Software that combines deep learning, 3D reconstruction and CFD to analyze the state of carotid arteries from ultrasound imaging

BACKGROUND

Ultrasound is one of the non-invasive techniques that are used in clinical diagnostics of carotid artery disease.

OBJECTIVE

This paper presents software methodology that can be used in combination with this imaging technique to provide additional information about the state of patient-specific artery.

METHODS

Overall three modules are combined within the proposed methodology. A clinical dataset is used within the deep learning module to extract the contours of the carotid artery. This data is then used within the second module to perform the three-dimensional reconstruction of the geometry of the carotid bifurcation and ultimately this geometry is used within the third module, where the hemodynamic analysis is performed. The obtained distributions of hemodynamic quantities enable a more detailed analysis of the blood flow and state of the arterial wall and could be useful to predict further progress of present abnormalities in the carotid bifurcation.

RESULTS

The performance of the deep learning module was demonstrated through the high values of relevant common classification metric parameters. Also, the accuracy of the proposed methodology was shown through the validation of results for the reconstructed parameters against the clinically measured values.

CONCLUSION

The presented methodology could be used in combination with standard clinical ultrasound examination to quickly provide additional quantitative and qualitative information about the state of the patient's carotid bifurcation and thus ensure a treatment that is more adapted to the specific patient.

Tortuosity and Proximal-Specific Hemodynamics Associated with Plaque Location in the Carotid Bulb Stenosis

BACKGROUND

Atherosclerotic plaque locations in the carotid bulb increasingly have been found to be associated with patterns of ischemic lesions and plaque progression. However, the occurrence of carotid bulb plaque is a complex process. We aimed to investigate plaque characteristics and geometric and hemodynamic parameters among patients with body and apical plaques of the carotid bulb and to identify the mechanism of bulb plaque formation and location.

METHODS

Consecutive patients with single carotid bulb stenosis (50-99%) were enrolled retrospectively. Patients were divided into body and apical plaque groups based on plaque location. Plaque location and characteristics were identified and measured on high-resolution vessel wall magnetic resonance imaging. Geometric parameters were derived from time-of-flight magnetic resonance imaging. Computational fluid dynamics simulations were performed to quantify wall shear stress (WSS) and four associated WSS-based metrics on the plaque side, on the non-plaque side, and in different parts of the lesion. Plaque characteristics and geometric and hemodynamic parameters were compared, and their associations with the plaque location were determined.

RESULTS

Seventy patients were recruited (41 body plaques and 29 apical plaques). WSSplaque values were lower than WSSnon-plaque values for all plaques (median [interquartile range], 12.59 [9.83-22.14] vs. 17.27 [11.63-27.63] Pa, p = 0.001). In a multivariate binary logistic regression, the tortuosity of the stenosed region, the magnitudes of the mean relative residence time, and the minimum transverse WSS in the proximal part of the lesion were the key factors independently associated with plaque location (p = 0.022, 0.013, and 0.012, respectively).

CONCLUSIONS

Plaque formation was associated with the local flow pattern, and the tortuosity and proximal-specific hemodynamics were significantly associated with plaque location in the carotid bulb.

Reduced Facial Swelling and Incision Numbness After Q-Modified Eversion Carotid Endarterectomy in Patients with Severe Carotid Stenosis

BACKGROUND

Carotid endarterectomy, especially eversion carotid endarterectomy (ECEA), is a standard treatment of carotid artery stenosis but continues to have deficiencies. We have described a modified ECEA technique that focuses on the quality of life (QoL), called Q-modified eversion carotid endarterectomy (QCEA). The modifications mainly include the skin incision, surgical approach, and arterial anastomosis. The purpose of the present study was to evaluate the clinical efficacy of QCEA and the QoL of patients after QCEA.

METHODS

We performed a retrospective study of 109 patients were had undergone ECEA or QCEA from October 2016 to December 2017. The data from all interventions were prospectively collected in a dedicated database. The primary efficacy outcome was the composite of any stroke, myocardial infarction, or death through the 1-year follow-up period. The secondary endpoint was the QoL of patients after ECEA or QCEA on the seventh postoperative day, including incision hematoma, incision numbness, facial swelling, and scar length.

RESULTS

QCEA was performed in 41 patients and ECEA in 45 patients. No statistically significant differences were found in operating or clamping time between the 2 groups. The incidence of facial swelling (4.9% vs. 28.9%; P = 0.040) and incision numbness (4.9% vs. 24.4%; P = 0.011) in the QCEA group was significantly lower than that in the ECEA group. The average scar length of the QCEA group was significantly shorter than that of the ECEA group (5.1 ± 1.4 cm vs. 7.6 ± 2.1 cm; P < 0.001). No transient ischemic attack, stroke, myocardial infarction, or mortality occurred in either group during the 1-year follow-up.

CONCLUSIONS

Our results suggest that QCEA can reduce incision numbness, facial edema, and scar length, thereby improving the QoL of patients.

[Postoperative blood pressure alterations after carotid endarterectomy : Implications of different reconstruction methods]

BACKGROUND

Postoperative blood pressure alterations after carotid endarterectomy (CEA) are associated with an increased risk of morbidity and mortality.

OBJECTIVE

To outline the influence of the two commonly used surgical reconstruction techniques, conventional CEA with patch plasty (C-CEA) and eversion CEA (E-CEA), as well as the innovative carotid sinus-preserving eversion CEA (SP-E-CEA) technique on postoperative hemodynamics, taking the current scientific knowledge into consideration.

METHODS

Assessment of the current clinical and scientific evidence on each operative technique found in the PubMed (NLM) database ranging from 1974 to 2017, excluding case reports.

RESULTS

A total of 34 relevant papers as well as 1 meta-analysis, which scientifically dealt with the described topic were identified. The results of the studies and the meta-analysis showed that E‑CEA correlates with an impairment of local baroreceptor functions as well as with an elevated need for vasodilators in the early postoperative phase, whereas C‑CEA and SP-E-CEA seem to have a more favorable effect on the postoperative blood pressure.

CONCLUSION

The CEA technique influences the postoperative blood pressure regulation, irrespective of the operative technique used. Accordingly, close blood pressure monitoring is recommended at least during the postoperative hospital stay. Further studies are mandatory to evaluate the importance of SP-E-CEA as an alternative to the classical E‑CEA.