Objective To study the process of hyaluronidase enzymolysis under different condi tions and to provide the basis for clinical application.Methods The experiment of 15 hyaluronic acid products from 10 brands was conducted in vitro with 15 concentrations and 4 dosages of hyaluronidase at 37 ℃ and 24 C.The results of experiment were compared with the clinical observations.Results The duration of enzymolysis was inversely correlated with hyaluronidase concentration.The duration of enzymolysis process reduced 60％ when equal hyaluronidase was used as compared with that when half hyaluronidase was used.The enzymolysis duration could be 24 folds in different products.The enzymolysis time was 2.9 folds at 24 C [24 ℃ was (77.67±35.33) min],compared with that at 37 ℃[37 ℃ was (27.13±11.05) min].It took much more time of enzymolysis in vivo than in vitro for the same product.Conclusions Enzymolysis efficiency is positively correlated with the concentration and dosage of enzyme and inversely associated with the particle size and viscosity.

Objective To search for a good solution for aesthetic beard reconstruction and to explore the effect of the single-hair grafting in beard reconstruction. Methods Under the local anesthesia, a scalp strip (length range from 5～7 cm, width range from 1.0～1.5 cm) was harvested from the back of the head and then was divided into a series of single-hair micrografts. After the slits were made, the grafts were implanted into the holes, parallel to the original beard directions. The donor sites were directly closed. With this method, 18 sparse beard patients and 3 patients with upper lip scars were treated. Results The grafted hairs grew nearly in the direction of normal beard, which achieved 90 %～95 % survival in recipient areas. The patients were satisfied with the results, in which 19 cases received only 1 operation and 2 cases received another repeated operation. Conclusion Beard reconstruction by single-hair grafting technique is a good, safe and effective method.

Objective The mechanism of traditional double-eyelid blepharoplasty is adhering skin to tarsus,by which the skin below the incision could be elevated along with the tarsus and produce the crease.But the anatomic basis of native double-eyelids is not the same,which depends on the connection of levator aponeuroses with muscle and skin.That is,the elevations of tarsus and skin is based on the different branches of levator aponeuroses to skin.According to this,the authors have developed a modified blepharoplasty suturing levator aponeuroses to the obicularis occuli muscle to mimic the native double eyelid.Methods The surgical procedures were modified from traditional surgery.The major improvements were:keeping obicularis occuli muscles intact,dissecting the levator aponeuroses and suturing them together.Since the suturing was performed between mobilized tissues of muscle and aponeurosis,the method was named as "flexible suspension technique".Five-hundred patients were performed with this method.Forty cases randomly selected from them were compared with 40 cases performed with traditional method,and the results were investigated using questionnaire survey.Results The results of the modified surgery were more natural than traditional technique.Majority of patients were satisfactory,whereas 15 cases (3％) had asymmetry,narrowing and even fold loss.All these 15 cases were puffy eyelids.Statistical results indicated that the satisfaction rate was significantly high (P =0.003),and the adverse effects (edema,bruise and scar) were significantly lighter than traditional technique;whereas the asymmetry and fold loss were higher than traditional technique.Conclusions The flexible suspension technique of blepharoplasty can obtain more natural double eyelid appearance,and is suitable for primary blepharoplasty but not applicable for severe puffy eyelids.

Objective To search for a treatment approach for scalp avulsion injury based on the clinical experiences and review of literature.Methods Twenty-six consecutive scalp avulsion cases were involved in the study:15 cases were complete scalp avulsion (5 including forehead skin) and 11 cases were partial scalp avulsion.Cranial bones exposure occurred in 16 cases,11 of which had a size over 4 × 4 cm2.The treatment methods were various:11 cases with microsurgical replantation,9 cases with skin grafting,4 cases with secondary skin grafting followed by multiple drilling of the calvarium,1 case with local flap,and 1 case with free flap.According to the clinical cases and literature reviews,authors tried to search for an optimal protocol.Results Patients with microsurgical replantation achieved the best recovery including hair growth.In case of not qualified or fail to microsurgical replantation,skin graft could be considered as an alterative step,whereas the result of it was no hair growth and usually scar healing.In summary,14 different clinical conditions followed with 10 surgical techniques were concluded in a route chart.Conclusions To achieve the optimal outcomes of scalp avulsion injury,proper techniques should be chosen according to the treatment protocols.

Hyaluronic acid (HA) injections have already been one of most popular cosmetic procedures for around 18 years. However, blindness is one of the most serious complications caused by HA injections. There is still no consensus on the treatment for vision recovery. The efficacy and safety of different delivery administration of hyaluronidase such as retrobulbar injection and endovascular intervention are still controversial so far. Based on current status, prevention is prior to treatment, which is widely recognized in the world. The pathogenic mechanism of blindness induced by filler injection is still not clear, and there exist several theories including the artery embolism, ischaemia, artery spasm and venous involvement, which are all related to the ophthalmic artery and its branches. Therefore, acquiring anatomic knowledge and the relevant parameters will help us prevent to damage the ophthalmic artery and its branches during HA injections. The mechanism, treatment progress and prognosis of blindness caused by HA injections in recent years were analyzed and summarized in this article. We hope it will help the clinician to improve the relevant knowledge about vision loss caused by HA injection, as well as to promote the safety of filler injection.

Hyaluronic acid (HA) injections have already been one of most popular cosmetic procedures for around 18 years. However, blindness is one of the most serious complications caused by HA injections. There is still no consensus on the treatment for vision recovery. The efficacy and safety of different delivery administration of hyaluronidase such as retrobulbar injection and endovascular intervention are still controversial so far. Based on current status, prevention is prior to treatment, which is widely recognized in the world. The pathogenic mechanism of blindness induced by filler injection is still not clear, and there exist several theories including the artery embolism, ischaemia, artery spasm and venous involvement, which are all related to the ophthalmic artery and its branches. Therefore, acquiring anatomic knowledge and the relevant parameters will help us prevent to damage the ophthalmic artery and its branches during HA injections. The mechanism, treatment progress and prognosis of blindness caused by HA injections in recent years were analyzed and summarized in this article. We hope it will help the clinician to improve the relevant knowledge about vision loss caused by HA injection, as well as to promote the safety of filler injection.

BACKGROUNDPancreatic neuroendocrine tumors (pNETs) are a type of tumors with the characteristics of easy metastasis and recurrence. Till date, the risk factors affecting the prognosis are still in the debate. In this study, several risk factors will be discussed combined with our cases and experience.

METHODSThirty-three patients diagnosed as pNETs were enrolled and the clinical features, blood tests, pathological features, surgical treatment, and follow-up data of these patients were collected and analyzed.

RESULTSIn this study, operation time of G3 cases was longer than G1/G2 cases (P = 0.017). The elevated level of tumor markers such as AFP, CEA, Ca125, and Ca19-9 may predict easier metastasis, earlier recurrence, and poor prognosis (P = 0.007). The presence of cancer embolus and nerve invasion increases along with the TNM stage (P = 0.037 and P = 0.040), and the incidence of positive surgical margin increased (P = 0.007). When the presence of nerve invasion occurs, the chance of cancer embolus and lymph node metastasis also increases (P = 0.016 and P = 0.026).

CONCLUSIONSpNETs were tumors with the features of easy recurrence and metastasis and many risk factors could affect its prognosis such as the elevated levels of tumor markers and the presence of nerve invasion, except some recognized risk factors. If one or more of these factors existed, postoperative treatments may be needed to improve prognosis.

Adolescent ; Adult ; Aged ; Female ; Humans ; Male ; Middle Aged ; Neoplasm Recurrence, Local ; diagnosis ; pathology ; Neoplasm Staging ; Neuroendocrine Tumors ; diagnosis ; pathology ; Pancreatic Neoplasms ; diagnosis ; pathology ; Risk Factors ; Young Adult