CT appearances of rounded atelectasis

Five patients examined with CT bad lesions fulfilling criteria for a diagnosis of rounded atelectasis (RA) and these were managed with out biopsy. In three patients unsuspected contralateral lesions were identifled as RA variants, and one of these was biopsied at thoracotomy and proved to be benign. All patients remain well at 6–22 months follow-up. We concur with recent reports that there is a spectrum of CT appearances of RA and that even atypical lesions seldom need further investigation. We also suggest that the appearances of some atypical lesions add support for the fibrosing theory of pathogenesis of RA.     

老年肺不张患者的纤维支气管镜检查(附425例纤支镜检查分析)

目的 :对 44 0例老年肺不张探讨。方法 :经纤支镜活检、刷检、涂片、病理确诊。结果 :肺癌发病率最高 ,经纤支镜活检确诊 2 2 0例 ,胸水找到癌细胞 15例 ,共占 5 3 4 %。炎症 16 4例 ,占 37 2 %,肺结核 37例占 8 4 %,支气管结石 4例 ,占1%。结论 :目前临床上纤支镜检查仍为明确肺不张病因的主要手段 ,尤其是临床治疗效果不佳时 ,早期行纤支镜检查获得病理结果非常重要。     

纤维支气管镜检查对老年肺不张的病因诊断

目的　探讨老年肺不张的病因及纤支镜检查在明确病因诊断中的作用。方法　经胸部Ｘ线或ＣＴ证实为肺不张的老年患者２４３ 例，行纤支镜检查并取活检，刷检及抗酸杆菌检查。结果　肺癌１５８ 例（６５．０％ ） ，其中鳞癌１２１ 例，未分化癌２１ 例，腺癌１６ 例，慢性炎症６２ 例（２６．７％ ），支气管内膜结核１５ 例（６．２ ％ ） ，纵隔淋巴瘤３ 例（１．２ ％ ） ，支气管扩张并血块阻塞２ 例（０．８％ ）。结论　老年肺不张多由肿瘤所致，纤支镜检查是明确病因诊断的重要方法。老年肺不张一旦发现，应尽快行纤支镜检查。     

Linear Atelectasis in the Lingula as a Diagnostic Feature of Left Lower Lobe Collapse: Nordenström's Sign

Collapse of the left lower lobe is sometimes accompanied by linear atelectasis in the lingula. The lingular atelectasis may be more readily apparent than conventional signs of left lower collapse. The mechanism of this association as first described by Nordenström is discussed and its value as a diagnostic sign emphasised.     

Imaging findings of renal cell carcinoma

There are many imaging modalities used in the diagnosis of renal cell carcinoma, the most common cancer of the kidney, which accounts for approximately 2–3% of adult malignancies. Early detection of this tumor with the correct diagnostic approach using various cross-sectional imaging is very important, as are the clinical and laboratory findings. Familiarity with the spectrum of imaging findings of renal cell carcinoma will enable clinicians to consider appropriate treatment for patients and eliminate unnecessary further imaging studies.     

胃肿瘤CT灌注成像的临床研究

Objection: The purpose of this study is preliminarily to discuss stomach perfusion imaging technique with Multi-slice CT and its clinical application value in stomach neoplasm. Methods: Fifteen patients with known stomach neoplasm performed perfusion imaging with 4 or 16 slice CT. Performing peffusion imaging in central slice of neoplasm, using CT cine scan, slice thick 10 mm/2i; with high pressure syringe, injecting quickly from right elbow-front vein, dosage 45-50 mL, injec-tion rate 3.5-4.0 mL/s, scanning delay time 5 s, scanning total time 45 s. We performed perfusion CT post-processing using pancreatic mode of perfusion CT software. Blood flow (BF), blood volume (BV), mean transit time (MTT), and permeability surface (PS) of gastric wall and tumor were computed for every case. Results: BF, BV, MTT and PS of gastric tumor were 116.68±90.09 mL/(min .100 g), 9.57±8.12 mL/100 g, 10.07± 7.74 s, 20.78±19.68 mL/ (min .100 g), respectively. The P values for each CT perfusion parameters between gastdc tumor and normal gastric wall were 0.001,0.021, 0.155 and 0.031,respectively. Conclusion: Perfusion CT can provide hemodynamics of gastdc tumors and play a key role in the diagnosis of gastric tumors. It's clinical application prospect will be fully broad.     

Experience converting an RT department to full CT simulation: Technical issues identified during commissioning of a wide‐bore scanner

The advent of CT scanners with larger bore sizes have offered the potential for radiotherapy departments to undertake the majority or all treatment planning simulation via CT. Wide‐bore scanners can present some unique issues when being commissioned for clinical use. During the process of converting a radiotherapy department to full CT simulation, several issues regarding images produced by a wide‐bore scanner were identified. These were investigated by using electron density and image resolution phantoms. It was found that the reconstruction algorithm used by the scanner of interest for extended field of view (FOV) imaging, combined with the extended X‐ray source‐to‐detector distance, influenced the resolution and quality of images. The reconstruction technique influenced the relationship between electron density and CT number with distance from the scanner axis, leading to image artefacts. A variation of 400 CT units is seen for cortical bone across the scanner FOV, with smaller variations for water and breast tissue. It is anticipated that this variation will impact on tissue delineation, and subsequent dose calculation would become questionable should beams pass through large areas of artefact. Image resolutions of 0.5 and 0.3 line‐pairs per millimetre (lp/mm) were achievable in the primary and extended FOV regions respectively. Several aspects of image production with a wide‐bore scanner that can influence imaging for radiotherapy treatment planning have been highlighted. Departments should be mindful of these issues when using a GE Lightspeed wide‐bore scanner and should consider how scanner settings should be optimised for the use of images in treatment planning.     

CT appearances of hydatid disease at various locations

Hydatid disease has characteristic imaging features on CT, which allow accurate preoperative diagnosis in most cases. However, when it occurs at unusual locations the diagnosis is often difficult, especially as the imaging appearance varies at different sites. In this article we have presented a pictorial review of the CT features of disease due to Echinococcus granulosus at various sites in the human body.     

The implementation of diagnostic reference levels to Australian radiology practice

At the present time, there is no national surveillance of the increasing ionising radiation dose to the population from diagnostic imaging procedures. As the number of procedures undertaken is increasing, it is expected that the population dose will also increase. A substantial component of that contribution is from multi-detector computed tomography (MDCT) systems. The Australian Radiation Protection & Nuclear Safety Agency (ARPANSA) estimates that the growth in MDCT scans, based on Medicare Benefits Schedule data, is increasing at approximately 9% per annum, with over 2 million MDCT scans being performed in 2009. The caput effective dose (mSv) from this modality is expected to be approaching 1.2 mSv per annum. If current dose-detriment models are accurate, the risk of induction of carcinogenic detriment from current MDCT scanning patterns is a significant public health issue that requires a concerted and ongoing response. For the application of ionising radiation in medicine, the International Commission on Radiological Protection recommends the conservative philosophy of Justification and Optimisation via the measurement of 'Diagnostic Reference Levels' to limit the potential overexposure of patients and decrease the overall population burden. The Australian government has commissioned ARPANSA to survey, calculate and construct representative national diagnostic reference levels for diagnostic imaging modalities that use ionising radiation. This will be achieved in close consultation with the professional organisations who represent the professionals responsible for the use of ionising radiation in diagnostic imaging.     

Toward radiomics for assessment of response to systemic therapies in lung cancer

This editorial comment explains recent developments in radiomics regarding the use of quantitative imaging biomarkers to predict lung cancer sensitivity to a variety of cancer therapies. Tumor response assessment has been a crucial component guiding cancer treatment. Evaluation of treatment response was standardized and classically based on measuring changes in tumor lesion size. Recent breakthroughs in artificial intelligence pave the way for the use of radiomics in tumor response assessment. Such objective techniques would bring a remarkable transformation to conventional methods, which can be inherently subjective. Successful implementation of these technologies would allow for faster and more accurate predictions of treatment efficacy, which will be critical to the advancement of personalized medicine.     

18FDG PET - CT中SUV值对胰腺肿瘤鉴别诊断的作用

目的 回顾性分析胰腺良恶性病变在PET -CT双时相显像中摄取18FDG的变化,寻找PET显像中最大SUV的诊断界值,以探讨其对胰腺良恶性病变诊断与鉴别诊断的临床应用价值.方法 2006年9至2010年9月118例胰腺良恶性病变患者.①胰腺癌患者65例,24例有病理或细胞学诊断,41例仅有影像学和临床诊断,并经临床和影...     

Paediatric CT imaging trends in Australia

Introduction: The use of CT has rapidly increased since its introduction. Although an important medical tool for diagnosis and treatment, CT is recognised as being among the highest contributors to population radiation exposure. As the risks associated with exposure are higher for children than for adults, this study assessed the impact of paediatric CT in Australia by analysing imaging trends. Methods: CT imaging trends were derived from Medicare data. Comparable data from a dedicated paediatric hospital (Royal Children's Hospital Melbourne (RCH)) were analysed to determine the validity of utilising Medicare statistics in the younger age groups. The resulting trends reflect the situation for paediatric CT imaging in Australia. Results: In 2009, 2.1 million CT services were billed to Medicare in Australia for children and adults. The average annual growth in the number of CT services provided since 1994 was 8.5%, compared with population growth of 1.4%. Comparison of RCH and Medicare data revealed that only one third of paediatric CT imaging is captured by Medicare. Combining the data sets showed that over the last 20 years, there has been an average annual increase of 5.1% in the CT imaging rate for 0 to 18‐year‐olds. However, in recent years, growth in the imaging rate for 11 to 18‐year‐olds has slowed, while for 5 to 10‐year‐olds the imaging rate has declined. Conclusions: The significant growth in CT services is attributable to increased demand from the adult demographic. Conversely, increases in the imaging rate for paediatric patients have slowed overall. In fact, for some age groups the rate has fallen.     

肾脏肿瘤影像学诊断

作者报道Ｘ线静脉及逆行肾盂造影、肾动脉造影、Ｂ超显像、ＣＴ扫描对４１例肾脏肿瘤的诊断与手术、病理对照结果。静脉和逆行肾盂造影诊断正确率为８８．２％（３０／３４），Ｘ线肾动脉造影诊断正确率为１００．０％（４／４），Ｂ超诊断正确率为８９．５％（３４／３８），ＣＴ扫描诊断正确率为９６．６％（２８／２９）．作者分别对Ｘ线、Ｂ超、ＣＴ对肾脏肿瘤的影像诊断进行讨论，目的在于提高肾脏肿瘤术前诊断水平。     

Right atrial angiosarcoma and electrocardiogramgated cardiac computed tomography： a case report

Primary cardiac tumors are quite rare and most of these tumors are benign. In this report, a patient presented with chest distress and shortness of breath after activity. Echocardiography of other hospital showed a hyperechoic right atrial mass. Electrocerdiogram-gated cardiac computed tomography (ECG-Gated CT) of our hospital provided accurate information about the site and extent of the tumor, and the involvement of neighboring structures, even about the malignant nature of the lesion. The pathological study indicated angiosarcorna. The role of ECG-Gated CT in the assessment of cardiac masses and tumors was discussed. Cardiac tumors are extremely rare and can be divided into benign and malignant lesions. Myxomas are the most common type of cardiac benign tumor, while angiosarcomas are the most common type of cardiac malignant tumor.Imaging studies play an important role in the diagnosis of cardiac angiosarcomas. Echocardiogram, computed tomography (CT) and magnetic resonance imaging (MRI) are the most common imaging studies for tumors evaluation. However, the precise tumor location is often difficult to evaluate precisely on the basis of two-dimensional source images. We conducted ECG-gated cardiac CT examination with 3D reconstruction for preoperative assessment in a patient with a angiosarcorna arising in the right atrium.     

SPECT/CT融合显像对脊柱和肋骨单发浓聚灶的鉴别诊断价值

[目的]评价SPECT配置2.5mA X射线球管装置系统融合显像对脊柱、肋骨单发浓聚灶良恶性病变的鉴别诊断价值。[方法]选取在全身骨显像中表现为脊柱、肋骨单发浓聚灶的98例恶性肿瘤患者,同时行SPECT配置2.5mA X射线球管装置系统融合显像。并以CT、MRI结果或6-12个月的随访作为最终临床诊断结果,分析全身骨显像和SPECT配置2.5mA X射线球管装置系统融合显像的鉴别诊断效能。[结果]SPECT配置2.5mA X射线球管装置系统融合显像诊断单发浓聚灶骨转移的敏感性84.21%,特异性91.67%,准确性88.78%,阳性预测值86.49%,阴性预测值90.16%。全身骨显像诊断单发浓聚灶骨转移的敏感性60.53%,特异性71.67%,准确性67.35%,阳性预测值57.50%,阴性预测值74.14%。二者敏感性相比差异有统计学意义（P〈0.05）,特异性和准确性差异均有显著统计学意义（P〈0.01）。[结论]SPECT配置2.5mA X射线球管装置系统融合显像可提高对脊柱和肋骨单发浓聚灶良恶性病变的鉴别诊断能力。     

Opaque maxillary antrum: A pictorial review

The demonstration of an opaque antrum on a plain radiograph or cross‐sectional imaging leads to consideration of an extensive differential diagnosis. Relevant clinical details narrow the differential and include the patient's age, signs and symptoms, a history of recent trauma, prior surgery or dental treatment. Computed tomography remains the most useful technique in coming to a specific diagnosis. Magnetic resonance imaging adds specificity in a few selected situations and is required in conjunction with CT in the staging of malignant tumours.     

Evaluation of inter-fraction prostate motion using kilovoltage cone beam computed tomography during radiotherapy

Aims

The success of delivering the prescribed radiation dose to the prostate while sparing adjacent sensitive tissues is largely dependent on the ability to accurately target the prostate during treatment. Kilovoltage cone beam computed tomography (CBCT) imaging can be used to monitor and compensate for inter-fraction prostate motion, but this procedure increases treatment session time and adds incidental radiation dose to the patient. We carried out a retrospective study of CBCT data to evaluate the systematic and random correction shifts of the prostate with respect to bones and external marks.

Materials and methods

A total of 449 daily CBCT studies from 17 patients undergoing intensity-modulated radiotherapy (IMRT) for localised prostate cancer were analysed. The difference between patient set-up correction shifts applied by radiation therapists (via matching prostate position in CBCT and planning computed tomography) and shifts obtained by matching bony anatomy in the same studies was used as a measure of the daily inter-fraction internal prostate motion.

Results

The average systematic and random shifts in prostate positions, calculated over all fractions versus only 10 fractions, were not found to be significantly different.

Discussion

The measured prostate shifts with respect to bony anatomy and external marks after the first 10 imaging sessions were shown to provide adequate predictive power for defining patient-specific margins in future fractions without a need for ongoing computed tomography imaging. Different options for CBCT imaging schedule are proposed that will reduce the treatment session time and imaging dose to radiotherapy patients while ensuring appropriate prostate cover and normal tissue sparing.     

Lymphangioma: Imaging diagnosis

Lymphangiomas are congenital malformations of the lymphatics that are curable by extirpation. Accurate delineation of lesion extension is important for pre-operative diagnosis, surgical planning, and assessing recurrence. The radiologic findings were retrospectively evaluated to determine the imaging appearance of these benign tumours. The plain radiographs, barium meal, ultrasound, CT, and MR images of 18 patients with one or more pathologically proved lymphangiomas were reviewed. Plain radiography and barium study showed masses displacing adjacent organs. Ultrasound examination showed uni- or multilocular cystic masses with smooth, thin or irregular, thick walls. Enhancement of the cyst wall was variable on CT and MR studies. The CT density of the fluid ranged from ?4 to 34 HU depending on the lipid content and the presence of haemorrhage. The cysts were isointense to muscle on T1 -weighted and hyperintense to fat on T2-weighted MR images. The MR imaging delineated the tumour lesion extension more clearly than ultrasound and CT scans. Ultrasound, CT, and MR imaging are valuable for evaluating lymphangiomas. Magnetic resonance imaging allows accurate determination of lesion extension.     

Bilateral spontaneous adrenal haemorrhage complicating acute pancreatitis

Bilateral adrenal haemorrhage is an event that mandates prompt diagnosis and treatment to prevent primary adrenocortical insufficiency and potential death. Presentation can be non‐specific and incidentally diagnosed with imaging alone, primarily CT. We present a case of acute pancreatitis with spontaneous bilateral adrenal haemorrhage and briefly discuss imaging and treatment implications.