Prospective Diagnostic Study on Perforator Localization of Anterolateral Thigh Flap With Perforator Locator

Study Overview
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Brief Summary
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Oral and maxillofacial region is an important anatomical part of human body, responsible for chewing, swallowing, language, expression, breathing and other physiological functions. The tissue defects in this area not only seriously affect the physiological function, but also lead to facial deformity and aesthetic damage, affecting the quality of life of patients. The anterolateral thigh flap has become one of the main methods for defect repair due to its large tissue volume and high survival rate, and one of the key steps to ensure a high survival rate is the location of the perforator. How to find the perforator more accurately by improving the detection scheme or locating the perforator according to the anatomical structure, and guide the preparation and cutting of the flap, is the main direction of current research. This study intends to conduct a prospective diagnostic phase II clinical study on perforator localization of flap perforator, and explore its effectiveness and accuracy through sensitivity and specificity. In this study, a total of 76 patients with maxillofacial defects caused by tumors, trauma and other reasons requiring anterolateral femoral flap repair were included, and the perforator branch of femoral anterolateral flap was positioned preoperatively by means of perforator positioning device and color Doppler ultrasound. After the anterolateral thigh flap was prepared, the incision was closed in the donor area of the leg, and the flap was transplanted free to the maxillofacial defect area for repair. The sensitivity, specificity, positive predictive value, negative predictive value, distance difference and odds ratio of the two methods were calculated respectively, and the differences of each evaluation index between the two groups were compared, mainly to evaluate the sensitivity and specificity between the two groups.

Official Title
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Prospective Diagnostic Study on Perforator Localization of Anterolateral Thigh Flap With Perforator Locator

Conditions
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Blood Vessel Perforation

Intervention / Treatment
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* Device: perforator locator


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: All patients with oral and maxillofacial defects caused by malignant tumors or trauma require anterior lateral femoral skin flap repair after surgery There is no history of leg trauma and surgery is feasible No clinically significant positive signs were found in physical examination No chronic or current illnesses such as heart, liver, pancreas, spleen, kidney, digestive tract, respiratory, blood, nervous system, etc No abnormalities found in electrocardiogram (ECG) and X-ray film Hepatitis B surface antigen (HBSAg), anti hepatitis C antibody (anti HCV), anti human immunodeficiency virus antibody (anti HIV), and negative Treponema pallidum (TP) No clinically significant abnormalities were found in vital signs, blood routine, urine routine, blood biochemistry, and blood pregnancy tests The patient voluntarily participated in this study and signed an informed consent form Exclusion Criteria Have a history of leg injury or surgery Significant abnormalities in blood routine, heart, lung, liver, and kidney functions, insufficient compensatory function, or severe systemic diseases Pregnant or lactating women, or those planning to conceive within six months Individuals with a history of mental illness who cannot cooperate with the examination Individuals with allergic constitution or known allergies to contrast agent ingredients The patient or guardian refuses to sign a written consent form

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Intervention Model: Single Group Assignment
Interventional Model Description: During CT scan, the patient lay in a supine position on the examination bed, with the patient's toes facing up and fixed with an ankle fixator, the perforator was placed on the outside of the patient's thigh, the base was extended or shortened according to the length of the patient's thigh, and the iliac patella positioning rod was slipped so that the iliac crest positioning rod was located on the anterior superior spine of the patient's iliac and the patella positioning rod was located on the lateral margin of the patient's patella. And mark the anchor point on the skin with a pen, and mark the skin with a pen. After CT examination, the computer carried out three-dimensional reconstruction of blood vessels, and moved the perforating branch locator rod according to the calculated scale to make it correspond to the scale, and marked the corresponding skin position according to the perforating branch locator rod.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: perforator localization<br>CT and color Doppler ultrasound were used to locate the perforating branch of the descending branch of the lateral circumflex femoral artery, and the position of the perforator was compared with real perforator respectively during the operation. | Device: perforator locator<br>* During CT scan, the patient was lying on the examination bed in a supine position, with the patient's toes facing up and fixed with an ankle fixator, the perforator was placed on the outside of the patient's thigh, and the base was extended or shortened according to the length of the patient's thigh, so that the iliac pole was located on the anterior superior spine of the patient's iliac and the patella pole was located on the lateral border of the patient's patella, and the positioning point was marked on the skin with a pen. After CT examination, the position of the perforating branch was displayed after 3D reconstruction of blood vessels by computer, and the position of the perforating branch was calculated using the computer position. The perforating branch positioning rod was moved according to the calculated scale to make it correspond to the scale, and the corresponding skin position mark was made according to the perforating branch positioning rod.<br>* Other names: color Doppler ultrasound;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Sensitivity | The percentage of actual perforating branches that are correctly determined as the perforating branches according to this research method (true positive rate) is calculated as follows: number of true positive perforations /(number of true positive perforations + number of false negative perforations) =TP/(TP+FN) | during the operation | 
| Specificity | The percentage of actual no perforations correctly judged as no perforations according to this research method (true negative rate) is calculated as follows: true negative number /(true negative perforations + false positive perforations) =TN/(TN+FP) | during the operation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| positive predictive value | The proportion of true positivity in the number of positive perforations determined by this research method reflects the probability that the subject does have perforations when the diagnostic method to be evaluated is determined to be positive. The calculation formula is as follows: PV+ = number of true positive perforations/total number of perforations =TP/(TP+FP) | during the operation | 
| negative predictive value | The proportion of true negative in the number of negative non-penetrating counts determined by the research method; If the diagnostic method to be evaluated is judged negative, the probability that the subject has no negative is calculated as follows: PV- = number of true negative penetrations/total number of controls =TN/(FN+TN) | during the operation | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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anterolateral thigh flap, locator, computerized tomography, color doppler ultrasound