卒中影像学检查绿色通道与能谱计算机断层扫描的应用前景

脑血管疾病是严重危害人类健康的常见病、多发病,具有发病率高、死亡率高、致残率高和复发率高等特点。急性脑血管病是十分严重的急性事件,积极、安全、有效、合理的治疗可降低该病的死亡率和致残率,其中影像学检查是一个十分重要的环节。神经放射科、     

Computational Image Analysis of Nonenhanced Computed Tomography for Acute Ischaemic Stroke: A Systematic Review

BackgroundNoncontrast enhanced computed tomography (NCCT) remains the most common method for brain imaging patients who present acutely with ischaemic stroke. Computational methods may improve NCCT analysis in this context. We systematically reviewed current research.MethodsWe searched 7 medical and computer engineering databases for studies testing computational methods for analysing NCCT in acute ischaemic stroke. Two independent reviewers extracted the following data; computational method, imaging features investigated, test dataset, ground truth comparison, and performance. We critically evaluated studies for risk of bias and applicability using the Quality Assessment of Diagnostic Accuracy Studies tool (QUADAS-2).ResultsFrom 11,235 nonduplicated articles, we full-text reviewed 200 and selected 68 for inclusion. We identified three dominant study types testing a large range of computational methods for: (1) identifying acute ischaemic stroke (n = 42); (2) ischaemic lesion segmentation (n = 6); and (3) automated Alberta Stroke Program Early CT Score (n = 20). Most articles presented small test datasets, poorly documented patient populations, and did not specify the acuity of the CT scans used in development. There was limited validation or clinical testing of computational methods. Automated Alberta Stroke Program Early CT Score methods were the only software systems presented in multiple publications. Critical evaluation was often limited by lack of data.ConclusionsComputational techniques for analysing NCCT in patients with acute ischaemic stroke have not been adequately clinically validated. Further research with larger and more relevant datasets, in addition to better collaboration between clinicians and researchers, is needed to aid more widespread clinical adoption and implementation.     

Accuracy of Pedicle Screw Insertion Using Fluoroscopy-Based Navigation-Assisted Surgery : Computed Tomography Postoperative Assessment in 96 Consecutive Patients

Objective

Two-dimensional fluoroscopy-based computerized navigation for the placement of pedicle screws offers the advantage of using stored patient-specific imaging data in providing real-time guidance during screw placement. The study aimed to describe the accuracy and reliability of a fluoroscopy-based navigation system for pedicle screw insertion.

Methods

A total of 477 pedicle screws were inserted in the lower back of 96 consecutive patients between October 2007 and June 2012 using fluoroscopy-based computer-assisted surgery. The accuracy of screw placement was evaluated using a sophisticated computed tomography protocol.

Results

Of the 477 pedicle screws, 461 (96.7%) were judged to be inserted correctly. Frank screw misplacement [16 screws (3.3%)] was observed in 15 patients. Of these, 8 were classified as minimally misplaced (≤2 mm); 3, as moderately misplaced (2.1-4 mm); and 5, as severely misplaced (>4 mm). No complications, including nerve root injury, cerebrospinal fluid leakage, or internal organ injury, were observed in any of the patients.

Conclusion

The accuracy of pedicle screw placement using a fluoroscopy-based computer navigation system was observed to be superior to that obtained with conventional techniques.     

Assessment and prediction of outcome for a brief behavioral insomnia treatment program

This study examined (a) the efficacy, and (b) predictors of outcome of a brief (one to four sessions) behavioral treatment program for chronic insomnia. A total of 103 insomnia patients were treated, and outcome was assessed by a follow-up questionnaire. Outcome variables, including both nocturnal sleep parameters and measures of daytime functioning, showed significant improvement subsequent to treatment. Pretreatment sleep hygiene practices were significantly correlated with daytime fatigue and sleep latency outcome factors. Pre-and post-treatment complaints of daytime fatigue were associated with somatic complaints in general, but not with nocturnal sleep variables. Explanatory hypothesis are discussed.     

Anterior ischemic stroke: Analysis of the multivariable CT-based models for prediction of clinical outcome

ObjectiveTo determine the predictive value of multiple CT-based measurements, individually and collectively, including arterial collateral filling (AC), tissue perfusion parameters, as well as cortical venous (CV) and medullary venous (MV) outflow, in patients with acute ischemic stroke (AIS).MethodsWe retrospectively reviewed a database of patients with AIS in the middle cerebral artery distribution, who underwent evaluation by multiphase CT-angiography and perfusion. AC pial filling was evaluated using a multiphase CTA imaging. The CV status was scored using the adopted PRECISE system based on contrast opacification of the main cortical veins. The MV status was defined by the degree of contrast opacification of medullary veins in one cerebral hemisphere as compared to the contralateral hemisphere. The perfusion parameters were calculated using FDA-approved automated software. A good clinical outcome was defined as a Modified Rankin Scale of 0-2 at 90 days.ResultsA total of 64 patients were included. Each of the CT-based measurements could predict clinical outcomes independently (P<0.05). AC pial filling and perfusion core based models did slightly better compared to each of the other models (AUC = 0.66). Among models with two variables, the perfusion core combined with MV status had the highest AUC=0.73 followed by a combination of MV status and AC (AUC=0.72). Multivariable modeling with all four variables resulted in the highest predictive value (AUC=0.77).ConclusionThe combination of arterial collateral flow, tissue perfusion, and venous outflow provides a more accurate prediction of clinical outcome in AIS than each variable alone. This additive effect of these techniques suggests that the information collected by each of these methods only partially overlaps.     

Body temperature correlates with functional outcome and the lesion size of cerebral infarction

INTRODUCTION: Experimental studies have demonstrated that mild hyperthermia exacerbates ischemia-induced neuronal injury. MATERIAL AND METHODS: We examined the relationship between body temperature and functional outcome in 183 patients suffering from cerebral infarction, and admitted within 24 h from the onset of stroke. Patients' functional capacities in daily life were evaluated by Rankin's score before the attack (RS0), on the day of admission (RS1), and 3 months after the onset of stroke (RS90). RESULTS: RS90 showed an independent correlation with RS0, RS1, age, infarct size and maximum body temperature recorded within the first 7 days from the onset of stroke by multivariate analysis. History of previous cerebrovascular accidents, atrial fibrillation, hemorrhagic transformation, infection, and a hypothalamic lesion showed significant associations with RS90 by the Mann-Whitney U-test, but not by multivariate analysis. Infarct size correlated with body temperature, atrial fibrillation, and hemorrhagic transformation. CONCLUSION: Body temperature correlated well with both functional outcome and infarct size in patients with an acute cerebral infarction.     

Hemiparetic cerebral palsy: clinical pattern and imaging in prediction of outcome

BACKGROUND: Hemiparetic cerebral palsy (HCP) is described as having two main forms: arm-dominant, associated with large cortical/subcortical lesions; leg-dominant, associated with lesions of central white matter. Epilepsy and cognitive deficits are common in the former pattern and rare in the latter. Some authors have recommended routine imaging studies in children with HCP as an assessment of etiology and a predictor of outcome. The present study compares the relative values of clinical analysis and imaging in predicting epilepsy and cognitive disabilities. METHODS: Forty-one consecutive patients with HCP underwent careful clinical assessment and imaging studies (primarily computed tomography) and were followed prospectively for the development of recurrent afebrile seizures and academic difficulties. RESULTS: Twenty of the 41 patients (48.8%) were arm-dominant, 14/41 (34.1%) leg-dominant, and 7/41 (17.1%) proportional (arm = leg). The principal imaging findings were: arm-dominant patients - large arterial infarcts, porencephalic cysts, brain malformations; leg-dominant - periventricular leukomalacia; proportional - porencephaly. Arm-dominant hemiparesis and radiologic evidence of cortical pathology were both predictive of cognitive deficits (odds ratios 14.2 [95% CI 2.6, 75.8] and 5.7 [95% CI 1.4. 22.3] respectively). For the development of epilepsy, both evaluation techniques were again predictive, with imaging findings of cortical pathology being particularly powerful (clinical pattern OR 18.0 [95% CI 3.0, 107.7]; imaging OR 80.7 [95% CI 8.5, 767.3]). CONCLUSIONS: In this study, the clinical pattern of HCP and the radiological findings were both predictive of outcome, with absence of cortical pathology on imaging being particularly predictive for the absence of epilepsy. While the clinical pattern, in isolation, appears helpful in predicting outcome, our results suggest that both evaluation tools have important roles to play in the evaluation of HCP patients.     

Evoked potentials in suspected multiple sclerosis: diagnostic value and prediction of clinical course

Pattern visual, somatosensory and brainstem auditory evoked potentials (EPs) of 14 patients with definite multiple sclerosis, 222 patients suspected of having multiple sclerosis, 26 patients with isolated optic neuritis and 40 patients with a chronic not diagnosed neurologic disorder, were compared with their clinical diagnoses on 2 1/2-year follow-up. In the MS suspects, an EP abnormality demonstrating a clinically silent lesion in any modality (65 patients) was associated with a 71% chance of clinical deterioration (48% chance of definite MS within the follow-up period). Normal EPs (121 patients) were associated with a 16% chance of deterioration (4% chance of definite MS). EPs in patients in whom the only abnormalities confirmed known lesions (36 patients) did not predict follow-up status. Visual EPs demonstrated clinically silent lesions more frequently than somatosensory and auditory EPs (22%, 12% and 5% of patients). Only one of the patients with optic neuritis and 3 of the chronic not diagnosed group had EPs demonstrating clinically silent lesions. CSF and NMR studies also correlated with follow-up in subseries of the patients.     

Cystic Necrosis of the Cervical Spinal Cord: Computed Tomography and Magnetic Resonance Correlation

Compression of the cervical spinal cord may lead to necrosis, which can manifest itself as the so-called snake eyes appearance on computed tomography-myelography. As demonstrated by the case presented here, similar findings can be obtained by magnetic resonance imaging. We can expect this to become a more common finding, not only because the use of magnetic resonance imaging has become more widespread, but also because of the noninvasive nature of this modality, in contrast to computed tomography-myelography.     

A Comprehensive Analysis of the Association of Psoas and Masseter Muscles with Traumatic Brain Injury Using Computed Tomography Anthropometry

ObjectivePsoas and masseter muscles are known markers of sarcopenia. However, the relative superiority of either muscle as a marker is unclear. Therefore, this study analyzed the two muscles in patients with a prognosis of traumatic brain injury (TBI). MethodsPatients with TBI visiting a regional trauma center between January 2017 and December 2018 were selected, and their medical records were reviewed. TBI patients with an abbreviated injury score (AIS) of 4 or 5 were selected. Patients with an AIS of 4 or 5 at the chest, abdomen, and extremity were excluded. Patients with a hospital stay of 1 to 2 days were excluded. Both muscle areas were measured based on the initial computed tomography. The psoas muscle index (PMI) and the masseter muscle index (MMI) were calculated by dividing both muscle areas by height in meters squared (cm²/m²). These muscle parameters along with other medical information were used to analyze mortality and the Glasgow outcome scale (GOS). ResultsA total of 179 patients, including 147 males (82.1%), were analyzed statistically. The mean patient age was 58.0 years. The mortality rate was 16.8% (30 patients). The mean GOS score was 3.7. Analysis was performed to identify the parameters associated with mortality, which was a qualitative study outcome. The psoas muscle area (16.9 vs. 14.4 cm², p=0.028) and PMI (5.9 vs. 5.1 cm²/m², p=0.004) showed statistical differences between the groups. The PMI was also statistically significant as a risk factor for mortality in logistic regression analysis (p=0.023; odds ratio, 0.715; 95% confidence interval, 0.535–0.954). Quantitative analyses were performed with the GOS scores. Bivariate correlation analysis showed a statistically significant correlation between PMI and GOS scores (correlation coefficient, 0.168; p=0.003). PMI (p=0.004, variation inflation factor 1.001) was significant in multiple regression analysis. The masseter muscle area and MMI did not show significance in the study. ConclusionLarger PMI was associated with statistically significant improved survival and GOS scores, indicating its performance as a superior prognostic marker. Further analyses involving a larger number of patients, additional parameters, and more precise settings would yield a better understanding of sarcopenia and TBI.     

Occipital lobe epilepsy: clinical characteristics, surgical outcome, and role of diagnostic modalities

PURPOSE: To assess the role of various diagnostic modalities, to identify surgical prognostic factors and concordances with presurgical evaluations, and to characterize the clinical features of occipital lobe epilepsy (OLE), we studied 26 patients who were diagnosed as having OLE and underwent epilepsy surgery. METHODS: Diagnoses were established by standard presurgical evaluations, which included magnetic resonance imaging (MRI), fluorodeoxyglucose-positron emission tomography (FDG-PET), ictal single-photon emission computed tomography (SPECT), scalp video-EEG monitoring, and intracranial EEG monitoring. After epilepsy surgery, patients were followed up for >2 years. RESULTS: Sixteen (61.5%) of the 26 became seizure free after surgery, and another eight patients had a favorable outcome. Sixteen of the 26 patients experienced a type of visual aura (i.e., visual hallucination, visual illusion, blindness, or a field defect). Nine patients had both automotor seizures and secondary generalized tonic-clonic seizures at different times. Interictal EEG showed correctly localizing spikes in 10 of the 16 patients who became seizure free, and in three of the 10 non-seizure-free patients. MRI correctly localized the lesion in seven of these 16 seizure-free patients, and in three of the 10 non-seizure-free patients. FDG-PET correctly localized the lesion in eight of the 16 seizure-free patients, and in three of nine non-seizure-free patients. Ictal SPECT was performed in 19 patients and correctly localized the lesion in only three of 12 seizure-free patients, and in four of seven non-seizure-free patients. Ictal EEG correctly localized the lesion in 13 of the 16 seizure-free patients, and in five of the 10 non-seizure-free patients. No significant relation was found between the diagnostic accuracy of any modality and surgical outcome. The localizations of epileptogenic zones by these different diagnostic methods were complementary. The concordance of three or more modalities was significantly observed in seizure-free patients (p = 0.042). However, no definite relation was observed between the presence of lateralizing clinical seizure manifestation and surgical outcome (p = 0.108). CONCLUSIONS: Some specific auras indicated an occipital epilepsy onset. Various diagnostic methods can be useful to diagnose OLE, and a greater concordance between presurgical evaluation modalities indicates a better surgical outcome.