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21.
Objectives:To set age-specific normal reference values for brainstem, cerebellar vermis, and peduncles measurements and characterize values’ variations according to gender, age, and age by gender interaction.Methods:565 normal brain magnetic resonance examinations with normal anatomy and signal intensity of the supra- and infratentorial structures were categorized into six age groups (infant, child, adolescent, young adult, middle-age adult, and old aged adults). Patients with congenital malformations, gross pathology of the supra- or infratentorial brain, brain volume loss, developmental delay, metabolic disorders, and neuropsychological disorders (n = 2.839) were excluded. On midsagittal T1 weighted and axial T2 weighted images specific linear diameters and ratios of the brainstem, cerebellar vermis, and peduncles were attained. Two observers assessed a random sample of 100 subjects to evaluate the inter- and intraobserver reproducibility. Intraclass correlation coefficients, means ± standard deviation, one and two-way analysis of variance tests were used in the statistical analysis.Results:Good to excellent inter- and intraobserver measurements’ reproducibility were observed, except for the transverse diameter of the midbrain, the anteroposterior diameter of the medulla oblongata at the pontomedullary and cervicomedullary junctions, cerebellar vermis anteroposterior diameter, and thickness of the superior cerebellar peduncle. Age-specific mean values of the investigated measurements were established. A significant gender-related variation was recorded in the anteroposterior diameter of the basis pontis (p = 0.044), the anteroposterior diameter of the medulla oblongata at the cervicomedullary junction (p = 0.044), and cerebellar vermis height (p = 0.018). A significant age-related change was detected in all measurements except the tectal ratio. Age by gender interaction had a statistically significant effect on the tectal ratio, inferior, and middle cerebellar peduncles’ thickness (p = 0.001, 0.022, and 0.028, respectively).Conclusion:This study provides age-specific normal mean values for various linear dimensions and ratios of the posterior fossa structures with documentation of measurements’ variability according to gender, age, and their interaction.Advances in knowledge:It provides a valuable reference in the clinical practice for easier differentiation between physiological and pathological conditions of the posterior fossa structures especially various neurodegenerative diseases and congenital anomalies.  相似文献   
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ABSTRACT

Objective: To assess the prevalence of temporomandibular disorders (TMDs) and posterior crossbite and/or deep bite and any possible association between them.

Methods: One thousand-nineteen adolescents responded to a questionnaire regarding oral habits and TMD symptoms. Afterwards, they were diagnosed according to the Axis I of the DC/TMD and underwent a dental examination. The chi-square test was used for statistical analysis.

Results: A significant association was found between posterior crossbite and some TMD diagnosis, but no association was found between deep bite and TMD, nor between occlusal diagnosis and bruxism. TMDs were more prevalent in girls. There was a significant sex difference (more among females) in the prevalence of painful TMDs.

Conclusion: Posterior crossbite in the adolescent population analyzed may be related to TMDs, in contrary to deep-bite. The presence of posterior crossbite may have different impact on TMD findings between the sexes.  相似文献   
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ObjectivesTo compare the amount of en-masse retraction with or without piezocision corticotomy, to assess the type of tooth movement, to evaluate root integrity after retraction, and to record reported pain levels.Materials and MethodsThis randomized, controlled clinical trial included 26 orthodontic patients requiring premolar extraction. The patients were divided into two groups: (1) an extraction with piezocision corticotomy group (PCG) and (2) an extraction-only group, which served as the control group (CG). Cone-beam computed tomography images were acquired before and 4 months after the initiation of en-masse retraction utilizing miniscrews. The following variables were assessed: the amount of en-masse retraction, incisor inclination, incisor and canine root resorption, and patient-reported pain.ResultsTwelve and 11 participants completed the entire study in the PCG and CG, respectively. The amount of en-masse retraction was significantly greater in the PCG compared to the CG (mean = 4.8 ± 0.57 mm vs 2.4 ± 0.33 mm, respectively [P < .001]). There was also significantly less tipping and root resorption of incisors in the PCG (P < .05). The reported pain was significantly higher on the first day in the PCG compared to the CG (P < .001); however, it became similar between the groups after 24 hours.ConclusionsPiezocision corticotomy enhanced the amount of en-masse retraction two times more with less root resorption. However, future studies are required to assess the long-term effects of this technique.  相似文献   
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Large bowel obstruction is a rare complication of gastrointestinal endometriosis. A 32-year-old female patient presented to the emergency department with complaints of diffuse abdominal pain and constipation for 10 days with progressive abdominal distention and vomiting. Plain abdominal x-ray showed grossly dilated large bowel up to the sigmoid colon with no gas in the rectum. Abdominal computed tomography revealed hugely dilated large bowel up to the sigmoid colon, with sigmoid soft tissue mass. Flexible sigmoidoscopy showed a non-ulcerating sigmoid mass, with complete obstruction of the sigmoid colon, which impeded the further advancement of the scope. She underwent exploratory laparotomy with provisional diagnosis of complete large bowel obstruction due to sigmoid tumor. Sigmiodectomy with end colostomy was performed. Histopathology revealed endometrial glands with stroma in muscularis properia of the sigmoid colon mass. Endometriosis should be considered in women of reproductive age presenting with symptoms of large bowel obstruction.Endometriosis is the presence of functional endometrial tissue outside the uterus, which affects up to 15% of childbearing age woman.1 It is an uncommon cause of large bowel obstruction.2 If large bowel obstruction occurs, it may be caused by luminal compression from a pelvic organ endometrioma, a fibrotic reaction resulting in stricture and adhesions, or swelling of endometriotic implants in the intestinal wall or a combination of these 3 mechanisms.3 Herein, a rare case of complete large bowel obstruction due to sigmoid colon endometriotic mass is presented in which the treatment was sigmoidectomy with end colostomy. A brief review of the literature pertaining to this condition is also presented. Our objective in presenting this case is to increase the awareness of physicians to the possibility of endometriosis as a differential diagnosis when assessing females of reproductive age who present with manifestations of intestinal obstruction.  相似文献   
28.

Objectives:

To explore the spectrum of pathologies diagnosed in prostatic biopsies of Saudi men, and test whether the frequency of diagnosing the malignant fraction has been changed over the last 15 years, and assess the association between chronic inflammation (CI) with both benign prostatic hyperplasia (BPH) and cancer (PCa), and investigate the histological findings of cases presented with acute urinary retention (AUR) clinically.

Methods:

This is a retrospective cohort study including all prostatic biopsies accessed in the files in the Surgical Pathology Laboratory of King Fahd University Hospital, Alkhobar, Kingdom of Saudi Arabia over 15 years (1999-2013) for Saudi men. Age, procedure indication, and final diagnoses were retrieved and slides were reviewed.

Results:

There were 360 cases included in this study with a median age of 65 year-old. The BPH comprised the most (64.7%), while PCa accounted for 89 cases, 13.5% of which were incidental. Most cases of both BPH and PCa were diagnosed in the seventh decade. The frequency of diagnosing PCa did not show a solid rise or fall over time. Chronic inflammation is more related to BPH than to PCa. Only CI showed a significant statistical association with AUR.

Conclusion:

Prostatic diseases show a stable trend over time. While CI is a common dominator for both BPH and PCa, it is associated more with BPH. Among all histological findings, only CI is related to the clinical presentation of AUR.The spectrum of prostatic diseases is a common health concern all over the world. While benign prostatic hyperplasia (BPH) is the most frequent urologic diagnosis in elderly males worldwide, affecting approximately one third of males in their 60’s,1,2 prostatic carcinoma (PCa) is the second most common cause of cancer-related death in males after lung cancer.3 The disease represents clear racial and national differences, with its highest incidence in blacks in the West, and lowest in Asian males.4 Recently, there has been a rising trend for PCa in populations that are thought to be of low risk.5 Furthermore, the relationship between chronic inflammation (CI) and presence and progression of both BPH and PCa is controversial.6-9 On the other hand, acute urinary retention (AUR), which is the most frequent emergency in urology, is mostly developed in a background of BPH.10 Whether other pathologies, such as CI and infarction increase the risk of this complication is debated.11-13 In this work, we retrospectively reviewed the whole spectrum of prostatic pathologies diagnosed in our center during the last 15 years, including prostatic intraepithelial neoplasia (PIN) and atypical small acinar proliferation (ASAP), and study various diseases in relation to age of diagnosis, explore the change in trend of diagnosing PCa over a period witness an increase in screening and gradual westernization of lifestyle, test the relationship between CI and both BPH and PCa, and also, we investigate the role of different biopsy findings in relation to the clinical presentation with AUR.  相似文献   
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