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Feb 2026 DOI 10.14302/issn.2576-6694.jbbs-26-5964
The combination of ultrasonography (US) and cone beam computed tomography (CBCT) has been proposed as a multimodal imaging strategy capable of uniting realtime softtissue assessment with highresolution threedimensional visualization of osseous structures. This study critically evaluated whether such integration provides measurable diagnostic or workflow advantages in mandibular imaging. Despite strong theoretical justification, the combined use of US and CBCT failed to demonstrate clinically meaningful improvements in diagnostic accuracy, confidence, or efficiency when compared with CBCT alone. Fundamental physical mismatches, hardware incompatibilities, geometric constraints, and operatordependent variability limited the anticipated synergistic benefits. These negative findings underscore the importance of reporting unsuccessful integration attempts to guide future research and prevent premature clinical adoption of technically incompatible imaging paradigms.
Mar 2023 DOI 10.14302/issn.2766-8630.jrnm-22-4093
Attenuation differences from 2 x-ray sources allow differentiation and characterization of stone types with similar radiation dose compared to single-energy CT scan. The difference is shown in colours, allowing preoperative prediction and management of stones. We determined the effect of DECT-KUB on urological management of patients with uric acid stones since it was first introduced in our centre. 50 patients with uric acid stones were selected from 2 year groups, each with 25 patients and their urological managements were reviewed retrospectively. We concluded that DECT-KUB is an accurate way of determining the chemical characteristics of renal calculi and can alter patients’ management. It has gained wide acceptance among clinicians in our centre and is now widely used to plan urological management of patients with renal calculi. Based on urological management comparison of patients who presented in the year 2011 with uric acid stones and patients in the year 2020, we concluded that patients with uric acid stones based on DECT-KUB findings can start dissolution therapy instead of surgical extraction or lithotripsy prior to biochemical analysis results become available. Although utility of DECT-KUB is widely accepted among clinicians in our centre it may not be available worldwide and this is the limiting factor in its universal use.
Sep 2022 DOI 10.14302/issn.2692-1537.ijcv-22-4328
Objectives To evaluate the diagnostic accuracy of chest CT for the diagnosis of COVID-19 associated with the clinical presentation and in relation to the PCR-RT. Sensitivity, specificity, positive predictive value and negative predictive value, gender, age group and degree of lung involvement will be evaluated. Methods We evaluated 1545 patients with chest CT, delineating the age range and degree of lung involvement, and 306 patients with chest CT and PCR-RT. Results Of the 1545 examinations, 53% were men and 47% were women, there was greater involvement in the 50-59 age group. In the pulmonary study, 55.05% were COVID-19. In the degree of lung involvement 37.70% were mild, 35.76% were moderate, and 26.54% were severe. In the distribution by age, there was a greater involvement between 50-59 years with 56% between moderate (27.6%) and severe (28.0%). Between tomography and PCR-RT, the sensitivity was 68.8%, specificity 59.5%, accuracy 91.3%, with prevalence 31.9%, positive predictive value 44.3% and negative predictive value 80.3%, in females, sensitivity 55.3%, positive predictive value 37.1%, negative predictive value 75.3%, in males, sensitivity 81.6%, positive predictive value 50, 6 and negative predictive value 86.6%.The sensitivities are different between the genders with p of 0.005 and specificity of 0.938, with age effect, starting at 45 years we have a p of 0.057 that decreases to 0.006 at 80 years for sensitivity and specificity. Conclusions The sensitivity and accuracy of CT scan in relation to PCR-RT was significant. Sensitivity increases with prevalence and in the older age group and in men.
Feb 2021 DOI 10.14302/issn.2766-8630.jrnm-21-3713
Introduction Multislice computed tomography examinations performed 3 to 4 days after the onset of symptoms is the imaging procedure of choice in acute pancreatitis, which is mainly done for evaluating the complications. Due to radiation exposure and cost, alternative scoring systems like Ranson’s score and Glasgow’s score were devised but were cumbersome. The serum amylase and lipase were found to increase with progression of disease. The objective of this study was to evaluate the association of acute pancreatitis by modified CT scoring system with the serum levels of amylase and lipase. Material and Methods In hundred patients presenting with acute pancreatitis, the severity of pancreatitis was recorded using the modified CT severity index. The serum amylase and lipase levels were recorded and correlated with modified CT severity index score. Results Among 100 patients studied, 46%, 40% and 14% had mild, moderate and severe grades of pancreatitis respectively by modified CTSI score. No significant correlation was found between the levels of serum amylase (r = -0.104, p = 0.301) and lipase (r = -0.177, p = 0.079) with the modified CT severity index in patients with acute pancreatitis. Conclusion The serum level of amylase and lipase had non-significant correlation with the modified CT severity index score and thus did not indicate severity of pancreatitis.
Aug 2017 DOI 10.14302/issn.2574-4526.jddd-17-1688
Patients with inflammatory bowel disease (IBD) frequently visit the emergency department (ED). The use of cputed tomography (CT) scans in this population has drastically increased in recent years and may confer an increased risk of malignancy. Records were obtained for IBD patients aged 18 or older who visited our institutional ED with a gastrointestinal chief complaint and who had a CT scan ordered by an ED physician. A predictive model for identifying a clinically actionable finding (CAF) on CT scan was created using logistic regression carried out on a predetermined set of variables. Data were available on 156 Crohn’s disease (CD) patients contributing 350 visits and 63 ulcerative colitis (UC) patients contributing 114 total visits. CAF was identified at 108/350 (30.9%) of visits in CD patients and 33/114 (29.0%) of visits in UC patients. History of CAF (OR 11.6, CI 4.54-29.6) and a platelet count above 400,000/mL (OR 3.42, CI 1.56-7.50) were the strongest predictors of CAF. History of psychiatric illness (OR 0.67, CI 0.35-1.29) and diarrhea (OR .043, CI 0.23-0.83) were associated with a lower likelihood of CAF. A prediction model was created that was able to detect 94.4% of CAF cases while correctly predicting CAF non-cases 35% of the time. This model holds promise as a tool to reduce imaging in this population.
Jan 2017 DOI 10.14302/issn.2470-5020.jnrt-16-1415
Objectives: Computed tomography angiography (CTA) provides early assessment of cerebral vasculature in ED patients presenting with Acute Ischemic Stroke (AIS). Prior studies using 4 row detector CT scanners have suggested that results may be used to determine who receives thrombolytics (tPA). We sought to evaluate the rate of normal CTA and the use of tPA in AIS patients with and without blockages using modern CT technology. Patients and Methods: We conducted a retrospective cohort study of all code stroke patients presenting to our ED over a 3 year period. Inclusion criteria included an ED and neurology diagnosis of AIS with a CTA performed at presentation. All patients had a NIHSS score recorded at presentation and underwent imaging using a 64 row detector scanner with 50cc of non-ionic contrast. Demographic, imaging, and clinical data were collected. Modified Rankin Scores (mRS) were assigned at hospital discharge. Good clinical outcome was defined as a mRS of 0-2. Data are reported as frequencies and medians with interquartile ranges (IQR) as appropriate. Rates of tPA use were evaluated using χ2 testing. Rates of good outcomes were evaluated using odds ratios. Results: A total of 205 subjects met inclusion for analysis of which 103 (50%) were male and 109 (54%) had no blockage on CTA. The median NIHSS score and mortality rates were 14 (IQR 8-19), 14 (14%) with CTA blockage, and 4 (IQR 2-7), 2 (2%) for those without. Of those AIS with a blockage on CTA 46 (48%) were treated with tPA including 29 who were treated with intra-arterial therapy as well while only 13 (13%) of patients without a blockage were treated with tPA. Post tPA bleeding occurred in 12 (13%) patients with blockage on CTA and in 0 patients without blockage. Use of tPA was significantly more frequent in patients with a blockage on CTA, P <0.001. Conclusion: More than half of our AIS patients presenting through our ED have no blockage on CTA. Inter-rater reliability among neuroradiologists evaluating for large vessel occlusion appears to be very good. Patients with AIS and no blockage on CTA have less severe strokes and are less likely to receive tPA. Given the new guidelines recommending endovascular treatment for AIS we expect more emergency departments to begin performing CTA.
Aug 2016 DOI 10.14302/issn.2473-1005.jdoi-16-1167
Context: The present study was undertaken to do a comparative evaluation of the role of Cone Beam Computed Tomography (CBCT) imaging and Orthopantomography (OPG) for pre-operative implant planning in combination with sinus grafting procedures in order to assess sinus anatomy and morphology and the existing bone height in three dimensions. Aims: To assess sinus anatomy and morphology and the existing bone height in three dimensions. Materials and Methods: Pre-operative assessment of maxillary sinuses for implant planning using CBCT imaging was performed on 20 sinuses (17 patients). These patients were subjected to orthopantomographs and CBCT imaging both pre-operatively and post-operatively. CBCT imaging helped to decide the type of sinus augmentation procedure best suited for the patients as per the individual needs and depending on the residual alveolar bone height, timing of implant placement, sinus morphology, anticipation of complication and comparative analysis between pre-and post-procedural gain in vertical alveolar bone height and increase in bone density. Statistical Analysis: The results were tabulated and statistically analyzed using Paired and Unpaired t-tests. Results: In the majority of cases, there was a concordance between the treatment type based on pre-operative and post-operative CBCT scans. The assessment of sinus morphology revealed a significantly higher detection rate of abberations in the form of sinus mucosal hypertrophy and septae on CBCT which were imperceptible on routine radiographs. The most appealing result was that vertical alveolar bone height could be measured precisely and there was a significant increase in surgical confidence and a significantly better prediction of complications when using CBCT imaging. Conclusions: A pre-operative planning based on CBCT imaging seems to improve sinus diagnostics and helps to execute a better treatment plan. Also, it is a good tool for the comparison of vertical alveolar bone height pre-and post-operatively following sinus augmentation procedures using various graft materials.
Feb 2026
Objective The landscape of non-small cell lung cancer (NSCLC) has changed due to liberalized utilization of computed tomography, developments in immunotherapy and targeted treatments, and guidelines encouraging sublobar resections. We analyzed the implications of these advances for surgical procedures over a 16-year period. Methods The National Cancer Database was used to identify NSCLC incident cases from 2004 to 2020. Histology, stage, grade, and treatment were analyzed using descriptive statistics and logistic regression. Results 2,028,553NSCLC patients were identified. Each year was associated with an increase in Stage I for NSCLC (OR1.05, 95%CI 1.05-1.05) and histological subtypes (adenocarcinoma: OR1.03, 95%CI 1.03-1.04; squamous: OR1.02, 95%CI 1.02-1.02; neuroendocrine: OR1.11, 95%CI 1.11-1.12), with no change in adenosquamous histology. A similar increase was observed for well- or moderately-differentiated histology (OR1.04, 95%CI 1.04-1.04). The proportion of patients receiving chemotherapy decreased (OR0.98, 95%CI 0.98-0.98), while more patients were treated with immunotherapy or targeted therapy, including an increase of 14% using immunotherapy or targeted therapy as first-line treatment. There was a decrease in the likelihood of receiving pneumonectomy (OR 0.91, 95%CI 0.91-0.91). Despite guidelines advocating sublobar resections, these procedures only increased by 1.1% per year. Conclusions Over the 16-year study period, there was a significant trend towards diagnosis of Stage I NSCLC. The most pronounced change in treatment patterns has been more patients receiving immunotherapy and less chemotherapy. Despite a promising decrease in pneumonectomies, the frequency of sublobar resections remains stagnant, indicating limited uptage in current practice.
Apr 2020 DOI 10.14302/issn.2372-6601.jhor-20-3293
Objective Meningiomas are most common intracranial benign tumors comprising around one third of all intracranial neoplasms, and typically have benign and indolent nature with slow-growing behaviour. Benign meningiomas are slow growing tumors typically following an indolent disease course. Nevertheless, atypical or anaplastic meningiomas may follow a more aggressive disease course with invasion of critical structures and recurrences. In the current study, we evaluate the incorporation of magnetic resonance imaging (MRI) for radiosurgery treatment planning of atypical meningiomas. Materials and Methods Atypical meningioma radiosurgery target volume determination with and without incorporation of MRI has been evaluated. Ground truth target volume used as the reference has been outlined by the board-certified group of radiation oncologists after comprehensive assessment, thorough collaboration and consensus. Results Target volume definition by use of Computed Tomography (CT)-only imaging and by CT-MR fusion based imaging has been comparatively evaluated in this study for linear accelerator (LINAC)-based radiosurgical management of atypical meningioma. Ground truth target volume defined by the board-certified radiation oncologists after detailed evaluation, collaboration, colleague peer review and consensus has been found to be identical to target determination by use of CT-MR fusion based imaging. Conclusion Despite significant progress in neurosurgical techniques over the years, complete surgical resection may not be feasible in the presence of meningiomas located at eloquent brain areas in close association with important neurovascular structures. RT may have a role in multidisciplinary management of meningiomas. Incorporation of MRI into treatment planning for radiosurgery of atypical meningiomas may improve target definition despite the need for further supporting evidence.
Apr 2019 DOI 10.14302/issn.2998-4211.jalr-19-2658
Alzheimer’s Disease (AD) is one amongst the overwhelming types of dementia that distresses the brain nerve cells leading to a perpetual loss in memory and creating a lot of difficulties for the family members in caretaking. The prediction of the disease at an earlier stage is a common problem. The most prevalent imaging modalities used for diagnosing AD are Magnetic Resonance Imaging (MRI), Positron Emission Tomography (PET) and Single Photon Emission Computed Tomography (SPECT). They can provide valuable information regarding the changes in internal and external brain regions and activities for diagnosing AD. But the relevant studies made on retina reveals that in addition to brain changes there are some variations on the retina layers of the AD patients. Therefore, the retina can be used as a biomarker for diagnosing AD. There are different techniques available for an eye examination. Most noticeable of them are Fundus Imaging and Optical Coherence Tomography (OCT). In this paper, we have focused on OCT retinal images of AD patients for the early diagnosis of AD.
Dec 2018 DOI 10.14302/issn.2574-4526.jddd-18-2521
Introduction: Ultrasound study of locally advanced gastric cancer that has spread to adjoining tissue and lymph nodes. This tumor can be associated with T2 to T4 stages of cancer. A “Locally advanced gastric cancer” is a tumor, which may be categorized as ‘resectable’ cancer when compared with M1 advanced cancer. Objective: The aim of this study was to evaluate the Capabilities of transabdominal ultrasonography in assessment of structures and functional disorders of the locally advanced gastric cancer of diverse localization Materials and Methods: A total of61 patients with locally advanced gastric cancer were analyzed of which 36 (59,0%) were males (mean age 62.7 years) and 25 (41,0%) were females (mean age 59.3 years). All patients were managed surgically and underwent preoperative X-ray, virtual gastroscopy techniques, multidetector computed tomography and transabdominal ultrasonography (USG). Histopathology results found, in 58 (95,1%) cases adenocarcinoma, in 3 (4,9%) – ring-cell carcinoma (cricoidal) gastric cancer was established. Stage T2 was diagnosed in 16 (26.2%) cases, T3 - in 41 (67.2%) cases, T4 - in 4 (6.6%) cases. The stomach tumor in 29 (47.5%) cases was localized mainly in the antrum, 27 (44.3%) – in the body, 5 (8.2%) in the cardia and fundus (Table 1). In 24 (39,3%) cases, pyloric stenos was diagnosed - of which in 6 (9,8%) it was compensated, in 18 (29,5%) - sub compensated. All patients underwent preoperative X-ray, virtual gastroscopy techniques, multidetector computed tomography and transabdominal ultrasonography (USG). Normal ultrasound features were observed in 35 patients without gastric pathology. Ultrasonography was carried out with the convex and micro convex transducers in the frequency range of 2-5 MHz and 4-7 MHz respectively in B and color Doppler modes. Results: The polypoid type of gastric cancer was detected in 3 (4,9±2,8%) cases, the ulcerative type – in 18 (29,5±5,8%), the infiltrative ulcerative type – in 27 (44,3±6,4%) and the diffuse infiltrative type – in 13 (21,3%±5,2%) cases respectively. In 24 (39,3%) cases, pyloric stenos was diagnosed - of which in 6 (9,8%) it was compensated, in 18 (29,5%) – sub compensated. The layers of the gastric wall were not differentiated in all patients with sub compensated pyloric stenos. The gastric wall thickness of the affected area was 10,2±2,9mm in the case compensated pyloric stenosis, the length was 27,1±6,2mm, the diameter of the pylorus was 8,3±0,8mm. Among patients with sub compensated pyloric stenos, the thickness of the gastric wall was 19,8±4,1mm, the length was 43,6±4,5mm, the pyloric diameter was 4,3±1,1mm. Among the 61 patients studied, pathological vascularization was detected in 42 (68.8%) cases. It was observed that, all 4 (6.5%) patients with gastric cancer were stage T4 and 38 (62.3%) were stage T3. Vascularization was weak in 13 cases, in 24 cases - moderate, and in 5 cases - enhanced. Metastases to the regional lymph nodes were diagnosed in 52 cases. Ultrasonographically, they were detected only in 37 (71.2%) cases. Conclusions: In the diagnosis of locally advanced gastric cancer, ultrasonography demonstrates good capabilities for determining the extent and depth of the affected area. Color doppler mode allows the study of vascularisation of a locally thickened area, as well as nearby enlarged lymph nodes, which is very important to ascertain the degree of malignancy of the hyperplastic process. ltrasonography can independently determine the degree of pyloric stenosis in patients with distal gastric cancer.
Jan 2018 DOI 10.14302/issn.2577-2279.ijha-17-1903
The aim of the present study was to compare mandibular neurovascular canal anatomy in human and great apes by using cone beam computed tomography (CBCT). The anatomical variability of mandibular neurovascular canals (mandibular, incisive and lingual canals) of 129 modern humans and great apes (Homo, Pan and Gorilla) were analyzed by linear measurements on CBCT images. The Kruskal-Wallis non-parametric test and Dunn’s all pairs for joint ranks were applied to compare the variability of mandibular canals among these groups. Human, Chimpanzee and Gorilla groups showed significant differences in the dimensions of the mandibular canal, mental foramen, incisive canal, lingual canal and anterior mandibular bone width. Bifid mandibular canals and anterior loops were the anatomical variations most frequently observed in the Gorilla. Humans had a larger mental foramen and a distinctive incisive canal. The latter could not be identified in the Gorilla group. The variability in the anatomy within mandibles of human and non-human primates, shows different forms in the neurovascular structures. In comparison to the mandible of great apes, the incisive canal is suggested to be a feature unique to the human mandible.
Nov 2016 DOI 10.14302/issn.2574-4526.jddd-16-1322
Summary Primary malignant melanoma arising from the parotid gland is extremely rare and only sporadic cases have been described. This entity is characterized by delayed diagnosis, poor prognosis and controversial pathogenesis. We report a case of primary malignant melanoma of the parotid gland in a 54-year-old man. The initial diagnosis, made by fine needle aspiration cytology, was malignant tumor without precision. Radical parotidectomy was performed. Diagnosis of primary melanoma of the parotid gland was confirmed by immunochemical analysis revealing positive staining for S-100, HBA-45 and Melan A. Computed Tomography and whole-body 18F-FDGPET/CT image were made to evaluate metabolic and morphologic characteristics of the primary melanoma, to identify potential systemic metastasis at early stage and to exclude primary melanoma elsewhere in the body. The clinical, pathological, immunohistochemical and the role of combined FDG PET/CT features of this lesion are discussed compared to a literature review.
Nov 2016 DOI 10.14302/issn.2574-4526.jddd-16-1311
Adenosquamous carcinoma of the stomach (ASCS) is extremely rare with less than one hundred cases published in the world literature. It is defined by combined adenocarcima and squamous cells carcinoma of the stomach. ASCS is clinically aggressive and has a poor prognosis, even when discovered at an early stage. This intriguing entity is characterized by non specific symptoms or radiological signs. Integrate 18F-fluorodeoxyglucose positron emission tomography/computed tomography 18F FDG.PET/CT is useful morphologic and functional modalities for evaluating primary tumor, local extend and invasion beyond gastric wall or distant metastatic and eventually for management. Diagnosis of ASCS requires immunohistochemical confirmation. We report a 77-year-old man who was admitted to hospital because of epigastric pain, vomiting and melena since more than a month. Gastroscopy with biopsies had initially suggested gastric squamous cell carcinoma .Thoracic and abdominal computed tomography scan (CT) showed a huge mass in the gastric body, largely necrotic, infiltrating the adjacent structures without metastases. Partial gastrectomy with resection of the proximal 2/3 of the stomach, the spleen, the body and tail of pancreas and the left transverse colon was performed. Immunohistochemical analysis demonstrated ASCS with mixed adenocarcinomatous and squamous cells carcinoma with invasion of gastric lymph nodes. Unfortunately, two months after surgery, a CT of the abdomen revealed diffuse metastasis and the patient died three months later. In light of this case, we discuss the pathogenesis, staging and monitoring of this rare entity by combined 18F-FDG PET/CT with review of the literature.
Sep 2016 DOI 10.14302/issn.2473-1005.jdoi-16-1196
Background and Context: Autologous bone grafts require a second surgical exposure to harvest the graft with a significant risk of post-operative complications and donor site morbidity. Employment of allografts potentially eliminates donor site morbidity but carries the potential of causing foreign body immune reactions with a high rate of rejection and failures. Hence, Alloplasts have emerged as novel materials to overcome the drawbacks of autogenous and allogenous bone grafts. Today’s advanced dentistry is enterprising a putty form of calcium phosphosilicate (CPS) into several aspects of reconstructive domain of dentistry including the sinus augmentation procedures, osseous regeneration of periodontal bone defects, cystic cavity defects and alveolar socket preservation. This eccentric multifaceted study was planned as an honest effort on the path of proving the efficiency of CPS as an alloplastic bioactive graft material and aimed at quantitative evaluation of regenerated bone radiographically using Cone Beam Computed Tomography (CBCT) scans following sinus augmentation procedures. Materials and Methods: A total of 20 sinus augmentations were carried-out in 17 patients satisfying the criteria (inclusion and exclusion) requiring placement of implants in atrophic maxilla and in other situations of anatomic constraints. The graft material used was calcium phosphosilicate (CPS) putty (Nova bone dental putty, Novabone products, Alachua, Fla). The residual bone height was recorded using CBCT scans and a computer based software where the measurements were made from the crest of the ridge till the sinus floor lining. The patients were assessed clinically at immediate post-operative, 1 week, 1 month, 3 months and 6 months follow-up recalls post-operatively. Radiographic assessment for bone height was done pre-operatively and at 6 months follow-up recall post-operatively using Cone Beam Computer Tomography scans. Results: The post-treatment bone height (11.76+0.97mm) was found to be significantly higher than the pre-treatment bone height (6.8 +0.70mm) in indirect sinus augmentation procedures (t=14.4, p<0.005). In case of direct sinus augmentation group also, the post-treatment bone height (11.27 +0.71mm) came-out to be significantly higher than the pre-treatment bone height (2.44 +0.81mm) (t=32.17, p<0.005). The post-treatment bone grafted sinus floor measurements (1107.6 + 155.6mm) were also found to be significantly higher than the original sinus floor measurements of bone density (Grayscale values) (412+ 65.5mm) (t=16.6, p<0.001) in case of indirect sinus augmentation procedures. Similarly, the post-treatment bone grafted sinus floor measurements (1169.6+136.7mm) were found to be significantly higher than the original sinus floor measurements of bone density (Grayscale values) (416.4+ 0.70mm) (t=17.9, p<0.001) in case of direct sinus augmentation group. Conclusion: Calcium Phosphosilicate (CPS) was accepted well at the recipient sites without any complications demonstrating its efficiency and reliability in sinus augmentation procedures.
Feb 2016 DOI 10.14302/issn.2473-1005.jdoi-15-912
A healthy 55-year-old man was referred to the Department of Endodontics, Oral and Dental Healthy Hospital, Eskişehir suffering from pain and paraesthesia in the left lower lip and chin.A panoramic radiograph revealed the presence of broken endodontic instrument beyond the apex of the mandibular left third molar. A cone beam computed tomography (CBCT) examination was undertaken, which revealed that the broken instrument was inside the mandibular canal. Damage to the inferior alveolar nerve (IAN) secondary to extrusion of a broken endodontic instrument was diagnosed. Extraction of the tooth was decided and the patient was prescribed with 1 mg/kg/day prednisone 2 times/day, once-daily regimen, and 150 mg/day pregabalin, two doses per day, monitoring the progress with periodic follow-up visits. One month after the incident, the signs and symptoms were gone. The complete resolution of the paraesthesia and the control of pain achieved in the present case suggest that surgical removal of broken endodontic instrument extruded into the mandibular canal with the use of prednisone and pregabalin is a good option in the management of inferior alveolar nerve injury.