Computer-Assisted Detection of Pulmonary Nodules: Preliminary Observations Using a Prototype System with Multidetector-Row CT Data Sets

The continued revolution in multidetector-row CT (MDCT) scanning increases the quality of lung imaging but at the cost of a greater burden of data for review and interpretation. This article discusses our preliminary experience with prototype software for lung nodule detection and characterization using MDCT data sets. We discuss the potential role of computer-assisted detection (CAD) as applied to the automatic detection of lung nodules. We also review the process of CAD, outline its potential results, and explore how it may fit into existing radiology practice. Finally, we discuss MDCT data-acquisition parameters and how they may affect the performance of CAD.     

全脑全脊髓照射仰卧位CT模拟定位技术

目的：探讨全脑全脊髓照射仰卧位CT模拟定位技术。方法：7名患者分别躺在真空负压袋固定器上，进行CT模拟定位，打印正侧位数字重建射线彩像（DRR）图，放射治疗前拍摄正侧位定位验证片，测量解剖参考点和射野边界之间的距离。结果：患者左右方向及背腹方向误差在2mm以内。人体上下方向误差在4mm以内；放疗后，患者受照射的皮肤部位均出现色素沉着。结论：仰卧位全脑全脊髓照射CT模拟定位技术可用于俯卧位不合作的患者。     

Computed tomographic study of the posterior condylar angle in arthritic knees: its use in the rotational positioning of the femoral implant of total knee prostheses

The epicondylar axis is a reliable reference to check the rotation of the femoral implant in total knee prostheses (TKPs). However, during the operation it seems easier to use the posterior condylar axis as a landmark. The angle between these two axes is called the posterior condylar angle (PCA). The aim of this study was to measure the PCA in arthritic knees to assess the reliability of the posterior condylar axis as a reference for the control of the rotation of the femoral implant and to look for correlation with other radiological measurements. This prospective study consisted of 103 arthritic knees (81 varus, 22 valgus) before a TKP had been done in 103 patients (75 women, 28 men). The assessment of the PCA was made by computed tomographic scanning (CT). The HKA, HKS and HKT angles were measured on the pangonogram. The posterior condylar axis was internally rotated with respect to the epicondylar axis. The average value for all the patients was 2.65° degrees with a range from 0° to 7°. The PCA was significantly increased in the valgus knees. There was no correlation between the angles on the pangonogram and the posterior condylar axis. While the preoperative assessment of the PCA by CT scanning is reliable, the results obtained indicate the marked variability in its value. If one wishes to use the posterior condylar axis as a guide for rotation, it is therefore necessary to assess the PCA for each patient using adjustable jigs according to the value obtained. No measurement on standard radiographs allowed an extrapolation of the value of the PCA, and CT scanning seems to be the preferable radiological examination.

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Electronic Supplementary Material The french version of this article is available in the form of electronic supplementary material and can be obtained by using the Springer Link server located at

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Etude tomodensitométrique de l'angle condylien postérieur dans les genoux arthrosiques. Intérêt dans le positionnement en rotation de l'implant fémoral dans les prothèses totales de genou

Résumé L'axe épicondylien est une référence fiable pour le contrôle de la rotation de l'implant fémoral dans les prothèses totales de genou (PTG). Mais, lors de l'intervention, il semble plus facile d'utiliser l'axe condylien postérieur comme repère. L'angle entre ses deux axes est appelé angle condylien postérieur (ACP). Le but de cette étude était de mesurer l'ACP dans les genoux arthrosiques, d'évaluer la fiabilité de l'axe condylien postérieur comme référence pour le réglage de la rotation de l'implant fémoral, de rechercher une corrélation avec d'autres mesures radiologiques. Une étude prospective comportant 103 genoux arthrosiques (81 varus et 22 valgus), avant PTG a été effectuée, chez 103 patients (75 femmes et 28 hommes). L'évaluation de l'ACP a été faite par examen tomodensitométrique (TDM). Les angles HKA, HKS et HKT ont été mesurés sur le pangonogramme. L'axe condylien postérieur était en rotation interne par rapport à l'axe épicondylien. La valeur moyenne pour tous les patients était de 2.65°, avec des valeurs de 0 à 7°. La valeur de l'angle CP augmentait avec une différence significative dans le groupe des genu valgum. Il n'y avait pas de corrélation entre les angles du pangonogramme et l'ACP. Si l'évaluation pré-opératoire de l'ACP par TDM est fiable, les résultats obtenus mettent en évidence une variabilité importante de sa valeur. Il faut donc, si l'on veut utiliser l'axe condylien postérieur comme repère de rotation, évaluer pour chaque patient l'ACP, et utiliser un ancillaire réglable reportant la valeur obtenue. Aucune mesure sur des radiographies standard ne permettant d'extrapoler la valeur de l'ACP, la TDM semble l'examen radiologique de choix.

     

The familial prevalence in second-degree relatives of patients with anxiety neurosis (panic disorder)

A family history study of second-degree relatives of 19 patients with anxiety neurosis (panic disorder) and 19 controls showed a morbidity risk of 9.5% among the former compared with 1.4% among the latter. These risks were approximately half those found among first-degree relatives. Female relatives were at higher risk for anxiety neurosis. The risk for other psychiatric illnesses did not differ between the relatives of anxiety neurosis and controls.     

Morphometric analysis of the thoracic and lumbar spine in Japanese on the use of pedicle screws

The pedicle screw and hook have become popular instruments in treating spinal deformity and disease. This study gathered morphological data on thoracic and lumbar spines in a Japanese population that should serve as useful reference for posterior instrumentation surgery. One hundred and three dry bones were used to investigate the morphology of pedicle and facet in thoracic and lumbar spines. Measurements included the diameter and axial length of pedicle from T8 to L5, height and width of facets and thickness of articular processes from T1 to T12, and axial angle of pedicle from T1 to L5. The diameter and axial length of pedicle were smallest at T8, diameter was largest at L5 and axial length was largest at L3. Height of facets and thickness of articular processes were largest at T12. Men tended to have larger pedicles and facets than women. Transverse angle of pedicle was smallest at T12. These precise data may provide useful information when performing posterior instrumentation surgery and when developing new spinal implant systems for Asians.     

Post-traumatic epidural hematoma in two patients with long-standing “arrested” hydrocephalus

The occurrence of a post-traumatic epidural hematoma in two patients with long-standing arrested hydrocephalus is reported. There was a relatively long interval between the head injury and the onset of symptoms. The large hematoma was accommodated by the decrease in size of the markedly dilated ventricles. This report stresses the possibility of the presence of an epidural hematoma in the management of head injury in patients with long-standing arrested hydrocephalus.     

Computed tomographic scans in ECT-patients

Although the safety and efficacy of electroconvulsive therapy (ECT) is acknowledged by most, concern has repeatedly been expressed that the treatment may have some lasting effects on the brain. To study potential morphological changes, 22 patients with a history of ECT were submitted to a detailed clinical evaluation and a brain CT scan examination. Age- and sex-matched control subjects comprised a group of comparable patients, none of whom had received ECT, and a second control group of healthy volunteers. Patients had larger ventricle/brain ratios and cortical "atrophy" scores than normal controls, but no association was found between these radiological measures and a previous history of ECT. Hence, the present data are consistent with recent reports that affective disorders may be associated with enlarged brain ventricles, although the clinical significance of such findings remains unclear. In line with previous investigations age correlated significantly with cortical "atrophy" scores and ventricle/brain ratios for all subjects. Statistical tests of correlations between duration of illness, previous psychotropic drug exposure and CT scan appearances were mainly inconclusive.     

CT诊断输尿管梗阻病因分析

目的　探讨CT诊断输尿管梗阻病因的价值。方法　本文收集 17例经多种泌尿系统的检查而未能确诊病因的资料。其中 ,12例经手术病理证实 ,2例经体外震波碎石治疗 ,3例经临床随访证实。结果　单纯性结石 5例 ,炎性狭窄 4例 ,乳头状移行细胞癌 2例 ,输尿管慢性炎症伴结石 1例 ,黄色肉芽肿性慢性肾盂肾炎伴结石 1例 ,右侧异位输尿管开口伴囊肿结石 1例 ,多囊肾伴左肾盂输尿管交界处狭窄 1例 ,左输尿管结核1例 ,乳房癌、直肠癌转移 /或侵犯输尿管各 1例。定位诊断率 10 0 % ,定性诊断率 88 2 4 %。结论　CT做为输尿管梗阻常规检查后的补充检查手段能有效提高病因诊断的正确率。     

Does T2 inversion aid in identifying disc pathologies?

ObjectiveT2 inversion sequence is used in routine radiology practice mainly to heighten contrast resolution within the region to be studied but no evidence exists in current literature to assess it's true efficacy for lumbar disc degeneration. The objective of this study was to analyse T2 inversion and evaluate it's efficacy in assessment of lumbar disc pathology,.Materials and methodsThis retrospective single-centre study included 50 randomly selected patients presenting with back pain and radiculopathy. T2 inversion sequence was obtained in both axial and sagittal planes in addition to routine sequences. All the Magnetic Resonance Imaging (MRI) procedures were performed on 3T. One senior Musculoskeletal (MSK) radiologist, 2 general radiologists and a spinal surgeon blinded to final results reviewed images for the various disc pathologies individually analysing conventional and T2 inversion images. Data was analysed using Fischer's test and Chi² test with a p value of <0.05 considered as significant.ResultsFifty randomly selected patients (mean age was 47.3 years(range 35–55 years) with back pain and radicular symptoms were included. The spectrum of disc pathologies included protrusions, annular fissures, discal cysts and calcified discs. Based on the above findings, T2 inversion sequence is not proved to be an alternative imaging sequence to routine MR imaging sequences for the depiction of various disc pathologies.ConclusionT2 inversion sequence does not increase the depiction of various lumbar disc pathologies in comparison with conventional sequences when used by experienced MSK radiologists. It may highlight abnormalities better for relatively inexperienced readers such as general radiologists and spinal surgeons.     

Methods to address metal artifacts in post-processed CT images – A do-it-yourself guide for orthopedic surgeons

Computed tomography (CT) scans are often used for postoperative imaging in orthopedics. In the presence of metallic hardware, artifacts are generated, which can hamper visualization of the CT images, and also render the study ineffective for 3-D printing. Various solutions are available to minimize metal artifacts, and radiologists can employ these before or after processing the CT study. However, the orthopedic surgeon may be faced with situations where the metal artifacts were not addressed. To counter such problems, we present three do-it-yourself (DIY) techniques that can be used to manage metal artifacts.