An Automatic Recognition Algorithm for Feature Points of Photoplethysmography / 医用生物力学

Objective In order to make up for the deficiency in the existing photoplethysmography feature point recognition algorithms which need manually setting the selecting threshold and have poor adaptability to complex waveforms, an automatic reognition algorithm for feature points based on monotonic increase in geometrical characteristics of pulse wave ascending branch was proposed. Methods A ‘reference point’ was determined in each pulse period by zero crossing detection after two Hilbert transformation. The nearest concave and convex inflection points that searched around the ‘reference points’ were the notchs and systolic peaks. Results By using the 18 sets of data in the MIT-BIH standard database for verification, the average sensitivity, precision and detection accuracy reached 99.94%, 99.72% and 99.68%, respectively. Compared with the existing four algorithms, there was a significant improvement in the precision. Feature points could still be accurately identified for complex waveforms. Conclusions The proposed algorithm achieved a higher detection accuracy in the process of searching and determining the position of the pulse wave notchs and systolic peaks, and exhibited a stronger adaptability to the waveform change. The research results provide a good foundation for physiological and pathological analysis through pulse wave features extraction in clinic.

An Automatic Recognition Algorithm for Feature Points of Photoplethysmography / 医用生物力学

Objective In order to make up for the deficiency in the existing photoplethysmography feature point recognition algorithms which need manually setting the selecting threshold and have poor adaptability to complex waveforms, an automatic reognition algorithm for feature points based on monotonic increase in geometrical characteristics of pulse wave ascending branch was proposed. Methods A ‘reference point’ was determined in each pulse period by zero crossing detection after two Hilbert transformation. The nearest concave and convex inflection points that searched around the ‘reference points’ were the notchs and systolic peaks. Results By using the 18 sets of data in the MIT-BIH standard database for verification, the average sensitivity, precision and detection accuracy reached 99.94%, 99.72% and 99.68%, respectively. Compared with the existing four algorithms, there was a significant improvement in the precision. Feature points could still be accurately identified for complex waveforms. Conclusions The proposed algorithm achieved a higher detection accuracy in the process of searching and determining the position of the pulse wave notchs and systolic peaks, and exhibited a stronger adaptability to the waveform change. The research results provide a good foundation for physiological and pathological analysis through pulse wave features extraction in clinic.

The iliac periosteal flap with ascending branch of lateral femoral circumflex artery for the treatment of Legg-Calvé-Perthes disease / 中华显微外科杂志

Objective To investigate the clinical effect of the iliac periosteal flap with ascending branch of lateral femoral circumflex artery for the treatment of Legg-Calvé-Perthes disease.Methods Followed-up 18 patients with Legg-Calvé-Perthes disease who had undergone the treatment of iliac periosteal flap with ascending branch of lateral femoral circumflex artery from January,2008 to May,2012 in our hospital.Minimum follow-up time was from 24 to 60 months,and the average time was 38 months.The followed-up period ended in May,2014.Assessed the effect of surgery by X-ray,clinical examination and Harris scoring system.Results Sixteen patients had good healing with iliac periosteal flap according to X-ray show.Their epiphyseal height recovered and the femoral head rounded gradually.Two cases became flat and collapse.The result of excellent and good rate was 88.9％ by Mose method combined with the results of X-ray.The average Harris hip score improved from 72.3 ± 4.9 points preoperatively to 91.3 ± 2.4 points postoperatively.The difference of the result was statistically significant (P ＜ 0.05).Conclusion The transfer of iliac periosteal flap with ascending branch of lateral femoral circumflex artery is an effective treatment for Legg-Calvé-Perthes disease.

Reconstruction of Trochanteric Pressure Sores using Perforator-based Flap from the Ascending Branch of Lateral Circumflex Femoral Artery

PURPOSE: Trochanteric pressure sores management has been improved through the development of musculocutaneous flaps. But it has many drawbacks such as donor site morbidity and functional muscle sacrifice. With the introduction of perforator flap, it is possible to use in every location where musculocutaneous perforators are present. We have reconstructed trochanteric pressure sores using perforator-based flaps from the ascending branch of lateral circumflex femoral artery. METHODS: Between May of 2006 and April of 2008, we performed six cases of perforator-based flap from the ascending branch of lateral circumflex femoral artery for the coverage of trochanteric pressure sores. For identifying perforators, a line was drawn from the anterior superior iliac spine to the superolateral border of the patella as the vertical axis, from the pubis to the trochanteric prominence as the horizontal axis. In the lateral aspect of the intersection of these two axes, various flap were designed according to its defects. The flap was raised in the subcutaneous plane above the fascia and the pedicle was traced by doppler and identified. The pedicle was meticulously dissected not to injure the periadventitial tissues and transposed to the defect. The donor site was closed primarily. RESULTS: The mean age of patients was 56.2 years. Four male and two female patients were studied. Five patients were paraplegic. The mean defect size was 6 x 4 cm. The largest flap dimension was 14 x 7 cm. Donor sites were closed primarily without any complications. All flaps survived completely without necrosis, hematoma or infection. There were no recurrence during the follow-up period. CONCLUSION: Trochanteric pressure sores using perforator-based flap from the ascending branch of lateral circumflex femoral artery can be performed safely and it would be a reliable option for coverage of trochanteric pressure sores with minimal donor site morbidity.

Application of Blocking Ascending Branch of Uterine Arteries in Operation of Hysteromyomas Rejecting by Laparoscope / 医学研究杂志

Objective To investigate blocking ascending branch of uterine arteries in operation of hysteromyomas rejecting by laparoscope.Methods 60 petients(except cervix myoma,intraligamentary myoma,submucosa myoma),randomly devided to reseach group(30 cases)and control group(30 cases).Blocking ascending branch of uterine arteries before rejecting hysteromyomas by laparoscope in reseach group,directly rejecting hysteromyomas by laparoscope in control group.The volumes of blood loss in operation,the duration of operation,postoperative recovery(Time of passing flatus,wound healing,length of stay)were compared between two groups.During the follow-up months,observing hysteromyoma recidivism and improvement of menstruation.Results All patient were rejected hysteromyomas by laparoscope.The volumes of blood loss in research group were less than that in control group(P0.05),All wounds were well healed in both groups,the rate of hypermenorrhea improvement was 100%(26/26)in research group,but That in control group was 80%(16/20),There was significant difference between two group.Conclusions Blocking ascending branch of uterine arteries may obviously decrease the volumes of blood loss in operation of hysteromyomas rejecting by laparoscope,It presents rapider convalescence,higher rate of symptom improvement and less complication operation.

TREATMENT OF MIDDLE AND INFERIOR FEMORAL BONE FRACTURE NONUNION BY THE TRASPLANTATION OF BONE FLAP WITH ASCENDING AND TRANSVERS BRANCH OF THE LATERAL FEMORAL CIRCUMFLEX VESSLES / 中华显微外科杂志

Objective:For further exploring the feasibility,we have treated the middle and infe- rior femoral bone fracture nonunion by the transplantation of bone flap with ascending and transvers branch of the lateral femoral circumflex vessels.Method:The technique,on the basis of anatomical study have been designed to treat the femoral bone fracture nonunion by the transplantation of bone flap with ascending and transvers branch which pedicle was descendant branch of the lateral femoral circumflex vessel.Results:8 cases of middle and inferior femoral fracture nonunion had been treated by this method.At follow-up of 1 year 5 months to 4 years 6 months,the results have been satisfacto- ry.Conclusions:The method of the transplantation of the bone flap with ascending and transvers branch of the lateral femoral circumflex vessel for the treatment of middle and inferior femoral fracture nonunion has the adventages of simplicity,easiness,reliability.