Bilateral frontalis sling for surgical correction of unilateral and bilateral severe congenital ptosis with poor levator function

Objective@#This study evaluated the functional and cosmetic outcomes after bilateral frontalis sling repair using either expanded polytetrafluoroethylene (ePTFE) or silicone rod for unilateral or bilateral severe congenital ptosis with poor levator function.@*Methods@#This was a non-comparative, interventional case series involving 30 patients with unilateral or bilateral severe congenital ptosis who underwent bilateral frontalis sling repair from February 2012 to November 2018. Medical records including pre- and postoperative photographs were reviewed. The functional and cosmetic outcomes were assessed.@*Results@#There were 15 patients with severe congenital ptosis who underwent ePTFE surgery and 15 patients who had silicone rod surgery. Baseline levator function measured was less than 5 mm in all patients. The mean follow-up duration after surgery was 15.6+6.9 months. Satisfactory eyelid contour was observed in all patients (100%). Postoperatively, all had good to excellent primary eyelid position and effective frontalis action on eyelid elevation. Complications included exposure of the silicone sling material after trauma at the brow area (n=1) and recurrence of ptosis (n=2).@*Conclusion@#Bilateral frontalis suspension in patients with severe congenital ptosis, whether bilateral or unilateral, resulted in excellent functional and cosmetic outcomes using ePTFE or silicone rod.

Hand-sewn expanded polytetrafluoroethylene valved conduit for right ventricular outflow tract reconstruction / 中南大学学报(医学版)

OBJECTIVES@#Due to the lack of large-sized pulmonary valved conduit products in clinical practice, hand-sewn expanded polytetrafluoroethylene (ePTFE) valved conduit has been used for right ventricular outflow tract (RVOT) reconstruction in many heart centers around the world. This study aims to summarize the early results of the ePTFE valved conduit and the sewing technology of the conduit in combination with the latest progress, and to provide a reference for the application of ePTFE valved conduit.@*METHODS@#A total of 21 patients using ePTFE valved conduit for RVOT reconstruction in the Second Xiangya Hospital, Central South University from October 2018 to October 2020 were prospectively enrolled in this study. The age at the implantation of the conduit was 4.3 to 43.8 (median 15.1) years old, with weight of (38.9±4.1) kg. In this cohort, 14 patients underwent re-reconstruction of RVOT, including 12 patients with pulmonary regurgitation at 6.3 to 31.0 (median 13.8) years after tetralogy of Fallot (TOF) repair, and 2 patients with failed bovine jugular vein conduit (BJVC). Seven patients underwent Ross operations. Among them, 3 were for aortic valve stenosis, 2 were for aortic regurgitation, and 2 were for both stenosis and regurgitation. The ePTFE valved conduits were standard hand-sewn during the surgery. The 3 leaflets were equal in size with arc-shaped lower edge of the valve sinus. The free edge of the valve leaflets was straight with the length of about 1 mm longer than the diameter. The height of the valve sinus was 4/5 of the diameter. The junction of the valve leaflet was 3/4 of the height of the sinus. The designed leaflets were then continuous non-penetrating sutured into the inner surface of Gore-Tex vessel to make a valved conduit. Valved conduits with diameter of 18, 20, and 22 mm were used in 2, 9, and 10 cases, respectively. The surgical results, postoperative recovery time, and serious complications were summarized, and the changes of postoperative cardiac function status and hemodynamic status of the conduits were investigated.@*RESULTS@#During the implantation of ePTFE valved conduit for RVOT reconstruction, 2 patients underwent mechanical mitral valve replacement with Ross operation, 2 patients with pulmonary regurgitation with repaired TOF underwent left and right pulmonary artery angioplasty, and 1 patient with failed BJVC underwent tricuspid valvuloplasty. The cardiopulmonary bypassing time for patients underwent re-reconstruction of RVOT was (130.9±16.9) min, with aorta clamping for 1 patient to repair the residual defect of the ventricular septum. The cardiopulmonary bypassing and aorta clamping time for Ross operation were (242.7±20.6) min and (145.6±10.5) min, respectively. The duration of postoperative ventilator assistance, intensive care unit stay, and hospital stay were 3.5 h to 7.7 d (median 17.1 h),11.2 h to 29.5 d (median 1.9 d), and 6.0 to 56.0 (median 13.0) d, respectively. All patients survived after discharge from hospital. The follow-up rate after discharge was 100% with median time at 15.0 (13.0 to 39.0) months. No death happened during the follow-up. One patient underwent stent implantation due to right coronary stenosis 2 months after Ross operation. One patient underwent balloon dilation due to right pulmonary artery ostium stenosis 1 year after re-reconstruction of RVOT. The cardiac function of all patients recovered to NYHA class I 6 months after operation. The peak pressure gradient across the valve measured by transthoracic echocardiography before discharge was (9.4±2.6) mmHg (1 mmHg=0.133 kPa), and (18.3±6.1) mmHg at the last follow-up. There was no significant increase in the gradient during the follow-up (P=0.134). No patient suffered from mild or more pulmonary regurgitation.@*CONCLUSIONS@#Hand-sewn ePTFE valved conduit is feasible for RVOT reconstruction. It is a promising material for RVOT reconstruction which can effectively meet clinical need. In our experience, the ePTFE valved conduit is simple to manufacture with satisfactory early outcomes.In the application of ePTFE valved conduit, attention should be paid to implantation indications and postoperative anticoagulation management, especially to the preparation details of the valved conduit, to obtain better function and durability of the conduit after implantation.

Application of expanded polytetrafluoroethylene combined with autologous costal cartilage in rhinoplasty / 中华医学美学美容杂志

Objective:To investigate the effect of expanded polytetrafluoroethylene (E-PTFE) combined with autologous costal cartilage in rhinoplasty.Methods:Forty-two patients who underwent rhinoplasty in the form of E-PTFE combined with autologous costal cartilage in the Department of Plastic Surgery, Jiangsu Province Hospital of Chinese Medicine from January 2017 to December 2018 were selected as the research object. The polytetrafluoroethylene combined with autologous costal cartilage was used for rhinoplasty. The dorsal nasal skin was dissected through an inverted " V" type combined with subalar cartilage incision, and then the costal cartilage was cut into appropriate cartilage slices to build the nasal tip stent. According to the degree of elevation of the nasal dorsum, the sculpted E-PTFE was placed under the nasal dorsal fascia. The rectus abdominis fascia covered the apex of the nose, and the incision was closed by suture.Results:The nasal appearance of the forty-two patients was significantly improved, with good nasal shape and no serious complications. After 6-12 months of follow-up, 40 cases were satisfacted with the effect of the rhinoplasty, accounting for 95.2%.Conclusions:The use of polytetrafluoroethylene combined with autologous costal cartilage can effectively raise the dorsum of the nose, extend the length of the nose, project the nasal tip in the rhinoplasty. This procedure is accurate and safe, reach a favorable long-term shape and own high satisfaction, and it thus is worthy of popularization in clinic.

Rapid and sutureless anastomosis of artificial vascular replacement of abdominal aorta in dog models using magnetic compression anastomosis technique / 器官移植

Objective To explore the feasibility of rapid and sutureless anastomosis of artificial vascular replacement of abdominal aorta in dog models using magnetic compression anastomosis (MCA) technique. Methods Twelve healthy adult crossbred dogs were evenly divided into the MCA and hand suturing (HS) groups according to the anastomosis method between abdominal aorta and artificial blood vessels. The intraoperative duration of abdominal aorta occlusion, intraoperative condition of anastomotic stoma and postoperative imaging examination of anastomotic stoma were compared between two groups. Results The intraoperative duration of abdominal aorta occlusion in the MCA group was significantly shorter than that in the HS group [(5.2±2.3) min vs. (24.4±4.3) min, P < 0.001]. No anastomotic leakage of blood or anastomotic stenosis occurred in the MCA group during the operation. Intraoperative anastomotic leakage of blood occurred in all of the 6 dogs in the HS group. Among them, 1 dog died of excessive blood loss, and 2 dogs experienced mild anastomotic stenosis due to repeated repair. Postoperative color Doppler ultrasound and angiography showed smooth blood flow at the anastomotic stoma without stenosis or thrombosis in the MCA group. In the HS group, 4 dogs presented with anastomotic stenosis on angiography at postoperative 4 weeks. Conclusions MCA technique may achieve rapid and sutureless anastomosis of artificial vascular replacement of abdominal aorta in dog models, which reduces the incidence of anastomotic complications and accelerates postoperative recovery.

Analysis of related risk factors for infection after expanded polytetrafluoroethylene rhinoplasty / 中华整形外科杂志

Objective@#to investigate the risk factors of postoperative local infection in patients with polytetrafluoroethylene implant in rhinoplasty, and to provide evidence for reducing the risk of postoperative infection.@*Methods@#Retrospective analysis of 923 cases of rhinoplasty implanting ePTFE prosthesis were conducted, those related factors included were as follows: gender, age, operation, history of nasal surgery, nasal pore bulky excessive sebum secretion, cartilage cap on the tip-defining points, columella support, nasal septum cartilage harvest, extend the septum cartilage transplantation, interdomal fat pad resection, adjust the alar cartilage, reduce the ala nasi, severe postoperative swelling, prevention of postoperative infection duration, postoperative folliculitis, nasal vestibular mucosa was damaged postoperative, whether the surgical incision has abnormal healing and so on are being investigated and recorded, all of which were established as multivariate logistic regression model analysis of the risk factors for independent prognosis of postoperative infection.@*Results@#The excessive sebum of the nasal pores, adjustment of the alar cartilage and the postoperative nasal collision are the independent risk factors for postoperative infection(P<0.05).@*Conclusions@#Patients with large nasal pores and sebum secretion are more likely to render infection after operation. Partial separation and partial nasal resection of nasal alar cartilage and postoperative nasal impact will increase postoperative risk of infection.

Comprehensive rhinoplasty with costal cartilarge and e-PTFE / 中华医学美学美容杂志

Objective To explore the comprehensive approach of rhinoplasty using autologous costal cartilage and e-PTFE,and to observe the outcome and possible complications.Methods A 3-4 cm long costal cartilage was taken out mostly from the 6th or 7th rib and then divided into several parts and shapes.Structural reconstruction of the nasal tip was then done with these costal cartilage parts.Radix augmentation was conducted with e-PTFE.Results From Jan.2013 to Sept.2014,48 patients were treated with this method,all females,aged 22-35 years.36 of them had received rhinoplasty before,12 of them received none.Satisfying aesthetic contouring of the nasal tip and dorsum had been achieved in 45 patients.Deviation of the collumella and nostril asymmetry were found in 3 patients.Among all patients,no such complications as pneumothorax,hemothorax,infection,or hemotoma were observed.The scar on the donor site was not obvious.Conclusions Costal cartilage is sufficient,supportive and easily shapable,when applied to the structural reconstruction of the nasal tip,which can meet the demands of patients who prefer more outstanding and delicate nasal tip contouring.

Effects of VIABAHN-Covered Stent and Bypass in Treatment of Lower Limb Arteriosclerosis Occlusion / 天津医药

Objective To evaluate short and medium term therapeutic effects of VIABAHN-covered stent in treat-ment of arteriosclerosis obliterans in lower extremity. Methods Among all 53 cases of arteriosclerosis obliterans in lower extremity with C/D TASC levels, 22 patients underwent VIABAHN-covered stent (stent group), while the other 31 patients were treated with femoral-popliteal artery bypass grafting surgery (graft group). The arterial patency rates were analyzed 3 and 6 months after the two different surgeries. Results The number of arterial patency cases were 28 (90.3%) at 3 months and 26 (83.9%) at 6 months in stent group while it is 22 (100%) at 3 months and 21 (95.5%) at 6 months in graft group. There were no significant differences in the arterial patency rate at 3 months and 6 months between the two different surger-ies (χ2 is 0.808 and 0.760 respectively, P>0.05). Conclusion VIABAHN-covered stent can be used as the preferred treat-ment for arteriosclerosis obliterans of lower extremity.

Autologous nasal septal cartilage combined with expanded-polytetrafluoroethylene in the secondary nasal deformity correction surgery of postoperative cleft lip / 中华医学美学美容杂志

Objective To correct the nasal deformities of cleft lip by expanded-polytetrafluoroe thylene (e-PTFE) combined with autologous nasal septal cartilage.Methods e-PTFE was placed nearby verge of anterior nasal aperture to raise the fundament of nose.Autologous nasal septal cartilage was harvested and combined with e-PTFE to form a sandwich structure.Nasal tip and collapsed nasaI alar were repaired by this method.Results Fifty cases were treated by this method and 42 cases were followed up for about one year.The results were satisfying.The contour of the nose was similar to normal.Only 3 cases were relapsed after one year.Conclusions e-PTFE combined with autologous nasal septal cartilage is an ideal method to correct nasal deformities of cleft lip.

Guided bone regeneration using two types of non-resorbable barrier membranes

INTRODUCTION: Guided bone regeneration (GBR) is a common procedure for the treatment of bone defects and bone augmentation. The non-resorbable barriers are well-documented barriers for GBR because of their stability and malleability. However, few GBR studies have focused on the different types of non-resorbable barriers. Therefore, this study examined the clinical results of different non-resorbable barriers for GBR; expanded polytetrafluoroethylene (e-PTFE) (TR-Gore Tex, Flagstaff, AZ, USA), and high-density polytetrafluoroethylene (d-PTFE) (Cytoplast membrane, Oraltronics, Bremen, Germany). MATERIALS AND METHODS: The analysis was performed on patients treated with GBR and implant placement from January 2007 to October 2007 in the department of the Seoul National University Bundang Hospital. The patients were divided into two groups based on the type of non-resorbable barrier used, and the amount of bone regeneration, marginal bone resorption after prosthetics, implant survival rate and surgical complication in both groups were evaluated. RESULTS: The implants in both groups showed high survival rates, and the implant-supported prostheses functioned stably during the follow-up period. During the second surgery of the implant, all horizontal defects were filled with new bone, and there was no significant difference in the amount of vertical bone defect. CONCLUSION: In bone defect areas, GBR with non-resorbable barriers can produce favorable results with adequate postoperative management. There was no significant difference in bone regeneration between e-PTFE and d-PTFE.

Incorporation by host tissue of two biomaterials used as repair of defects produced in abdominal wall of rats

PURPOSE: Biomaterials may be used as treatment of great abdominal wall defects to avoid tension during repair. In the present research we intended to investigate incorporation type by host tissue of membranes of microbial cellulose (MC), produced by the bacteria Zoogloea sp., and of polytetrafluoroethylene (ePTFE) in abdominal wall defects of rats. METHODS: Sixty male rats Wistar, anesthetized by ketamine (5mg/100g) and xylazine (2mg/100g), were submitted to a rectangular excision (2x3cm) of the abdominal wall, including fascia, muscles and peritoneum and further treated with implants of microbial cellulose (MC Group - 30 animals) or expanded polytetrafluoroethylene ( ePTFE Group- 30 animals). Each group was subdivided in 14th DPO, 28th DPO and 60th DPO Subgroups. RESULTS: Incorporation of biomaterials was observed by wrapping and infiltration by host tissue. It has been found that wrapping associated to infiltration of host connective tissue in implants of ePTFE were present in 100 percent of the observed samples, and this may be responsible for increase resistance to traction. Inversely, wrapping without host tissue infiltration was seen in 100 percent of examined specimens of MC implants. CONCLUSION: Wrapping and host tissue infiltration is seen only in ePTFE implants.

OBJETIVO: Biomateriais podem ser usados como tratamento de grandes defeitos da parede abdominal para evitar tensão durante reparo. Na presente pesquisa pretendeu-se investigar o tipo de incorporação pelo tecido do hospedeiro de membranas de celulose microbiana (CM), produzidas pela bactérias Zoogloea sp., e de politetrafluoretileno (PTFEe) em defeitos da parede abdominal de ratos. MÉTODOS: Sessenta ratos machos Wistar, anestesiados através de cetamina (5mg/100g) e xilazina (2mg/100g), foram submetidos a uma excisão retangular (2x3cm) da parede abdominal, incluindo fascia, músculos e peritoneum e posteriormente tratadas com implantes de celulose microbiana (Groupo CM - 30 animais) ou politetrafluoretileno (Grupo PTFEe - 30 animais). Cada grupo foi subdividido em Subgrupos14º DPO, 28º DPO e 60º DPO. RESULTADOS: Incorporação do biomaterial foi observada através de envoltório e infiltração pelo tecido do receptor. Foi encontrado que o envoltório associado à infiltração de tecido conjuntivo do hospedeiro em implantes de ePTFE estava presente em 100 por cento das amostras observadas, podendo ser responsável por aumento da resistência à tração. Inversamente, envoltório sem infiltração de tecido do hospedeiro foi visto em 100 por cento dos espécimes examinados nos implantes de CM. CONCLUSÕES: Pode-se ser concluído que o envoltório associado à infiltração de tecido do hospedeiro só é vista nos implantes de PTFEe.

The prothesis of the immense abdominal wall defect after resection of malignant tumors / 中华普通外科杂志

Objective To evaluate the repair of the immense abdominal wall defect after resection of malignant tumours occurred primarily in the abdominal wall or that invaded the abdominal wall secondarily. Methods Among the 20 eases, 12 eases were of malignant tumours within abdominal wall (9 eases of rhabdomyosareoma, 3 eases of malignant fibrous histocytoma), 8 eases with the invasion of abdominal wall from malignant turnouts were of retroperitoneal or intraabdominal malignant tumors (3 eases with retroperitoneal malignant tumours, 1 ease of transverse eolon carcinoma, 3 eases with local reeurrenee in abdominal wall of ascending colon carcinoma undergoing fight hemieoleetomy 2～3 years ago, 1 ease with abdominal wall implantation metastasis of renal carcinoma after resection 5 years ago ). Abdominal wall defects left over by resection were repaired with polypropylene and expanded polytetrafluoroethylene (PPePTFE) mesh. The postoperative eomplieation and healing rate were observed. Results Wounds healed by primary intension, with no subeutaneous hydrops, no incision infeetion, dehiscence and hernia, no intestinal adhesion in all eases. The rate of successful repairing for the abdominal defect was 100%. All patients were followed up, the meshes with no rejection, inflammation and incision hernia, no reeurrenee of tumour in the repaired abdominal wall. Conclusion The PP-ePTFE mesh is a favourable repairing material for the abdominal defect after tumour resection, with the advantages of strong tensility, good bioeompatibility.

Polytetrafluoroethylene as a Spacer Graft for the Correction of Lower Eyelid Retraction

PURPOSE: To evaluate the efficacy of porous expanded polytetrafluoroethylene (e-PTFE, Goretex (R) ) containing large pores made with a 21-gauge needle as a graft for the correction of lower lid retraction. METHODS: e-PTFE grafts were implanted between the tarsus and lower lid retractor via a transconjunctival approach with/without amniotic membrane transplantation, or via a transcutaneous approach. Rabbits were examined and assessed for corneal and conjunctival complications and for e-PTFE graft status. Rabbits were sacrificed for a histological study at 8 weeks postoperatively. RESULTS: e-PTFE grafts were uniformly extruded 3 weeks postoperatively in eyelids operated on via the transconjunctival approach. However, rabbits operated on via the transcutaneous approach demonstrated e-PTFE graft retention; in addition, dense fibrovascular ingrowths into the large pores of e-PTFE were observed histologically. CONCLUSIONS: e-PTFE is a good substitute for other graft materials as a spacer in lower lid retraction operations, especially as an interpositional graft using a transcutaneous approach.

Problems of Expanded Polytetrafluoroethylene (Gore-Tex(R)) in Augmentation Rhinoplasty

Augmentation rhinoplasty is one of the most popular aesthetic procedures in Asians. Numerous alloplastic implants have been used, however alloplastic implants may cause many problems in nasal and perinasal areas because of thin soft tissue cover. For these reasons, an ideal implant should be nonpalpable, readily exchangeable and biocompatible. Among these alloplastic implants, Gore-Tex(R) is a polymer of carbon bound to fluorine composed of solid nodes connected by very fine fibers. It has been reported that this material become permeated and surrounded by mature connective tissue, forming a strong supporting envelop for the material, yet the implant is easily removed because of limited tissue ingrowth. Since it's development, Gore-Tex(R) has found many applications in the field of facial plastic and reconstructive surgery. From November, 2001 to December, 2002, Gore-Tex(R) implants were removed from 17 patients due to several problems such as; decreased dorsal height, tip deformity, chronic inflammation. The implants were very hard to remove and coinciding injury of the surrounding tissue were inevitable. An analysis of the length and thickness changes in these removed implants was made. The results showed, decrease in length and thickness with a volume loss averaging, 46.3% in 45x4.0mm implants, 49.3% in 50x5.0mm implants. In view of the experiences of 17 cases of Gore-Tex(R) implants in rhinoplasty, we have concluded that Gore-Tex(R) implants were structurally unstable, fibrovascular tissue ingrowth into pores were minimal, the implants were very hard to remove and the implants caused a postoperative volume reduction. Therefore, Gore-Tex(R) use in augmentation rhinoplasty should be approached with caution.

The Effects of Placement of Silicone Tube and e-PTFE Stent in External Dacryocystorhinostomy

PURPOSE: To determine the surgical results of bicanalicular silicone tube and e-PTFE (expanded polytetrafluoroethylene) stent in external dacryocystorhinostomy without flap. METHODS: Sixteen patients had been placed with bicanalicular silicone tube and e-PTFE stent and 17 patients with silicone tube only in external dacryocystorhinostomy without flap. We examined the presence of epiphora symptom, passage of dye, and inflammatory change or granuloma formation of nasal mucosa at postoperative 1 day, 1 week, 2 weeks, 4 weeks, 8 weeks, 12 weeks, and 24 weeks. RESULTS: Success rate was higher in double stent group (81.3%) than that in control group (76.5%). But there was no statistically significant (difference between two groups. p=0.085). At nasal endoscopic examination, one case (6.3%) of granuloma was noted in double stent group, and two cases (11.8%) in control group. Membraneous obstruction was not observed in double stent group but one case (5.9%) in control group. CONCLUSIONS: In case of structural deteriolation of midface including nasolacrimal duct, placement of bicanalicular silicone tube with e-PTFE stent may be an useful method in external dacryocystorhinostomy without flap.

6 Cases of Expanded PTFE Graft after Abdominal Wall Wide Excision

PURPOSE: Extensive involvement of the abdominal wall or the diaphragm by benign or malignant tumor usually has precluded wide excision. The major reason has been the lack of a satisfactory replacement for the abdominal wall or the diaphragm. When skin and subcutaneous tissues can be preserved, it is possible to restore the abdominal wall or diaphragm by using expanded polytetrafluoroethylene (GORE-TEX soft tissue patch). METHODS: From August 1993 to November 1999, we performed 6 reconstructions of the large abdominal wall or diaphragmatic defects using ePTFE following wide en bloc resection of the abdominal wall or diaphragm. RESULTS: The patients included 4 cases requiring a reconstruction of the abdominal wall. These consisted of one transverse colon cancer invading into the upper abdominal wall, a multiple teratoma recurring in the lower part of the abdominal wall, a recurrent cervix cancer inn the median line of the lower part of the abdominal wall, and an enormous desmoid tumor appearing in the right lower part of the abdominal wall. They were 22, 22, 8 and 4 months respectively after the surgical treatment. Diseases requiring extensive resection of the diaphragm included a case of hepatoma encroaching into the diaphragm and another case of a huge adrenal pheochromocytoma appearing in the right part of the diaphragm. They passed 8 and 4 months respectively following surgical treatment. There were no cases of wound infection or abdominal wall hernia, although seroma occurred in 2 cases (50%). CONCLUSION: In all 6 cases, a good result was achieved by restoring excised tissue using ePTFE graft after wide excision of tumors involving the abdominal wall or the diaphragm. Therefore, it may be possible to use this technique in cases of active excision of tumors that involve an extensive part of the abdominal wall or the diaphragm.

Application of China-made expanded polytetrafluoroethylene in plastic and aesthetic surgery / 中国微创外科杂志

Objective To evaluate the clinical efficacy of China-made expanded polytetrafluoroethylene (ePTFE) in the treatment of facial defects and hollow deformities on the face. Methods Facial augmentation was performed in different sites as the forehead, temple, nose, chin, nosal base and maxilla, respectively, to correct the facial defects and hollow deformities, by using either China-made ePTFE (Experimental Group) or imported ePTFE (Control Group). Postoperative parameters between the two groups were compared. Results The Experimental Group included 16 patients (18 sites), in whom the postoperative follow-up was conducted for 6~9 months. In this group, a secondary infection (in the nose) occurred in 1 patient because the implant was placed too superficially and too close proximity to the incision, and the implant was removed out. Delayed healing of the incision (in the chin) with uncovered implant was found in 1 patient, who was cured by the change of dressing. In the rest of the patients, no obvious allergic, inflammatory or rejection reaction was seen and a good cosmetic result was achieved. The satisfactory rate of this group was 94.4%(17/18). The Control Group included 10 patients (20 sites). The implant was found bared and then removed in 1 patient (in the nose). The satisfactory rate of this group was 91.7%(11/12). There were no statistical differences between the two groups in the wound healing ( ? 2 =1 109, P =0 574), the adverse reaction ( P =1 000), and the clinical efficacy ( P =1 000). Conclusions China-made ePTFE gives histocompatibility as good as imported one. It is suitable for filling the soft tissue and can be used as a safe and economical alternative.

Histopathologic Findings After Experimental Penetrating Keratoplasty Using Expanded Polytetrafluoroethylene(Gore-Tex(R))in Rabbits: Treatment of Corneal Perforation Using Synthetic Materials. Report I

Although there had been many studies for evaluating an usefulness of expanded polytetrafluoroethylene(Gore-Tex(R)) as a temporary treatment of corneal perforation and a supporting skirt of keratoprosthesis, complications and instability of graft had limited the clinical applications. To find histopathologic factors that can contribute to the instability of graft and to try to modify the surgical methods with models of graft, serial examinations including biomicroscopy and histopathology were performed. According to the results, we were able to divide the causes of instability into two categories as a function of time. Epithelial down growth into the interface between graft and cornea with absence of epithelial coverage over the graft may cause leakage from anterior chamber in early period. Absence of fibrovascular invasion into Gore-Tex(R) resulting no cohesion between graft and cornea might be a factor of instability in late period. Based on these results, modification of surgical techniique and models of graft are needed. Several methods of modificiation are suggested in this report.

Experimental Keratoprosthesis Using Expanded PTFE(Gore-Tex(R) as a Supporting Skirt

Although its high successability in numerous corneal diseases, penetrating keratoplasty in certain conditions, such as chemical burn, ocular pemphigoid, Stevens-Johnson syndrome, severe dry eye, and recurrent graft rejection still has had poor outcomes. So far, many keratoprostheses have been developed, but none of them showed consistent successful results. The authors made two models of keratoprosthesis using expanded polytetrafluoroethylene (PTFE) as a skirt and these models were implanted to 30 and 5 rabbit corneas by intralamellar fixation respectively. Expanded PTFE was well-known for its biocompatibility and porous structure which fibrovascular tissue can grow in. However, both of the models extruded from the cornea in all cases and retention period was 1 month in average. These poor results are thought to be mainly due to previously known enzymatic degradation. To obtain better result, modification of the models and surgical techniques are needed. Several possible modifications are described in this article.

Anterior Chamber Tube Shunt to a Surgical Membrane

Ahn et al.(1989) reported that glaucoma tube shunt surgery using 0.1 mm thickness expanded polytetrafluoroethylene(e-PTFE) as a template controlled the intraocular pressure successfully. But it requires the placement of intraluminal suture in the silicone tube to prevent early postoperative hypotony. To overcome this disadvantage, we modified the template by putting the posterior end of the silicone tube between the two-fold e-PTFE membrane and implanted it in 5 refractory glaucoma patients. The intraocular pressure was controlled without complications such as early hypotony, flat anterior chamber, and choroidal detachment.

A tectonic keratoprosthesis using expanded polytetrafluoroethylene as a supporting skirt in humans

A tectonic keratoplasty was performed with a keratoprosthesis using expanded polytetrafluoroethylene as a supporting skirt, on the left eye of a 23-year-old woman who needed an emergency corneal transplantation due to corneal perforation. The keratoprosthesis implanted, consisted of a supporting skirt which was made of expanded polytetrafluoroethylene (PTFE), and an optic portion which was made of polymethylmethacrylate (PMMA). The optic portion and the supporting skirt were attached by cyanoacrylate tissue adhesive (Histoacryl(R)). Two months post-operatively, the keratoprosthesis was extruded, leaving an opacified, vascularized cornea. A penetrating keratoplasty was performed 1 month later. The excised cornea was composed of granulation tissue. To our knowledge, this is the first case of tectonic keratoprosthesis using expanded PTFE as a supporting skirt in humans.