Comparison of the clinical value of transcranial Doppler ultrasound and computed tomography angiography for diagnosing ischemic cerebrovascular disease

Clinical characteristics of elderly hip fracture patients with chronic cerebrovascular disease and construction of a clinical predictive model for perioperative pneumonia

INTRODUCTION

The recovery of cerebrovascular disease (CVD) will increase the incidence of perioperative pneumonia (POP). However, there is limited research on POP in elderly patients with hip fractures complicated by CVD. Therefore, our research focuses on the following two issues: (1) What are the clinical features of elderly patients with hip fractures combined with CVD? (2) What are the predictive factors for the occurrence of POP in such patients?

HYPOTHESIS

Male, femoral neck fracture and hypoalbuminemia can be predictive factors for the development of POP after hip fracture in CVD patients.

MATERIAL AND METHODS

This is a nested case-control study that included patients aged 65 to 105 years with CVD who had a hip fracture between January 2021 and January 2023. According to the occurrence of POP, they were divided into case group and control group. Collecting data includes demographic information, clinical data, and surgical information. Least absolute shrinkage and selection operator (LASSO) regression and multivariate logistic regression analyses were used to select variables. The constructed predictive model was transformed into a nomogram. Predictive performance was assessed using the area under the receiver operating characteristic curve (AUC), calibration curves and decision curve analysis (DCA).

RESULTS

We ultimately included 714 patients, 69.3% female, with a median age of 80 years. Asymptomatic cerebral infarction (ACI) is the most common CVD (55.7%). More patients developed intertrochanteric fractures than femoral neck fractures (57.1 vs. 42.9%). In total, 606 patients (84.9%) underwent surgery. The most common perioperative complications were anemia (76.9%) and hypoalbuminemia (71.8%). POP (20.0%) was more common preoperatively (89.5%). Factors such as fracture type, surgical wait time, implant used for surgery, and anesthesia type did not differ between the presence or absence of postoperative pneumonia. 143 patients with POP served as the case group. Five hundred and seventy one patients did not develop POP and served as the control group. The predictors of POP were male (OR 1.699,95%CI 1.150-2.511, p<0.05), femoral neck fracture (OR 2.182,95%CI 1.491-3.192, p<0.05), and hypoalbuminemia (OR 3.062, 95%CI 1.833-5.116, p<0.05). This model has good discrimination, calibration, and clinical practicality.

DISCUSSION

In this study, we constructed a clinical prediction model for the occurrence of POP in CVD combined with hip fracture in the elderly, with risk factors including gender, fracture type and perioperative hypoproteinemia. Therefore, we can take effective preventive measures against the occurrence of POP in patients with these factors in our clinical work.

LEVEL OF PROOF

IV; nested case-control study.

Approaches to vascular network, blood flow, and metabolite distribution modeling in brain tissue

The cardiovascular system plays a key role in the transport of nutrients, ensuring a continuous supply of all cells of the body with the metabolites necessary for life. The blood supply to the brain is carried out by the large arteries located on its surface, which branch into smaller arterioles that penetrate the cerebral cortex and feed the capillary bed, thereby forming an extensive branching network. The formation of blood vessels is carried out via vasculogenesis and angiogenesis, which play an important role in both embryo and adult life. The review presents approaches to modeling various aspects of both the formation of vascular networks and the construction of the formed arterial tree. In addition, a brief description of models that allows one to study the blood flow in various parts of the circulatory system and the spatiotemporal metabolite distribution in brain tissues is given. Experimental study of these issues is not always possible due to both the complexity of the cardiovascular system and the mechanisms through which the perfusion of all body cells is carried out. In this regard, mathematical models are a good tool for studying hemodynamics and can be used in clinical practice to diagnose vascular diseases and assess the need for treatment.

Transcranial Doppler versus CT angiography: a comparative analysis for the diagnosis of ischaemic cerebrovascular disease

AIMS

To compare the sensitivity, specificity, accuracy, and clinical usefulness of transcranial Doppler (TCD) ultrasound against computed tomography angiography (CTA) for the diagnosis of ischaemic cerebrovascular disease.

METHODS

A total of 1,183 sites (vascular segments) of 169 patients who had been diagnosed with cerebrovascular disease using digital subtraction angiography (DSA) were evaluated by CTA and TCD for the diagnosis of the arterial lesions.

RESULTS

Lesions were identified in 509 sites and 674 sites did not have lesions according to the DSA examination. Each individual site had higher sensitivity, specificity, and accuracy for TCD than those for CTA, respectively. For all sites, TCD had higher true-positive (p=0.0029) and -negative (p=0.0151) values and fewer false-positive and -negative (p<0.0001 for both) values than those of CTA. The sensitivity, specificity, and accuracy of CTA for all sites to detect lesions were 77%, 88%, and 84%, respectively. The same parameters for TCD were 94%, 97%, and 95%, respectively. The beneficial scores for CTA and TCD to detect lesions were 0-0.795 diagnostic confidence and 0-0.91 diagnostic confidence, respectively. Beneficial scores >0.795 and >0.91 indicated a risk of underdiagnosis of lesions at CTA and TCD, respectively.

CONCLUSIONS

Compared with DSA (reference standard) and CTA, the study underscores the use of TCD in cerebrovascular pathology.