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81.
The value of cross-sectional echocardiography in the diagnosisof tricuspid valve stenosis is not clearly established. We prospectivelystudied by cardiac catheterization 42 consecutive patients,with a mean age of 29 ± 11 years, who exhibited the cross-sectionalechocardiographic features of tricuspid valve stenosis, definedas: diastolic doming of all three tricuspid leaflets and leafletthickening with restrictive motion. To expose occult and amplifyborderline tricuspid diastolic gradients, simultaneous rightatrial and right ventricular pressures were recorded in thebasal state, after incremental infusions of normal saline to200,400,500, 700 or 1000 ml until a mean right atrial pressureof 12 mmHg was achieved, and finally after intravenous administrationof 0.6 mg of atropine. Eighteen patients, Group 1, (43%) exhibitedmean tricuspid diastolic gradients >2mmHg after saline infusion,increasing from a mean of4 ± 2 to 9 ± 3 mmHg,(P <0.001), 14 (33%) having gradients <2mmHg in the basalstate, together with four (10%) increasing from 1.7 ±0.2 to 4.5 ± l.2 mmHg (P <0.01) after provocationwith fluid challenge. In the remaining 24 patients, Group 2,(57%) the mean tricuspid diastolic gradient was <2 mmHg,both at rest and after provocative manoeuvres. We conclude thatthe cross-sectional echocardiographic features of tricuspidvalve stenosis are not a precise indicator of tricuspid valvestenosis. Provocative manoeuvres during haemodynamic studiesare required to expose occult or amplify borderline tricuspiddiastolic gradients in a minority of patients with the cross-sectionalechocardiographic features of tricuspid stenosis.  相似文献   
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Summary The use of three‐dimensional (3D) models of the dentition obtained from cone beam computed tomography (CBCT) is becoming increasingly more popular in dentistry. A recent trend is to replace the traditional dental casts with digital CBCT models for diagnosis, treatment planning and simulation. The accuracy of these models was previously assessed through comparing linear physical and radiographical measurements. However, this assessment technique is both observer and landmark dependent. The accuracy of 3D CBCT teeth reconstructions is yet to be reliably measured. To assess the accuracy of 3D CBCT reconstructions of the teeth using a semi‐automated and observer‐independent method and to assess the influence of field of view (FoV) selection on reconstruction accuracy. Fully dentate upper and lower dry human jaws, placed in a plastic box and immersed in water, were scanned using CBCT with small, medium and large FoV. The teeth were then scanned separately using MicroCT. Cone beam computed tomography and MicroCT 3D teeth models were compared, and mean surface difference was calculated per tooth for each FoV. Mean and (maximum) differences between MicroCT and CBCT were 120 ± 40 (max. 679) μm, 157 ± 39 (max. 824) μ and 207 ± 80 (max. 862) μm for the small, medium and large FoV, respectively. Cone beam computed tomography models were larger than MicroCT because of larger voxel size. Our results indicate that CBCT may provide accurate 3D reconstructions of the teeth that can be useful for some clinical applications.  相似文献   
85.
Unicystic Ameloblastoma (UA) is a rare variant of ameloblastoma which is an odontogenic epithelial neoplasm, typically affecting mandibular ramus. Maxillary ameloblastoma is a rare entity with a more disastrous consequence. Although extremely rare, their highly recurrent and locally aggressive behavior can lead to invasion of vital structures surrounding maxilla (orbit, cranium) even after several years of conservative surgical management (limited resection, curettage). We report a case of 16-year-old girl presenting with proptosis of left eye, UA left maxilla, who was treated initially with limited resection (enucleation) and curettage and the lesion recurred after two years with a more aggressive behavior, causing destruction floor of orbit. To this date there are only 23 documented cases of orbital invasion and only three of the reports are in ophthalmic literature. The ophthalmologists need to be aware of this type of rare lesion presenting as proptosis.  相似文献   
86.

Objectives

The aim of this study was to determine the prevalence of apical periodontitis (AP) detected in cone beam CT (CBCT) images from a database.

Methods

CBCT images of 300 Brazilian patients were assessed. AP images were measured in three dimensions. Age, gender, number and location of total teeth in each patient were considered. AP location was considered according to tooth groups. The extent of AP was determined by the largest diameter in any of the three dimensions. Percentages and the χ2 test were used for statistical analysis.

Results

AP was found in 51.4% of the patients and in 3.4% of the teeth. Higher prevalence of AP was found in 60- to 69-year-olds (73.1%) and in mandibular molars (5.9%) (p < 0.05). Inadequate endodontic treatment presented higher prevalence of AP (78.1%).

Conclusions

AP can be frequently found in CBCT examinations. The presence of AP has a significant association with patients'' age, and tooth type and condition. CBCT databases are useful for cross-sectional studies about AP prevalence in a population.  相似文献   
87.
□ The aim of the study was to obtain perioperative patient‐specific costs associated with orthopaedic anaesthesia □ A prospective observational study design was used to determine fixed, semi‐fixed, and variable costs □ The preliminary results of the first 60 patients reports a mean total perioperative anaesthetic cost of £291 (SD: £103.9, median: £278.09, IQR: £219.3–£369.5) □ Fixed and semi‐fixed costs are a major cost component of anaesthesia; variable costs account for only 12 per cent of total cost □ The results of this study will be used in an economic evaluation examining the use of different anaesthetic techniques in orthopaedics  相似文献   
88.
Patients with the syndrome of chronic daily headache often report migrainous symptoms and consequently are diagnosed as having a primary headache syndrome. We report two cases of idiopathic intracranial hypertension causing chronic daily headache with migrainous features in the absence of associated papilledema.  相似文献   
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Ninety five normal Caucasian subjects (51F, 44 M) aged from 2 to 25 y were measured at the hand and wrist level with a small DXA system (pDEXA™) in order to obtain the normal values of the bone mineral content (BMC), density (BMD) and projected area (A) of carpal (c) and metacarpal (m) bones. BMDc ranged from 0.065 ± 0.007 g/cm to 0.365 ± 0.035 g/cm in females and 0.425 ± 0.040 g/cm in males. It presented a sharp change of increase rate at 15.5 and 17 y of age in girls and boys, respectively. Ac presented the same kind of evolution as BMDc, but had a larger value dispersion. The second metacarpal bone had the highest BMCm value in 85% of females and 90% of males. The sum of BMCmi or Ami values (i = 1–5) and the projected mean density of the 5 metacarpal bones was well correlated with BMCc, Ac and BMDc, respectively ( r > 0.90). A volumetric mineral density, dmi, calculated for each of these bones, approximated to a cylinder, was correlated with age ( r > 0.85).  相似文献   
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