Influence of "optical illusion" on the detectability of pneumothorax in diagnosis for chest CT images: substantiation by visual psychological simulation images

Some cases have been reported in which an optical illusion of lightness perception influences the detectability in diagnosis of low-density hematoma in head CT images in addition to the visual impression of the photographic density of the brain. Therefore, in this study, the author attempted to compare the detectability in diagnosis for chest images with pneumothorax using visual subjective evaluation, and investigated the influence of optical illusion on that detectability in diagnosis. Results indicated that in the window setting of lung, on such an occasion when the low-absorption free space with pneumothorax forms a crescent or the reduced lung borders on the chest-wall, an optical illusion in which the visual impression on the difference of the film contrast between the lung and the low-absorption free space with pneumothorax was psychologically emphasized when contrast was observed. In all cases the detectability in diagnosis for original images with the white thorax and mediastinum was superior to virtual images. Further, in case of the virtual double window setting of lung, thorax, and mediastinum, under the influence of the difference in the radiological anatomy of thorax and mediastinum as a result of the grouping theories of lightness computation, an optical illusion different from the original images was observed.     

Visual impression of photographic density of the brain in head CT images: verification of optical illusion by visual subjective evaluation of medical images

The purpose of this study was to clarify the psychological influence of optical illusion on the photographic density of the brain in head CT images. In this study, I attempted to compare the visual impression of photographic density of the brain using visual subjective evaluation according to observers and cases. The results showed that the visual impression of photographic density of the brain at cerebellar CT depended upon the mode of appearance of the optical illusion (assimilation, contrast, picture frame effect, etc.). In addition, that impression varied according to differences in cases (difference of picture pattern) and observers. Further, it was clarified that the optical illusion had been observed according to individual differences among observers. Moreover, cases could be divided into two main classes. Some cases were recognized as a kind of outline figure (the white skull was recognized as an induction color, and the brain as a non-induction color) with assimilation, and consequently the brain seemed whitish. In other cases (the white skull was not recognized as an induction color) in which there was no assimilation, the brain did not seem whitish. This was considered to have occurred because the degree of influence of the skull on the visual impression of the photographic density of the brain had changed according to differences in cases.     

颅脑减速伤的损伤特点研究

目的研究颅脑减速伤的损伤特点,探讨其在颅脑创伤的伤情判断和影像诊断中的应用价值。方法分析361例临床典型颅脑减速伤患者的颅脑CT影像资料,结合致伤病史及临床资料,总结归纳颅脑减速伤的损伤特点。结果颅脑减速伤损伤的主要特点为:撞击部位头皮损伤、颅盖骨折、硬膜外血肿、硬膜下血肿和脑挫裂伤,对冲部位硬膜下血肿、颅底骨折和脑挫裂伤;颅骨骨折以撞击部位多见,硬膜下血肿以对冲部位多见,蛛网膜下腔出血主要位于脑底部及脑挫裂伤区;额、颞叶严重对冲伤是常见颅脑减速伤的重要特征。结论根据颅脑减速伤的损伤特点,结合致伤病史或颅脑CT表现,可为临床颅脑减速伤伤情的快速判断与救治、CT扫描及诊断、创伤事故原因的评判提供理论依据。     

成人外伤性脑梗死的CT诊断

目的 探讨成人外伤性脑梗死的影像特点.方法 分析30例成人外伤性脑梗死的临床与CT资料.结果 脑叶梗死17例,基底节-内囊区梗死13例,伴蛛网膜下腔出血15例,硬膜下血肿9例,硬膜外血肿3例,脑内血肿3例,脑疝5例,出血性脑梗死2例.结论 CT发现成人外伤性脑梗死的最佳时间是外伤后24 h～6 d,梗死多伴有颅脑损伤的其他CT表现,临床结合动态CT观察是诊断成人外伤性脑梗死的有效方法.     

Strangulation in child abuse: CT diagnosis

The central nervous system is commonly affected in child abuse. Between April 1985 and July 1986 three infants were identified in whom the primary mode of injury had been strangulation. In each case computed tomography (CT) demonstrated a large cerebral infarction confined to vascular territories associated with small subdural hematomas. There was no history or visible evidence of significant head trauma. Autopsy of one infant confirmed the presence of a hemispheric infarct, thin subdural hematoma, and an area of subintimal hemorrhage in the carotid artery ipsilateral to the infarct. The remaining two patients survived with residual hemiparesis. CT findings of a large cerebral infarction with an associated subdural hematoma in an infant without a history of a significant trauma should suggest the possibility of child abuse and may be the primary manifestation of abuse in some patients.     

彩色超声对重型颅脑损伤术中急性脑膨出的诊断及治疗价值

目的 探讨彩色超声对重型颅脑损伤术中急性脑膨出的诊断及治疗价值.方法 回顾性分析2013-12至2018-12武警北京总队医院和武警四川总队医院收治的32例重型颅脑损伤术中发生急性脑膨出患者的临床资料,术中采取超声检查的方法,诊断脑膨出的病因及进一步指导手术治疗方案.观察记录术中超声诊断脑膨出的病因类别、部位特点(包括...     

CT for acute stage of closed head injury

Brain damage after head injury can be classified by its time course. Primary damage that includes acute subdural hematoma (SDH), acute epidural hematoma (EDH), and intraaxial lesions that include contusions, diffuse axonal injury (DAI), and intracranial hemorrhage (ICH), occurs at the moment of impact and is thought to be irreversible. Secondary damage that includes herniations, diffuse cerebral swelling, and secondary infarction and hemorrhage, evolves hours or days after injury as a consequence of systemic or intracranial complications. The duration and severity of secondary damage influence outcome. Head injury management is focused on preventing, detecting, and correcting such secondary damage. CT has been widely used for the neuromonitoring of head trauma. CT is the gold standard for the detection of intracranial abnormalities and is a safe method for survey. While MRI is more sensitive and accurate in diagnosing cerebral pathology, CT is considered the most critical imaging technique for the management of closed head-injured patients in the acute stage. In this article, we review the imaging findings and literature of various lesions of closed head injury in the acute stage.     

Delayed epidural hematoma after evacuation of a subdural hematoma

CT easily diagnoses epidural hematomas. The appearance of an epidural hematoma may be delayed by compression from a contralateral lesion. The possibility of a delayed epidural hematoma should be kept in mind in the presence of additional findings such as a skull fracture contralateral to the original lesion or decompression of the epidural hematoma into either the subgaleal or the subarachnoid space. We present a case in which an epidural hematoma declared itself after the evacuation of a contralateral subdural hematoma.     

汶川大地震颅脑损伤概况及多层螺旋CT的诊断价值

目的 总结汶川大地震颅脑损伤情况及多层螺旋CT的诊断价值.方法 对收治的汶川地震伤员1557例中因颅脑外伤的292例进行CT检查,其中CT检查阳性者225例.回顾性总结225例颅脑损伤患者的损伤类型及多层螺旋CT表现,分析多平面重组(MPR)及三维(3D)重组成像的应用价值.结果 颅脑损伤225例,主要包括颅骨骨折66例,脑挫裂伤50例,颅内血肿55例,蛛网膜下腔出血16例,硬膜下积液16例,头皮异物20例,外伤性脑梗死2例.其中22例进行了手术治疗.结论 地震住院救治伤员中颅脑损伤占的比例较大,MPR及3D图像可以为神经外科医师术前提供直观可靠的依据.     

脑弥漫性轴索损伤的CT诊断价值（附45例分析）

目的　探讨CT对脑弥漫性轴索损伤的诊断价值。方法　对 45例脑弥漫性轴索损伤患者的早期CT表现进行回顾性分析。结果　 45例脑弥漫性轴索损伤早期CT表现为弥漫性脑肿胀 45例 ,脑白质内单发或多发小出血灶 (大脑半球 1 8例 ,基底节区1 0例 ,脑干 3例 ) ,蛛网膜下腔出血 2 1例 ,脑室内出血 8例 ,硬膜下血肿 7例 ,硬膜外血肿 5例 ,颅骨骨折 9例。结论　CT检查对脑弥漫性轴索损伤具有较高的诊断价值     

Visual impression of photographic density of lung, thorax, and mediastinum in chest CT images: verification of optical illusion by visual subjective evaluation of medical images

Even if the brain in head CT images is shown physically at the same photographic density, optical illusion (assimilation, contrast, etc.) occurs and practical density can be observed psychologically differently. Therefore, in this study, in order to clarify the visual characteristics of lightness perception in chest CT images, I attempted to compare it with the visual impression of the photographic density of lung, thorax, and mediastinum, using visual subjective evaluation. The results were as follows. (1) In the case of the preferential window setting of lung, both thorax and mediastinum, which surround the lung, are recognized as a wide white frame with contrast, and the photographic density of the lung psychologically seems blackish as a result of the "picture frame effect". (2) In the case of the preferential window setting of thorax and mediastinum, the visual impression of the photographic density varies among observers. (3) In the case of the virtual double window setting of lung, thorax, and mediastinum, under the influence of both high-density and low-density areas in the radiological anatomy of thorax and mediastinum, the photographic density of lung psychologically appears whitish as a result of the "grouping theories" of lightness computation. Further, under the influence of original gray lung, the photographic densities of thorax and mediastinum psychologically appear to be whitish.     

急性大脑镰和小脑幕硬膜下血肿的CT及磁共振成像诊断

目的探讨急性大脑镰和小脑幕硬膜下血肿的CT及磁共振成像特征。方法回顾性分析17例急性大脑镰和小脑幕硬膜下血肿的CT及磁共振成像表现。结果 17例急性大脑镰和小脑幕硬膜下血肿中,大脑镰硬膜下血肿5例,小脑幕硬膜下血肿7例,大脑镰并小脑幕硬膜下血肿5例,6例伴有颅盖骨(大脑凸面)部位的硬膜下血肿或脑实质挫裂伤。结论急性大脑镰和小脑幕硬膜下血肿较少见,易误诊为蛛网膜下腔出血、大脑镰钙化,CT和磁共振成像征象具特征性,有助于鉴别。     

Subdural hematomas due to ruptured cerebral aneurysms: angiographic diagnosis and potential pitfall for CT.

Two patients with subdural hematoma secondary to rupture of intracranial aneurysms are described. Computed tomography and plain skull films are generally the examination of choice for the patient with significant head trauma. In selected patients, however, cerebral angiography in place of, or along with, computed tomography may be necessary to demonstrate an underlying cause for the subdural hematoma.     

双侧瞳孔散大的外伤性脑疝手术疗效分析

目的探讨双侧瞳孔散大的外伤性脑疝的手术效果和影响因素。方法67例双侧瞳孔散大的外伤性脑疝患者按原发损伤类型分组并接受手术治疗，于术后半年进行格拉斯哥预后评分（GOS）。结果全组恢复良好3例，中残10例，重残9例，植物生存10例，死亡35例。其中，硬膜外血肿组预后最好，弥漫性脑肿胀组最差，其差异有统计学意义（P〈0．05）。结论双侧瞳孔散大的外伤性脑疝手术疗效与脑原发损伤类型密切相关，硬膜外血肿所致的晚期脑疝应积极手术治疗，患者预后较佳；急性弥漫性脑肿胀所致晚期脑疝手术意义不大；部分脑挫伤和（或）硬膜下血肿导致的晚期脑疝患者经手术治疗仍能够挽救生命。另外，快速准确的术前诊断、恰当的术式选择和围手术期处理是救治成功的必要保证。     

急性期脑内血肿3.0T MR扩散加权成像表现

目的:探讨3.0T MR设备中平面回波扩散加权成像(EPI-DWI)和表观扩散系数(ADC)图对急性脑内血肿的诊断价值及与脑梗死的鉴别诊断能力。方法:对18例急性期脑内血肿患者行EPI-DWI检查,获得ADC图并与CT及常规MRI进行对比。同期选择发病时间、病变体积相近的急性脑梗死患者18例,比较急性期脑内血肿与脑梗死的MRI表现。结果:所有急性期脑内血肿在EPI-DWI及ADC图上均为混杂信号,尤其是较大血肿;不同大小血肿周边均可见低信号环。所有急性脑梗死病变均未见周边环状低信号。结论:血肿周边低信号环为急性期脑内血肿的特异性DWI表现,可资与急性脑梗死相鉴别。     

儿童硬膜外血肿的治疗

目的 探讨儿童硬膜外血肿的临床特点及其治疗方法。方法 回顾性分析我院2001年1月～2003年12月收治的儿童硬膜外血肿120例。结果 婴幼儿和学龄前儿童受伤原因以坠落伤及摔伤为主，7岁以上儿童以交通伤为主。65.8％(79/120)的患儿合并有颅骨骨折，格拉斯哥昏迷评分(GCS)平均13．6分。急性血肿除立即手术者外，其他于首次发现血肿1d后及3d左右再复查CT。手术者占57.5％(69/120)，术中发现血肿来源于板障出血的占44％(29/66)。结论 儿童硬膜外血肿的原发颅脑损伤相对较轻，颅骨骨折的发生率低于成人，板障出血为血肿形成的首要原因。有必要做多次CT检查，经恰当治疗预后良好。     

Rapid wireless transmission of head CT images to a personal digital assistant for remote consultation

RATIONALE AND OBJECTIVES: We describe a simple technique for transmission of a complete set of cranial computed tomography (CT) images to a commercially available wireless personal digital assistant (PDA) for remote teleradiology consultation. MATERIALS AND METHODS: A complete set of images from the head CT of a trauma patient with subdural hematoma (19 images) was captured from a picture archiving and communication system and transmitted wirelessly as an e-mail attachment after being compressed. The images were retrieved, decompressed, and reviewed using commercially available software and a PDA with cellular phone capability. RESULTS: A complete head CT was transmitted to a remote radiologist's wireless PDA for consultation. The entire procedure (including image capture, transmission, and review) took approximately 11.5 minutes. CONCLUSION: Using the technique described in this article the wireless PDA may function as a robust medium for facilitating care of brain trauma patients by allowing rapid access to trauma radiologists or neurosurgeons.     

弥漫性轴索损伤的CT表现

目的　加深对弥漫性轴索损伤 (DAI)CT表现的认识 ,以助于临床早期正确诊断。方法　回顾性分析 56例DAI的临床及CT资料 ,其中男 44例 ,女 1 2例 ,车祸伤 43例 ,高处坠落伤 1 3例 ,全部病例均具有伤后立即原发性昏迷。结果　①脑实质出血灶 44例 ,呈斑点状 ,直径多小于 2cm ,主要位于胼胝体、脑干、基底节 -内囊区及皮髓质交界部。②蛛网膜下腔或 /和脑室出血 41例。③弥漫性水肿 9例。④合并硬膜外血肿 5例 ,硬膜下血肿 1 6例。结论　DAI的CT征象有其特点 ,对于临床早期正确诊断具有重要参考价值     

Magnetic resonance of the brain: the optimal screening technique

Magnetic resonance (MR) images and computed tomograms of 25 patients with head trauma were compared. MR proved to be superior in many ways for demonstrating extracerebral as well as intracerebral traumatic lesions. Isodense subdural hematomas, which present a diagnostic dilemma on CT images were clearly seen on MR, regardless of their varying CT densities. In a case of epidural hematoma, the dura mater was shown directly as nearly devoid of signal on MR. Direct coronal images provided excellent visualization of extracerebral collections along the peritentorial space and subtemporal area. In a patient with intracerebral hematoma, CT failed to demonstrate residual parenchymal changes in a 3-month follow-up study, but MR clearly depicted the abnormalities. The superiority of MR over CT was also well illustrated in a patient with post-traumatic osteomyelitis of the calvarium.     

Computed tomography of craniocerebral injury in the abused child.

Computed tomography (CT) was performed in 26 infants and children with craniocerebral trauma related to abuse during a 41-month period. The pattern of brain injury differed from that seen in the nonabused traumatized infant or child. Parieto-occipital acute interhemispheric subdural hematoma (AIHSH) with associated parenchymal injury was the most frequent finding (58%). Follow-up by CT in patients with AIHSH demonstrated infarction in half and cerebral atrophy in all.