 30 alcohol-dependence patients, 4 had only frontal lobe atrophy, while 26 patients had diffuse cortical atrophy, among which 19 patients showed frontal lobe predominance. The degree of atrophy and the severity of alcohol dependency also showed a strong association. Conclusion: There is a persistent pattern of neuroradiological evidence of diffuse cortical atrophy with frontal predominance in young people having alcohol dependence with a mean total duration of alcohol consumption of around 21 ± 5.5 years as compared to those who have no history of alcohol consumption.

Exploring 3D Modeling for Enhanced Visualization and Analysis of Pediatric Pelvic Ring Fractures: A Pilot Study

Introduction Pediatric pelvic fractures are high energy injuries that present substantial treatment challenges due to their propensity for plastic deformation, complex fracture patterns, and lack of consensus on surgical indications. There is potential for negative long-term outcomes in patients with residual deformity, but our understanding of acceptable alignment is limited. Plain radiographs and computed tomography (CT) are frequently employed for pre- and post-operative assessment of injury patterns, but are limited to two-dimensional analysis. Three dimensional (3D) modeling offers an opportunity for improved assessment of pelvic anatomy. Methods Two pediatric patients who sustained unstable pelvic ring injuries requiring operative fixation, with both pre- and post-operative CT scans, were identified from an existing IRB-approved trauma database. Utilizing 3D Slicer, 3D segmentations were rendered from DICOM data and specific landmarks were identified to calculate deformity pre- and post-operatively including displacement at the sacroiliac (SI) joints, pubic symphysis, and iliac crest. A modified Keshishyan deformity index was also calculated. Mesh overlay was performed using Autodesk Maya in x, y and z planes to provide visual representation of post-operative changes. Results 3D renderings successfully illustrated complex pelvic fractures in a 9 year old female and 12 year old. Measurements made on 3D models showed similar improvements in diastasis and symmetry to measurements made in standard 2D imaging, but with generally smaller magnitudes. Graphic overlap allow for sophisticated representation of improvement in deformity. Measurements on plain radiographs and 2D CT differed from 3D measurements by anywhere from 0.1 mm to 6.7 mm. Conclusion This proof-of-concept pilot study demonstrates that 3D renderings enhance the ability to measure displacement and deformity in pediatric pelvic trauma for both pre-operative planning and post-operative evaluation. Future applications of this technology include evaluation of pelvic deformity remodeling after trauma in both operative and non-operatively treated pediatric patients.

Effects of Microsatellite Instability on the Clinical and Pathological Characteristics of Colon Cancer and the Diagnostic Accuracy of Preoperative Abdominal CT Scans

Background: Microsatellite-stable (MSS) and microsatellite-instable (MSI) colon cancer (CC) cases have different characteristics. These characteristics may impact the accuracy of abdominal computed tomography (CT) scan examinations in MSI CC. Methods: A retrospective analysis was conducted to examine the effects of MSI CC on patients’ clinical and tumor characteristics. We determined the accuracy of radiological T and N staging compared to pathological T and N staging in CC patients and evaluated the influence of tumor- and patient-related factors on this accuracy. Results: A total of 131 CC patients who had undergone surgical resection were analyzed. Mismatch repair-deficient (dMMR) CC was predominantly found in the right hemicolon (p = 0.023); it was more likely to exhibit moderate (80.8%) or low-grade differentiation (p = 0.01) and had higher rates of mucinous differentiation (p = 0.001). The median neutrophil and platelet counts and C-reactive protein (CRP) levels at diagnosis were significantly higher in patients with dMMR CC (p = 0.022, p = 0.022, and p = 0.018). The depth of invasion influenced the CRP levels in dMMR CC cases (p = 0.015). The abdominal CT exam was accurate regarding the depth of colonic wall invasion in 58.1% and 38.5% of patients with mismatch repair-proficient (pMMR) and dMMR CC, respectively. The assessment of lymph node invasion was accurate in 44.8% of those with pMMR and 50.0% of those with dMMR CC. There was no significant difference in the accuracy in predicting the T and N statuses between the two groups. The accuracy in the determination of the T and N statuses was not affected by the parameters examined. Conclusions: dMMR CC has specific characteristic features. MSI does not affect the accuracy of preoperative abdominal CT.

Assessment of tissue-air ratios in epoxy resin and PMMA phantoms for radiation dosimetry: findings from experimental measurements and Monte Carlo simulations.

This study assesses radiation doses in multi-slice computed tomography (CT) using epoxy resin and PMMA phantoms, focusing on the relationship between TAR (tissue air ratio) and kilovoltage peak (kVp). The research was conducted using a Hitachi Supria 16-slice CT scanner. An epoxy resin phantom was fabricated from commercially available materials, to simulate human tissue. The phantom contained four peripheral inserts and one central insert for dose measurement, with optically stimulated luminescent dosimeters positioned at various depths (2 to 10cm). Monte Carlo simulations were executed using the Geant4 Application for Tomographic Emission toolkit (GATE) to model photon transport, with the x-ray spectrum generated using SpekPy software. A non-linear fitting model was developed to describe the TAR-kVp relationship across different depths for epoxy resin and PMMA. Results indicated that TAR values were higher at low depths (2cm) and decreased with increasing depth, reflecting the x-ray beam's attenuation. For instance, at 80 kVp and 2cm depth, the experimental TAR for PMMA was 1.102 ± 0.011, closely matching the MC simulation value of 1.110 ± 0.036, resulting in a small difference of 0.7%. At a depth of 10cm, the experimental TAR for PMMA decreased to 0.245 ± 0.006, while the MC TAR was 0.248 ± 0.016, with a relative difference of 1.2%. Similar trends were observed for epoxy resin, where the experimental TAR ranged from 1.070 ± 0.014 at 2cm to 0.235 ± 0.009 at 10cm, while MC simulation values ranged from 1.080 ± 0.038 to 0.238 ± 0.017. Bland-Altman analysis confirmed these results, with mean differences of 0.008 for PMMA and 0.006 for epoxy resin, indicating high agreement between the experimental and simulated TAR values. This study highlights the importance of phantom material selection in dose assessment and the implications of TAR in dose correction within the context of diagnostic radiology.

The Use of Coronoid Process as a Free Graft for Condylar Reconstruction in a Patient With Condylar Osteoma: A Condylar Reconstruction Technical Note (Technical Strategy).

Osteoma is a rare, asymptomatic, and slowly growing benign tumor of bone. Upon reviewing the literature, only 21 cases were previously reported in the mandibular condyle. A 19-year-old male patient presented to the Department of Oral and Maxillofacial Surgery of Ain Shams University complaining of hypomobility and facial asymmetry involving the lower jaw. He stated that he was involved in a road traffic accident (RTA) and sustained a traumatic injury to the head a few years ago. Upon examination, it was noticed that the chin deviated to the right side with some discomfort during function. Computed tomography scans revealed the presence of a hyperdense mass medial to the right condylar pole. Condylectomy was carried out using a preauricular approach. A diagnosis of osteoma was confirmed histopathologically. The defect was reconstructed using the coronoid process as an autogenous-free graft.

Leukemic Phase of ALK-Negative Anaplastic Large Cell Lymphoma Presenting as Leukostasis: The First Case Report in Thailand

Anaplastic large cell lymphoma (ALCL) is an aggressive T-cell lymphoma characterized by hallmark cells that are CD30-positive. ALCL is subcategorized as anaplastic lymphoma kinase (ALK)-positive and ALK-negative types. The leukemic phase of ALK-negative ALCL is extremely rare and usually has a poor prognosis. We report the first case of the leukemic phase of ALK-negative ALCL in Thailand. A 60-year-old man presented bilateral cervical lymphadenopathy and night sweats for 6 months. He was admitted to the hospital with acute fever, progressive dyspnea on exertion, severe headache and blurred vision. His complete blood count revealed marked leukocytosis (352.5 x 109/L) with numerous atypical medium- to large-sized mononuclear cells. The results of his laboratory investigations were compatible with spontaneous tumor lysis syndrome and disseminated intravascular coagulation. The flow cytometry analysis from bone marrow aspiration along with histopathologic findings and immunohistochemistry from bone marrow study were consistent with ALK-negative ALCL. The patient was treated with leukapheresis, renal replacement therapy and high-dose dexamethasone. After achieving hemodynamic stability, a computed tomography scan of the brain was performed due to persistent alteration of consciousness. The results showed extensive intracerebral hemorrhage with severe brain edema and tonsillar herniation. Due to this complication, the treatment plan was adjusted to palliative care with supportive treatment after discussion with his family. The patient subsequently passed away from septic shock.