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21.
Bone mineral “density” (BMD) measured by dual-energy X-ray absorptiometry (DEXA) does not represent the volumetric density (grams per cubic centimeter), but rather the areal density (grams per square centimeter). This distinction is important during growth. The purpose of this study was to measure vertebral dimensions in cadavers of young pigtail macaques (Macaca nemestrina), and to derive equations to predict the volumetric bone density from noninvasive measurements. We measured the areal bone density by DEXA, vertebral volume by underwater weighing, mineral content by ashing, dimensions of lumbar vertebrae by calipers, and dimensions of vertebrae by radiography. Somatometric measurements of the female lumbar vertebral bodies showed that the shape changed during growth. The bone mineral content from the densitometer correlated significantly with the ash weight (r = 0.99, error 8.7%). The correlation coefficient between the volumetric bone mineral density and areal BMD measurement was significant (r = 0.68, p < 0.0001) with a 9.5% error; this improved significantly to 0.82 (7.2% error) when the BMD was divided by the vertebral depth from the radiograph. Areal BMD showed a strong correlation with age (r = 0.82, p < 0.0001), with an average increase of 7.4%/year. In contrast, volumetric mineral density showed a weak relationship with age (r = 0.43, p < 0.01), for an average increase of 1.5%/year. When studying bone mineral density during growth, the differences between volumetric and areal bone mineral density should be taken into consideration. ( 相似文献
22.
Summary We observed a rare cerebrovascular anomaly in a patient with brain-stem infarction. Two right vertebral arteries arose from the subclavian artery and communicated directly with each other under the transverse foramen of the fourth cervical vertebra. The left vertebral artery consisted of a rudimentary artery that arose from the left subclavian artery, ran through the transverse foramen of the sixth cervical vertebra and then tapered down to disappear at the fourth/fifth cervical vertebrae, plus a second, accessory artery that arose from a branch of the left thyrocervical trunk, ran through the transverse foramen of the fifth cervical vertebra and tapered off to disappear at the first/second cervical vertebrae. 相似文献
23.
本文对300个寰椎的后桥和侧桥的存在情况作了观察。其中129个寰椎(43.0%)有后部分桥,22个寰椎(7.3%)有后完整桥;34个寰椎有侧部分桥(11.3%),16个寰椎(5.3%)有侧完整桥。经统计学检验,在左右侧后完整桥及左右侧侧完整桥间均无显著性差异。对寰椎横突孔、后弧孔及侧弧孔内径的测量显示,绝大部分后弧孔(92.0%)较同侧横突孔小,且右横突孔与右后弧孔间存在高度显著性差异(P<0.01)。此外,还测量了两种完整骨桥的宽度,探讨了狭小后弧孔对正常椎动脉机能的可能影响,分析了文献中关于寰椎桥的起源。 相似文献
24.
Stenosis of the tracheostome is an occasional complication following laryngectomy. Having tried a number of procedures recommended for correction of such stenoses with limited results, we developed a new technique. This technique which is based on multiple Y-V plasties has been applied to 20 patients. Measurements of the stomal area following surgery in 18 patients showed an average increase in stomal size by a factor of 3.8. One patient apparently had no increase of the stoma. In 2, no post-operative measurements were available. Post-operative infection resulted in recurrence of the stenosis in one patient. He was successfully reoperated using the same technique. Follow-up revealed that none of the patients had complaints related to their stoma. 相似文献
25.
Candida albicans vertebral osteomyelitis is rare. Three cases are presented. Without antifungal treatment, they developed spinal collapse and neurological deterioration within 3–6 months from the onset of symptoms. There was a delay of 4.5 and 7.5 months between the onset of symptoms and surgery. All patients were managed with surgical debridement and reconstruction and 12-week fluconazole treatment. The neurological deficits resolved completely. The infection has not recurred clinically or radiologically at 5–6 years follow-up. Although rare, Candida should be suspected as a causative pathogen in cases of spinal osteomyelitis. Without treatment the disease is progressive. As soon as osteomyelitis is suspected, investigations with MRI and percutaneous biopsy should be performed followed by medical therapy. This may prevent the need for surgery. However, if vertebral collapse and spinal cord compression occurs, surgical debridement, fusion and stabilisation combined with antifungal medications can successfully eradicate the infection and resolve the neurological deficits. 相似文献
26.
用33例男性青年新鲜尸体的脊柱,自蛛网膜下腔灌入铸型造影剂.低温冷冻,横断各颈椎照X线片,测出C_3~C_7椎体、椎管、硬膜囊和脊髓的横、矢径平均值。取4例先做脊髓造影CT测量,再做铸型造影对比,证明33例标本测量数值可作为正常男性椎管及脊髓CT测量的标准参考数据。选20例X线片进行图像面积扫描,其中C_4与C_5脊髓与椎管的面积比例较小。 相似文献
27.
28.
目的 探讨椎动脉形态学异常对后循环TIA症状持续时间的影响。
方法 回顾性分析2015年10月-2018年3月在中国科学院大学重庆仁济医院神经内科完成头颈部DSA
或CTA的后循环TIA住院患者临床资料,根据症状持续时间分为<10 min组、10~59 min组和≥60 mi n组,
比较椎动脉形态异常各亚型在3组间的差异。通过多因素Logistic回归分析明确椎动脉形态异常与后
循环TIA症状持续时间之间的关系。
结果 共纳入237例患者,其中症状持续时间<10 min组109例(45.99%)、10~59 min组71例(29.96%)
和≥60 min组57例(24.05%)。一般临床资料的比较显示,性别、椎动脉和基底动脉狭窄率≥50%
在3组间差异具有统计学意义(P<0.05)。椎动脉形态异常中,动脉粥样硬化性椎动脉狭窄(狭窄
率1%~99%)在3组间的差异具有统计学意义(P =0.004),而一侧迂曲、双侧迂曲、一侧优势、一
侧优势合并迂曲和起源异常在3组间差异均无统计学意义;多因素Logi sti c回归分析显示椎动脉
狭窄(OR 2.500,95%CI 1.381~4.525,P =0.002)、基底动脉狭窄率≥50%(OR 12.066,95%CI
1.446~100.668,P =0.021)是TI A症状持续时间延长的独立影响因素。
结论 椎动脉狭窄和基底动脉狭窄率≥50%是影响后循环TIA症状持续时间延长的独立影响因素。 相似文献
29.
改进的内眦赘皮矫治术联合重睑成形术Ⅰ期成形 总被引:7,自引:2,他引:5
目的 探讨改进的内眦赘皮矫治术联合切开法重睑成形术的方法及临床效果。方法 根据内眦赘皮的轻重程度及方向,采用改良的“Z”成形术,切除或切断内眦部形成赘皮的异位眼轮匝肌及皮下筋膜组织,联合切开法重睑成形术行Ⅰ期成形。结果 本组68例患者,术后赘皮消失,泪阜显露适中,内眦间距缩短,重睑外形美观自然。其中,36例随访3个月至3年,术后皮肤切口无可见瘢痕,形态稳定,内眦赘皮无复发,效果满意。结论 该手术方法能够充分矫正内眦赘皮的异常结构,而与重睑成形术同期施术效果稳定,具有一定的临床应用价值。 相似文献
30.
Resource implications of hospitalization for osteoporosis-related vertebral fracture are sparsely documented. This study
utilized data abstracted from a national sample of hospitalized patients to identify characteristics of patients who are hospitalized
with vertebral fracture and their patterns of resource utilization. These were compared with patterns observed for hip fracture
hospitalizations. Data from the Nationwide Inpatient Sample (NIS) for 1997 were used to identify men and women age 45 years
and above who had a primary diagnosis of vertebral fracture. After patients whose fractures might have been due to metastatic
cancer or severe trauma were excluded, 68 901 individuals hospitalized for vertebral fracture were identified. Seventy-seven
percent of these were women, most were white, 75 years and older, and had multiple comorbid diagnoses. Total charges averaged
US$8000–10 000 per hospitalization and were higher in men. Mean length of stay was just under 6 days and more than 50% of
discharged patients required some form of continuing care. Hospitalizations for vertebral fracture occurred at only one-fourth
the rate of those for hip fracture, and created only half the hospital charges per admission. Vertebral fracture accounted
for over 400 000 total hospital days and generated charges in excess of US$500 million. This resource impact is considerably
higher than has been described in prior studies.
Received: 25 June 2002 / Accepted: 13 August 2002
Acknowledgement This research was supported by Procter & Gamble Pharmaceuticals and Aventis. 相似文献