To the role of computed tomography in the algorithm of diagnosis of lung cancer

The paper summarizes the results of examination of 100 patients with malignant tumors of the lung. The results of X-ray study, linear tomography, and computed tomography (CT) used in the examination of patients with lung cancer were compared by using as an indicator the following parameters: to make diagnosis of lung cancer, to reveal mediastinal intergrowths, to detect enlarged lymph nodes, pulmonary metastases, and pleural lesions, to obtain information on tumor spread into the chest, to reveal growths into the vascular walls. To evaluate the efficiency of the techniques in solving the above diagnostic tasks, a statistical analysis including the estimation of their accuracy, specificity, and sensitivity was made. Recommendations for examination of patients with lung cancer were drawn up for therapeutic institutions of different types.     

肺脏超声对新生儿呼吸窘迫综合征的诊断价值及肺超声评分的评估价值分析

目的:探讨肺脏超声对新生儿呼吸窘迫综合征(NRDS)的诊断价值,并分析肺超声评分的临床应用价值。方法:本研究选择2017年5月至2018年5月于我院确诊的NRDS患儿45例作为观察组,选择同期于我院就诊的非肺病患儿45例作为对照组,所有患儿均行肺脏超声检查。分析NRDS患儿肺脏超声特征性征象,比较肺脏超声对两组患儿各种征象的检出率,分析肺脏超声对NRDS的诊断价值,比较两组肺超声评分。结果:NRDS患儿全部存在肺实质征象,超声下肺组织回声呈肝样伴支气管充气征,轻度的NRDS患儿于肺脏超声下表现为局灶性的肺实质,且支气管充气征不明显;重度的NRDS患儿于肺脏超声下表现为肺实质范围的进一步扩大,且支气管充气征随病情的加重而愈发明显。观察组肺实质、胸膜线异常、A线消失、弥漫性肺水肿、支气管充气征等征象的检出率显著高于对照组(P0.05),两组B线存在征象的检出率比较无统计学差异(P0.05)。肺实质、胸膜线异常和A线消失三种特征征象同时存在时对NRDS诊断的灵敏度和特异性均为100.00%,肺实质、胸膜线异常和支气管充气征三种特征征象同时存在时对NRDS诊断的灵敏度为80.00%,特异性为100.00%。观察组双肺、左肺、右肺、双侧肺、双肺底肺超声评分均高于对照组(P0.05)。结论:肺脏超声对NRDS的诊断价值较高,且肺超声评分可以评估NRDS患儿的病情严重程度,有助于指导患儿的治疗。     

对比分析四维容积超声及彩色多普勒超声在胎儿肺静脉异位引流诊断中的应用

摘要 目的：对比分析四维容积超声及彩色多普勒超声在胎儿肺静脉异位引流（APVC）诊断中的应用价值。方法：采用回顾性分析方法,2019年1月到2022年1月选择在本院进行诊治的胎儿肺静脉异位引流孕妇60例作为研究对象,都给予四维容积超声及彩色多普勒超声,记录影像学特征并判断诊断价值。结果：在60例孕妇中,彩色多普勒超声检查判断为胎儿肺静脉异位引流51例,诊断敏感性为85.0 %;四维容积超声检查判断为胎儿肺静脉异位引流59例,诊断敏感性为98.3 %,四维容积超声检查对胎儿肺静脉异位引流的诊断敏感性明显高于彩色多普勒超声检查（P<0.05）。彩色多普勒超声检查与四维容积超声检查诊断的特异性都为100.0%。在60例孕妇中,判断为胎儿肺静脉异位引流心上型32例,心下型28例;心上型的肺静脉引流途径为肺静脉-垂直静脉-右上腔静脉22例、肺静脉-垂直静脉-左上腔静脉10例,心下型的肺静脉引流途径为肺静脉-垂直静脉-左头臂静脉-右上腔静脉6例、肺静脉-垂直静脉-门静脉22例。合并心脏畸形32例,合并畸形率为53.3 %;有51例孕妇终止妊娠,9例孕妇继续妊娠,其中8例未经治疗者新生儿期死亡,1例在3月龄死亡。结论：相对于彩色多普勒超声,四维容积超声在胎儿肺静脉异位引流诊断中的应用可提高诊断敏感性,可有效反映肺静脉回流情况,可指导临床进行早期干预。     

The role of transbronchial lung biopsy in the diagnosis of solitary pulmonary nodule

Transbronchial lung biopsy (TBLB) is a well-recognized diagnostic technique in diffuse interstitial lung diseases, but it is not considered to be the first choice in investigation of solitary pulmonary nodules (SPN). The main idea of this study was to increase the sensitivity of bronchoscopy using multiple techniques, especially TBLB, thus to avoid more aggressive diagnostic procedures. The objective of this prospective study was to evaluate the efficacy and safety of TBLB in the diagnosis of SPN, in comparison with other bronchoscopic techniques. Fifty patients with chest x-ray finding consistent with SPN underwent bronchoscopy with bronchial washing, brushing, bronchoalveolar lavage (BAL) and TBLB were included in this study. Thirty-one patients suffered from malignant tumors, while 19 patients had nonmalignant lesions. TBLB achieved overall diagnostic sensitivity of 62%, BAL of 29%, bronchial brushing of 16% and washing of 6%. Combining all techniques together, bronchoscopy had overall sensitivity of 86%. Concerning malignant lesions, TBLB had a sensitivity of 65%, specificity of 100%, and accuracy of 82%. TBLB had a significantly better yield for lesions with a diameter > or = 25 mm than for lesions of < 25 mm (sensitivity of 82% and 53% respectively, p < 0.05). Diagnostic yield improved significantly with the increasing number of specimens (less than 3 specimens: sensitivity 59%, 3 or more specimens: sensitivity 87%, p < 0.05). Complications of TBLB occurred in 2 (4%) patients: 1 incomplete pneumothorax and 1 hemorrhage. According to the results, we conclude that TBLB is an accurate and safe technique for the diagnosis of pulmonary solitary nodule with a diameter equal or greater than 25 mm.     

Role of Transthoracic Lung Ultrasonography in the Diagnosis of Pulmonary Embolism: A Systematic Review and Meta-Analysis

Background

Pulmonary embolism (PE) is a potentially life-threatening condition. Although computed tomography pulmonary angiography (CTPA) is the reference standard for diagnosis, its early diagnosis remains a challenge, and the concerns about the radiation exposures further limit the general use of CTPA. The primary aim of this meta-analysis was to evaluate the overall diagnostic accuracy of transthoracic lung ultrasound (TLS) in the diagnosis of PE.

Methods

PubMed, Web of science, OvidSP, ProQuest, EBSCO, Cochrane Library and Clinicaltrial.gov were searched systematically. The quality of included studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. The sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR) and hierarchical summary receiver operating characteristic (HSROC) curves were used to examine the TS performance. The Bayes analysis was used to calculate the post-test probability of PE. Publication bias was assessed with Deeks funnel plot.

Results

The results indicated that the sensitivity, specificity, PLR and NLR were 0.85 (95% confidence interval (CI), 0.78 to 0.90), and 0.83 (95% CI, 0.73 to 0.90). And the DOR and HSROC were 28.82 (95% CI, 17.60 to 47.21), 0.91(95% CI, 0.88, 0.93).

Conclusions

The present meta-analysis suggested that transthoracic lung ultrasonography is helpful in diagnosing pulmonary embolism. Although the application of transthoracic lung ultrasound may change some patients’ diagnostic processes, it is inappropriate to generally use transthoracic ultrasonography in diagnosing pulmonary embolism currently.     

Accuracy of Lung Ultrasonography versus Chest Radiography for the Diagnosis of Adult Community-Acquired Pneumonia: Review of the Literature and Meta-Analysis

Lung ultrasonography (LUS) is being increasingly utilized in emergency and critical settings. We performed a systematic review of the current literature to compare the accuracy of LUS and chest radiography (CR) for the diagnosis of adult community-acquired pneumonia (CAP). We searched in Pub Med, EMBASE dealing with both LUS and CR for diagnosis of adult CAP, and conducted a meta-analysis to evaluate the diagnostic accuracy of LUS in comparison with CR. The diagnostic standard that the index test compared was the hospital discharge diagnosis or the result of chest computed tomography scan as a “gold standard”. We calculated pooled sensitivity and specificity using the Mantel-Haenszel method and pooled diagnostic odds ratio using the DerSimonian-Laird method. Five articles met our inclusion criteria and were included in the final analysis. Using hospital discharge diagnosis as reference, LUS had a pooled sensitivity of 0.95 (0.93-0.97) and a specificity of 0.90 (0.86 to 0.94), CR had a pooled sensitivity of 0.77 (0.73 to 0.80) and a specificity of 0.91 (0.87 to 0.94). LUS and CR compared with computed tomography scan in 138 patients in total, the Z statistic of the two summary receiver operating characteristic was 3.093 (P = 0.002), the areas under the curve for LUS and CR were 0.901 and 0.590, respectively. Our study indicates that LUS can help to diagnosis adult CAP by clinicians and the accuracy was better compared with CR using chest computed tomography scan as the gold standard.     

Hepatobiliscintigraphy in the diagnosis of obstructive jaundice

The authors show the role of hepatobiliscintigraphy (HBSG) in cholelithiasis as a screening technique in evaluating the patency of the common bile duct, which allows cholecystectomy to be performed if there are normal values, without resorting to additional studies. They have reprospectively analyzed the results of clinical and instrumental studies in 101 patients with cholelithiasis and obstructive jaundice of various etiology in whom the diagnosis was verified by endoscopic cholangiopancreatography (ERCPG). The sensitivity, specificity, and diagnostic efficiency of the scintigraphic technique were 96.5, 36.3, and 86.1%, respectively. It is recommended that invasive diagnostic techniques, such as ERCPG and other direst X-ray contrasting methods, should be used after having a positive result of two techniques: ultrasonography and HBSG (in the above order).     

血清PCT、CRP与sTREM-1在肺癌患者术后肺部感染中表达及其诊断价值分析

目的:探究血清降钙素原(PCT)、C-反应蛋白(CRP)与可溶性人髓系细胞触发受体-1(sTREM-1)在肺癌患者术后肺部感染中表达及其诊断价值。方法:选择2016年2月至2019年10月期间在我院行肺癌根治术的420例肺癌患者作为研究对象,根据术后患者是否发生肺部感染进一步划分为380例未感染组和40例感染组。感染组根据治疗结局进一步划分为29例治疗好转亚组与11例未好转亚组。采用酶联免疫吸附法检测各组的血清PCT、CRP与s TREM-1水平,采用受试者工作特征(ROC)曲线分析血清PCT、CRP和s TREM-1对肺癌患者术后肺部感染的预测价值。结果:与未感染组相比,感染组手术后血清PCT、CRP和s TREM-1水平均明显升高(P0.05)。与治疗好转亚组相比较,治疗未好转亚组手术后以及感染后血清PCT、CRP和s TREM-1水平均明显升高(P0.05)。ROC曲线显示,PCT的曲线下面积(AUC)为0.713,最佳截断值为1.23 ng/mL,灵敏度、特异度分别为0.81、0.79,准确度为0.82;CRP的AUC为0.752,最佳截断值为36.07 mg/L,灵敏度、特异度分别为0.83、0.81,准确度为0.83;s TREM-1的AUC为0.792,最佳截断值为20.58 pg/mL,灵敏度、特异度分别为0.86、0.84,准确度为0.85;PCT、CRP联合s TREM-1预测肺癌患者术后肺部感染的AUC为0.884,灵敏度、特异度分别为0.89、0.91,准确度为0.92。结论:肺癌根治术后肺部感染发生与患者血清PCT、CRP和s TREM-1水平相关,早期联合检测血清PCT、CRP和s TREM-1有助于预测肺癌根治术患者肺部感染发生风险,在肺癌根治术后肺部感染的预测和诊断中具有一定临床价值。     

个体化快速心律失常虚拟介入手术体系的建立与临床应用价值研究

目的:建立个体化快速心律失常虚拟介入手术体系定位手术靶点并分析其临床应用价值。方法:收集2011年1月-2013年1月在我院进行射频消融手术治疗的室性早搏和房室折返性心动过速患者共120例,(其中室性早搏40例,房室折返性心动过速80例),平均年龄40.6±9.7岁,获取数字新电机记录18导体表心电图(ECG)、数字食道调搏图、心脏CT成像原始数据,并记录手术靶点。所有采集心电图和CT数据进行多模式序列识别系统的计算机辅助诊断(CAD)处理,然后再对处理后的数据进行分析。两名心内科医生人工对心电图进行分析定位,并不告知患者的临床资料及射频消融手术最终靶点定位结果,按照室性早搏和房室旁路的诊断定位标准进行诊断,随后两名医师对处理后的心电图进行诊断,再次得出诊断结果,以术中成功消融靶点定位诊断为金标准,分析,个体化快速心律失常虚拟介入手术体系定位手术靶点的特异性、敏感性、阳性预测值,阴性预测值等指标。结果:ECG+CAD组诊断准确度高于单独ECG组,ECG组ROC曲线下面积(Az)=0.742,95%可信区间[0.652-0.832];ECG+CAD组:Az=0.934,95%可信区间[0.882-0.985];ECG+CAD组:精确度0.908;敏感性:0.905;特异性:0.923;阳性预测值:0.818;阴性预测值:0.934,较单独ECG组明显提高。结论:与单独体表心电图定位诊断相比,虚拟介入手术体系显著提高快速心律失常诊靶点定位的准确度,临床应用价值更高。     

Gastric and intestinal scintigraphy in the complex diagnosis of small bowel obstruction

An algorithm has been developed for radiation diagnosis of small bowel obstruction, which involves abdominal X-ray and ultrasound studies at the first stage and radionuclide evaluation of gastrointestinal transit, by using 100-150 ml of aqueous 99mTc-technefite or 99mTc-bromeside solution in a dose of 50-100 MBq (radiation load 0.7-1.4 MeV) per os. The sensitivity, specificity, and diagnostic efficiency of the whole radiation diagnostic complex and each procedure separately were determined by the results of examination in 180 patients with suspected small bowel obstruction, of whom 104 patients were operated on, but obstruction ceased during medical treatment. Inclusion of the radionuclide technique into the diagnostic complex involving plain radiography and ultrasonography was shown to enhance diagnostic efficiency up to 97-98%.     

Radiation diagnosis of Langerhans cell histiocytosis (LCH) of lung

The authors studied the pattern of X-ray changes detectable in the lungs of 41 patients with LCH. The results of classical X-ray study were supplemented by the data of computed tomography, ultrasonography, and 99mTc and 67Ga citrate radioisotopic studies. The diagnostic values of these techniques were compared. X-ray syndromes of changes in the lung in LCH were found to be interstitial, interstitial and granulomatous, tumorous (focal). The authors emphasize the multisystematic character of a lesion, the phasic nature and progression of the disease into fibrosis.     

Assessment of diagnostic accuracy of SanketLife – A wireless,pocket-sized ECG biosensor,in comparison to standard 12 lead ECG in the detection of cardiovascular diseases in a tertiary care setting

BackgroundThe SanketLife is a low cost, portable, pocket sized 12 lead ECG mechanised by SanketLife app running on compatible iOS and Android phones that connect wirelessly via Bluetooth technology to the device.ObjectiveThe current study was conducted to assess the diagnostic accuracy of SanketLife ECG in comparison to standard 12 lead ECG (GE-2000) in detection of cardiovascular diseases.Research design and methodsThis was a prospective diagnostic test accuracy trial conducted in outpatient settings of a tertiary cardiac care centre in India. A total of 100 patients, attended cardiology OPD, were included in the study. Consecutive ECGs were taken by 12 lead standard ECG as well as by SanketLife ECG. Diagnostic accuracy variables such as sensitivity, specificity, negative and positive predictive value, negative and positive likelihood ratios were estimated. Ethical permission was taken from the Institutional ethical committee.Results & conclusionThe analysis showed a high degree of agreement and accuracy of SanketLife in detecting major cardiovascular conditions (Major Minnesota codes) such as Left and right bundle branch block, ST-segment elevation and ST-segment depression, AV conduction block. SanketLife showed high sensitivity (98.15%) and specificity (100%) in diagnosing major cardiovascular conditions.     

Detection of Rib Metastases in Patients with Lung Cancer: A Comparative Study of MRI,CT and Bone Scintigraphy

We retrospectively investigated the imaging findings of bone scintigraphy, chest CT and chest MRI in 55 cases of lung cancer. The sensitivity, specificity and accuracy of the detection of rib metastases were compared between imaging modalities on both a per-lesion and a per-patient basis. On a per-lesion basis, MRI sensitivity and accuracy were significantly higher than that of bone scintigraphy and CT (P<0.05). The sensitivities, specificities, and accuracy levels between CT and bone scintigraphy did not differ on either a per-lesion or per-patient basis (P>0.05). MRI appears to be superior for the detection of ribs metastases in lung cancer.     

Venous volume displacement plethysmography: Its diagnostic value in deep venous thrombosis as determined by receiver operator characteristic curves

The pitfall of several reviews of noninvasive venous assessment has been the expression of the test data solely in terms of diagnostic accuracy (the number of correct tests in ratio to all tests performed), where results of a test will vary according to disease prevalence. The advantages of receiver operator characteristic curve analysis are twofold: (1) it describes the dynamic relationship between sensitivity (the ratio of the number of true positive tests to the patients with deep venous thrombosis) and specificity (the ratio of true negative tests to the number of patients with no deep venous thrombosis) independent of disease prevalence; and (2) the threshold criteria that defines a positive test can be set by the best balance between sensitivity and specificity and then applied to a given patient population for its diagnostic accuracy. Venous volume plethysmography is a widely used, simple and rapid method. It was compared to the "gold standard" of phlebography in a prospective blind study of 70 limbs that were clinically suspect of having deep venous thrombosis (DVT). Venous volume displacement plethysmography was defined objectively by three quantitative parameters: (1) maximum venous outflow, (2) integer ratio, and (3) segmental venous capacitance ratio. The DVT (22 to 70 positive phlebograms) was divided by anatomic location into either calf vein DVT or proximal DVT (popliteal vein or above). By combining these three parameters, a balance between sensitivity and specificity was obtained to provide a rapid, objective method for screening patients with suspected DVT.     

x线断层容积成像技术在肺动脉畸形中的应用

目的：通过与常规x线胸片比较,探讨胸部x线断层容积成像技术在肺动脉畸形中的应用价值。方法：对20例临床及x线平片怀疑肺动脉畸形者,进一步进行胸部x线断层容积成像检查。其中11例被明确诊断为肺动脉畸形。以CT或超声心动结果为标准,对比两种图像对肺动脉畸形的明确诊断率,分析对比该11例患者的胸部x线断层容积成像图片和普通x线胸片,评价两种方法所获得的图像质量和图片优秀率。结果：20例疑似患者中,11例被CT或超声心动确诊为肺动脉畸形,其x线断层容积成像图片和普通x线胸片经主管技师和副主任医师双盲判读,x线断层容积成像11例均获明确诊断（100％）,普通x线胸片明确诊断2例（18％）,诊断准确率有明显差异（P=0．O001）。容积断层成像优质图像为10例,占总数的90．91％;良好1例,差为0例。11例x片中优秀7例,占总数的63．63％,其中良好3例,差1例。两种图像优秀率比较差异有统计学意义（P=0．0001）。结论：x线断层容积成像技术对肺动脉畸形的图像优秀率和诊断准确率均高于x线平片,对病变的显示更加清晰、立体,提高诊断准确率和客观性,具有重要的临床诊断价值。     

The Supraclavicular Fossa Ultrasound View for Central Venous Catheter Placement and Catheter Change Over Guidewire

The supraclavicular fossa ultrasound view can be useful for central venous catheter (CVC) placement. Venipuncture of the internal jugular veins (IJV) or subclavian veins is performed with a micro-convex ultrasound probe, using a neonatal abdominal preset with a probe frequency of 10 Mhz at a depth of 10-12 cm. Following insertion of the guidewire into the vein, the probe is shifted to the right supraclavicular fossa to obtain a view of the superior vena cava (SVC), right pulmonary artery and ascending aorta. Under real-time ultrasound view, the guidewire and its J-tip is visualized and pushed forward to the lower SVC. Insertion depth is read from guidewire marks using central venous catheter. CVC is then inserted following skin and venous dilation. The supraclavicular fossa view is most suitable for right IJV CVC insertion. If other insertion sites are chosen the right supraclavicular fossa should be within the sterile field. Scanning of the IJVs, brachiocephalic veins and SVC can reveal significant thrombosis before venipuncture. Misplaced CVCs can be corrected with a change over guidewire technique under real-time ultrasound guidance. In conjunction with a diagnostic lung ultrasound scan, this technique has a potential to replace chest radiograph for confirmation of CVC tip position and exclusion of pneumothorax. Moreover, this view is of advantage in patients with a non-p-wave cardiac rhythm were an intra-cardiac electrocardiography (ECG) is not feasible for CVC tip position confirmation. Limitations of the method are lack of availability of a micro-convex probe and the need for training.     

Diagnostic Accuracy of CT-Guided Transthoracic Needle Biopsy for Solitary Pulmonary Nodules

To evaluate the diagnostic accuracy of computed tomography (CT)-guided percutaneous lung biopsy for solitary pulmonary nodules. Three hundred and eleven patients (211 males and 100 females), with a mean age of 59.6 years (range, 19–87 years), who were diagnosed with solitary pulmonary nodules and underwent CT-guided percutaneous transthoracic needle biopsy between January 2008 and January 2014 were reviewed. All patients were confirmed by surgery or the clinical course. The overall diagnostic accuracy and incidence of complications were calculated, and the factors influencing these were statistically evaluated and compared. Specimens were successfully obtained from all 311 patients. A total of 217 and 94 cases were found to be malignant and benign lesions, respectively, by biopsy. Two hundred and twenty-five (72.3%) carcinomas, 78 (25.1%) benign lesions, and 8 (2.6%) inconclusive lesions were confirmed by surgery and the clinical course. The diagnostic accuracy, sensitivity, and specificity of CT-guided percutaneous transthoracic needle biopsy were 92.9%, 95.3%, and 95.7%, respectively. The incidences of pneumothorax and self-limiting bleeding were 17.7% and 11.6%, respectively. Taking account of all evidence, CT-guided percutaneous lung biopsy for solitary pulmonary nodules is an efficient, and safe diagnostic method associated with few complications.     

Pulmonary perfusion in supine and prone positions: an electron-beam computed tomography study.

Acute respiratory distress syndrome is characterized by alterations in the ventilation-perfusion ratio. Present techniques for studying regional pulmonary perfusion are difficult to apply in the critically ill. Electron-beam computed tomography was used to study the effects of prone positioning on regional pulmonary perfusion in six healthy subjects. Contrast-enhanced sections were obtained sequentially in the supine, prone, and (original) supine positions at full inspiration. Regions of interest were placed along the nondependent to dependent axis and relative perfusion calculated. When corrected for the redistribution of lung parenchyma, a gravitational gradient of pulmonary perfusion existed in both supine and prone positions. The distribution of perfusion between the supine or prone positions did not differ, but data analysis using smaller regions of interest demonstrated marked heterogeneity of perfusion between anatomically adjacent regions of lung. The distribution of lung parenchyma was more uniform in the prone position. Gravity was estimated to be responsible for 22-34% of perfusion heterogeneity in the supine and 27-41% in the prone positions. These data support the hypothesis that factors other than gravity may be at least as important in determining the distribution of pulmonary perfusion in humans. The influence of nongravitational factors may not be detectable if techniques that sample large tissue volumes are employed.     

Marked differences between prone and supine sheep in effect of PEEP on perfusion distribution in zone II lung.

The classic four-zone model of lung blood flow distribution has been questioned. We asked whether the effect of positive end-expiratory pressure (PEEP) is different between the prone and supine position for lung tissue in the same zonal condition. Anesthetized and mechanically ventilated prone (n = 6) and supine (n = 5) sheep were studied at 0, 10, and 20 cm H2O PEEP. Perfusion was measured with intravenous infusion of radiolabeled 15-microm microspheres. The right lung was dried at total lung capacity and diced into pieces (approximately 1.5 cm3), keeping track of the spatial location of each piece. Radioactivity per unit weight was determined and normalized to the mean value for each condition and animal. In the supine posture, perfusion to nondependent lung regions decreased with little relative perfusion in nondependent horizontal lung planes at 10 and 20 cm H2O PEEP. In the prone position, the effect of PEEP was markedly different with substantial perfusion remaining in nondependent lung regions and even increasing in these regions with 20 cm H2O PEEP. Vertical blood flow gradients in zone II lung were large in supine, but surprisingly absent in prone, animals. Isogravitational perfusion heterogeneity was smaller in prone than in supine animals at all PEEP levels. Redistribution of pulmonary perfusion by PEEP ventilation in supine was largely as predicted by the zonal model in marked contrast to the findings in prone. The differences between postures in blood flow distribution within zone II strongly indicate that factors in addition to pulmonary arterial, venous, and alveolar pressure play important roles in determining perfusion distribution in the in situ lung. We suggest that regional variation in lung volume through the effect on vascular resistance is one such factor and that chest wall conformation and thoracic contents determine regional lung volume.     

Diagnosis and typing of lung carcinomas by cytopathologic methods. A review of 108 cases

A correlative review was made of the type of cytology specimens (sputum, bronchial washing and bronchial brushing) together with the corresponding histopathologic specimens of 108 patients. One hundred patients had primary pulmonary carcinomas diagnosed histopathologically (84) or clinically (16); 5 had carcinomas metastatic to the lungs and 3 had apparently false-positive cytologic results for lung cancer. The correlative review was used to determine the diagnostic reliability of pulmonary cytopathologic techniques in the detection and classification of lung carcinomas (i.e., the sensitivity and accuracy). The overall sensitivities of sputum, bronchial washing and bronchial brushing cytology were 60%, 66% and 77%, respectively (p less than 0.05). Bronchial brushing had a higher sensitivity (80%) for peripheral and metastatic lesions than did sputum (37%) or bronchial washing (60%). The overall accuracies of sputum, bronchial washing and bronchial brushing cytology were 79%, 75% and 76%, respectively, which is not statistically different. Regardless of the sampling methods, cytologic typing of squamous-cell and small-cell carcinomas was highly accurate but was less satisfactory for the other types of lung carcinomas. In the 16 cases in which endoscopic biopsies were either not attempted or gave negative results, one or more pulmonary cytologic specimens showed malignant cells. It is concluded that: (1) pulmonary cytopathologic techniques have excellent sensitivity and accuracy in the diagnosis of lung carcinomas; (2) they may establish the diagnosis of pulmonary carcinomas when endoscopic biopsies give negative results; and (3) they are particularly helpful in cases in which endoscopic biopsies suffer from a low yield (peripheral lesions) or create a considerable danger to the patients (iatrogenic hemorrhage).