MRI全脊柱移床扫描技术在脊柱转移瘤中的应用

目的 :探讨MRI全脊柱移床扫描技术在脊柱转移瘤中的应用价值。方法 :对 3 7例疑有颈、胸、腰椎转移的患者 ,应用MRI全脊柱移床扫描技术 ,行各段脊柱扫描后 ,采用对接的方法完成全脊柱全程图像。结果 :3 7例均获得直观、准确地显示全部椎管内脊髓及椎体结构的连续图像。椎体单发转移瘤 9例 (颈段 2例 ,胸段 4例 ,腰段 3例 ) ;椎体多发转移瘤 2 5例 (颈、胸、腰段转移 7例 ,胸腰段转移 9例 ,颈、胸段转移 4例 ,颈、腰段转移 5例 ) ;无转移的 3例。结论 :MRI全脊柱移床扫描技术 ,可以很好显示转移瘤的部位、数目及邻近组织、结构侵犯的范围和程度 ,大大提高了定位及定性诊断的准确性。     

Abdominal crush injury in the Sichuan earthquake evaluated by multidetector computed tomography

AIM:To investigate the features of abdominal crush injuries resulting from an earthquake using multidetector computed tomography(MDCT). METHODS:Fifty-one survivors with abdominal crush injuries due to the 2008 Sichuan earthquake underwent emergency non-enhanced scans with 16-row MDCT. Data were reviewed focusing on anatomic regions including lumbar vertebrae,abdominal wall soft tissue, retroperitoneum and intraperitoneal space;and types of traumatic lesions. RESULTS:Fractures of lumbar vertebrae and abdominal wall soft tissue injuries were more common than retro-and intraperitoneal injuries(P<0.05).With regard to the 49 lumbar vertebral fractures in 24 patients,these occurred predominantly in the transverse process(P<0.05),and 66.67%of patients(16/24) had fractures of multiple vertebrae,predominantly two vertebrae in 62.5%of patients(10/16),mainly in L1-3 vertebrae in 81.63%of the vertebrae(40/49). Retroperitoneal injuries occurred more frequently than intraperitoneal injuries(P<0.05),and renal and liver injuries were most often seen in the retroperitoneum and in the intraperitoneal space,respectively(all P< 0.05). CONCLUSION:Transverse process fractures in two vertebrae among L1-3 vertebrae,injury of abdominal wall soft tissue,and renal injury might be features of earthquake-related crush abdominal injury.     

经皮椎体成形术及血管内栓塞化疗治疗椎体恶性肿瘤

目的：观察经皮椎体成形术（PVP）、PVP和血管内栓塞化疗术综合治疗椎体恶性肿瘤的疗效。方法：29例患者（男性16例，女性13例）共40个椎体，转移性肿瘤28例，多发性骨髓瘤1例，均表现为胸腰部疼痛，2例有不同程度的脊髓功能障碍。18例患者共26个椎体单独行PVP治疗，11例16个椎体先后行PVP和（或）血管内栓塞化疗术。结果：29例患者经PVP和血管内栓塞化疗后症状完全缓解者16例（55.1％），部分缓解13例（44.9％），其中PVP不成功1例，再经血管内栓塞化疗疼痛减轻，所有患者无严重并发症发生。结论：椎体恶性肿瘤经PVP和（或）血管内栓塞综合治疗可获得很好的近期疗效，明显提高患者的生存质量。     

MRI全景扫描在脊柱转移瘤中的应用

目的 探讨MRI全景扫描在脊柱转移瘤中的应用价值. 资料与方法 对25例怀疑有脊柱转移的患者,应用MRI全景扫描,行全身及全脊柱分段扫描后,采用对接方法 得到全身及全脊柱全景图像. 结果 25例均获得直观、准确地显示全身冠状位及全脊柱矢状位的连续图像,椎体单发转移瘤11例(颈段1例,胸段4例,腰段6例),椎体多发转移瘤14例(胸腰段6例,全脊柱8例).发现全景扫描前未发现的原发肿瘤8例. 结论 MRI全景扫描可以很好地显示脊柱转移瘤的部位、数目及邻近组织结构受侵的程度和范围,同时有利于原发病灶的发现,大大提高了定位及定性诊断的准确性.     

Dual-phase chemical-shift imaging in the detection of diffuse bone metastasis

Preliminary studies were performed to evaluate the usefulness of lumbar bone marrow MRI using the dual chemical-shift GRE sequence in the detection of diffuse bone metastasis. Two GRE images (TE = 2.3 msec and 4.6 msec) were obtained, and SIR was calculated. SIR was designated as the ratio of in-phase to out-of-phase signal intensity. Among 45 patients with suspicious lumbar bone metastases, diffuse bone metastases were present in 7. Mean SIRs were compared by unpaired t-test. SIRs of diffuse bone metastases had significantly higher signal intensities than those of non-diffuse bone metastases of vertebrae (p < 0.01).     

Factors affecting bone mineral density in elderly men receiving chronic in-center hemodialysis

Twenty-five elderly men receiving chronic hemodialysis had measurements of their bone mineral density (BMD) by dual-photon absorptiometry (DPA). Loss of BMD was much more pronounced in femoral necks than in lumbar vertebrae. Stepwise multiple liner-regression analysis showed that low BMD was associated with 1) hypoalbuminemia, hypermagnesemia, hyperaluminemia, and high serum alkaline phosphatase for femoral necks and 2) hypercalcemia and hypermagnesemia for lumbar vertebrae. These observations suggest that the femoral neck is the preferred site for measurement of BMD in dialysis patients. Along with factors directly affecting bone metabolism, nutritional factors may affect BMD in such patients.     

Vertebral bone mineral measurement using dual photon absorptiometry and computed tomography

The lumbar spine of 14 cadavers was studied both by 153Gd dual photon absorptiometry (DPA) and quantitative computed tomography (QCT) at 96 and 125 kVp. The intact spine and the individual vertebrae were analyzed. After these measurements the ash content of the vertebral body, the posterior elements, and the transverse processes was determined. The fat content of the vertebral body as well as its volume was also measured. With DPA, the bone mineral content (BMC) determined in situ as well as on excised spine specimens correlated highly with the amount of total vertebral ash (r greater than 0.92, SEE less than 3.2 g). The bone mineral density (BMD, area density) of 3 lumbar vertebrae correlated accurately with the mean ash density of the vertebral body (r greater than 0.81, SEE less than 0.015 g/cm3). The so-called corpus density and central density determinations were less accurate. No difference in accuracy was found between measurements when using 3 mm and 4.5 mm step intervals. Variations in the distribution of mineral between the vertebral body and the posterior elements contribute to the error in predicting vertebral body mineral with DPA. QCT gave a smaller error when a cylindric portion of the vertebral body with a 20 mm diameter was measured compared with one with a 9 mm diameter, when the dual energy technique was used (p less than 0.01). With dual energy QCT a correlation was found between a center segment of 3 vertebrae in the lumbar spine and the mean ash density of the vertebral body of r = 0.92 (SEE = 0.010 g/cm3).(ABSTRACT TRUNCATED AT 250 WORDS)     

良恶性多椎体压缩性骨折的MRI诊断

目的:探讨良、恶性多椎体压缩性骨折的MR影像学特征。方法:回顾220例(良性104例,恶性116例)460个压缩椎体,比较病变椎体排列特性及MRI征象。结果:恶性多椎体压缩骨折,椎体跳跃式侵犯多见,66%的病灶集中在椎体后2/3髓质,T1WI呈穿凿样、片状低信号,并椎弓根、椎板表现膨胀性骨质破坏,椎间盘形态正常;良性多椎体压缩性骨折,椎体连续性病变多见,终板表现带状异常信号,常伴椎间盘撕裂、椎间隙狭窄或增宽,椎体碎裂,但无软组织肿块。结论:MR的特征性改变能准确鉴别良、恶性压缩骨折。     

Postmenopausal osteoporosis. Early diagnosis as an indication for preventive hormone therapy

Idiopathic osteoporosis mainly affects postmenopausal women. The normal trabecular volume of the lumbar vertebrae in a sample of healthy perimenopausal women was established by monoenergetic computed tomography. Early diagnosis of diminished bone mass is crucial for the identification of women at risk for involuntary osteoporosis following climacteric estrogen depletion. Body weight, endogenous levels of sex steroids, renal calcium and hydroxyproline excretions are not related to individual bone mass in the lumbar spine.     

Age estimation by assessing the vertebral osteophytes with the aid of 3D CT imaging

The primary objective of this study was to assess the effect of age and sex on the severity and localization of osteophyte formation from three-dimensional (3D) volume rendered (VR) multidetector computed tomography (MDCT) images of thoracolumbar vertebrae. 3D VR MDCT images of thoracolumbar vertebrae of 564 adult living individuals (285 female and 279 male) with ages ranging from 20 to 84 years were studied. The study population was divided into seven groups according to age, and the severity of osteophytosis scored using a scale from 0 to 4 for each vertebra. Osteophyte scores were significantly correlated with age between 40 and 70 years of age in both males and females. Of the four vertebral regions (upper, middle, and lower thoracic, lumbar) the severity was highest in the middle thoracic region between 20 and 70 years of age and in the lower thoracic region between 70 and 90 years. Lower thoracic vertebrae presented a significant sex difference. The localisation and severity of osteophytosis varies with age and shows sexual dimorphism. Our findings will be useful for forensic work in age and sex determination.     

Dynamic quantitative bone scintigraphy in patients with prostatic carcinoma treated by orchiectomy

Dynamic quantitative bone scintigraphy was performed on 31 men with prostatic carcinoma before orchiectomy as well as 2 weeks, 2 and 6 months post-operatively. After injection of technetium methylene diphosphonate Tc 99m (^99mTc-MDP) the count rate was recorded as serial images over the lower thoracic and all the lumbar vertebrae from 1 to 240 min post-injection. Thirteen men had normal bone scintigrams with no changes in^99mTc-MDP content at the four different investigation times. Eighteen men had skeletal metastases. Throughout the study half of the abnormal vertebrae in these patients showed an abnormal count rate after only 6 min post-injection. After 1 h it was possible in almost all abnormal vertebrae to predict abnormal bone uptake. In response to therapy a “flare phenomenon” with an increase in count rate was seen 2 weeks after orchiectomy followed by a decrease 2 months post-operatively in most of the abnormal vertebrae. The count rate decreased even below the pre-operative level after 6 months. Also, the normal vertebrae in the patients with skeletal metastases showed a tendency towards the flare phenomenon, which was not seen in patients with normal bone scintigrams.     

Proliferative myositis in a child

A case of proliferative myositis in the lumbar paraspinal muscles in a 14-year-old boy is presented. Imaging investigations including plain radiograph, ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), bone scan and positron emission tomography (PET) were suggestive of an inflammatory process such as myositis ossificans. The diagnosis was made by incisional biopsy. More pronounced edema, more muscle fiber necrosis and a higher cellularity were found compared to adult cases. The karyotype of the lesion was normal. Clinically, the mass disappeared spontaneously. After 24 months, asymptomatic bridging ossification between the third and fourth lumbar vertebrae was noted. Received: 18 February 1999 Revision requested: 29 March 1999 Revision received: 23 August 1999 Accepted: 24 August 1999     

Bone mineral content and quantitative computerized tomography

Many methods are used to determine bone mineral content (BMC). Quantitative computed tomography (QCT) appears to be the most reliable method also because it allows the trabecular and the cortical bone to be measured separately. QCT is usually performed on the first four lumbar vertebral bodies. BMC is expressed in mg/ml and a mean value is calculated. Three hundred and fifteen subjects were studied (281 women and 34 men). The patients affected with Paget's disease or malignancies, with or without bone metastases, were not included in this study. The measurements were performed by means of a General Electric 9800 tomograph with software and calibration phantom (QCT-Bone program by Image Analysis). Fractured vertebrae were not included when calculating the mean value since an increased density is caused by fracture. The BMC of any studied vertebral body is considered in comparison with the BMC of the other lumbar vertebrae of the same subject. When the BMC of a given vertebral body exceeds the others by 25 mg/ml or more, nodules and/or stripes are observed during multiple-slice scanning of the bone. Lytic areas or angiomas are observed when the BMC of a given vertebral body is -25 mg/ml or higher. In calculating the mean vertebral BMC, vertebrae with both +25 and -25 must be excluded. In this way the method reliability increases.     

Relationship between 99Tcm-MDP uptake and bone mineral density in patients with prostatic carcinoma

Seventeen men with prostatic carcinoma were investigated with quantitative bone scintigraphy and quantitative computed X-ray tomography before orchiectomy and up to 6 months after this operation. The uptake of 99Tcm-labelled methylene disphosphonate (99Tcm-MDP) and bone mineral density (BMD) were determined for each vertebra from Th10 to L4. Ten patients had normal scintigrams. No change in MDP uptake or BMD was seen after 6 months in these patients. Of the seven patients with abnormal scintigrams, one patient had a clinical sign of progression with an increase in both MDP uptake and BMD. The remaining six patients showed stable or improved clinical status. For their abnormal vertebrae a decrease in MDP uptake was seen, while BMD varied in different ways after 6 months. For the normal vertebrae in these patients with metastatic involvement, no change in MDP uptake was seen. However, the BMD values showed a decrease, indicating a generalized increase in bone resorption at sites distant from the metastases.     

Frequency and importance of transverse process fractures in the lumbar vertebrae at helical abdominal CT in patients with trauma

PURPOSE: To evaluate the frequency and importance of transverse process fractures of lumbar vertebrae identified at helical computed tomography (CT) in patients with blunt abdominal trauma. MATERIALS AND METHODS: Helical abdominal CT scans in 536 consecutive patients with a history of blunt abdominal trauma were prospectively evaluated for transverse process fractures of the lumbar spine. The number and level of fractures were categorized and correlated to the retrospective and initial interpretations of the radiographs obtained at original trauma examination. Number and type of associated abdominal injuries were recorded. RESULTS: CT scans showed transverse process fractures in 39 (7.3%) patients. Seventy-nine fractures were identified (single fractures in 12 patients, multiple fractures in 27). Fractures were right-sided in 13 patients, left-sided in 24, and bilateral in two. Transverse process fractures of the L3 vertebra were most common (n = 25). Fractures were not reported in 20 (61%) of 33 initial radiographic assessments. Even at retrospective review, only 30 (57%) of 53 fractures were correctly identified. Transverse process fractures were associated with abdominal injuries in 20 (51%) patients; this association was statistically significant (P <.001). CONCLUSION: Initial conventional radiography is relatively insensitive in the detection of transverse process fractures of the lumbar spine. There is a statistically significant association between transverse process fractures and abdominal injury.     

Metastatic disease of the brain: extra-axial metastases (skull, dura, leptomeningeal) and tumour spread

Extra-axial intracranial metastases may arise through several situations. Hematogenous spread to the meninges is the most frequent cause. Direct extension from contiguous extra-cranial neoplasms, secondary invasion of the meninges by calvarium and skull base metastases, and migration along perineural or perivascular structures are less common. Leptomeningeal invasion gives rise to tumour cell dissemination by the cerebrospinal fluid (CSF), eventually leading to neoplastic coating of brain surfaces. Contrast-enhanced magnetic resonance (MR) imaging is complementary to CSF examinations and can be invaluable, detecting up to 50% of false-negative lumbar punctures. MR findings range from diffuse linear leptomeningeal enhancement to multiple enhancing extra-axial nodules, obstructive communicating and non-communicating hydrocephalus. Both calvarial and epidural metastases infrequently transgress the dura, which acts as a barrier against tumour spread. Radionuclide bone studies are still a valuable screening test to detect bone metastases. With computed tomography (CT) and MR, bone metastases extending intracranially and primary dural metastases show the characteristic biconvex shape, usually associated with brain displacement away from the inner table. Although CT is better in detecting skull base erosion, MR is more sensitive and provides more detailed information about dural involvement. Perineural and perivascular spread from head and neck neoplasms require thin-section contrast-enhanced MR.     

Spinous process fractures associated with Baastrup disease

Patients with Baastrup disease may experience pain owing to irritation of the periosteum or adventitial bursae between abutting spinous processes. We are not aware of any reports in the literature that describe stress fractures of the spinous fractures in patients with Baastrup disease. In this case report, we present two cases of spinous process fractures in lumbar vertebrae associated with Baastrup disease and describe their appearance with conventional radiography, bone scintigraphy, computed tomography (CT) and magnetic resonance (MR) imaging.     

Comparing spondylolysis in cricketers and soccer players

Objective: To determine whether the location of spondylolysis in the lumbar spine of athletes differs with biomechanical factors.

Methods: Single photon emission computerised tomography and reverse gantry computerised tomography were used to investigate 42 cricketers and 28 soccer players with activity related low back pain. Sites of increased scintigraphic uptake in the posterior elements of the lumbar spine and complete or incomplete fracture in the pars interarticularis were compared for these two sports.

Results: Thirty seven (90.4%) cricketers and 23 (82.1%) soccer players studied had sites of increased uptake. In cricketers, these sites were on the left of the neural arch of 49 lumbar vertebrae and on the right of 33 vertebrae. In soccer players there was a significantly different proportion, with 17 sites on the left and 28 on the right (difference of 22.0%; 95% confidence interval (CI) 0.04 to 0.38). Lower lumbar levels showed increased scintigraphic uptake more frequently than did higher levels, although the trend was reversed at L3 and L4 in soccer. Forty spondylolyses were identified in the lumbar vertebrae of the cricketers and 35 spondylolyses in the soccer players. These comprised 26 complete and 14 incomplete fractures in the cricketers, and 25 complete and 10 incomplete fractures in the soccer players. Similar numbers of incomplete fractures were found either side of the neural arch in soccer players, but there were more incomplete fractures in the left pars (14) than in the right (2) in cricketers. The proportion of incomplete fractures either side of the neural arch was significantly different between cricket players and soccer players (difference of 37.5%; 95% CI 0.02 to 0.65). Most complete fractures were at L5 (66.7%) and more were found at L3 (15.7%) than L4 (6.9%). However, incomplete fractures were more evenly spread though the lower three lumbar levels with 41.7% at L5, 37.5% at L4, and 20.8% at L3.

Conclusions: Fast bowling in cricket is associated with pars interarticularis bone stress response and with development of incomplete stress fractures that occur more frequently on the left than the right. Playing soccer is associated with a more symmetrical distribution of bone stress response, including stress fracturing. Within cricketers, unilateral spondylolyses tend to arise on the contralateral side to the bowling arm.

     

The appearances of multiple biliary hamartomas of the liver (von Meyenberg complexes) on computed tomography

Computed tomography is well established in the management of patients with malignant disease, both as a staging procedure before initiation of treatment and in follow up. The presence of unsuspected metastases may affect the decision to perform surgery on the primary tumour and may alter the management of suspected recurrent tumour. Two cases are presented of patients with primary carcinoma whose computed tomography images showed multiple focal hepatic lesions suggestive of metastases. However multiple biliary hamartomas were found on histology, in one case by biopsy and in the other at post mortem. The differential diagnosis and significance of multiple liver defects on computed tomography is considered.     

L_4椎体前滑脱与邻近椎小关节结构变化相关性的CT研究

目的:通过测量L4椎体前滑脱的距离与邻近椎小关节的有关数据,观察两者间的关系。方法:对80例L4滑脱(滑脱组)和80例有腰部疼痛但无L4滑脱(对照组)的患者行64层CT扫描,对比分析邻近椎小关节结构及形态特点。测量邻近椎小关节冠状位、矢状位、横断位的角度、间隙,对获得的数据进行2组间t检验。结果:以L4为中心,分为上下关节;以中轴线为中心,分为右、左关节。2组椎小关节角度、间隙的差异均有统计学意义(P值均<0.05)。结论:随着邻近椎小关节间隙逐渐变窄,冠状位、横断位角度逐渐变大,矢状位角度逐渐变小,L4椎体前滑脱的距离增大,且容易前滑脱。L4前滑脱距离≥4.33mm,对邻近椎小关节影响明显。