computed tomography

Purpose:Accurate patient positioning is crucial in radiation therapy. To fully benefit from the preciseness of proton therapy, image guided patient positioning and verification system is typically utilized in proton therapy. The purpose of this study is to evaluate the inter-observer variability of image alignment using a commercially available patient positioning and verification system in proton therapy. Methods:The VeriSuite patient positioning and verification system (MedCom GmbH, Darmstadt, Germany) provides a six degrees of freedom correction vector by registering two orthogonal x-ray images to digitally reconstructed radiograph (DRR) images that are rendered in real time from the planning computed tomography (CT) images. Six cases of various disease sites, including brain, head & neck, lung, prostate, pelvis, and bladder, were used in this study. For each case, the planning CT images and a daily orthogonal x-ray portal image pair were loaded into the VeriSuite system. The same set of x-ray images and CT images for each case were reviewed and aligned separately by each of the 10 radiation therapist, following the clinical procedure for the corresponding disease site. The resulting correction vectors were then recorded and analyzed. Results:Our study shows that the inter-observer variation (One standard deviation) in image alignment using the VeriSuite system ranged from 1.2 to 2.0 mm for translational correction and from 0.6 to 1.3 degrees for rotational correction for the six cases. The use of fiducial markers for prostate patient alignment achieved the least inter-observer variation while the bladder case produced the largest. Conclusions:Inter-observer variation in image alignment could be relatively large, depending on the complexity of patient anatomy, image alignment approach, and user experience and software limitations. Automatic registration and fiducial markers could potentially be used to align patient more accurately and consistently. To ensure adequate tumor coverage in proton therapy, inter-observer variability in patient alignment should be carefully evaluated and accounted for in patient setup uncertainty analysis and treatment planning margin determination.

Aim: The aim of this study was to determine the sensitivity of the tumor markers and diagnostic methods used in the preoperative period for dermoid cysts, the most common benign neoplasm of the ovary. Material and Methods: 136 patients who were operated for any reason and reported as ovarian dermoid cyst in the Department of Obstetrics and Gynecology, Ankara Atatürk Training and Research Hospital between January 2004 and September 2005 were included in the study. The medical records of the cases were obtained retrospectively from Ankara-Atatürk Training and Research Hospital, HIS, archive files and patient numbers where necessary. Results: In the preoperative period, 119 patients underwent ultrasonographic examination, 33 underwent Computed Tomography, and 17 underwent Magnetic Resonance Imaging.10 of the cases only underwent CT, while 3 of the cases underwent only MRI 22 of them underwent both USG and CT, USG and MRI were performed on 13 cases and only 1 case underwent all three of the imaging methods. Tumor markers were CEA, CA 125, CA 19-9, CA 15-3 and AFP. Conclusions: The reviews of ultrasonography and / or computed tomography and / or magnetic resonance imaging (n = 132) revealed that 103 of the cases were put into operation and the sensitivity of the preoperative screening methods were calculated to be 75.5%. The sensitivity of the tumor marker CA 19-9 was calculated to be 31%.

This report presents an adult patient suffering from sacroiliitis like low back pain, lumbosacral radiculopathy and elbow swelling. Multimodality imaging revealed multiple lytic bone lesions located in supra acetabular iliac bone, sacrum, and distal end of radius. Painful numerous lesions due to the extension to the articular surfaces are not expected for Brown tumors. Less than ten cases with multiple Brown tumor due to primary hyperparathyroidism has been reported. Although Brown tumors are mostly diagnosed incidentally, this case would awake the physicians about rheumatological symptoms in the presentation of Brown tumors. Since Brown tumors are non-touch bone lesions that are expected to regress after parathyroid adenoma removal, it is important to distinguish Brown tumors from the giant cell tumors.

The indications for impacted third molar extraction include the prevention of dental reabsorption on the adjacent tooth. Resorption can be classified as physiological (when deciduous teeth are exfoliated) or pathological (when caused by injury or irritation to the periodontal ligament). Many causes can trigger external root resorption (ERR), the most common cause of which is orthodontic forces. The most common cases of ERR involve impacted third molars which, due to the lack of space for their eruption, generate a greater chance of ERR on the distal portion of the second molar. This pathology is becoming progressively more frequent in clinical dental care. Periapical and panoramic radiographs are used to aid in diagnosis, as is cone beam computed tomography. In cone beam computed tomography scans, radiolucent areas with irregular gaps are detected; these gaps represent a significant loss of dental material. The objectives of this article were to report a case of second molar resorption triggered by an impacted third molar and to perform a review of the literature on the causes of external root resorption. Ideally, this information will aid dental clinicians (and orthodontists in particular) in understanding the features of this pathology so that they may recommend preventive third molar extraction when necessary.

Several articles have discussed mandibular condyle position after bilateral sagittal split osteotomies (BSSO). However, previous studies have sought to establish a relationship between orthognathic surgery and the improvement of temporomandibular joint (TMJ) signs and symptoms. Also, they have been limited to two-dimensional evaluation of condylar position considering only the condylar “sag” or improper inferior seating of the condyle. The purpose of this study was to investigate a relationship between changes in condylar position using three-dimensional computed tomography and the negative clinical impact of BSSO on the temporomandibular joint. 

Mesenteric cysts are rare benign intra-abdominal tumors with an incidence of 1 case per 250,000 hospital admission. This lesion occurs most frequently in women in the reproductive period.The etiology of such cysts remains unknown but several theories regarding their development exist. Most of these lesions present with vague abdominal pain and nausea. Less commonly they will present with bowel obstruction due to external compression. The diagnosis of these tumors is by abdominal ultrasound or computed tomography. We report a case of Mesenteric cyst in 51-year-old female patient.

Deliveries prior to 28 weeks’ gestation (extreme preterm birth) pose a global health concern, according to the World Health Organization (WHO). Extreme preterm birth is associated with several complications in the newborn and management in neonatal intensive care unit would incur high expenses. In parallel, advancements in in vitro fertilization will give an opportunity for women to conceive in cases of ovarian failure. At the same time, health providers also encourage patients to receive more than one embryo simultaneously during an embryo transfer. Here we report a case of a patient in coma condition of triplet pregnancy, post ovum donation with three-embryo transfer. Following stabilization, cranial computed tomography (CCT) was performed. The result showed bleeding in the brainstem and into intraventricular spaces at 25+4 gestation weeks. Furthermore, ICH during pregnancy is considered as a rare case in obstetrical field, especially involving the brainstem. This could lead to life-threatening conditions and serious disability in the future. On the fifth day of hospitalization, she suffered from pneumonia and pulmonary edema. On the eight day (26+5 gestations weeks), an emergency caesarean section was performed due to fully dilated of the cervix with breech presentation of all fetuses. Mother and the children survived with some non-life-threatening disabilities. This is the very first case reported of intracerebral hemorrhage in the brainstem in triplet pregnancy after receiving ovum donation. Heterologous conception could be an iceberg phenomenon of gestational complications among the population. Reproductive tourism could still become greater in the future. 

Background: The aim of the study was to evaluate radiographic features of systemic sclerosis-associated interstitial lung disease. Patients and methods: 116 patients with systemic sclerosis-associated interstitial lung disease (SSc-ILD) from 2010 to 2019 comprised our retrospective study. All patients were subject to high resolution computed tomography (HRCT). ILD patterns were classified into 7 patterns as IIPs and analyzed with pathology. We chose two staging method and two semi-quantitative score methods to evaluate the HRCT performance and analyzed with pulmonary function tests. Results: Ground-glass opacities were the most common presentation on HRCT, followed by interlobular septal thickening, reticular opacities, intralobular interstitial thickening; honeycombing, traction bronchiectasis and nodules can also be observed. The most common pattern of SSc-ILD was nonspecific interstitial pneumonia (NSIP), secondly was UIP. There was no difference in ILD pattern between HRCT and pathology, and revealed a high congruence. The four HRCT evaluating methods presented in this study all had significant relationships with PETs. Conclusion: The most common pattern of SSc-ILD was nonspecific interstitial pneumonia (NSIP). The ILD patterns of HRCT coincide very well with histology, and will replace pathology as the gold standard for diagnosis and evaluation of SSc-ILD.

The RNA interference (RNAi) technique is a new modality for cancer therapy, and several candidates are being tested clinically. Nanotheranostics is a rapidly growing field combining disease diagnosis and therapy, which ultimately may add in the development of ‘personalized medicine’. Technologies on theranostic nanomedicines has been discussed. We designed and developed bioresponsive and fluorescent hyaluronic acid-iodixanol nanogels (HAI-NGs) for targeted X-ray computed tomography (CT) imaging and chemotherapy of MCF-7 human breast tumors. HAI-NGs were obtained with a small size of ca. 90 nm, bright green fluorescence and high serum stability from hyaluronic acid-cystamine-tetrazole and reductively degradable polyiodixanol-methacrylate via nanoprecipitation and a photo-click crosslinking reaction. This chapter presents an over view of the current status of translating the RNAi cancer therapeutics in the clinic, a brief description of the biological barriers in drug delivery, and the roles of imaging in aspects of administration route, systemic circulation, and cellular barriers for the clinical translation of RNAi cancer therapeutics, and with partial content for discussing the safety concerns. Finally, we focus on imaging-guided delivery of RNAi therapeutics in preclinical development, including the basic principles of different imaging modalities, and their advantages and limitations for biological imaging. With growing number of RNAi therapeutics entering the clinic, various imaging methods will play an important role in facilitating the translation of RNAi cancer therapeutics from bench to bedside.

Introduction: Desmoplastic Malignant Mesothelioma (DMM) is a rare histological subtype of sarcomatoid malignant mesothelioma arising most frequently in the pleura or peritoneum and less frequently in the lung parenchyma. Patient concerns: A 52-year-old female with no apparent asbestos exposure was referred for consultation in our center after 1 month of cough and no concomitant symptoms of chest. Diagnosis: Chest computed Tomography (CT) revealed a localized mass measuring 4.5 x 3.9 cm in the right lung middle lobe with inhomogeneous enhancement following injection of contrast, and without pleural lesions, considered a primary intrapulmonary desmoplastic mesothelioma. Interventions: Surgical intervention was performed. Outcomes: Following complete tumor resection, the patient declined to receive chemotherapy or radiotherapy. The final diagnosis of intrapulmonary desmoplastic mesothelioma was confirmed by pathological and immunohistochemical examination. In addition, no local tumor recurrence was observed within 10 months of follow-up. Conclusion: Even elderly female patients with localized pulmonary masses without significant pleural lesions should not excluded the possibility of malignant mesothelioma in the lungs.

A previously healthy 26-year-old gentleman, referred from a state hospital with history of alleged fall from 10 feet height at a construction site on the same day. Glasgow coma scale (GCS) at that hospital was E2 V2 M5. He was brought in to our Emergency Unit, Hospital Kuala Lumpur with GCS of E1 V2 M4 (7/15). Pupils were 5mm+ /3mm+. He sustained left ear bleed. Otherwise vital signs were stable, with no other extracranial injury. Computed tomography (CT) scan brain (Figure 1) showed right frontotemporal acute subdural hematoma with left frontotemporoparietal acute subdural hematoma, with underlying subarachnoid hemorrhage, mass effect and midline shift to left side more than 0.5cm and obliteration of basal cistern. 

Asthma is a chronic respiratory disease characterized by chronic airway inflammation. Common manifestations of asthma include wheezing, chest tightness, cough, shortness of breath. Diagnosis of asthma requires clinical documentation of respiratory symptoms, exacerbation of symptoms following exposure to triggers, as well as demonstration of expiratory airflow obstruction. Wheeze is a continuous sound, lasting longer than 0.25 s that is produced by oscillation of opposing airway walls [1,2]. Wheezing, although a typical symptom of asthma, can also be caused by other diseases. Apart from asthma, wheezing can be due to extra-thoracic upper airway obstruction, intrathoracic upper airway obstruction, lower airway obstruction. Benign multimodal goiter is a common disease, that rarely causes upper airway obstruction. Retrosternal goiter should be taken into account the differential diagnosis of upper airway obstruction [3]. The respiratory symptoms of a retrosternal goiter may be masked for years due to the slow growth of the goiter. Patients commonly complain of respiratory symptoms if tracheal diameter is narrowed more than 50% from the normal size. Respiratory symptoms may be suddenly precipitated by spontaneous or traumatically induced bleeding into the substernal goiter, as well as by tracheal infections [4]. Clinical management of this condition is really challenging. Diagnosis is also not straightforward, as clinical suspicion is needed. There are cases of retrosternal goiter mimicking asthma that remain undiagnosed for many years. Retrosternal goiter should be taken into account in the differential diagnosis of patients diagnosed as suffering from asthma, and presenting no improvement despite medical therapy. In addition, it should be taken into account that sudden gland enlargement due to hormonal changes might lead to life threatening upper airway obstruction with clinical picture similar to bronchial asthma attack [5]. In a recent very interesting case report, the authors present a case of a pregnant woman in the second trimester who presented with an acute airway obstruction due to the enlargement of a retrosternal goiter [3]. Goiters are the more common masses of the superior mediastinum [6,7]. Commonly, retrosternal goiter is due to the extension in the thorax of a cervical goiter. However, rarely, it may represent primary disease due to the growth of ectopic thyroid tissue. In addition, retrosternal goiter may develop in patient submitted to thyroidectomy due to cervical multinodular goiter [8]. Although retrosternal goiters are commonly asymptomatic, symptoms may include dyspnea, stridor, hoarseness, dysphagia, superior vena cava syndrome, transient ischemic attacks, cerebral edema, Horner’s syndrome, and thyrotoxicosis [4]. Diagnosis could be verified by neck and chest radiography, thorax CT and MRI. Chest radiography commonly shows a widened mediastinum with a superior mediastinal mass causing compression of the trachea as well as deviation of the trachea to the right. Mediastinal computed tomography reveals a mass that is extension of the thyroid gland. The presence of respiratory symptoms in a patient with retrosternal goiter is an indication for surgery. The majority of retrosternal goiters can be approached through a cervical approach [9,10].

Septic Iliac vein thrombophlebitis with associated psoas abscess is a rare and severe entity, which diagnosis is challenging when no risk factor is clearly present. We are presenting a case of severe septic cavitary pulmonary emboli complicated with Acute Respiratory Distress Syndrome (ARDS) that evolved rapidly to respiratory distress and multi organ failure. A 61-year-old Hispanic male, had multiple emergency department visits due to back pain, being most of them intramuscular pain medications and steroids. In the history, he had back pain that worsened accompanied by poor mobility, generalized malaise, fever and chills. Computed tomography (CT) scan showed a paravertebral psoas abscess with L5 - S1 diskitis/spondylitis inflammatory changes, which was then later evidenced by a gallium study. Further imaging studies were done, showed bilateral cavitary lung lesions, consistent with septic emboli. Subsequent blood cultures were positive for Methicillin Resistant Staphylococcus Aureus (MRSA), for which a successful combined therapeutic regimen was used. Transthoracic and transesophageal echocardiogram were not suggestive of endocarditis. Staphylococcus aureus (SA) bacteremia is one of the most common serious bacterial infections with a high risk of metastatic complications, which makes this pathogen a unique one. The combination of factors iliac vein thrombophlebitis, psoas muscle abscess, diskitis/spondylitis with ARDS makes cavitary pulmonary disease a challenging perspective. After a 6-week antimicrobial treatment, full anticoagulation, his clinical condition and image findings improved, and he was recently admitted for physical rehabilitation. Major vessels thrombophlebitis should always be considered, when primary source of septic pulmonary emboli is not clear. This case illustrates the complexity of illness and complications that may arise from a source of infection as the one in this patient. Further therapeutic strategies were tailored accordingly.

Introduction: Carotid space is a deep neck space within the carotid sheath. .Mosher called carotid sheath as the Lincoln Highway of the neck. Abscess in this space is rare to be seen by young Ear, Nose and Throat (ENT) surgeons in this era of early diagnosis and good antibiotics. We are reporting a case of isolated carotid space abscess in a 20 year old male to familiarize young surgeons with this abscess. Case report: A 20 year old young boy came to our Outpatient Department (OPD) with complaints of fever, painful neck swelling, progressive difficulty in swallowing from the last 7 days. Contrast Enhanced Computed Tomography (CECT) was done which revealed abscess located adjacent to carotid artery in the carotid sheath. Incision and drainage was done and carotid sheath was opened and pus drained .Patient was discharged after few days on oral antibiotics. Conclusion: Carotid space abscesses are rarely seen in developed countries. Tender and fluctuating swelling over the carotid artery area points towards it. CECT is the investigation of choice. Needle aspiration should be avoided especially by less trained persons. Small abscesses may respond to intravenous antibiotics but when frank and large abscess is formed, incision and drainage is the treatment of choice.

Taurodontism is a rare dental anomaly presented with an aberration of teeth that lacks the constriction at the level of the cemento-enamel junction (CEJ). It is characterized by elongated pulp chambers and apical displacement of bifurcation or trifurcation of the roots, forming a rectangular shape. Whilst, it appears most frequently as an isolated anomaly, its association with several syndromes and abnormalities has also been reported in the literature. Although permanent molars are most commonly affected, this anomaly could also be seen in deciduous dentition, unilaterally or bilaterally, and in any combination of teeth or quadrants. These morphological anomalies pose various challenges to the dentist during their endodontic treatment. Modern diagnostic tools such as Cone beam computed tomography (CBCT), loupes and Dental operating microscopes (DOM) help in achieving better treatment outcome in such cases. The presented article elaborates diagnosis and successful management of 2 rare cases of taurodontism in permanent molars.

Fibrous dysplasia is an osteolytic lesion in which bone is replaced by an instable fibrous osseous tissue. The aim of this case report is to highlight dental rehabilitation (bone grafts to allow dental implant) on patients suffering of this condition. A 39-year-old female with a hard-traumatic event in childhood desired a dental implant rehabilitation on her teeth 19 and 30 after an orthodontic alignment. A Cone-Beam Computed Tomography (CBCT) was performed showing a massive radiopaque lesion of the anterior mandible. The bone grafts and dental implants were successfully managed. A non-invasive treatment with regular follow up was chosen for this case. No evolution was noticed twenty-four month later at the follow up CBCT.

Introduction: In endodontically treated teeth, dentinal defects such as microcracks can progress to a vertical root fracture and lead to tooth loss. Objective: The present study aimed to evaluate, by micro-computed tomography analysis, the formation of dentinal microcracks during filling removal in endodontic retreatment of root canals filled with gutta-percha and Total Fill BC bioceramic sealer. Methods: Twenty mesial roots of mandibular molars were instrumented and obturated with gutta-percha and Total Fill BC sealer and then the filling material was removed with rotary Protaper Retreatment files. The specimens were scanned before instrumentation, after filling and after retreatment. The transversal images obtained after filling were compared with the images obtained after removal of the filling material. A descriptive statistical analysis was performed. Results: Among the 24.444 cross-sections analyzed, 5.67% presented some type of dentinal defect, with 0.51% in the initial images, 2.58% in the post-filling images and 2.58% in the post-retreatment images. All the dentinal defects identified in the images obtained after the retreatment were already present in the corresponding images after the filling. New dentinal microcracks were not observed after removal of the filling material. Conclusion: Retreatment of mesial roots of mandibular molars filled with a silicate-based root canal filling material do not influence the formation of dentinal microcracks.

Introduction: COVID-19 is an infectious disease caused by the severe acute respiratory syndrome coronavirus 2 and it was first reported in China. The aim of this study was to compare clinical features, chest CT findings and laboratory examinations of suspected COVID-19 inpatients according to RT-PCR analysis. Methods: Demographics, comorbidites, symptoms and signs, laboratory results and chest CT findings were compared between positive and negative groups. The study included 292 patients (134 females, 158 males) suspected of COVID-19. All statistical calculations were performed with SPSS 23.0. Results: 158 (54.1%) of the cases were male and 134 (45.9%) were female. Their ages ranged from 17 to 95 years, with an average of 50.46 ± 20.87. A symptom or sign was detected in 86.3% of all patients. The chest CT images of 278 patients were analyzed. Chest CT was negative in 59.2% of patients with positive RT-PCR and 43.9% of patients with negative RT-PCR results. Chest CT findings were atypical or indeterminate in 22.4% of patients with positive RT-PCR results and 20% of patients with negative RT-PCR analysis. ALP, bilirubine, CRP, eosinophil count, glucose, CK-MB mass and lactate were significantly lower in patients with positive RT-PCR test. LDH, lipase, MCV, monocyte, neutrophil count, NLR, platelet, pO2, pro-BNP, procalcitonin, INR, prothrombin time, sodium, troponin T, urea, WBC were significantly lower in patients with positive RT-PCR test results. Conclusion: The diagnosis of COVID-19 is based on history of patient, typical symptoms or clinical findings. Chest CT, RT-PCR and laboratory abnormalities make the diagnosis of disease stronger.

Introduction: Laparoscopic approach is emerging as a standard of care approach for management of masses amenable to partial nephrectomy. Laparoscopic partial nephrectomy is a challenging surgery and its successful performance depends on various factors. We aim to evaluate the influence of tumor characterestics on the operative performance for laparoscopic partial nephrectomy. Methods: Patients undergoing laparoscopic partial nephrectomy in our institution were recruited for this study. The tumor profile was evaluated by a senior radiologist from cross sectional imaging (computed tomography or magnetic resonance imaging). Tumor characerestics was defined by assessing tumor size, tumor location and RENAL score. The operative performance was evaluated in terms of warm ischemia time, blood loss, operation duration and any significant operative complications. Statistical inference was drawn. Results: 37 patients who underwent laparoscopic partial nephrectomy between January 2010 and June 2012 were included in this study. The mean tumor dimension was 3.81 cms. 21 tumors involved left kidney and 16 involved right kidney. 12 were located in upper pole, 8 were located in midpole and 17 were located in lower pole. The average RENAL score was 6.56. The mean warm ischemia time, blood loss and operation duration was 26.29 minutes (min), 256.76 millilitres (ml) and 208.11 min respectively. Statistically significant correlation was appreciated between tumor location (polar location, side, anterior/ posterior location) and RENAL score and operative parameters (warm ischemia time and operation duration). Tumor size did not have any correlation with the operative parameters. Conclusion: The operative performance of laparoscopic partial nephrectomy is significantly influenced by the tumor location and RENAL score.

Introduction: Fractures of both the anterior and posterior pelvic ring are common injuries in polytrauma and the elderly that extend beyond those of simple low-impact trauma. While conventional X-rays predominantly show the ventral aspect of the injury, computed tomography often detect additional fractures of the sacrum. A large number of these fractures are B-injuries by AO, mainly compression fractures at an advanced age. In addition, the prevalence of pelvic insufficiency fractures caused by osteoporosis rather than subsequent to an obvious trauma is increasing, with such an injury often associated with pain that impairs mobilization. The standard sacroiliac screw fixation is often characterized by loosening and thus failure of the osteosynthesis especially in osteoporotic bone of elderly patients. Method: A new alternative surgical minimal invasive technique, the “iliosacral bridging”, stabilizes the fractures of the sacrum with an internal fixation from S1 pedicle of the uninjured side to the ilium on the affected side. The combination of this internal fixation with the standard single sacroiliac screw on the injured side allows an immediate full weight bearing and pain free mobilization. We present a case series of 8 patients. Results: The clinical and radiological analysis analogous to the pelvic-outcome-score brought forward that 2 patients showed an excellent and 2 patient a good result. The other 4 patients achieved sufficient results. Conclusions: The “iliosacral bridging” we have introduced in the present study provides evidence of an expected increased stability of the pelvis after B-injuries