Image Features of LSCI and Thermography for Prediction of Healing Trajectory in Diabetic Foot Patients Affected by the First (or Successive) Ulcer: (MY-FOOT-B)
试验速览
- 阶段
- 不适用
- 状态
- 撤回
- 发起方
- 主要终点
- Area Under ROC curve generated by the statistical model able to discriminate between healing and not healing ulcers
研究概览
简要总结
The objective of this observational study is to predict healing at 26 weeks after the first visit in patients affected by the first ulcer, by means of combined data monitoring of Laser Speckle Contrast Imaging (LSCI) and temperature measurements during patient visits in hospital.
In order to achieve this objective, study aims to produce a logistic regression model and then evaluate its prognostic ability by means of the area under the curve (AUC) of the receiver-operating-characteristics (ROC) curve.
Patients with diabetes mellitus and suffering from ulcer and receiving health care will undergo regular microcirculatory measurements including LSCI scans in and around the ulcer location and thermography.
详细描述
The study aims to predict healing at 26 weeks after the first visit in patients affected by the first ulcer, by means of combined data monitoring of Laser Speckle Contrast Imaging (LSCI) and temperature measurements during patient visits in hospital.
In order to achieve this objective, the study aims to produce a logistic regression model and then evaluate its prognostic ability by means of the area under the curve (AUC) of the receiver-operating-characteristics (ROC) curve.
The variables evaluated for the model will include demographic and baseline characteristics of the patients, location and seriousness of the ulcer, alongside LSCI and temperature measurements at baseline and different timepoints. The development of the model will include a rigorous variables selection in order to produce a parsimonious model.
In the method proposed by Mennes, LSCI measurements at baseline, biological zero, post occlusion peak, and other parameters like non-invasive blood pressure measurements were individually evaluated as possible prognostic factors of healing trajectory at 26 weeks. All these parameters, when assessed at their highest possible value of sensibility and specificity, produced AUCs always inferior to 0.65. The highest value of AUC (0.625) was reached by toe pressure parameter when calculated using a threshold value of 54 mmHg.
From diagnostic literature, an AUC of ≥ 0.8 is considered excellent result, while an AUC < 0.7 is considered less than acceptable. Since the Mennes's method showed these results, study investigators set the AUC resulting from the model under the null hypothesis (H0) to be equal to 0.65. By including all these parameters, alongside the other mentioned variables, in a single prognostic model, study investigators expect to increase this prognostic ability. Therefore, in this study, investigators would like to detect an AUC ≥ 0.8 (H1). With these hypotheses, a power of 80%, a one-sided I type error of 5% and a prevalence of 43% of healed patients at 26 weeks, a total of 82 patients should be enrolled.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 80 Years（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •a confirmed diagnosis of type 1 or type 2 diabetes mellitus (more than 5 years from diagnosis),
- •aged between 18 and 80 years,
- •patients affected by one foot ulcer (defined as break of the skin of the foot that involves at least the epidermis and part of the dermis )
- •signed informed consent.
排除标准
- •having multiple foot ulcers,
- •having an amputation of the forefoot or an amputation at a more proximal location of the foot (e.g., midfoot or hindfoot),
- •severe foot infection (IWGDF grade 4),
- •being incapacitated or undergoing cancer treatment.
结局指标
主要结局
Area Under ROC curve generated by the statistical model able to discriminate between healing and not healing ulcers
时间窗: at 26 weeks after the first visit in patients affected by the first ulcer
to discriminate between healing and not healing ulcers by means of combined data monitoring of Laser Speckle Contrast Imaging (LSCI) and temperature measurements during patient visits in hospital
次要结局
- The predictive positive and negative value related to the score test, based of calculation of likelihood ratio.(at 26 weeks after the first visit in patients affected by the first ulcer)
- The AUC of the models estimated according to different sites of ulcers.(at 26 weeks after the first visit in patients affected by the first ulcer)