An imaging routine for assessing the efficacy of instruments used for scaling and root planning

Deposits of dental plaque or calculus are typically quantified using planimetric techniques. However, error is introduced into a quantitative analysis of plaque deposits using these methods, since they require a significant amount of human intervention. The purpose of this study is to describe and validate a computerized imaging routine which has the potential to objectively identify material on dental roots and measure the area covered by these deposits. Dentiform teeth with simulated plaque were videorecorded. A computer routine was developed based on a flood-fill algorithm which analyzed images of the dentiform teeth and determined the amount of simulated plaque on their root surfaces. Results showed that the dentiform teeth and their simulated plaque patterns are duplicated by the imaging routine in a rapid and reliable fashion. The system shows a high degree of accuracy with an average error factor of only 0.58%. As well, the system enables precise reproducibility with an average error factor of only 0.71%.     

螺旋CT重建技术在颌面外科及正畸中的应用

目的 :探讨螺旋CT重建技术在颌面外科及正畸中的临床应用价值。方法 :颌面部外伤 2 3例 ,口腔畸形 15例。外伤患者行矢状面、冠状面二维重建及骨表面三维重建 ;口腔畸形患者行上、下颌骨三维骨透明重建及口腔曲面重建 ,分析对比轴位图像和重建图像的表现。结果 :① 2 3例颌面骨折经重建后清楚显示骨折线及对位对线情况 ,尤其对于多发的复杂骨折的骨折线全貌、累及范围、颌面部凹陷情况一目了然 ,立体感强。② 15例口腔畸形经重建后清晰显示多生牙、阻生牙的位置、深度 ,及与周围牙齿的关系 ,明确牙弓畸形程度及牙齿拥挤、不齐程度。结论 :颌面部骨折及口腔畸形螺旋CT重建图像对于手术计划制定与实施、牙的矫形前设计均具有重要的临床应用价值。     

软组织血管瘤16层螺旋CT血管成像诊断

目的探讨软组织血管瘤多排CT血管成像的影像表现方法回顾性分析临床、手术及病理证实20例软组织血管瘤CT平扫、增强和CT血管成像的不同表现结果CT平扫病灶呈软组织密度,5例灶内或灶缘见斑点状或斑块状高密度钙化灶;20例增强后病灶血管成像呈不同表现,12例动脉期瘤体内呈网状血管强化并见明显的瘤体供血动脉,其中单支供血动脉4例,2支以上多支供血动脉8例,供血动脉较对侧明显增粗瘤体内明显迂曲静脉血管6例,而静脉期瘤体表现为网状血管阴影强化8例病变动脉期瘤体不强化或仅轻微强化,且无明显供血动脉参与供血,静脉期瘤体逐渐均匀一致强化结论软组织血管瘤的多排螺旋CT血管成像可清晰显示软组织血管瘤的形态、大小、供血血管     

150例颅面部外伤中眼部损伤的CT发现与临床表现的相关性研究

目的　探讨颅面部外伤中眼部损伤的部位和程度与CT扫描发现之间的关系。方法　回顾性分析 15 0例眼部损伤病人的临床表现和CT结果。结果　爆裂骨折多发生于内下壁 ,直接骨折以外壁多见 ,复合骨折常引起多眶壁骨折。合并颅骨骨折 92例。临床表现主要为眶周组织肿胀、眼球运动障碍和视力下降等。结论　CT扫描对眼部损伤病人选择治疗方案和评估预后有重要意义     

食管高密度异物(鱼刺)的CT诊断

目的探讨CT在食管异物诊断中的应用价值方法食管异物10例(均为鱼刺),均行常规CT平扫,必要时加CT薄层扫描,再将CT征象与手术及内镜结果比较结果10例食管异物(鱼刺)均为CT所显示,呈大小、形态不一的稍高或高密度影,其中合并食管出血2例,黏膜下血肿1例,脓肿3例及脓胸1例结论常规CT扫描及薄层扫描在食管异物检查中具有重要意义     

Calcium pyrophosphate dihydrate deposition disease: morphological and microanalytical features

The light microscopic and polarization appearances of calcium pyrophosphate dihydrate crystal deposits in tissues are reviewed. In routine sections haematoxylinophilic crystalline deposits with a feathery or brush-like pattern are typical of calcium pyrophosphate dihydrate. Short rhomboidal crystals showing positive birefringence are seen on polarization; X-ray microanalytical and infrared spectroscopic data support the specificity of these appearances. The appearances of the crystal deposits in decalcified specimens are also described. We include six cases of calcium pyrophosphate dihydrate deposition within periarticular bone; to the best of our knowledge this has not previously been described.     

X线、超声联合导向介入治疗布-加氏综合征

目的:探讨X线、超声联合导向下对布 加氏综合征的介入治疗方法和临床应用价值。方法:本组病人 30例,采用X线和超声联合导向。穿刺下腔静脉闭塞或狭窄部位,经球囊扩张后在X线、超声联合定位置入支架 成形。结果:28例成功,占93%。无严重并发症。术后患者症状明显缓解,下腔静脉压基本恢复正常(治疗前 2.8±0.51kPa,治疗后0.7±0.2kPa)。结论:采用X线、超声联合导向介入治疗布 加氏综合征是一种成功率高、 损伤小、效果可靠的治疗方法。     

双源CT低剂量前瞻性心电触发序列扫描在冠状动脉血管成像的应用

Objective To evaluate low-dose CT coronary angiography with prospective electrocardiogram (ECG)-triggering using dual-source CT scanner.Methods Sixty-eight patients who underwent coronary CT angiography using a dual-source CT scanner were divided into 2 groups: group A (38 cases) and group B (30 cases).Prospective ECG-triggering sequence scan mode was employed for group A.Inclusion criteria included: heart rate <70 bpm, sinus rhythm, and heart rate fluctuation less than 10 bpm.Data acquisition was set at 70% of the RR-interval.Retrospective ECG-gating helical scan was performed for group B.Inclusion criteria included heart rates < 70 bpm and sinus rhythm.The exclusion criteria included heart failure and serious arrhythmias.In both groups, patients with a BMI≥24 kg/m2 were examined with a tube voltage of 120 kV, whereas patients with a BMI <24 kg/m2 were examined with a tube voltage of 100 kV.All images were transferred to a workstation for further processing and analysis.The imaging quality was evaluated.The imaging quality of coronary artery segments were compared with rank sum test between the two groups, and the radiation dose were compared with t test.Results A total of 476 coronary artery segments were evaluated in group A and 372 segments were evaluated in group B.The mean score of imaging quality for coronary artery segments in group A was 3.48±0.59 and that in group B was 3.53±0.58.There was no statistical difference in imaging quality between the two groups (Z=-1.432, P=0.187).The effective dose was on average (2.51±0.54) mSv (range 1.3--3.3 mSv) in group A, whereas on average (14.55±3.54) rosy (range 7.1--20.2 mSv) in group B.There was a statistical difference between the two groups (t=18.484, P=0.000).Conclusions Low-dose prospective ECG-triggering sequence scan in dual-source CT coronary angiography is feasible in patients with low heart rate and regular cardiac rhythm.This scan mode can substantially reduce radiation doses while preserving good diagnostic image quality.     

胆管癌误诊和漏诊的影像学分析

目的：分析胆管癌误诊和漏诊的原因，评价不同检查方法对肝门区胆管癌诊断的价值，提高胆管癌的影像学诊断和鉴别诊断水平。方法：收集31例临床和病理诊断为胆管癌的病例(ERCP检查31例，B超检查31例，25例CT检查，11例行MRCP检查)，回顾性分析不同检查方法的影像学表现。结果：31例中发生在肝门区的胆管癌25例。2例初次ERCP显示胆管内出血，再次行鼻胆管造影后诊断为胆管癌，4例合并有总胆管结石。6例为总胆管中下段癌。初次诊断准确性为90．3％。11例MRCP中9例显示病变，2例显示不满意，7例显示胆管或胆囊结石。25例CT中23例显示肝内胆管扩张，9例显示肝门区肿块，2例见后腹膜转移淋巴结，1例见肝内多发性转移瘤。12例初次诊断正确(48％)。B超检查23例提示肝内胆管扩张，6例提示总胆管结石，18例诊断为胆囊炎、胆囊结石，8例提示胆管占位(25．8％)。结论：良好的直接胆管造影是诊断胆管癌的金标准，MRCP可以在一定程度上准确显示病变的范围，是ERCP的良好补充，很大程度上取代了诊断性ERCP；CT诊断的关键在于显示扩张的胆管和梗阻的定位，肝门区梗阻多为胆管癌所致。多种影像检查方法的结合明显提高了诊断的准确性，对胆管癌治疗方案的选择有重要价值。     

原发性眼眶静脉曲张的CT和MRI表现

目的探讨原发性眼眶静脉曲张(POV)的CT及MRI表现。方法临床诊断的30例原发性眼眶静脉曲张患者,9例行CT横断位和冠状位扫描,21例行MR扫描,4例行CT和MR检查。结果30例中30只患眼,左眼18例,右眼12例,均为单侧发病。病变部位眼睑3例,眼眶前部1例,眼眶后部(球后)17例,眼睑和眼眶前部5例,眼睑、眼眶前部和眼眶后部2例,眼眶前部和眼眶后部2例。形态17例为不规则块状,4例为卵圆形,9例为不规则条状。CT冠状位,病变均显示为软组织密度,有明显强化;静脉石2例;眶骨受压变薄、眶腔扩大3例。MR扫描,颈部加压后25例均显示病变,11例呈等T1长T2信号,7例呈长T1长T2信号,1例呈等T1等T2信号,6例呈长T1长T2为主的混杂信号,增强的22例中,14例呈明显均匀强化,8例呈不均匀强化。结论CT横断位和冠状位及颈部加压或俯卧位MRI在原发性眼眶静脉曲张的诊断和鉴别诊断方面有重要价值。