The purpose of this review is to summarize the results of studies on of the association between exposure to dental X-rays and health risk. To perform the systematic review, We searched the PUBMED, EMBASE, and MEDLINE databases for papers published before December 15, 2016. A total of 2 158 studies, excluding duplicate studies, were found. Two reviewers independently evaluated the eligibility of each study. The final 21 studies were selected after application of exclusion criteria. In terms of health outcomes, there were 10 studies about brain tumors, 5 about thyroid cancer, 3 about tumors of head and neck areas, and 3 related to systemic health. In brain tumor studies, the association between dental X-ray exposure and meningioma was statistically significant in 5 of the 7 studies. In 4 of the 5 thyroid-related studies, there was a significant correlation with dental diagnostic X-rays. In studies on head and neck areas, tumors included laryngeal, parotid gland, and salivary gland cancers. There was also a statistically significant correlation between full-mouth X-rays and salivary gland cancer, but not parotid gland cancer. Health outcomes such as leukemia, low birth weight, cataracts, and thumb carcinomas were also reported. In a few studies examining health effects related to dental X-ray exposure, possibly increased risks of meningioma and thyroid cancer were suggested. More studies with a large population and prospective design are needed to elaborate these associations further.
Brain Neoplasms ; Cataract ; Head ; Humans ; Infant, Low Birth Weight ; Infant, Newborn ; Leukemia ; Meningioma ; Neck ; Parotid Gland ; Prospective Studies ; Radiation Exposure ; Radiography ; Radiography, Dental ; Salivary Gland Neoplasms ; Thumb ; Thyroid Neoplasms

The purpose of this review is to summarize the results of studies on of the association between exposure to dental X-rays and health risk. To perform the systematic review, We searched the PUBMED, EMBASE, and MEDLINE databases for papers published before December 15, 2016. A total of 2 158 studies, excluding duplicate studies, were found. Two reviewers independently evaluated the eligibility of each study. The final 21 studies were selected after application of exclusion criteria. In terms of health outcomes, there were 10 studies about brain tumors, 5 about thyroid cancer, 3 about tumors of head and neck areas, and 3 related to systemic health. In brain tumor studies, the association between dental X-ray exposure and meningioma was statistically significant in 5 of the 7 studies. In 4 of the 5 thyroid-related studies, there was a significant correlation with dental diagnostic X-rays. In studies on head and neck areas, tumors included laryngeal, parotid gland, and salivary gland cancers. There was also a statistically significant correlation between full-mouth X-rays and salivary gland cancer, but not parotid gland cancer. Health outcomes such as leukemia, low birth weight, cataracts, and thumb carcinomas were also reported. In a few studies examining health effects related to dental X-ray exposure, possibly increased risks of meningioma and thyroid cancer were suggested. More studies with a large population and prospective design are needed to elaborate these associations further.
Brain Neoplasms ; Cataract ; Head ; Humans ; Infant, Low Birth Weight ; Infant, Newborn ; Leukemia ; Meningioma ; Neck ; Parotid Gland ; Prospective Studies ; Radiation Exposure ; Radiography* ; Radiography, Dental ; Salivary Gland Neoplasms ; Thumb ; Thyroid Neoplasms

OBJECTIVE: To comprehensively analyze the spectrum of imaging features of the primary tumors and metastatic patterns of the Extraskeletal Ewing sarcoma family of tumors (EES) in adults. MATERIALS AND METHODS: We performed a computerized search of our hospital's data-warehouse from 1996 to 2013 using codes for Ewing sarcoma and primitive neuroectodermal tumors as well as the demographic code for > or = 18 years of age. We selected subjects who were histologically confirmed to have Ewing sarcoma of extraskeletal origin. Imaging features of the primary tumor and metastatic disease were evaluated for lesion location, size, enhancement pattern, necrosis, margin, and invasion of adjacent organs. RESULTS: Among the 70 patients (mean age, 35.8 +/- 15.6 years; range, 18-67 years) included in our study, primary tumors of EES occurred in the soft tissue and extremities (n = 20), abdomen and pelvis (n = 18), thorax (n = 14), paravertebral space (n = 8), head and neck (n = 6), and an unknown primary site (n = 4). Most primary tumors manifested as large and bulky soft-tissue masses (mean size, 9.0 cm; range, 1.3-23.0 cm), frequently invading adjacent organs (45.6%) and showed heterogeneous enhancement (73.7%), a well-defined (66.7%) margin, and partial necrosis/cystic degeneration (81.9%). Notably, 29 patients had metastatic disease detected at their initial diagnosis. The most frequent site of metastasis was lymph nodes (75.9%), followed by bone (31.0%), lung (20.7%), abdominal solid organs (13.8%), peritoneum (13.8%), pleura (6.9%), and brain (3.4%). CONCLUSION: Primary tumors of EES can occur anywhere and mostly manifest as large and bulky, soft-tissue masses. Lymph nodes are the most frequent metastasis sites.
Adolescent ; Adult ; Aged ; Asian Continental Ancestry Group ; Bone Neoplasms/*pathology/radiography ; Brain Neoplasms/pathology/radiography ; Female ; Humans ; Lymph Nodes/pathology ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Neoplasm Metastasis ; Neuroectodermal Tumors, Primitive/pathology/radiography ; Positron-Emission Tomography ; Sarcoma, Ewing/*pathology/radiography ; Tomography, X-Ray Computed ; Young Adult

OBJECTIVE: To determine whether histogram values of the normalized apparent diffusion coefficient (nADC) and normalized cerebral blood volume (nCBV) maps obtained in contrast-enhancing lesions detected on immediate post-operative MR imaging can be used to predict the patient response to concurrent chemoradiotherapy (CCRT) with temozolomide (TMZ). MATERIALS AND METHODS: Twenty-four patients with GBM who had shown measurable contrast enhancement on immediate post-operative MR imaging and had subsequently undergone CCRT with TMZ were retrospectively analyzed. The corresponding histogram parameters of nCBV and nADC maps for measurable contrast-enhancing lesions were calculated. Patient groups with progression (n = 11) and non-progression (n = 13) at one year after the operation were identified, and the histogram parameters were compared between the two groups. Receiver operating characteristic (ROC) analysis was used to determine the best cutoff value for predicting progression. Progression-free survival (PFS) was determined with the Kaplan-Meier method and the log-rank test. RESULTS: The 99th percentile of the cumulative nCBV histogram (nCBV C99) on immediate post-operative MR imaging was a significant predictor of one-year progression (p = 0.033). ROC analysis showed that the best cutoff value for predicting progression after CCRT was 5.537 (sensitivity and specificity were 72.7% and 76.9%, respectively). The patients with an nCBV C99 of < 5.537 had a significantly longer PFS than those with an nCBV C99 of ≥ 5.537 (p = 0.026). CONCLUSION: The nCBV C99 from the cumulative histogram analysis of the nCBV from immediate post-operative MR imaging may be feasible for predicting glioblastoma response to CCRT with TMZ.
Adult ; Aged ; Antineoplastic Agents, Alkylating/*therapeutic use ; Brain/pathology/radiography ; Brain Neoplasms/*drug therapy/mortality/radiography ; Chemoradiotherapy ; Dacarbazine/*analogs & derivatives/therapeutic use ; Diffusion Magnetic Resonance Imaging ; Disease Progression ; Disease-Free Survival ; Female ; Glioblastoma/*drug therapy/mortality/radiography ; Humans ; Kaplan-Meier Estimate ; Male ; Middle Aged ; Proportional Hazards Models ; ROC Curve ; Retrospective Studies

A 45-yr-old female patient was admitted with one-month history of headache and progressive left hemiparesis. Brain magnetic resonance imaging (MRI) demonstrated a mass lesion in her right frontal lobe. Her brain tumor was confirmed as a small cell glioblastoma. Her follow-up brain MRI, taken at 8 months after her initial surgery demonstrated tumor recurrence in the right frontal lobe. Contrast-enhanced 7.0T brain magnetic resonance imaging (MRI) was safely performed before surgery and at the time of recurrence. Compared with 1.5T and 3.0T brain MRI, 7.0T MRI showed sharpened images of the brain tumor contexture with detailed anatomical information. The fused images of 7.0T and 1.5T brain MRI taken at the time of recurrence demonstrated no significant discrepancy in the positions of the anterior and the posterior commissures. It is suggested that 7.0T MRI can be safely utilized for better images of the maligant gliomas before and after surgery.
Brain Neoplasms/pathology/*radiography/surgery ; Female ; Frontal Lobe/radiography ; Glioblastoma/pathology/*radiography/surgery ; Humans ; In Situ Hybridization, Fluorescence ; *Magnetic Resonance Imaging ; Middle Aged ; Neoplasm Recurrence, Local ; Receptor, Epidermal Growth Factor/genetics

Wernicke's encephalopathy (WE) caused by thiamine deficiency is an acute neurological disorder. Clinically, the classic triad of WE consists of ophthalmoplegia, ataxia, and mental status changes. Thiamine deficiency is known to occur commonly in chronic alcoholic patients. Sometimes, it can occur in patients after gastrointestinal surgery and in those with malabsorption. In addition, patients undergoing renal dialysis, suffering from hyperemesis gravidarum, receiving total parenteral nutrition (TPN), and being treated with chemotherapeutic agents are also prone to develop thiamine deficiency. Herein, we report two cases of WE that developed following simultaneous 5-fluorouracil (5-FU) chemotherapy and TPN in colon cancer patients which was successfully treated with thiamine administration.
Adult ; Antimetabolites, Antineoplastic/*therapeutic use ; Brain/radiography ; Colonic Neoplasms/*drug therapy ; Fluorouracil/*therapeutic use ; Humans ; Magnetic Resonance Imaging ; Male ; Middle Aged ; Parenteral Nutrition, Total ; Thiamine/therapeutic use ; Vitamin B Complex/therapeutic use ; Wernicke Encephalopathy/*diagnosis/drug therapy

Perfusion is a fundamental biological function that refers to the delivery of oxygen and nutrients to tissue by means of blood flow. Perfusion MRI is sensitive to microvasculature and has been applied in a wide variety of clinical applications, including the classification of tumors, identification of stroke regions, and characterization of other diseases. Perfusion MRI techniques are classified with or without using an exogenous contrast agent. Bolus methods, with injections of a contrast agent, provide better sensitivity with higher spatial resolution, and are therefore more widely used in clinical applications. However, arterial spin-labeling methods provide a unique opportunity to measure cerebral blood flow without requiring an exogenous contrast agent and have better accuracy for quantification. Importantly, MRI-based perfusion measurements are minimally invasive overall, and do not use any radiation and radioisotopes. In this review, we describe the principles and techniques of perfusion MRI. This review summarizes comprehensive updated knowledge on the physical principles and techniques of perfusion MRI.
Arteries/chemistry ; Brain Neoplasms/radiography ; Contrast Media/diagnostic use ; Humans ; Magnetic Resonance Imaging/standards/*trends ; Spin Labels ; Stroke/radiography

We report an extremely rare case of metastatic common bile duct cancer from pulmonary adenocarcinoma presenting as obstructive jaundice. The patient was a 76-year-old male, who presented with generalized weakness and right upper quadrant pain. Plain chest X-ray noted multiple small nodules in both lung fields. Abdominal computed tomography scan showed a stricture of the mid common bile duct along with ductal wall enhancement. Endoscopic retrograde cholangiography revealed a concentric, abrupt narrowing of the mid-common bile duct suggestive of primary bile duct cancer. However, pathology comfirmed metastatic common bile duct cancer arising from pulmonary adenocarcinoma with immunohistochemical study with thyroid transcriptional factor-1 (TTF-1).
Adenocarcinoma/*diagnosis/pathology/radiography ; Aged ; Brain Neoplasms/radiography/secondary ; Bronchoscopy ; Cholangiopancreatography, Endoscopic Retrograde ; Common Bile Duct Neoplasms/*diagnosis/secondary ; DNA-Binding Proteins/metabolism ; Humans ; Immunohistochemistry ; Jaundice, Obstructive/*etiology ; Lung Neoplasms/*diagnosis/pathology/radiography ; Male ; Positron-Emission Tomography ; Tomography, X-Ray Computed

We investigated the safety and clinical applicability of 7.0 Tesla (T) brain magnetic resonance imaging (MRI) in patients with brain tumors. Twenty-four patients with intraaxial or extraaxial brain tumors were enrolled in this study. 7.0T MRIs of T2*-weighted axial and T1-weighted coronal or sagittal images were obtained and compared with 1.5T brain MRIs. The T2*-weighted images from 7.0T brain MRI revealed detailed microvasculature and the internal contents of supratentorial brain tumors better than that of 1.5T brain MRI. For brain tumors located in parasellar areas or areas adjacent to major cerebral vessels, flow-related artifacts were exaggerated in the 7.0T brain MRIs. For brain tumors adjacent to the skull base, susceptibility artifacts in the interfacing areas of the paranasal sinus and skull base hampered the aquisition of detailed images and information on brain tumors in the 7.0T brain MRIs. This study shows that 7.0T brain MRI can provide detailed information on the intratumoral components and margins in supratentorial brain tumors. Further studies are needed to develop refined MRI protocols for better images of brain tumors located in the skull base, parasellar, and adjacent major cerebrovascular structures.
Adult ; Brain Neoplasms/*radiography ; Dizziness/etiology ; Female ; Headache/etiology ; Humans ; Magnetic Resonance Imaging/adverse effects ; Male ; Middle Aged ; Muscle Contraction/radiation effects

Aged, 80 and over ; Brain ; Breast Neoplasms ; complications ; drug therapy ; physiopathology ; radiotherapy ; Cranial Fossa, Posterior ; diagnostic imaging ; physiopathology ; Female ; Humans ; Magnetic Resonance Imaging ; Neoplasm Metastasis ; diagnosis ; radiotherapy ; Ophthalmoplegia ; complications ; diagnosis ; physiopathology ; radiotherapy ; Radiography