Tampon Appearance on Bone Scan Imaging: Case Report

The role of a nuclear medicine diagnostic bone scan is well established and the influence of potential artifacts well documented. This case provides an insight into an unusual artifact associated with a tampon in situ and highlights the clinical relevance of single-photon emission computed tomography/computed tomography imaging in differentiating uncommon artifacts from potential pelvic pathology.     

股骨颈疝窝的影像学诊断

目的分析股骨颈疝窝的影像学表现。方法回顾性分析8例股骨颈疝窝的X线平片、HRCT资料,全部病例均行X线、CT检查。结果8例股骨颈疝窝,其中单侧7列,双侧1列,共9个病灶;病灶均位于股骨头基底部或股骨颈前外侧皮质下,X线平片表现为囊性低密度灶,周边环以均匀薄壁硬化圈,CT表现伴清晰均匀薄层硬化圈的低密度灶。结论股骨颈疝窝具有特征性发病部位及影像学表现,X线及CT能明确诊断。     

髋关节撞击综合征的影像学表现

目的：探讨髋关节撞击综合征的影像学表现.材料与方法：回顾性分析21例髋关节撞击综合征的影像学表现.结果：21例患者共发现28个股骨颈疝窝,病灶均位于股骨头基底和股骨颈前外侧皮质下,形态呈圆形、卵圆形或分叶状.X线平片上表现为伴清晰薄层硬化缘的透亮区,CT上表现为伴锐利的薄层硬化缘的骨质缺损区,MRI T1WI序列表现为低信号,T2WI和STIR为高信号.结论：股骨颈疝窝是髋关节撞击综合征的典型征象,CT和MRI可明确股骨颈疝窝的诊断.     

股骨颈疝窝的磁共振弥散加权成像

背景：目前利用磁共振弥散成像反映股骨颈疝窝的水分子弥散特征的研究尚少有报道。目的：利用磁共振表观弥散系数定量测定对股骨颈疝窝和正常股骨颈进行鉴别,探讨股骨颈疝窝的弥散系数值、影像学表现和发病机制。方法：收集18例经病理证实或具有典型影像学征象的股骨颈疝窝影像学患者的资料,全部患者均行X射线平片、CT、常规磁共振成像和弥散加权成像检查。依据CT和常规磁共振成像上异常表现,行股骨颈疝窝弥散系数测量,并与正常股骨颈弥散系数值进行比较。结果与结论：18例患者共20个病灶,均位于股骨头基底和股骨颈前外侧皮质下,形态呈圆形、卵圆形或分叶状。X射线平片上表现为伴清晰薄层硬化缘的透亮区,CT上表现为伴锐利的薄层硬化缘的骨质缺损区,磁共振成像上T1WI为低信号,T2WI为高信号。股骨颈疝窝的表观弥散系数值明显高于正常股骨颈。结果提示,弥散加权成像为股骨颈疝窝的诊断提供有价值的信息,证实股骨颈疝窝的弥散增加和弥散系数值升高。     

A Rare Case of Testicular Embryonal Rhabdomyosarcoma Detected Incidentally on Bone Scan

The role of nuclear medicine diagnostic bone scanning is well established, and the potential for detecting incidental findings is well-known. This case provides an insight into the specific role bone scanning plays in unraveling a complex clinical case. Furthermore, it highlights the importance of single-photon emission computed tomography in differentiating benign from malignant findings, particularly when subtle. The case is an excellent example of a rare disease (adult testicular embryonal rhabdomyosarcoma) requiring correlative imaging and histology for diagnosis.     

Evaluation of Triple-energy Window Method with Two Approximations for Scatter Correction Studies in Single-photon Emission Computed Tomography Imaging Using GATE

Simulations using Monte Carlo packages are increasingly used in nuclear imaging for positron emission tomographic and single-photon emission computed tomographic applications, either for modeling imaging systems or developing algorithms for analysis improvement of image quantifications. This work implemented a GEANT4-based single-photon emission computed tomographic simulation system, GATE, to evaluate the performance of two scatter correction methods: the triple-energy window method using trapezoidal approximation and the triple-energy window method using triangular approximation. A cold-spot hot-background phantom and a resolution phantom were simulated to generate projection images for scatter correction. Both methods were not found to have strictly valid assumptions. A comparative assessment of these two methods was made based on image contrast improvement, image mottle level, and image resolution improvement. Results showed that triangular approximation was better than trapezoidal approximation for contrast improvement with greater image mottle level and some improvement in the resolution of the resolution phantom for both approximations, but trapezoidal approximation with these criteria was better than triangular approximation. A compromise between the contrast improvement and the image mottle level exists. Neither of the two methods performed best for all three criteria.     

Occult fractures of the femoral neck.

Occult fractures of the femoral neck can be subtle or even undetectable on plain radiographs. Yet, untreated, the morbidity of this fracture significantly increases. This report discusses the clinical and radiologic findings seen in occult fractures of the femoral neck. It also discusses the role of tomograms, bone scan, computed tomography, and magnetic resonance imaging in further delineating this entity.     

The Role of Cranial Computed Tomography in the Diagnostic Work-up of Headache

Approximately 18% of all patients referred for a cranial computed tomography complain of headache only.
We reviewed 363 consecutive patients in order to assess the value of this examination in the diagnostic approach.
Despite the vast number of normal examinations (88.4%), we advocate the routine use of a cranial computed tomography in every patient with chronic headache. The cost of the examination can significantly be reduced by performing an unenhanced scan only. An additional contrast-enhanced scan should be obtained if a suspicious lesion is seen. Brain magnetic resonance imaging is not indicated except in the preoperative workup of a lesion visualized on computed tomography.     

The Role of Computed Tomography in the Diagnostic Work‐Up of Headache Patients in Nigeria

Objective.— To determine the yield of computed tomography (CT) scan of the brain in the evaluation of patients presenting with headache at the University of Port Harcourt Teaching Hospital (UPTH). Background.— Headache is a pain in the head or upper neck. It is one of the most common locations of pain in the body that leads patients to see a physician. CT scan is invaluable as an imaging tool in assessment of intracranial lesions that may present with headache. Methods.— The records of all the patients referred from a variety of inpatient and outpatient settings to the radiology department of UPTH with the main complaint of headache for brain (CT) scan were identified. Data extracted include referral source, indication for CT, age, sex, presenting complaint, duration of headache, and CT findings. The data were analyzed using SPSS 14.0 statistical package. Results.— A total of 80 patients with chronic or recurrent headache met the selection criteria. The age range was 16 to 85 years with a mean of 39.8 ± 14.62 years. There were 36 males and 44 females with male to female ratio of 1 : 1.2. About half of the patients were ≤45 years. Of the total number, 72 (90%) patients had normal CT findings, 2 (2.5%) had cerebral atrophy, 2 (2.5%) had cerebral edema, 2 (2.5%) had intracerebral hematoma while 1 (1.25%) patient each had cerebral infarction and subdural hematoma, respectively. There was no case of brain tumor. Conclusions.— The yield of correctable abnormalities from routine CT scan of the brain in headache patients with normal neurologic findings is low and does not justify its use in a resource poor country. (Headache 2010;50:1346‐1352)     

Observer Performance in Computed Tomography Head Reporting

AimTo audit the reporting results of a cohort of radiographers (n = 6) completing an accredited academic program in clinical reporting of computed tomography (CT) head examinations.MethodsAn audit of retrospective academic image case banks and prospective random clinical workload case banks. Both the academic test banks and clinical workload banks included a wide range of normal and abnormal cases of different levels of difficulty and pathology. Abnormalities included hemorrhage, fractures, lesions, infarctions, degeneration, and normal variants from a variety of referral sources. True positive and negative, as well as false positive and negative fractions were used to mark the reports, which were analyzed for accuracy against a reference standard. Furthermore, interobserver variability was assessed using Cohen’s kappa, one-way analysis of variance, and Tukey for multiple comparisons and significance testing at 95% confidence intervals (CI).ResultsThe mean accuracy score for all radiographers (n = 6) and reports (n = 3,008) was 90.7% (95% CI, 88.3%–93.0%). Mean sensitivity and specificity rates were 86.9% (95% CI, 85.8%–88.2%) and 94% (95% CI, 89.6%–98.3%), respectively. The most common errors were associated with herniation, lacunar infarctions, and subtle fractures (false negatives) and involutional changes, subtle infarctions, and ventricular dilation (false positives).ConclusionsThe results suggest appropriately trained radiographers can successfully undertake to report computed tomography head examinations to a high standard. The adoption of both academic and clinical workload image banks that reflect disease examples and the prevalence that may logically be encountered in practice offers the potential for an accurate measure of performance of radiographer's abilities.     

多层螺旋CT对下颌骨骨折的诊断价值

目的探讨多层螺旋CT对下颌骨骨折的诊断价值。方法对2007年4月2009年10月下颌骨不同部位骨折的45例患者进行多层螺旋CT轴位扫描,并行多平面、表面遮盖法等三维重建,对下颌骨骨折CT表现特征作回顾性分析。结果 45例下颌骨骨折中,位于下颌体骨折24例,下颌角骨折5例,下颌升支骨折6例,髁部骨折13例,冠突骨折2例;颞下颌关节脱位中,单侧脱位3例,双侧脱位5例。结论多层螺旋CT能准确诊断下颌骨各部位骨折,对诊治方案具有重要价值。     

Computed Tomography in the Headache Patient: Is Routine Evaluation Really Necessary?

SYNOPSIS
Objective . To determine the likelihood ratio of a positive computed tomogram of the brain in the routine evaluation of headache patients.
Design . Consecutive patients with a chief complaint of headache were prospectively evaluated with computed tomography of the brain. Patients with headaches complicating other clinical disorders such as trauma, postictal state or known intracranial neoplasm were excluded.
Setting . Military tertiary care center.
Patients . Consecutive sample of 350 patients with a chief complaint of headache, regardless of the presence or absence of physical or neurologic signs, were referred for computed tomography of the brain. The patients were referred from a variety of inpatient and outpatient settings.
Results . Seven (2%) of the 350 patients had computed tomographic findings that were clinically significant. An additional 25 (7%) had positive computed tomographic findings, which were clinically insignificant for findings. All of the patients with significant computed tomographic findings had an abnormal physical or neurologic exam or unusual clinical symptoms.
Conclusion . Routine computed tomography of the brain in headache patients with normal physical and neurologic exams and no unusual clinical symptoms has a low likelihood ratio for discovering significant intracranial disease.     

Single-photon Emission Tomography/Computed Tomography Delineation of Freiberg Infraction

The role of nuclear medicine diagnostic bone scanning is well established and the influence of coregistration between single-photon emission computed tomography and computed tomography well documented. This case provides an insight into a less frequently encountered pathology in which the combination of single-photon emission computed tomography and computed tomography permitted the differentiation of potential pathology.     

炎性肌纤维母细胞瘤计算机断层摄影表现

  目的  探讨炎性肌纤维母细胞瘤的计算机断层摄影(computed tomography, CT)表现, 以提高对该病CT表现的认识。  方法  选择本院9例经病理证实的炎性肌纤维母细胞瘤患者, 回顾性分析其CT平扫及增强表现。  结果  CT示肺内肌纤维母细胞瘤3例, 2例表现为界限清楚的肿块, 1例仅表现为支气管阻塞, 未见肿块; 纵隔肌纤维母细胞瘤3例, CT均表现为软组织密度肿块, 1例界限清楚, 2例与周围结构分界不清; 鼻根部、颈部及盆腔肌纤维母细胞瘤各1例, 表现为囊实性或实性肿块, 部分病变界限不清, 侵犯周围组织; 3例病变增强扫描后呈明显不均匀强化。  结论  炎性肌纤维母细胞瘤CT表现具有一定的特点, 但最终确诊仍需依靠病理学。     

基于CT值及三维重建的股骨骨段骨密度值快速求解研究

目的 探讨基于CT值及三维重建的股骨、股骨头、股骨颈、股骨髁骨密度值快速求解方法.方法 采用12侧成人尸体下肢标本为实验材料,实验分成实验组及真实测量组.实验组按0.5 mm层距进行股骨CT扫描、三维重建、读取像素CT值数据;将股骨三维模型骨段分为股骨头、股骨颈、股骨干及股骨髁,分别读取股骨及各段三维模型的像素CT值数据.真实测量组经标本制作、分别测量整体股骨及各段的质量及体积,计算骨密度值.实验组三维模型像素CT值均值与真实测量组骨密度值进行相关分析,获得像素CT值均值与骨密度值的数学函数关系,通过函数计算出来的骨密度值与真实测量组进行单因素方差分析.结果 (1)骨密度真实测量值与CT值均值的相关分析:整体股骨y=0.2535x0.2901,R2 =0.9464;股骨头y=0.027x0.6085,R2=0.915;股骨颈y=0.0324x0.5849,R2=0.862;股骨髁y=0.0245x0.814,R2=0.8492.(2)骨密度计算值与真实测量值的单因素方差分析:整体股骨P=0.987;股骨头P=0.984;股骨颈P=0.962;股骨髁P =0.971.结论 (1)股骨三维重建后通过像素CT值均值可以快速求解骨密度值;(2)骨段进行股骨骨密度值测量结果精确,质量控制良好;(3)为临床快速骨密度值求解提供实践手段及理论依据.     

正电子发射计算机断层显像在脑梗死治疗中的应用进展

脑梗死系由各种原因所致的局部脑组织血液供应障碍,导致脑组织缺血缺氧性病变坏死,进而产生临床上对应的神经功能缺失表现。本文对正电子发射计算机断层显像在脑梗死治疗中的应用进行总结。     

64排螺旋CT冠脉成像质量与护理

目的：探讨64排螺旋CT冠状动脉成像中的重要性，减少影响影像质量因素，提高诊断成功率。材料与方法：对我院2007年4月-2008年1月62例实施检查前护理措施，取得病人，配合和信任。所有患者碘试阴性，保证对比剂顺利注入。结果：62例病人心率控制在70次／min以下，图像质量能够满足影像学评价，所有病人留置套管针，无1例渗漏，有选择性筛选病人，无1例过敏反应。结论：细致、有效针对性护理对提高影像质量至关重要。     

Computed Tomographic Localization of Malposition of Pacing Electrodes: The Value of Cardiovascular Computed Tomography

Three patients with uncertain pacemaker electrode position on plain film radiography were studied with fast cine cardiovascular computed tomography (CT) imaging. The value of this new technique in determining the position of pacing electrodes is discussed.     

单光子发射计算机断层成像术平面和断层骨显像在青少年腰椎峡部裂诊断中的价值

目的 研究单光子发射计算机断层成像术(SPECT)平面和断层骨显像对青少年腰椎峡部裂(spondylolysis)的诊断价值.方法 115腰痛青少年患者行骨扫描,男66例,女49例,年龄11～22岁,平均(15.9±4.2)岁.最终47例诊断为腰椎峡部裂,68例排除了腰椎峡部裂.回顾性分析SPECT平面骨显像和断层骨显像诊断腰椎峡部裂的显像特点和价值.结果 SPECT平面骨显像诊断腰椎峡部裂的准确度、敏感度、特异度、阳性预测值、阴性预测值分别为85.2％、53.3％、98.5％、96.9％、80.7％;SPECT断层显像诊断诊断腰椎峡部裂的准确度、敏感度、特异度、阳性预测值、阴性预测值分别为:93.0％、87.2％、97.1％、95.3％、91.7％.结论 SPECT平面骨显像可发现大多数腰椎峡部裂患者,而SPECT断层骨显像在不增加射线剂量的前提下可灵敏的诊断腰椎峡部裂.     

双螺旋CT诊断肺动脉栓塞的临床研究

目的：评价双螺旋CT在诊断肺动脉栓塞（pulmonary embolism;PE)中的价值,着重研究小肺动脉栓塞及大肺动脉内的细小栓子的显示方法和诊断依据。方法：对39例临床拟诊为PE的患者,进行双螺旋CT肺动脉造影（DSCTPA）检查,且全部病例均经随诊证实。结果：中央型PE15例,周围型PE19例。检出PE的直接征象392处,间接征象51例。DSCTPA诊断周围型PE的敏感性为95％,特异性为75％。结论;双螺旋CT作为一种无创的检查方法,对诊断肺动脉栓塞可靠,能够明显提高小肺动脉栓塞的检出率。