Autobiographical memory in chronic schizophrenia: A follow-up study

Chronic schizophrenia is a very disabling disease and patient's social integration remains difficult. One important aspect is autobiographical memory (AM) as it is impaired in schizophrenia and highly correlated to patient's outcome, since its closely linked to self and identity. Reduced specificity and lack of details are characteristics of patients' AM, but its longitudinal course in schizophrenia remains unclear. We examined 21 patients who underwent our protocol twice with an interval of 7 years. AM was assessed using a semi-structured interview, covering four periods of life and addressing semantic knowledge and autobiographical episodes as well as their details. The results can be divided into three parts, separating semantic memories, specific autobiographical memories and details describing the latter. While a significant deterioration of semantic AM over time could be revealed, the specificity of the free recalled autobiographical episodes remained rather stable - albeit on a low level. In contrast, unique events were remembered with significantly less details at follow-up than at the first examination. While floor-effects given a relatively small number of unique events have to be considered, semantic AM and episodic details seem to be a valuable target for AM remediation given their further deterioration over time.

Structural brain networks in schizophrenia based on nonnegative matrix factorization

Schizophrenia is a severe mental disease with significant morphometric reductions in gray matter volume and cortical thickness in a variety of brain regions. However, most studies only focused on the voxel level alterations in specific cerebral regions and ignored the spatial relationship between voxels. In the present study, we used a novel, data-driven technique-nonnegative matrix factorization (NMF) to group voxels with similar information into a network, and studied the structural covariance at the network level in schizophrenia. Our sample included 36 patients with schizophrenia and 21 healthy controls. Compared with healthy controls, patients with schizophrenia showed significant gray matter volume reductions in six structural covariance networks (dorsal striatum, thalamus, hippocampus-parahippocampus, supplementary motor area-fusiform, middle/inferior temporal network, frontal-parietal-occipital network). Our findings confirmed the assumption of a disturbance in the cortical-subcortical circuit in schizophrenia and suggested that NMF is a useful multivariate method to identify brain networks, which provides a new perspective to study the neural mechanism in schizophrenia.

Autobiographical memory impairment in chronic schizophrenia: Significance and clinical correlates

Previous studies of autobiographical memory (AM) in schizophrenia yielded a reduction of specificity, richness of details and conscious recollection, which indicate both, quantitative and qualitative AM changes. However, their associations with psychopathological symptoms and neuropsychological deficits were not resolved. Therefore, we sought to investigate AM with respect to psychopathology and neuropsychology in patients with chronic schizophrenia to rule out the influence of different courses of the disease. AM of four lifetime periods was examined in 75 patients and 50 healthy controls by using a semi-structured interview. The recalled episodes were rated for memory specificity. Subsequently, one single event of each period of life was rated for details and experiential aspects of reliving (originality, vividness/visual imagery, emotional re-experiencing and emotional valence). When contrasted with healthy controls, patients recalled a significantly reduced number of episodes and personal semantic facts; moreover, memory specificity of AM was significantly lower in patients than controls. While the richness of details calculated for single events showed only minor, non-significant group differences, vividness and emotional re-experiencing were significantly less pronounced in the patient group. Along with this, AM performance correlated significantly with negative symptoms including apathy as well as verbal memory and executive functions. Our results underline the significance of overgenerality as a key feature of AM in schizophrenia as well as a dissociation between intact number of details of single events and reduced vividness and emotional re-experiencing. The extent of negative symptoms including apathy and impairments of verbal memory/executive functions may explain AM deficits in chronic schizophrenia.

Neurological soft signs and structural network changes: a longitudinal analysis in first-episode schizophrenia

BACKGROUND

Neurological soft signs (NSS) are often reported in patients with schizophrenia and may vary with psychopathological symptoms during the course of disease. Many cross-sectional neuroimaging studies have shown that NSS are associated with disturbed network connectivity in schizophrenia. However, it remains unclear how these associations change over time during the course of disorder.

METHODS

In present study, 20 patients with first-episode schizophrenia and 20 controls underwent baseline structural magnetic resonance imaging (MRI) scan and at one-year follow-up. Structural network characteristics of patients and controls were analyzed using graph theoretical approach based on MRI data. NSS were assessed using the Heidelberg scale.

RESULTS

At baseline, patients demonstrated significant changes of the local network properties mainly involving regions of the cortical-subcortical-cerebellar circuits compared to healthy controls. For further analysis, the whole patient group was dichotomized into a NSS-persisting and NSS-decreasing subgroup. After one-year follow-up, the NSS-persisting subgroup showed decreased betweenness in right inferior opercular frontal cortex, left superior medial frontal cortex, left superior temporal cortex, right putamen and cerebellum vermis and increased betweenness in right lingual cortex. However, the NSS-decreasing subgroup exhibited only localized changes in right middle temporal cortex, right insula and right fusiform with decreased betweenness, and in left lingual cortex with increased betweenness.

CONCLUSIONS

These findings provide evidence for brain network reorganization subsequent to clinical disease manifestation in patients with first-episode schizophrenia, and support the hypothesis that persisting NSS refer to progressive brain network abnormalities in patients with schizophrenia. Therefore, NSS could help to establish a better prognosis in first-episode schizophrenia patients.

Neurological soft signs and brain morphology in people living with HIV

Neurological soft signs (NSS) are a common feature of severe psychiatric disorders such as schizophrenia but are also prevalent in organic brain diseases like HIV-associated neurocognitive disorder (HAND) or Alzheimer’s disease. While distinct associations between NSS, neurocognition, and cerebral regions were demonstrated in schizophrenia, these associations still have to be elucidated in HIV. Therefore, we investigated 36 persons with HIV of whom 16 were neurocognitively healthy and 20 were diagnosed with HAND. NSS were assessed using the Heidelberg scale. NSS scores were correlated with gray matter (GM) using whole brain voxel-based morphometry. Results showed significantly elevated NSS in the HAND group when compared to the neurocognitively healthy with respect to NSS total score and the subscores “orientation” and “complex motor tasks”. While the two groups showed only minor, non-significant GM differences, higher NSS scores (subscales “motor coordination”, “orientation”) were significantly correlated with GM reduction in the right insula and cerebellum (FWE-corrected). Our results corroborate elevated NSS in HIV+ patients with HAND in contrast to cognitively unimpaired patients. In addition, cerebral correlates of NSS with GM reductions in insula and cerebellum were revealed. Taken together, NSS in this patient group could be considered a marker of cerebral damage and neurocognitive deficits.

Neural Correlates of Autobiographical Memory: Evidence From a Positron Emission Tomography Study in Patients With Mild Cognitive Impairment and Alzheimer's Disease

Background: Autobiographical memory (AM) changes are the hallmark of Alzheimer's disease (AD) and mild cognitive impairment (MCI). In recent neuroimaging studies, AM changes have been associated with numerous cerebral sites, such as the frontal cortices, the mesial temporal lobe, or the posterior cingulum. Regional glucose uptake in these sites was investigated for underlying subdimensions using factor analysis. Subsequently, the factors were examined with respect to AM performance in a subgroup of patients. Methods: Data from 109 memory clinic referrals, who presented with MCI (n = 60), mild AD (n = 49), or were cognitively intact, were analyzed. The glucose metabolic rates determined by positron emission tomography (PET) with 18F-fluorodeoxyglucose (FDG) in 34 cerebral sites important for AM were investigated for underlying subdimensions by calculating factor analysis with varimax rotation. Subsequently, the respective factor scores were correlated with the episodic and semantic AM performance of 22 patients, which was measured with a semi-structured interview assessing episodic memories (characterized by event-related emotional, sensory, contextual, and spatial-temporal details) and personal semantic knowledge from three periods of life (primary school, early adulthood, and recent years). Results: Factor analysis identified seven factors explaining 69% of the variance. While patients with MCI and AD showed lower values than controls on the factors frontal cortex, mesial temporal substructures, and occipital cortex, patients with MCI presented with increased values on the factors posterior cingulum and left temporo-prefrontal areas. The factors anterior cingulum and right temporal cortex showed only minor, non-significant group differences. Solely, the factor mesial temporal substructures was significantly correlated with both episodic memories (r = 0.424, p < 0.05) and personal semantic knowledge (r = 0.547, p < 0.01) in patients with MCI/AD. Conclusions: The factor structure identified corresponds by large to the morphological and functional interrelations of the respective sites. While reduced glucose uptake on the factors frontal cortex, mesial temporal substructures, and occipital cortex in the patient group may correspond to neurodegenerative changes, increased values on the factors posterior cingulum and left temporo-prefrontal areas in MCI may result from compensatory efforts. Interestingly, changes of the mesial temporal substructures were correlated with both semantic and episodic AM. Our findings suggest that AM deficits do not only reflect neurodegenerative changes but also refer to compensatory mechanisms as they involve both quantitative losses of specific memories and qualitative changes with a semantization of memories.

Neurological soft signs (NSS) and gray matter volume (GMV) in first-episode psychosis: An analysis of NSS motor subscores

We aimed to study the correlations between gray matter volume and the motor subscores of NSS in first-episode psychosis patients with both, whole brain and region of interest analyses. The structural MRIs of 81 first-episode psychosis patients were analyzed by using voxel-based morphometry (VBM) for SPM. NSS were assessed using the Heidelberg scale. Significant decreases of gray matter volume were correlated to high NSS total scores and, more specifically, frontal, subcortical and cerebellar areas were significantly correlated with increased scores of the subscores Motor Coordination (MoCo) and Complex Motor Tasks (CMT). When applying a stricter statistical correction, only the frontal gyrus and caudate nucleus survived for MoCo; whereas the precentral and superior frontal gyri survived for CMT. When doing regional analyses, using as masks the structures deemed as significant by the whole brain analyses and applying the FWE-correction, the superior frontal gyrus, thalamus and caudate nucleus correlated negatively with MoCo; and the precentral and superior frontal gyri, thalamus and caudate nucleus showed inverse correlations with CMT. These results suggest that cerebral cortex, subcortical structures (thalamus and striatum) and cerebellum are inversely correlated to both motor NSS subscores, the first time a study describes this relationship for all the relevant structures simultaneously. For its part, ROI proves to be effective demonstrating that subcortical structures (thalamus and caudate) are the most affected by motor NSS.

Neurological soft signs (NSS) and brain morphology in patients with chronic schizophrenia and healthy controls

Subtle abnormalities in sensory integration, motor coordination and sequencing of complex motor acts or neurological soft signs (NSS) are characteristic phenomena in patients with schizophrenia at any stage of the illness. Previous MRI studies in schizophrenia found NSS to be associated with cortical, thalamic and cerebellar changes. Since these studies mainly focused on first-episode or recent onset schizophrenia, the cerebral correlates of NSS in chronic schizophrenia remained rather unclear. 49 middle-aged patients with chronic schizophrenia with a mean duration of illness of 20.3 ± 14.0 years and 29 healthy subjects matched for age and sex were included. NSS were examined on the Heidelberg Scale and correlated to grey matter (GM) by using whole brain high resolution magnetic resonance imaging (3 Tesla) with SPM12/CAT12 analyses. As expected, NSS in patients were significantly (p≤0.001) elevated in contrast to healthy controls, a finding, which not only applied to NSS total score, but also to the respective subscales "motor coordination", "sensory integration", "complex motor tasks", "right/left and spatial orientation" and "hard signs". Within the patient group NSS total scores were significantly correlated to reduced GM in right lingual gyrus, left parahippocampal gyrus, left superior temporal gyrus, left thalamus (medial dorsal nucleus) and left posterior lobe of the cerebellum (declive). Respective negative associations could also be revealed for the subscales "motor coordination", "complex motor tasks" and "right/left and spatial orientation". These findings remained significant after FWE-correction for multiple comparisons and were confirmed when years of education, chlorpromazine-equivalents or variables indicating the severity of psychopathology were introduced as additional covariates. According to our results lingual, parahippocampal, superior temporal, inferior and middle frontal gyri, thalamus and cerebellum have to be considered as important sites of NSS in chronic schizophrenia. That these findings only applied for patients but not healthy controls may indicate a different pathogenesis of NSS.

Neurological Soft Signs and Brain Network Abnormalities in Schizophrenia

Neurological soft signs (NSS) are often found in patients with schizophrenia. A wealth of neuroimaging studies have reported that NSS are related to disturbed cortical-subcortical-cerebellar circuitry in schizophrenia. However, the association between NSS and brain network abnormalities in patients with schizophrenia remains unclear. In this study, the graph theoretical approach was used to analyze brain network characteristics based on structural magnetic resonance imaging (MRI) data. NSS were assessed using the Heidelberg scale. We found that there was no significant difference in global network properties between individuals with high and low levels of NSS. Regional network analysis showed that NSS were associated with betweenness centrality involving the inferior orbital frontal cortex, the middle temporal cortex, the hippocampus, the supramarginal cortex, the amygdala, and the cerebellum. Global network analysis also demonstrated that NSS were associated with the distribution of network hubs involving the superior medial frontal cortex, the superior and middle temporal cortices, the postcentral cortex, the amygdala, and the cerebellum. Our findings suggest that NSS are associated with alterations in topological attributes of brain networks corresponding to the cortical-subcortical-cerebellum circuit in patients with schizophrenia, which may provide a new perspective for elucidating the neural basis of NSS in schizophrenia.

Associations between brain structural networks and neurological soft signs in healthy adults

Neurological soft signs (NSS), as minor neurological deficits, have been identified in several psychiatric disorders, especially in schizophrenia. However, it's unclear how the neuropathological processes of the disease affect NSS related brain morphological changes and whether it is confounded by the use of medication. As NSS also exist in healthy people, the potential confounding effects of psychopathology or medication will be excluded if NSS are investigated in healthy people. Therefore, we applied a novel multivariate approach, source-based morphometry (SBM), to study structural networks in relation to NSS in healthy adults based on structural magnetic resonance imaging (MRI) data. The Heidelberg Scale was applied to evaluate NSS. Using SBM, we constructed structural networks and investigated their associations with NSS in healthy adults. Six grey matter (GM) structural networks were identified. Sensory integration subscores were associated with the cerebellar component and the cortico-basal ganglia-thalamic component. Motor coordination subscores and total NSS scores were associated with the sensorimotor component. The present findings indicated that structural network abnormalities in cerebellar, subcortical and cortical sensorimotor areas contribute to NSS performance in healthy adults.

Neurological soft signs (NSS) and cognitive impairment in chronic schizophrenia

Recent studies indicate that neurological soft signs (NSS) in schizophrenia are associated with generalized cognitive impairments rather than changes in specific neuropsychological domains. However, the majority of studies solely included first-episode patients or patients with a remitting course and did not consider age, course, education or severity of global cognitive deficits as potential confounding variables. Therefore, we examined NSS with respect to cognitive deficits in chronic schizophrenia, i.e. patients who are particularly vulnerable to both, NSS and cognitive impairments.

Eighty patients with chronic schizophrenia (43.36 ± 15a) and 60 healthy controls (47.52 ± 14.8a) matched for age, sex and years of education were examined on the Heidelberg NSS scale and a broad neuropsychological battery including short term, working, logical and autobiographic memory (AM), theory of mind (ToM), psychomotor speed and cognitive flexibility.

When contrasted with the controls, patients showed significantly higher NSS scores and impairments in all neuropsychological domains but short-term memory. NSS were significantly associated with all neuropsychological domains considered but short-term memory and semantic AM. Except for episodic AM (which was significantly correlated with NSS in patients only) these correlations applied to both groups and were confirmed when age, years of education and severity of global cognitive deficits (Mini Mental State Examination) were controlled for.

Results demonstrate that NSS reflect a rather wide range of cognitive impairments in schizophrenia, which also involves episodic AM and ToM. These associations were not accounted for by age, education or severity of global cognitive deficits and facilitate the clinical usage of NSS as a screening instrument.

Neurological soft signs and grey matter abnormalities in individuals with ultra-high risk for psychosis

Neurological soft signs (NSSs), conventionally defined as subtle neurological abnormalities, are frequently found in individuals with schizophrenia. Many neuroimaging studies have also reported that NSSs are associated with grey matter changes in patients with schizophrenia at different stages of the illness. However, these findings may be confounded by the effect of antipsychotic medications, chronicity, and duration of untreated psychosis. Examining NSSs in individuals with ultra-high risk (UHR) for psychosis may help to identify the neuroanatomical substrates of NSSs related to the illness itself and to avoid these potential confounding effects. A sample of 21 individuals with UHR were included in the present study. NSSs were rated using the abridged version of the Cambridge Neurological Inventory. Grey matter volume was assessed using optimized voxel-based morphometry on images acquired by a high-resolution 3-T magnetic resonance imaging scanner. We found that higher NSS scores in individuals with UHR were associated with decreased grey matter volume at the superior and medial frontal cortex, the rectal cortex, the pre- and post-central cortex, the insula, the caudate, and the cerebellum. Our results suggest that these brain structural characteristics may represent the neuroanatomical substrate of NSSs in individuals with UHR. These findings contribute to the understanding of the intrinsic features of psychosis associated with NSSs and may provide insights into pre-schizophrenia pathophysiology.

Neurological Soft Signs and Psychopathology in Chronic Schizophrenia: A Cross-Sectional Study in Three Age Groups

As established in a wealth of studies subtle motor and sensory neurological abnormalities or neurological soft signs (NSS) are frequently found in patients with schizophrenia at any stage of their illness. However, the potential impact of chronicity and age on NSS was scarcely investigated. Therefore, we assessed NSS in 90 patients with subchronic (n = 22) or chronic (n = 68) schizophrenia and in 60 healthy controls who were assigned to three age groups (18-29, 30-49, and +50 years). NSS were measured on the Heidelberg Scale, psychopathological symptoms including apathy were rated on established instruments. As demonstrated by analysis of variance, NSS scores in patients were significantly (p < 0.05) increased relative to healthy controls. Significant age effects arose in all NSS subscores, with older subjects scoring well above the younger ones. These age effects were more pronounced in patients than controls, indicating that NSS in chronic schizophrenia exceed age-associated changes. Moreover, the NSS scores in patients were significantly associated with duration of illness, thought disturbance, positive symptoms, and apathy. These results were confirmed after age/duration of illness and years of education were partialed out and via regression analyses. Our findings conform to the hypothesis that NSS are associated with chronicity of the disorder as indicated by the correlations of NSS with both, duration of illness and apathy. The correlations between NSS and positive symptoms/thought disturbance correspond to the fluctuation of positive symptoms during the course of the disorder. The significantly more pronounced age effects on NSS in patients may either point to ongoing cerebral changes or to a greater susceptibility of patients toward physiological age effects, which may be mediated among other factors by a lower cognitive reserve.

[Community-acquired pneumonia]

CLINICAL ISSUE

The diagnosis of community-acquired pneumonia (CAP) is often not possible based only on the clinical symptoms and biochemical parameters.

STANDARD RADIOLOGICAL METHODS

For every patient with the suspicion of CAP, a chest radiograph in two planes should be carried out. Additionally, a risk stratification for the decision between outpatient therapy or hospitalization is recommended.

METHODICAL INNOVATIONS

Based on the evaluation of the different radiological patterns as well as their extent and distribution, a rough allocation to so-called pathogen groups as well as a differentiation between viral and bacterial infections are possible; however, because different pathogens cause different patterns an accurate correlation is not feasible by relying purely on imaging.

ACHIEVEMENTS/PRACTICAL RECOMMENDATIONS

The radiological findings serve as proof or exclusion of pneumonia and can also be used to evaluate the extent of the disease (e.g. monolobular, multilobular, unilateral or bilateral). In cases of prolonged disease, suspicion of complications (e.g. pleural effusion or empyema, necrotizing pneumonia or abscess) or comorbid conditions (e.g. underlying pulmonary or mediastinal diseases) computed tomography is an important diagnostic tool in addition to chest radiography. Ultrasound is often used to diagnose pleural processes (e.g. parapneumonic effusion or pleural empyema).

Association of cortical thickness and neurological soft signs in patients with chronic schizophrenia and healthy controls

BACKGROUND

Neurological soft signs (NSS), i.e. subtle neurological abnormalities, have been frequently found in schizophrenia. Neuroimaging studies in schizophrenia have shown abnormal cortical thickness changes across the cortical mantle. However, few studies have examined relationships between NSS and cortical thickness abnormalities in schizophrenia.

METHOD

A sample of 18 patients with chronic schizophrenia and 20 age-matched healthy controls were included. Cortical thickness was assessed on high-resolution 3-tesla magnetic resonance imaging by using FreeSurfer software and NSS were rated on the Heidelberg Scale.

RESULTS

Significant negative correlations between NSS and cortical thickness were found in the prefrontal, inferior temporal, superior parietal, postcentral, and supramarginal cortices in the schizophrenia patients. In the controls, however, this negative correlation was found in the anterior cingulate, pericalcarine and superior/middle temporal regions.

CONCLUSION

Our results not only confirmed the association between NSS and cortical thickness in chronic schizophrenia but also indicated that patients and controls have different anatomical substrates of NSS.

Comparison of grey matter volume and thickness for analysing cortical changes in chronic schizophrenia: a matter of surface area, grey/white matter intensity contrast, and curvature

Grey matter volume and cortical thickness are the two most widely used measures for detecting grey matter morphometric changes in various diseases such as schizophrenia. However, these two measures only share partial overlapping regions in identifying morphometric changes. Few studies have investigated the contributions of the potential factors to the differences of grey matter volume and cortical thickness. To investigate this question, 3T magnetic resonance images from 22 patients with schizophrenia and 20 well-matched healthy controls were chosen for analyses. Grey matter volume and cortical thickness were measured by VBM and Freesurfer. Grey matter volume results were then rendered onto the surface template of Freesurfer to compare the differences from cortical thickness in anatomical locations. Discrepancy regions of the grey matter volume and thickness where grey matter volume significantly decreased but without corresponding evidence of cortical thinning involved the rostral middle frontal, precentral, lateral occipital and superior frontal gyri. Subsequent region-of-interest analysis demonstrated that changes in surface area, grey/white matter intensity contrast and curvature accounted for the discrepancies. Our results suggest that the differences between grey matter volume and thickness could be jointly driven by surface area, grey/white matter intensity contrast and curvature.

Autobiographical memory: a clinical perspective

Autobiographical memory (ABM) comprises memories of one’s own past that are characterized by a sense of subjective time and autonoetic awareness. Although ABM deficits are among the primary symptoms of patients with major psychiatric conditions such as mild cognitive impairment (MCI) and Alzheimer Disease (AD) or chronic schizophrenia large clinical studies are scarce. We therefore summarize and discuss the results of our clinical studies on ABM deficits in the respective conditions. In these studies ABM was assessed by using the same instrument – i.e., the Erweitertes Autobiographisches Gedächtnis Inventar (E-AGI) – thus allowing a direct comparison between diagnostic groups. Episodic ABM, especially the richness of details was impaired already in MCI and in beginning AD. Semantic memories were spared until moderate stages, indicating a dissociation between both memory systems. A recency effect was detectable in cognitively unimpaired subjects and vanished in patients with AD. A similar pattern of deficits was found in patients with chronic schizophrenia but not in patients with major depression. These ABM deficits were not accounted for by gender, or education level and did not apply for the physiological ageing process in otherwise healthy elderly. In conclusion, ABM deficits are frequently found in AD and chronic schizophrenia and primarily involve episodic rather than semantic memories. This dissociation corresponds to the multiple trace theory which hypothesized that these memory functions refer to distinct neuronal systems. The semi-structured interview E-AGI used to discern ABM changes provided a sufficient reliability measures, moreover potential effects of a number of important confounders could be falsified so far. These findings underline the relevance of ABM-assessments in clinical practice.

[HRCT and bronchial asthma: visualization of the pathophysiologic changes of the pulmonary parenchyma after inhalation provocation]

PURPOSE

To characterize parenchymal lung affections morphologically in patients with asthma and healthy subjects by high -resolution computed tomography (HRCT) subsequent to histamine-triggered inhalation bronchoprovocation and salbutamol-induced broncholysis, and to compare the results with pulmonary function tests.

MATERIALS AND METHODS

Fifteen asthmatics with bronchial hyperreactivity, with a > 20% decrease in FEV1 and a > 10 mmHg decrease in PaO(2) after bronchoprovocation (PC20%+), twelve asthmatics with a < 20% decrease in FEV1 and a > 10 mmHg decrease in PaO(2) after bronchoprovocation (PC20%-), and eight healthy persons without bronchial hyperreactivity underwent inhalation bronchoprovocation and broncholysis. Spirometer-triggered HRCT at high lung volumes was performed, and total and peripheral lung densities and the amount of solid lung structures, representing predominantly vessels, were measured.

RESULTS

After bronchoprovocation, we observed significant decreases in total and peripheral lung densities in all groups (p < 0.0005), and a significant increase in lung densities subsequent to bronchodilation (p < 0.0002). The morphological alterations in solid lung structure were not significantly different after bronchoprovocation or broncholysis (p > 0.05), as compared to the baseline measurements. In hyperreactive patients, PaO(2) significantly decreased after provocation and significantly increased after lysis (p < 0.05). In PC20%+ asthmatics, a mean reduction of 27.8% in FEV1 was observed, which was < 20% in the other groups. No significant correlations were observed between radiological data and the results of pulmonary function tests. In healthy persons, we demonstrated highly significant parenchymal response to bronchoprovocation and broncholysis, which was not otherwise documented by pulmonary function tests.

CONCLUSION

In both PC20%+ and PC20%- patients as well as in healthy individuals, HRCT was efficient in the evaluation of pathoanatomical alterations of the lung parenchyma subsequent to inhalation provocation. In healthy individuals, these parenchymal alterations were not documented by pulmonary function tests.

Value of negative spiral CT angiography in patients with suspected acute PE: analysis of PE occurrence and outcome

The aim of this study was to analyze pulmonary embolism (PE) occurrence and retrospective clinical outcome in patients with clinically suspected acute PE and a negative spiral CT angiography (SCTA) of the pulmonary arteries. Within a 35-month period, 485 consecutive patients with clinical symptoms of acute PE underwent SCTA of the pulmonary arteries. Patients with a negative SCTA and without anticoagulation treatment were followed-up and formed the study group. Patient outcome and recurrence of PE was evaluated retrospectively during a period of 6 months after the initial SCTA, and included a review of computerized patient records, and interviews with physicians and patients. Patients were asked to fill out a questionnaire concerning all relevant questions about their medical history and clinical course during the follow-up period. Special attention was focused on symptoms indicating recurrent PE, as well as later confirmation and therapy of PE. Of the 485 patients, 325 patients (67%) had a negative scan, 134 (27.6%) had radiological signs of PE, and 26 (5.4%) had an indeterminant result. Of 325 patients with a negative scan, 269 (83%) were available for follow-up. The main reasons for loss to follow-up were change of address, name, or phone number, or non-resident patients who left abroad. Of 269 patients available for follow-up, 49 patients (18.2% of 269) received anticoagulant treatment because of prior or recent deep venous thrombosis (32.6%) or a history of PE (34.7%), cardiovascular disease (18.4%), high clinical probability (8.2%), positive ventilation-perfusion scan (4.2%), and elevated D-dimer test (2%). The remaining 220 patients, who did not receive anticoagulant medication, formed the study group. Of this study group, 1 patient died from myocardial infarction 6 weeks after the initial SCTA, and the postmortem examination also detected multiple peripheral emboli in both lungs ( p=0.45%; 0.01-2.5, 95% confidence interval). The PE did not occur in any other patient. In patients with suspected PE and negative SCTA without anticoagulant therapy, the risk of recurrent PE in this study was less than 1% and similar to that in patients after a negative pulmonary angiogram. Therefore, we conclude that patients can be managed safely without anticoagulation therapy; however, this approach may not be appropriate for critically ill patients and those with persistent high clinical suspicion of acute PE.

Equipment availability and diagnostic strategies for suspected pulmonary embolism in Austria

The aim of this study was to investigate equipment availability and current diagnostic strategies for suspected pulmonary embolism (PE) in Austrian hospitals. A questionnaire was sent to the medical directors of all Austrian hospitals with emergency and/or surgical, orthopedic, and medical departments. The questionnaire contained questions regarding the available equipment suitable for the imaging diagnosis of PE, the first-line and second-line imaging tests for patients with suspected PE, and additional lower extremity venous imaging and laboratory tests that complement the diagnostic armamentarium. The return rate for questionnaires was 81% (127 of 157 hospitals). There were 97% of hospitals that had the equipment to perform sonography, 59% could perform pulmonary angiography, 54% spiral CT, 19% ventilation/perfusion (V/P) scintigraphy, and 4% perfusion scintigraphy alone. Spiral-CT angiography (SCTA) was the first-line imaging study for suspected PE in 56% of hospitals, followed by echocardiography and V/P scintigraphy. Lower extremity venous imaging (47%) and, interestingly, V/P scintigraphy (43%), served as second-line imaging tests. D-dimer tests were included in the diagnostic strategy in 74% of hospitals. Spiral-CT angiography is the most commonly used primary method for suspected PE in Austrian hospitals. The V/P scintigraphy is available only in a minority of hospitals to investigate patients with suspected PE. When V/P scintigraphy is available, however, it is employed in a large number of patients per annum.

[Certification according to ISO 9001--waste of time or necessity?]

Quality management (QM) systems are widely established management tools in the industry and business world today. In the health care sector, the need for quality, the implementation of quality management systems and economic orientation of the hospital management are strongly encouraged. Centers of excellence are created to offer special medical services of the highest possible quality. Furthermore, there is a worldwide tendency to establish standards in clinical medical settings, in teaching profession and medical science. These trends make the implementation of a quality management system in health care system highly desirable. The present manuscript reviews the fundamental principles and concepts and the aims of internationally accepted QM systems. It focuses on the ISO-9000 certificates and the European Foundation of Quality Management (EFQM) model. The advantages and disadvantages are discussed. The resources necessary for installation of a QM system and the different phases of implementation are reported. According to the experience of several groups, QM systems can be reliably used in a radiology department and lead to continuous improvement of the quality of services.

Spiral computed tomography of pulmonary embolism

Within the last several years, spiral computed tomography angiography (SCTA) of the pulmonary arteries has emerged as a noninvasive angiographic modality for the evaluation of patients with suspected pulmonary embolism (PE). SCTA is based on continuous computed tomography (CT) data acquisition during patient transport through the rotating X-ray tube and detector system, where scanning is performed in the time period in which the injected contrast material passes through the pulmonary arteries. Single detector spiral CT has a sensitivity of approximately 85-90% and a specificity between 88-95%. Sensitivity and specificity are very likely to increase with the use of multidetector spiral CT scanners that allow scanning of large lung volumes with a scan collimation as narrow as 1 mm. Currently, SCTA is most commonly used as a primary imaging method in patients with suspected PE, and as a second-line method in cases with inconclusive ventilation/ perfusion scintigraphy results. SCTA has proven to be cost-effective, especially in combination with ultrasound of the lower extremities. Limitations of the method include a decreased sensitivity for the detection of small isolated clots in the peripheral pulmonary arterial bed, and a potentially reduced image quality in patients with coexistent cardiopulmonary disorders. Despite these limitations, several studies have now documented that, in patients with suspected pulmonary embolism, it is safe to withhold anticoagulation therapy if a spiral computed tomography exam of the pulmonary arteries is negative and no lower extremity venous thrombosis is present. In the future, multislice computed tomography scanning of the pulmonary arteries with multiplanar reformation and one-stop shopping, i.e. scanning of the pulmonary arteries and the lower extremity veins in a single session, will further enhance the role of computed tomography angiography in the examination of patients with suspected pulmonary embolism.

Changes in lung parenchyma after acute respiratory distress syndrome (ARDS): assessment with high-resolution computed tomography

The aim of this study was to evaluate the appearance, extent, and distribution of parenchymal changes in the lung after acute respiratory distress syndrome (ARDS) as a function of disease severity and therapeutic procedures. High-resolution computed tomography (HRCT), clinical examination, and lung function tests were performed in 15 patients, 6-10 months after ARDS. The appearance and extent of parenchymal changes were compared with the severity of ARDS, as well as with clinical and therapeutic data. Lung parenchymal changes resembling those found in the presence of pulmonary fibrosis were observed in 13 of 15 patients (87%). The changes were significantly more frequent and more pronounced in the ventral than in the dorsal portions of the lung ( p<0.01). A significant correlation was observed between the extent of lung alterations and the severity of ARDS ( p<0.01), and the duration in which patients had received mechanical ventilation either with a peak inspiratory pressure greater than 30 mmHg ( p<0.05), or with more than 70% oxygen ( p<0.01). Acute respiratory distress syndrome frequently is followed by fibrotic changes in lung parenchyma. The predominantly ventral distribution of these changes indicates that they may be caused by the ventilation regimen and the oxygen therapy rather than by the ARDS.

Lung manifestation in asymptomatic patients with primary Sjögren syndrome: assessment with high resolution CT and pulmonary function tests

The authors studied 37 consecutive patients with primary Sjögren syndrome and normal chest radiographs. Thin-section CT images were analyzed using a semiquantitative grading system. The presence, distribution, and severity of 9 morphologic parameters were assessed. In 34 patients, CT findings were correlated to pulmonary function tests (PFTs). Abnormal high resolution CT (HRCT) findings were seen in 24 of 37 patients (65%): interlobular septal thickening, n = 9; micronodules, n = 9; ground glass attenuation n = 4; parenchymal cysts, n = 5. Intralobular opacities, honey combing, bronchial wall thickening, bronchiectasis, and pleural irregularities were less frequent. Both HRCT and PFTs were normal in 10 patients. Computed tomography was normal in four patients with PFTs that indicated the presence of small airway disease. High resolution CT abnormalities were found in seven patients with normal PFT. The overall correlation between HRCT and PFTs was poor. High resolution CT and PFTs appear to be sensitive for both the early detection of parenchymal abnormalities and a decreases in lung function in asymptomatic patients with primary Sjögren syndrome. However, abnormal HRCT findings do not necessarily indicate a substantial alteration in PFTs.

Quantification of coronary artery calcification in patients with FH using EBCT

BACKGROUND

Calcification of the coronary vessel wall is regarded as a marker of advanced coronary atherosclerosis.

METHODS

To test whether patients with heterozygous familial hypercholesterolemia (FH) exhibit excessive calcification of the coronary vessel wall, we quantified coronary artery calcium in LDL-apheresis treated FH-patients with known severe coronary artery disease (CAD) (n = 10), in patients with moderate hypercholesterolemia and known severe CAD (n = 10), and in asymptomatic controls (n = 10) using electronic beam CT. The total coronary calcium score (Agatston-Score), the number of calcified lesions and the calcified plaque volume were evaluated for this study.

RESULTS

CAD-patients with FH, although on average 10 years younger, had a significantly higher total coronary calcium score (702/2018/2890), number of lesions (34/43/49) and calcified plaque volume (700/1818/2313) compared to patients with CAD only (480/641/1362, 10/16.5/22, 480/588/1209, respectively) and controls (10/47/137, 2/4/10, 15/50/144, respectively). Furthermore, we observed a significant correlation (r = 0.93; P < 0.01) between LDL-cholesterol levels (pretreatment levels of the CAD-FH group) and the total coronary calcium score in all three groups. Our results demonstrate that coronary artery calcification is more extensive in CAD-patients with FH than in CAD-patients with moderate hypercholesterolemia. In addition, we provide evidence that the amount of calcium in the coronary vessel wall in FH patients result from a long lasting history of elevated LDL-Cholesterol levels.

CONCLUSION

These findings emphasize the significance of LDL-cholesterol as a risk factor for atherosclerosis and underline the importance of early diagnosis of CAD and early cholesterol lowering therapy in FH patients.

Acute pulmonary trunk dissection in a patient with primary pulmonary hypertension

Spiral CT imaging findings including multiplanar reconstructions of an acute dissection of the pulmonary trunk in a 22-year-old female patient with primary pulmonary hypertension (PPH) are presented and discussed.

Bronchobiliary fistula after hemihepatectomy: cholangiopancreaticography, computed tomography and magnetic resonance cholangiography findings

A bronchobiliary fistula (BBF), which is defined by an abnormal communication between the biliary system and the bronchial tree, is an uncommon complication after hemihepatectomy, trauma, hydatid disease, choledocholithiasis and other causes of biliary obstruction. We report the case of a 56-year-old man with colon cancer, who developed a BBF 2 months after right hemihepatectomy for liver metastases. The findings at endoscopic retrograde cholangiopancreaticography (ERCP), computed tomography (CT) and magnetic resonance cholangiography (MRC) included a stricture of the common bile duct and biliary leakage from the liver resection plane with biliary infiltration of the right lower lobe of the lung. The patient was treated successfully by endoscopic insertion of a biliary plastic stent which bridged the stricture and lead to closure of the fistula.

Cystic fibrosis: CT assessment of lung involvement in children and adults

PURPOSE

To compare a computed tomographic (CT)-based scoring system with nonimaging indexes of pulmonary status in patients with cystic fibrosis.

MATERIALS AND METHODS

Pulmonary CT findings were assessed in 117 patients with cystic fibrosis, with cases classified according to three groups by age; 0-5 years, 6-16 years, and 17 years and older. Images were examined for specific abnormalities, and the severity and anatomic extent of each sign were used to generate a score. Scores in each category and the global score for each patient were correlated with pulmonary function test results, clinical status, serum immunoglobulin levels, and genotype, all obtained within 2 weeks of CT.

RESULTS

The most frequent individual CT abnormalities were bronchiectasis in 94 (80.3%), peribronchial wall thickening in 89 (76.1%), mosaic perfusion in 71 (63.9%), and mucous plugging in 56 (51.3%) patients. The percentage of patients with specific CT findings and the overall CT scores increased significantly (P < .05) with progressively increasing age groups. All CT findings and the overall CT scores correlated significantly (P < .05) with the pulmonary function test results, serum immunoglobulin levels, and clinical scores. No relationship was observed between genotype and CT scores.

CONCLUSION

Scoring of CT studies in patients with cystic fibrosis seems to offer a reliable way to monitor disease status and progression and may provide a reasonable tool to assess treatment interventions.

Thoracic venous anatomy delineated by malpositioned central venous catheters on plain chest films

The aim of this essay was to demonstrate the thoracic venous anatomy as delineated by malpositioned central venous catheters on plain chest radiographs. We therefore used the didactic advantage of clinically inadvertent catheter positions. This approach was chosen to illustrate venous anatomy with plain chest radiographs, and, thereby, to recognize malpositions promptly on the modality with which positions of central venous catheters is routinely performed.

World Wide Web and Internet: applications for radiologists

Global exchange of information is one of the major sources of scientific progress in medicine. For management of the rapidly growing body of medical information, computers and their applications have become an indispensable scientific tool. Approximately 36 million computer users are part of a worldwide network called the Internet or "information highway" and have created a new infrastructure to promote rapid and efficient access to medical, and thus also to radiological, information. With the establishment of the World Wide Web (WWW) by a consortium of computer users who used a standardized, nonproprietary syntax termed HyperText Markup Language (HTML) for composing documents, it has become possible to provide interactive multimedia presentations to a wide audience. The extensive use of images in radiology makes education, worldwide consultation (review) and scientific presentation via the Internet a major beneficiary of this technical development. This is possible, since both information (text) as well as medical images can be transported via the Internet. Presently, the Internet offers an extensive database for radiologists. Since many radiologists and physicians have to be considered "Internet novices" and, hence, cannot yet avail themselves of the broad spectrum of the Internet, the aim of this article is to present a general introduction to the WWW/Internet and its applications for radiologists. All Internet sites mentioned in this article can be found at the following Internet address: http://www.univie.ac. at/radio/radio.html (Department of Radiology, University of Vienna)

[Staging of bronchial carcinoma]

Staging of any tumor, i.e. determination of the extent of the disease, serves to select the patients who might profit from curative surgical intervention or to define those patients with inoperable carcinomas who should be referred for other therapies, such as chemotherapy or irradiation. Furthermore, accurate staging is necessary for assessment of prognosis, for radiation therapy planning, and for differentiation of those with small-cell lung cancer or for follow-up examinations of small-cell lung cancer patients after during and after chemotherapy. The primary radiological staging and diagnostic modalities for assessment of bronchial carcinomas are computed tomography (CT) of the thorax including liver and adrenal glands, abdominal sonography, and bone scintigraphy. Magnetic resonance imaging (MRI) should be reserved for specific indications, e.g. infiltration of the chest wall or staging of patients with intolerance/allergy to intravenous contrast medium. The clinical value of nuclear medicine techniques, such as [18F]2-fluoride-2-desoxy-D-glucose positron emission tomography (FDG-PET) for evaluation of lymph nodes and distant metastases, In-111 octreotide/somatostatin receptor scans for staging of small-cell lung cancer, and thallium-201 SPECT are currently being assessed in numerous studies, although these techniques are already in routine use. In future these or nuclear medicine techniques, as well as techniques using molecular-based contrast material, especially for MR imaging, currently in experimental status, may yield serious potential for staging purposes.

Evolution of CT findings in patients with cystic fibrosis

OBJECTIVE

The aim of our study was to assess the evolution of pulmonary CT findings in cystic fibrosis patients.

MATERIALS AND METHODS

Serial CT examinations were performed in four different follow-up periods on 107 patients with cystic fibrosis. Lung images of the initial and follow-up CT were reviewed and scored for specific morphologic findings. CT findings were correlated with the results of the pulmonary function tests and clinical (Shwachman-Kulczycki) scores.

RESULTS

Morphologic changes were minor within the first 18 months of follow-up compared with the period after 18 months. The increase of the overall score was significantly higher in groups with follow-up periods longer than 18 months compared with groups with follow-up periods shorter than 18 months. Various components of morphologic changes contributed to the sequential changes seen on the CT scans. All morphologic changes and the CT scores correlated significantly (p < .0001) with pulmonary function tests and clinical score. CONCLUSION. Serial CT scans allow assessment of the evolution of pulmonary abnormalities in patients with cystic fibrosis. CT seems to have advantages over pulmonary function tests and clinical scoring in the depiction of pulmonary changes over time.

Spontaneous pneumomediastinum

In this paper two cases of spontaneous pneumomediastinum, occurring in a patient with diabetic ketoacidosis and in a patient with bronchial asthma, are presented. We describe the radiological findings, the differential diagnosis and the important radiographic considerations in establishing the diagnosis. In addition, we discuss the anatomical pathways and review the pathophysiological mechanisms responsible for the development of respiratory spontaneous pneumomediastinum.

[Diagnostic imaging in intensive care medicine. Techniques, indications, diagnostic signs--I]

Die rasant fortschreitenden Entwicklungen auf dem Gebiet der Radiodiagnostik eröffnen auch der Intensivmedizin neue Aspekte: Mittels moderner Technik können heute ungleich rascher konklusive Diagnosen gestellt werden. Dies setzt jedoch die Kenntnis der Möglichkeiten und auch der Grenzen bildgebender Methoden in der Intensivmedizin voraus. Im vorliegenden Beitrag werden, ausgehend von relevanten klinischen Fragestellungen und Problemkomplexen, die Möglichkeiten bildgebender Verfahren vorgestellt und diskutiert. Es werden die wichtigsten diagnostischen Röntgenzeichen erläutert und ein diagnostisches Prozedere vorgezeichnet. Somit soll der vorliegende Beitrag eine kurze Zusammenfassung der für die Intensivmedizin wichtigen Aspekte der Bildgebung darstellen.

Pulmonary alveolar proteinosis in a child: HRCT findings before and after bronchoalveolar lavage

We demonstrate the high-resolution computed tomography (HRCT) findings of pulmonary alveolar proteinosis in a child before and after bronchoalveolar lavage. The CT pattern in our case differs from the pattern described in previous reports. We found a more homogeneous distribution of the pulmonary changes and a "crazy paving" pattern. High-resolution CT may be helpful in the differential diagnosis of this rare disease and in the follow-up of the pulmonary changes after bronchoalveolar lavage.

New-born infants with severe hyaline membrane disease: radiological evaluation during high frequency oscillatory versus conventional ventilation

OBJECTIVE

The aim of our study was to determine the impact of treatment with exogenous surfactant (ES) and high frequency oscillatory ventilation (HFOV) on the radiological appearance and clinical course of hyaline membrane disease (HMD) in new-born infants.

MATERIALS AND METHODS

New-born infants (18) (median weight, 1010 g) with severe HMD (stages 3.5 and 4) who were treated with ES and HFOV were matched by birth weight and severity of disease with 18 new-born infants treated with ES and conventional mechanical ventilation (CV). Chest radiograms taken on days 1, 2/3, 4/5, 7, 14 and 28 were analyzed to check for the severity of generalized parenchymal opacities (GPO), local opacifications, pulmonary interstitial emphysema (PIE), gross air leak, general and localized overinflation, bronchopulmonary dysplasia (BPD) and clinical variables such as survival rates, duration of mechanical ventilation, mean airway pressure and inspired oxygen concentration.

RESULTS

At 4 weeks of age, new-born infants treated by HFOV had less severe GPO (median degree 1.5 vs. 3), less PIE (1 vs. 7 patients) and fewer signs of BPD (median BPD degree 1.5 vs. 2.6). The incidence of pneumothorax and of local opacifications were similar in both groups. New-born infants on HFOV had a lower mortality rate (5 vs. 13), needed fewer days of mechanical ventilation (median 15 vs. 23 days) and lower inspiratory oxygen concentrations (median FiO2 0.38 vs. 0.64).

CONCLUSION

In new-born infants with HMD, treatment with ES and HFOV resulted in a favourable radiological and clinical outcome as compared to treatment with ES and CV.

[Radiologic imaging of thoracic trauma]

Blunt trauma to the chest results from the transfer of kinetic energy to the human body. It may cause a wide range of mostly life-threatening injuries, including fractures of the thoracic skeleton, disintegration of the pleural space, contusion or laceration of pulmonary parenchyma and damage to the mediastinal structures. For a systematic approach it may be helpful to follow an organ-based evaluation of thoracic trauma. However, it should be borne in mind that subtle injuries may be associated with serious complications. Trauma to the chest may affect different anatomic compartments at the same time, requiring an extending diagnostic approach. Conventional radiography plays a major role in diagnosing thoracic trauma, complemented by ultrasound examination of the pleura and abdomen. It is well documented that CT scanning represents a major technological improvement for assessment of thoracic trauma. With the advent of fast helical CT scanning this method becomes more applicable for severely traumatized patients and potentially replaces other time-consuming procedures. State-of-the-art imaging of both projection and cross-sectional techniques provides useful information for immediate and appropriate treatment mandatory in patients with thoracic trauma.

[Spiral CT angiography in diagnosis of acute pulmonary embolism. What factors modify implementation of standard algorithms?]

PURPOSE

Debate about the potential implementation of Spiral-CT in diagnostic algorithms of pulmonary embolism are often focussed on sensitivity and specificity in the context of comparative methodologic studies. We intend to investigate whether additional factors might influence this debate.

MATERIALS AND METHODS

On the basis of the current literature and of own experience we study the influence of factors such as availability, acceptance, patient-outcome, and cost effectiveness-studies on the potential implementation of Spiral-CT in diagnostic algorithms of pulmonary embolism. This information is analyzed together with data from comparative methodologic studies.

RESULTS

The factors availability, acceptance, patient-outcome, and cost-effectiveness-studies do have substantial influence on the implementation of Spiral-CT in the diagnostic algorithms of pulmonary embolism. Incorporation of these factors into the discussion might lead to more flexible and more patient-oriented algorithms for the diagnosis of pulmonary embolism.

CONCLUSION

Availability of equipment, acceptance among clinicians, patient-outcome, and cost-effectiveness evaluations should be implemented into the debate about potential implementation of Spiral-CT in routine diagnostic imaging algorithms of pulmonary embolism.

Severity assessment of acute pulmonary embolism with spiral CT: evaluation of two modified angiographic scores and comparison with clinical data

Spiral computed tomography (CT) has shown promising results in the detection of acute pulmonary embolism. The aim of this study was to investigate whether the severity of acute pulmonary embolism could be quantitatively assessed with spiral CT examinations and to test the potential clinical impact of this information. In a consecutive series of 123 patients screened with spiral CT for suspected acute pulmonary embolism, 31 patients (25%) had evidence of emboli. The severity of pulmonary arterial obstruction in those 31 spiral CT examinations was evaluated by two independent observers using angiographic scores previously described by Walsh (29) and Miller (30), adapted to the needs of spiral CT. Clinical patient subgroups were defined according to oxygen saturation, heart rate, and echocardiographic signs of right ventricular strain. CT severity scores were then correlated to each other and to clinical parameters using the Spearman rank test. Interobserver agreement was calculated using the analysis of variance. Both modified Walsh and Miller scores were readily reproducible and showed interobserver agreements of 0.85 and 0.96, respectively (p = 0.001). Patients with mild and marked clinical abnormalities showed statistically significant differences between CT severity scores. Differences between severity scores of patients with moderate and marked clinical abnormalities were somewhat significant. No significant mean severity score differences were seen between patients with mild and moderate clinical abnormalities. Although correlations of severity scores and detailed clinical parameters within the defined subgroups were moderate to poor, threshold scores greater than 10 (Miller) and greater than 11 (Walsh) always indicated marked clinical abnormalities. The modified scores presented in this study constitute a readily reproducible method for the quantitative assessment of acute pulmonary embolism severity on spiral CT examinations.

Radiographic detection of intrabronchial malpositions of nasogastric tubes and subsequent complications in intensive care unit patients

OBJECTIVE

The aim of our study was to illustrate the radiographic spectrum of the intrabronchial malposition of nasogastric tubes and subsequent complications, and to discuss the role of radiography in the detection of such malpositions.

DESIGN

Retrospective clinical investigation.

SETTING

Tertiary care university teaching hospital.

PATIENTS AND METHODS

We reviewed chest radiographs of 14 intensive care patients with nasogastric tubes malpositioned in the tracheobronchial tree. The site and anatomic location of the malposition were recorded. Complications due to tube malpositioning were monitored on follow-up radiographs and on computed tomographic examinations, which were available in 4 patients.

RESULTS

Nine of 14 nasogastric tubes were inserted in the right and 5 in the left tracheobronchial tree. Tube tips were malpositioned in the lower lobe bronchi (50%), the intermediate bronchus (36%), and the main bronchi (14%). There was perforation of the bronchial system with subsequent pneumothorax in 4 patients. In 4 other patients, pneumonia developed at the former site of the malpositioned tube tip. Radiographic detection of nasogastric tube malpositioning was prompt in 9 patients and delayed in 5 patients.

CONCLUSIONS

Whereas clinical signs of nasogastric tube malpositioning in intensive care patients may be absent or misleading, chest radiography can accurately detect nasogastric tube malpositions in the tracheobronchial tree, may prevent complications, and avoid the use of further costly or invasive diagnostic techniques.

Cylindrical bronchiectasis: diagnostic findings on thin-section CT

OBJECTIVE

The aim of this study was to determine the frequency of diagnostic findings of bronchiectasis on thin-section CT and the usefulness of those findings in distinguishing patients with cylindrical bronchiectasis from healthy subjects.

MATERIALS AND METHODS

The study was retrospective and included 26 healthy adults, 10 consecutive patients with surgically proven cylindrical bronchiectasis, and 49 patients who had been prospectively diagnosed at three institutions as having cylindrical bronchiectasis. All patients had 1.0- to 1.5-mm-collimation CT scans obtained at 10-mm intervals through the chest. The CT scans were independently reviewed in random order by two chest radiologists.

RESULTS

Findings in patients with bronchiectasis that were not seen by either observer in any of the healthy subjects included visualization of a bronchus within 1 cm of the costal pleura and visualization of a bronchus abutting the mediastinal pleura. The two observers saw these findings on 96 (81%) and 63 (53%) of 118 CT scans in the 59 patients with bronchiectasis, respectively. Lack of tapering of bronchi was seen in five (10%) of 52 reviews in healthy subjects compared with 95% of reviews in patients with bronchiectasis. Bronchoarterial ratios greater than 1 were identified in 11 (21%) of 52 reviews in healthy subjects compared with 95% of reviews in patients with bronchiectasis. We calculated good agreement between the two observers (kappa values equal to or greater than .63).

CONCLUSION

In most cases, thin-section CT allows reliable distinction of patients with cylindrical bronchiectasis from healthy subjects.

Bronchoarterial ratio on thin section CT: comparison between high altitude and sea level

PURPOSE

Our goal was to measure normal bronchial to accompanying pulmonary arterial diameter ratios and normal bronchial wall thickness on thin section CT at high altitude and at sea level.

METHOD

Seventeen normal, healthy, nonsmoking subjects living at 1,600 m altitude and 16 living at sea level underwent thin section CT (1.5 to 2.0 mm collimation). All images were photographed at window levels of -450 and -700 HU and window width of 1,500-1,600 HU. Internal diameters of the segmental and subsegmental bronchi were measured and compared with the diameter of the adjacent pulmonary artery. Bronchial wall thickness of each bronchus was measured. Only bronchi and arteries seen in cross section and within 1 mm from each other were included in the analysis.

RESULTS

Four hundred sixty-seven bronchi (215 at high altitude, 252 at sea level) were assessed. At window level of -450 HU, the bronchoarterial ratio was 0.76 +/- 0.14 (mean +/- SD) at altitude and 0.62 +/- 0.13 at sea level (p < 0.001). Bronchial wall thickness measured 0.92 +/- 0.09 mm (mean +/- SD) at altitude and 1.12 +/- 0.19 mm at sea level (p < 0.001). At window level of -700 HU, there was an artifactual decrease in the bronchoarterial diameter ratios and an increase in bronchial wall thickness.

CONCLUSION

Bronchoarterial ratio increases and bronchial wall thickness decreases with altitude. These findings are presumably related to hypoxic bronchodilatation and vasoconstriction.

Association of midoesophageal diverticula with oesophageal motor disorders. Videofluoroscopy and manometry

PURPOSE

To evaluate the prevalence and clinical significance of associated oesophageal motor disorders in patients with midoesophageal diverticula.

MATERIAL AND METHODS

We retrospectively reviewed videofluoroscopic and, if available, manometric studies of 30 patients with midoesophageal diverticula. The type of diverticulum and the presence and nature of oesophageal motor disorders were assessed.

RESULTS

Videofluoroscopy showed that 24 patients had 26 pulsion-type diverticula and 6 patients had 7 traction-type diverticula. Oesophageal motor disorders were demonstrated in 21 of the 24 patients with pulsion-type diverticula and in 3 of the 6 with traction-type diverticula. Nineteen patients had nonspecific motor disorders, 5 had achalasia, and 5 had gastrooesophageal reflux or oesophagitis.

CONCLUSION

Midoesophageal diverticula are most often of the pulsion-type and tend to be associated with an oesophageal motor disorder. Motor disorders are predominantly nonspecific, but achalasia may be encountered as well.

Fast flair imaging of the brain using the fast spin-echo and gradient spin-echo technique

The purpose of this study was to compare the gradient spin-echo (GRASE) to the fast spin-echo (FSE) implementation of fast fluid-attenuated inversion recovery (FLAIR) sequences for brain imaging. Thirty patients with high signal intensity lesions on T2-weighted images were examined on a 1.5 T MR system. Scan time-minimized thin-section FLAIR-FSE and FLAIR-GRASE sequences were obtained and compared side by side. Image assessment criteria were lesion conspicuity, contrast between different types of normal tissue, image quality, and artifacts. In addition, contrast ratios and contrast-to-noise ratios were determined. Compared to FSF, the GRASE technique allowed a 17% reduction in scan time but conspicuity of small lesions in particular was significantly lower on FLAIR-GRASE images because of higher image noise and increased artifacts. Gray-white differentiation was slightly worse on FLAIR-GRASE. Physiological ferritin deposition appeared slightly darker on FLAIR-GRASE images and susceptibility artifacts were stronger. Fatty tissue was less bright with FLAIR-GRASE. With current standard hardware equipment, the GRASE technique is not an adequate alternative to FSE for the implementation of fast FLAIR sequences in routine clinical MR brain imaging.