SURG-32. A NOVEL MACHINE LEARNING APPROACH FOR MODELING THE PREDICTIVE VALUE OF COMORBIDITY INDICES IN PITUITARY SURGERY

Although pituitary adenomas (PAs) are common intracranial tumors, literature evaluating the utility of comorbidity indices for predicting perioperative complications in patients undergoing pituitary surgery remains limited, thereby hindering the development of complex models that aim to identify high-risk patient populations. Accordingly, we utilized comparative modeling strategies to evaluate the predictive validity of various comorbidity indices and combinations thereof in predicting key pituitary surgery outcomes. The Nationwide Readmissions Database was used to identify patients who underwent transsphenoidal pituitary tumor operations (n=19,653) in 2016-2017. Patient frailty was assessed using the Johns Hopkins Adjusted Clinical Groups (JHACG). Charlson Comorbidity Index (CCI) and Elixhauser Comorbidity Index (ECI) were calculated for each patient. Five sets of generalized linear mixed-effects models were developed, using 1) Frailty, 2) CCI, 3) ECI, 4) Frailty+CCI, or 5) Frailty+ECI as the primary predictor. Complications investigated included inpatient mortality, non-routine discharge (e.g., to locations other than home) , length of stay (LOS) within the top quartile, cost within the top quartile, and one-year readmission rates. Postoperative mortality occurred in 73 patients (0.4%), one year readmission was reported in 2,994 patients (15.2%),and non-routine discharge occurred in 2,176 (11.1%) patients. The mean adjusted all-payer cost for the procedure was $25,553.85±$26,518.91 (Top Quartile: $28,261.20) and mean LOS was 4.8 days±7.4 days (Top Quartile: 5.0 days). The model using frailty+ECI as the primary predictor consistently outperformed other models, with statistically significant p-values as determined by comparing their AUCs, for most complications. For prediction of mortality, however the Frailty+ECI model (AUC:0.831) was not better than the ECI model alone (AUC:0.831;p=0.95). For prediction of readmission the Frailty+ECI model (AUC:0.617) was not better than the frailty model alone (AUC:0.606;p=0.10) or the Frailty+CCI model (AUC:0.610;p=0.29). Knowledge gained from these models may help neurosurgeons identify high-risk patients requiring additional clinical attention or specific resource utilization prior to surgical planning.

From white to blue light: evolution of endoscope-assisted intracranial tumor neurosurgery and expansion to intraaxial tumors

OBJECTIVE

Intraoperative use of the endoscope to assist in visualization of intracranial tumor pathology has expanded with increasing surgeon experience and improved instrumentation. The authors aimed to study how advancements in endoscopic technology have affected the evolution of endoscope use, with particular focus on blue light-filter modification allowing for discrimination of fluorescent tumor tissue following 5-ALA administration.

METHODS

A retrospective analysis of patients undergoing craniotomy for tumor resection at a single institution between February 2012 and July 2021 was performed. Patients were included if the endoscope was used for diagnostic tumor cavity inspection or therapeutic assistance with tumor resection following standard craniotomy and microsurgical tumor resection, with emphasis on those cases in which blue light endoscopy was used. Medical records were queried for patient demographics, operative reports describing the use of the endoscope and extent of resection, associations with tumor pathology, and postoperative outcomes. Preoperative and postoperative MR images were reviewed for radiographic extent of resection.

RESULTS

A total of 52 patients who underwent endoscope-assisted craniotomy for tumor were included. Thirty patients (57.7%) were men and the average age was 52.6 ± 16.1 years. Standard white light endoscopes were used for assistance with tumor resection in 28 cases (53.8%) for tumors primarily located in the ventricular system, parasellar region, and cerebellopontine angle. A blue light endoscope for detection of 5-ALA fluorescence was introduced into our practice in 2014 and subsequently used for assistance with tumor resection in 24 cases (46.2%) (intraaxial: n = 22, extraaxial: n = 2). Beyond the use of the surgical microscope as the primary visualization source, the blue light endoscope was used to directly perform additional tumor resection in 19/21 cases as a result of improved fluorescence detection as compared to the surgical microscope. No complications were associated with the use of the endoscope or with additional resection performed under white or blue light visualization.

CONCLUSIONS

Endoscopic assistance to visualize intracranial tumors had previously been limited to white light, assisting mostly in the visualization of extraaxial tumors confined to intraventricular and cisternal compartments. Blue light-equipped endoscopes provide improved versatility and visualization of 5-ALA fluorescing tissue beyond the capability of the surgical microscope, thereby expanding its use into the realm of intraaxial tumor resections.

Complementary and Alternative Medicine for the Treatment of Gliomas: Scoping Review of Clinical Studies, Patient Outcomes, and Toxicity Profiles

INTRODUCTION

Complementary and alternative medicine (CAM) are highly used among those diagnosed with glioma. Further research is warranted, however, as it remains important to clearly delineate CAM practices that are unproven, disproven, or promising for future research and implementation.

METHODS

A systematic review was conducted to identify all articles that investigated the effect of any CAM therapy on survival of patients with newly diagnosed or recurrent glioma.

RESULTS

Eighteen papers and 4 abstracts pertaining to the effects of ketogenic diet (4), antioxidants (3), hyperbaric oxygen (4), cannabinoids (2), carbogen and nicotinamide (3), mistletoe extract (2), hypocupremia and penicillamine (1), and overall CAM use (3) on overall and progression-free survival in patients with low- and high-grade glioma were identified (Levels of Evidence I-IV). Ketogenic diets, hyperbaric oxygen therapy, and cannabinoids appear to be safe and well tolerated by patients; preliminary studies demonstrate tumor response and increased progression-free survival and overall survival when combined with standard of care therapies. Antioxidant usage exhibit mixed results perhaps associated with glioma grade with greater effect on low-grade gliomas; vitamin D intake was associated with prolonged survival. Conversely, carbogen breathing and hypocupremia were found to have no effect on the survival of patients with glioma, with associated significant toxicity. Most modalities under the CAM umbrella have not been appropriately studied and require further investigation.

CONCLUSIONS

Despite widespread use, Level I or II evidence for CAM for the treatment of glioma is lacking, representing future research directions to optimally counsel and treat glioma patients.

Nonindex Readmission After Ruptured Brain Aneurysm Treatment Is Associated with Higher Morbidity and Repeat Readmission

BACKGROUND

Aneurysmal subarachnoid hemorrhage (aSAH) requires complex multidisciplinary care. After initial treatment (index hospital), readmission to a different hospital (nonindex) can compromise quality of care, resulting in increased morbidity. We aimed to evaluate factors associated with nonindex readmission and evaluate association of nonindex hospital readmission on outcomes in patients with ruptured aneurysm.

METHODS

Readmissions within 90 days after aSAH treatment were identified in the 2010-2014 Nationwide Readmissions Database. Multivariable logistic regression identified patient and hospital characteristics associated with nonindex readmission. Separate multivariable models determined increased morbidity or risk of second readmission for nonindex readmissions.

RESULTS

A total of 9254 patients who underwent treatment of ruptured aneurysms from 2010 to 2014 were identified. Of these, 1985 (21.5%) were readmitted within 90 days. Three hundred and fifty-five of these readmissions (17.9%) occurred to nonindex hospitals. Patients that were discharged to a skilled nursing or other facility (odds ratio [OR], 1.70; 95% confidence interval [CI], 1.27-2.28]) had higher odds of nonindex readmission, whereas patients with private insurance were associated with lower odds of nonindex readmission (OR, 0.65; 95% CI, 0.46-0.92). Patients readmitted to a nonindex (vs. index) hospital were associated with increased likelihood of major complications (OR, 1.71; 95% CI, 1.18-2.48) and second readmissions (OR, 1.51; 95% CI, 1.17-1.96).

CONCLUSIONS

After treatment of a ruptured cerebral aneurysm, 17.9% of readmissions occurred at a nonindex hospital. These patients were at increased risk for major complications or subsequent readmissions, which may be because of care fragmentation. Interventions aimed at improving continuity of care may reduce higher morbidity associated with nonindex readmission.

Bilateral Vertebral Artery Occlusion After Cervical Spine Fracture Dislocation

BACKGROUND

Vertebral artery injury is known to potentially occur in conjunction with blunt cervical spine trauma. Rarely, these injuries present bilaterally as complete occlusions. Twelve cases of bilateral vertebral artery occlusions after closed cervical spine trauma have been described in the reported data, nearly all of which demonstrated signs and symptoms of vertebrobasilar insufficiency and ischemia.

CASE DESCRIPTION

Our patient presented after a traumatic C5-C6 flexion-distraction injury that had resulted in bilateral locked facets and spinal cord injury and bilateral vertebral artery occlusions at the V1 segment. However, our patient did not show any cranial symptoms despite his neurovascular injury.

CONCLUSIONS

We present our patient's case as a rare illustration of a bilateral vertebral artery occlusion after blunt cervical spine trauma without clinical vertebrobasilar ischemic sequelae.

Transpedicular lag screw placement in traumatic cervical spondylolisthesis: Case report and systematic review of the literature

Traumatic spondylolisthesis of C2-C3 is an unstable fracture. Posterior fixation techniques can be employed with intraoperative navigation, however this tool is not available to all spine surgeons. Furthermore, the evidence for posterior surgical stabilization of C2, while adhering to motion preservation principles is currently unknown. The authors describe a patient who had fractures of the pedicle and vertebral body of C2 and C3, which was successfully stabilized with freehand placement of C2 pedicle lag screws and subsequent C2-C5 fixation. Subsequently, a systematic review was performed to evaluate studies that utilized C2 lag screw placement in patients with traumatic spondylolisthesis of the axis (TSA). Eight retrospective case series were identified (N = 63 patients). Five studies evaluated an open posterior cervical approach and 3 investigated a percutaneous approach. Follow-up time ranged from 2 to 48 months and fusion was successful in most cases. No intra-operative complications were reported. On final follow-up, 2 patients had unintentional C2-C3 fusion, and 3 had C2-C3 instability. Three minor complications (urinary tract infection, surgical site hematoma, respiratory infection) were also reported, that resolved with medical management. Freehand placement of C2 pedicle lag screws may be a viable option in select cases. While posterior C2 lag-screw fixation demonstrated successful fusion in most patients with TSA, the supporting evidence is limited to level IV studies.

An epidemiologic profile of children with special health care needs

OBJECTIVE

To present an epidemiologic profile of children with special health care needs using a new definition of the population developed by the federal Maternal and Child Health Bureau.

METHODS

We operationalized the new definition using the recently released 1994 National Health Interview Survey on Disability. Estimates are based on 30 032 completed interviews for children <18 years old. The overall response rate was 87%.

RESULTS

Eighteen percent of US children <18 years old in 1994, or 12.6 million children nationally, had a chronic physical, developmental, behavioral, or emotional condition and required health and related services of a type or amount beyond that required by children generally. This estimate includes children with existing special health care needs but excludes the at-risk population. Prevalence was higher for older children, boys, African-Americans, and children from low-income and single-parent households. Children with existing special health care needs had three times as many bed days and school absence days as other children. An estimated 11% of children with existing special health care needs were uninsured, 6% were without a usual source of health care, 18% were reported as dissatisfied with one or more aspects of care received at their usual source of care, and 13% had one or more unmet health needs in the past year.

CONCLUSIONS

A substantial minority of US children were identified as having an existing special health care need using national survey data. Children with existing special health care needs are disproportionately poor and socially disadvantaged. Moreover, many of these children face significant barriers to health care.

Using a Standard Staffing Index to allocate nursing staff

The Standard Staffing Index (SSI) was established as a method to determine unit staffing needs and allocate staff effectively. Daily staffing is based on the SSI, the average patient acuity, and the unit census. This has resulted in time savings to determine staffing needs and accurate monitoring of staffing patterns and productivity by nurse managers. The SSI is based on specific patient needs as determined by regular evaluations and audits.

Continuous improvement in health care: transforming the hospital department

Each department in a hospital is given the responsibility of managing its own day-to-day work. For the hospital as a whole to change, the individual departments must undergo a similar change. As each department aligns itself with the purposes of the whole organization, synergy is created and the hospital gradually, incrementally, becomes a new kind of place to give and receive care.

Diagnosis of asbestosis by a time expanded wave form analysis, auscultation and high resolution computed tomography: a comparative study

BACKGROUND

Crackles are a prominent clinical feature of asbestosis and may be an early sign of the condition. Auscultation, however, is subjective and interexaminer disagreement is a problem. Computerised lung sound analysis can visualise, store, and analyse lung sounds and disagreement on the presence of crackles is minimal. High resolution computed tomography (HRCT) is superior to chest radiography in detecting early signs of asbestosis. The aim of this study was to compare clinical auscultation, time expanded wave form analysis (TEW), chest radiography, and HRCT in detecting signs of asbestosis in asbestos workers.

METHODS

Fifty three asbestos workers (51 men and two women) were investigated. Chest radiography and HRCT were assessed by two independent readers for detection of interstitial opacities. HRCT was performed in the supine position with additional sections at the bases in the prone position. Auscultation for persistent fine inspiratory crackles was performed by two independent examiners unacquainted with the diagnosis. TEW analysis was obtained from a 33 second recording of lung sounds over the lung bases. TEW and auscultation were performed in a control group of 13 subjects who had a normal chest radiograph. There were 10 current smokers and three previous smokers. In asbestos workers the extent of pulmonary opacities on the chest radiograph was scored according to the International Labour Office (ILO) scale. Patients were divided into two groups: 21 patients in whom the chest radiograph was > 1/0 (group 1) and 32 patients in whom the chest radiograph was scored < or = 1/0 (group 2) on the ILO scale.

RESULTS

In patients with an ILO score of < or = 1/0 repetitive mid to late inspiratory crackles were detected by auscultation in seven (22%) patients and by TEW in 14 (44%). HRCT detected definite interstitial opacities in 11 (34%) and gravity dependent subpleural lines in two (6%) patients. All but two patients with evidence of interstitial disease or gravity dependent subpleural lines on HRCT had crackles detected by TEW. In patients with an ILO score of > 1/0 auscultation and TEW revealed mid to late inspiratory crackles in all patients, whereas HRCT revealed gravity dependent subpleural lines in one patient and signs of definite interstitial fibrosis in the rest. In normal subjects crackles different from those detected in asbestosis were detected by TEW in three subjects but only in one subject by auscultation. These were early, fine inspiratory crackles.

CONCLUSION

Mid to late inspiratory crackles in asbestos workers are detected by TEW more frequently than by auscultation. Signs of early asbestosis not apparent on the plain radiograph are detected by TEW and HRCT with similar frequency. off

Radiological evidence of progression of bronchiectasis

Radiological evidence of progression of bronchiectasis was sought in a group of 84 consecutive adult patients admitted to a tertiary unit with a particular interest in the disease. Methodical comparison for each patient of the earliest and most recent chest X-rays (n = 84), bronchograms (n = 1) and thoracic computed tomography (CT) scans (n = 32) was performed. Fifteen patients (18%) were considered to show radiological evidence of progression of bronchiectasis, 14 on chest X-ray, two of whom also showed progression on CT scans, and in one patient on bronchography alone. The likelihood of finding evidence of radiological progression increased the longer the interval between examinations. Serial radiology allows identification of patients with progression of disease and indicates the need to review management strategy.

High resolution computed tomographic assessment of asbestosis and cryptogenic fibrosing alveolitis: a comparative study

BACKGROUND

The aim of this study was to compare the distribution and configuration of lung opacities in patients with cryptogenic fibrosing alveolitis and asbestosis by high resolution computed tomography.

METHODS

Eighteen patients with cryptogenic fibrosing alveolitis and 24 with asbestosis were studied. Two independent observers assessed the type and distributions of opacities in the upper, middle, and lower zones of the computed tomogram.

RESULTS

Upper zone fibrosis occurred in 10 of the 18 patients with cryptogenic fibrosing alveolitis and in six of the 24 patients with asbestosis. A specific pattern in which fibrosis was distributed posteriorly in the lower zones, laterally in the middle zones, and anteriorly in the upper zones was seen in 11 patients with cryptogenic fibrosing alveolitis and in four with asbestosis. Band like intrapulmonary opacities, often merging with the pleura, were seen in 19 patients with asbestosis but in only two with cryptogenic fibrosing alveolitis. Areas with a reticular pattern and a confluent or ground glass pattern were the commonest features of cryptogenic fibrosing alveolitis (15 and 14 patients respectively) but were uncommon in asbestosis (four and three patients). Pleural thickening or plaques were seen in 21 patients with asbestosis and in none with cryptogenic fibrosing alveolitis.

CONCLUSION

Apart from showing pleural disease high resolution computed tomography showed that confluent (ground glass) opacities are common in cryptogenic fibrosing alveolitis and rare in asbestosis whereas thick, band like opacities are common in asbestosis and rare in cryptogenic fibrosing alveolitis.

Accuracy of the Denver-II in developmental screening

One of the oldest and best known developmental screening tests was recently restandardized and revised as the Denver-II. Because it was published without evidence of its accuracy, the present study was undertaken with 104 children between 3 and 72 months of age attending one of five day-care centers. To determine the presence of developmental problems, children were administered individual measures of intelligence, speech-language, achievement, and adaptive behavior. A second psychological examiner, blind to the outcome of the diagnostic battery, administered the Denver-II. Developmental problems including language impairments, learning disabilities, mild mental retardation, and/or functional developmental delay were found in 17% of the children. The Denver-II identified correctly 83% and thus had high rates of sensitivity. However, more than half the children with normal development also received abnormal, questionable, or untestable Denver-II scores. Thus the test had limited specificity (43%) and a high overreferral rate. The alternative scoring method, categorizing questionable/untestable scores as normal, caused sensitivity to drop to 56% although specificity rose to 80%. Since neither scoring method produced acceptable levels of accuracy, an effort was made to locate the sources of accuracy and inaccuracy within the test. Only items in the language domain were modestly helpful in discriminating children with and without difficulties. The findings suggest that the authors of the Denver-II need to engage in further development of the instrument including revising scoring criteria and item placement in relation to children's ages. In the interim, test users should employ screening tests which are more accurate such as the Minnesota Inventories or the Battelle Developmental Inventory Screening Test.

High resolution computed tomography in adult cystic fibrosis patients with mild lung disease

Chest radiography and high resolution computed tomography (HRCT) were used to evaluate the degree of lung involvement in 38 adult cystic fibrosis patients with unusually mild pulmonary disease. Abnormal features were present on the chest radiograph and/or high resolution CT scans of 35 patients, while in three patients both investigations were normal. Thickening of the wall of proximal right upper lobe bronchi was the earliest abnormal feature on HRCT. The commonest abnormal feature in these patients, including those whose chest radiograph was normal, was mild, uniform dilatation of proximal bronchi. The lumen dilatation was always less marked than the degree of thickening. Ten of the patients were first diagnosed in adult life. Although HRCT scans were normal in two of these patients, there were features suggestive of early pulmonary disease in the remaining eight.

Detection of bronchiectasis by high-resolution computed tomography in the yellow nail syndrome

High resolution computed tomography of the lungs was performed in three patients with the yellow nail syndrome to detect bronchiectasis. Standard CT was performed in a fourth patient. Evidence of bronchiectasis with bronchial wall thickening and bronchial dilatation was observed in all four patients. High resolution CT is a non-invasive method for detecting and assessing the extent of airway disease in the yellow nail syndrome.

Combined cryptogenic fibrosing alveolitis and emphysema: the value of high resolution computed tomography in assessment

Simple tests of lung function may be misleading in the assessment of patients with interstitial lung disease. Eight patients are described with cryptogenic fibrosing alveolitis (histologically proven in four) with severe breathlessness and low gas transfer (median DLCO 32.4%, range 9.2 to 35.3%, % predicted) in whom lung volumes were preserved [median VC 98.7, range 67.5-131.1%; median TLC 92.5, range 88.1 to 121.2, (% predicted)], and in whom there was no evidence of airflow obstruction [median FEV1/FVC 84.6, range 68-116 (% predicted)]. All were current or ex-heavy smokers. Thoracic high resolution computed tomography revealed upper zone emphysema, the extent of which was not appreciated using conventional chest radiography. The atypical physiological and radiological features can be explained by coincidental cryptogenic fibrosing alveolitis and emphysema and high resolution computed tomography was valuable in the assessment of these patients.

Indium-111 labelled granulocyte scanning to detect inflammation in the lungs of patients with chronic sputum expectoration

Thirty eight patients with chronic sputum expectoration underwent indium-111 labelled granulocyte lung scanning and measurement of whole body loss of indium-111 labelled granulocytes. Twenty four patients had radiologically proved bronchiectasis and 14 had mucus hypersecretion without radiological evidence of bronchiectasis. None was having an acute exacerbation at the time of the scan. The median 24 hour volume of sputum expectorated was 17 (range 2-175) ml. The 24 hour volume of purulent sputum was 5 (0-142) ml; six patients expectorated mucoid sputum only. Twenty one of the 38 patients had a positive granulocyte lung scan. All nine patients expectorating more than 20 ml purulent sputum in 24 hours had positive lung scans and all had lost more than 19% of the indium-111 from the body after five to seven days. Of the six patients with mucoid sputum, only one had a positive scan and these subjects lost only 6-11% of the indium-111 in five to seven days. The percentage loss of indium-111 from the body correlated with 24 hour purulent sputum volume (r = 0.41, n = 38, p less than 0.001) and total elastolytic activity in 24 hour sputum (r = 0.54, n = 14, p less than 0.01). The loss of indium-111 was not related to the extent of bronchiectasis when purulent sputum volume was allowed for. Indium-111 labelled granulocyte scanning provides a sensitive and objective method for detecting inflammation in the lungs and should help to improve understanding of chronic bronchial sepsis and possibly treatment in selected cases.

Comparison of thin section computed tomography with bronchography for identifying bronchiectatic segments in patients with chronic sputum production

Computed tomography is widely used in the investigation of patients in whom bronchiectasis is suspected, despite considerable variation in its reported sensitivity and specificity. The findings with 3 mm high resolution computed tomography were compared at segmental level with bronchography by two radiologists independently in 27 patients (aged 20-67 years) undergoing investigation of chronic sputum production. Fifteen patients were found to have bronchiectasis by both investigations. Five were identified by computed tomography alone, including two in whom disease was revealed in segments underfilled at bronchography. The sensitivity of computed tomography compared with bronchography in the diagnosis of bronchiectasis at segmental level was 84% and the specificity 82%. The predictive value of computed tomography in the diagnosis of bronchiectasis was 38% overall, but increased to 75% when only those segmental bronchi moderately or severely dilated on the computed tomography scan were considered. There was no relation between the degree of bronchial wall thickening on the computed tomogram and the diagnosis of bronchiectasis by bronchography. Bronchography may be avoided in patients being considered for surgical resection of their bronchiectasis in whom computed tomography shows diffuse disease.

Computed tomography in adult obliterative bronchiolitis

Fifteen adults with obliterative bronchiolitis (OB) were investigated with computed tomography (CT). CT was considered to be abnormal in 13/15 patients (87%) showing widespread areas of increased attenuation of a patchy nature and variable proportion. CT revealed more extensive changes than the chest radiograph or bronchogram. It is a non-invasive well-tolerated and easily repeatable technique and may have an important role in the radiological evaluation of adults with OB.

Pulmonary involvement in systemic sclerosis: the detection of early changes by thin section CT scan, bronchoalveolar lavage and 99mTc-DTPA clearance

Systemic sclerosis is frequently complicated by fibrosing alveolitis although clinical and radiological abnormalities are not usually apparent until the lung disease is well established. The aim of this study was to investigate pulmonary involvement in systemic sclerosis by thin section CT scan, bronchoalveolar lavage (BAL) and 99mTc-DTPA clearance studies, and assess the value of these tests in defining pulmonary abnormalities in patients with a normal chest radiograph. Patients were divided into those with an abnormal chest radiograph (Group I, n = 14) and those with a normal chest radiograph (Group II, n = 16). CT scans were abnormal in all patients in Group I and 7 of 16 (44%) in Group II. BAL inflammatory cell counts were raised in all 12 (100%) patients studied in Group I and 11 of 15 (73%) in Group II. There was no difference in the type of inflammatory cells observed between the two groups. 99mTc-DTPA clearance was faster than normal controls in ten of 14 patients (71%) in Group I and seven of 15 (47%) in Group II and correlated with carbon monoxide transfer factor (P less than 0.05). Lung biopsies were performed on nine patients in Group I and three in Group II all of whom had abnormal CT scans. Fibrosing alveolitis was confirmed in every case. Group II biopsies could not be distinguished from Group I biopsies; both showed fibrosis as well as inflammation suggesting that pulmonary fibrosis is an early abnormality in systemic sclerosis. Our results indicate that CT scans, BAL and 99mTc-DTPA are frequently abnormal in asymptomatic patients with systemic sclerosis who have normal chest radiographs. When the CT scan is normal abnormalities of BAL and/or 99mTc-DTPA (99mTechnetium diethylenetriamine pentacetate) clearance may indicate lung disease at a still earlier stage. This observation requires further investigation.

Diaphragm strength in the shrinking lung syndrome of systemic lupus erythematosus

The cause of the reduced lung volume in the 'shrinking lung' syndrome of systemic lupus erythematosus (SLE) was investigated in 12 patients with the condition. Nine patients described persistent episodes of pleuritic chest pain. Narrow section (3 mm) computed tomography of the thorax revealed no interstitial fibrosis or significant pleural disease. Assessment of diaphragmatic function using manoeuvres more reliable than the maximal occluded efforts previously used alone to assess respiratory muscle strength, showed that diaphragm strength was unequivocally normal in nine of 12 patients. In three, maximum transdiaphragmatic pressure was moderately reduced, but phrenic nerve stimulation demonstrated that this was due to incomplete activation of the diaphragm during a maximal voluntary effort, rather than to a primary abnormality of the diaphragm. Results of maximum lung recoil pressures and dynamic compliance, and analysis of the 12-s maximum voluntary ventilation, suggested a restriction in chest-wall expansion, although it was not possible to identify the underlying cause of this on the basis of our results. We conclude that the 'shrinking lung' syndrome of SLE is not explained by a primary abnormality of the diaphragm.

Computed tomography of diffuse lung disease

The place of computed tomography (CT) scanning in the detection of pulmonary nodules is now well established. Due to the increasing spatial resolution of CT and shorter scan times, patients with diffuse lung disease can now be examined more effectively. Narrow section CT demonstrates the morphological detail of some diffuse lung diseases at an earlier stage than conventional radiography.

High-resolution computed tomography in pulmonary cystic fibrosis

Twenty-one patients with established cystic fibrosis were examined using high-resolution, narrow-section computed tomography. The bronchiectasis of cystic fibrosis is described and is shown to be characteristic in many respects. Computed tomography was found to be more accurate than standard radiography in locating the disease process and demonstrated pleural involvement which was not apparent on chest radiographs.

The value of high definition, narrow section computed tomography in fibrosing alveolitis

Fibrosing alveolitis was studied by high definition, narrow section computed tomography (CT) in 50 patients, 30 of whom were suffering from systemic sclerosis and 20 from cryptogenic fibrosing alveolitis (CFA). Apart from changes in the mid and lower zones, abnormalities were also observed anteriorly in the upper lobes and in the pleura. Scanning in the prone position was important in seeking evidence of minimal pathological change. In systemic sclerosis CT was 24% more accurate than high kilovoltage radiography in demonstrating minimal evidence of fibrosing alveolitis; this had a characteristic distribution as a peripheral crescent of high attenuation in the lower lobes before any changes were visible on standard radiographs. The CT appearances in CFA were also characteristic, particularly when the disease appeared to be early or limited. We believe that high definition CT may be of value in suggesting the diagnosis of CFA in patients with non-specific abnormalities on the chest radiograph.

Comparison of narrow section computed tomography and plain chest radiography in chronic allergic bronchopulmonary aspergillosis

Narrow section (3 mm width slices every 10 mm) computed tomography on an Elscint 2002 scanner and plain chest radiography were performed in 10 patients with allergic bronchopulmonary aspergillosis. No patient was experiencing an acute exacerbation. The investigations were reported separately and in random order. Bronchiectasis was reported in 31 of 60 lobes on computed tomography compared with only 15 on plain chest radiographs. Computed tomography was also more sensitive for proximal bronchiectasis detected in 16 lobes compared with only in 10 on plain chest radiographs. Serial computed tomography may allow earlier identification of progression of lung damage in patients with allergic bronchopulmonary aspergillosis and so help in planning treatment.

Intrathoracic aspergilloma: role of CT in diagnosis and treatment

The authors describe the computed tomographic (CT) appearances of aspergilloma in 26 patients. With narrow (3-mm) sections, a bone algorithm, and wide window settings, CT scans enabled accurate identification of both the forming aspergilloma as well as the mature fungus ball in 25 cases. The diagnostic accuracy of CT was confirmed histologically in nine cases. The radiologic concept of the aspergilloma as a solid mass partially surrounded by a crescent of air is no longer tenable as the only definite criterion for diagnosis. In cases in which this classic appearance is seen on CT scans, mobility is easily demonstrated with use of prone and supine positions. In other cases, the aspergilloma appears as an irregular spongework containing air spaces and filling the cavity, obliterating the air crescent sign. The fungus ball is therefore fixed and immobile. Forming aspergillomas can also be identified by the fungal strands that fall into the cavity lumen, trapping air and initiating the sponge-work appearance. The CT appearance in patients with positive precipitins is characteristic and allows earlier diagnosis than does conventional tomography.

Role of computed tomography in diagnosis of bronchiectasis

Bronchograms and computed tomograms were performed in 27 patients who presented consecutively for bronchography with chronic sputum production. The films were reported separately by three consultant radiologists, who had been asked to give a diagnostic interpretation of the films for each bronchopulmonary segment. The reporting of bronchiectasis on computed tomograms was compared with that on bronchograms. The sensitivity and specificity of computed tomography at segmental level compared with bronchography was 66% and 92%, respectively. We conclude that computed tomography alone is not yet suitable for accurate characterisation and localisation of disease in patients in whom surgery is contemplated. Computed tomography may be useful in patients in whom bronchography is contraindicated and for monitoring progression of disease after initial combined computed tomography and bronchography.