Bovine pericardium versus homologous sclera as a wrapping for hydroxyapatite orbital implants

PURPOSE: To report our experience with bovine pericardium as a wrapping material for hydroxyapatite orbital implants after enucleation and to compare the exposure rates of the implants wrapped with bovine pericardium versus donor sclera. METHODS: We retrospectively reviewed the records of all patients who received bovine pericardium-wrapped or donor sclera-wrapped hydroxyapatite implant after primary enucleation between March 1995 and December 2001. RESULTS: Of the 26 patients who received donor sclera-wrapped implants after enucleation, 1 (3.8%) had implant exposure. Of the 26 patients who received bovine pericardium-wrapped implants after enucleation, 6 (23%) had implant exposure. The incidence of implant exposure with the use bovine pericardium wrapping material was found to be significantly higher than with sclera (P = 0.05). Six of the 7 implant exposures were noted in the first 6 months after placement of the orbital implant. Five of the 6 exposed bovine pericardium-wrapped hydroxyapatite implants were associated with socket infection. The case of exposure of the sclera-wrapped implant was treated conservatively by observation. Six patients who had exposure of bovine pericardium-wrapped implants required multiple repairs because of recurrent exposures. Four of these patients eventually required removal of the implant. CONCLUSIONS: Despite the advantages of using bovine pericardium as a wrapping material for hydroxyapatite orbital implants, we observed a significantly higher incidence of exposure with bovine pericardium compared with donor sclera in the early postoperative period. Use of bovine pericardium as a wrapping material for orbital implants should be avoided unless some future modifications of the technique can be developed to prevent such complications.     

Use of bovine pericardium as a wrapping material for hydroxyapatite orbital implants

AIM: To present the results of 27 patients who had enucleation for malignant melanoma of the choroid with hydroxyapatite implant wrapped in bovine pericardium. METHOD: A retrospective study was performed on 27 patients, 12 males and 15 females, who had enucleation as a primary treatment for their choroidal melanomas. The patients were followed up at 1 week, 1 month, 3 months, and then every 6 months. A conformer was fitted at 1 week and an artificial eye at 1 month. The average follow up was 1.7 years. RESULTS: No patient had extrusion of the implant. One patient needed repair of the wound, two patients required a lateral tarsal strip, and one patient developed a conjunctival granuloma, which did not need excision. In one patient there was shallowing of the inferior fornix. The cosmetic results and ocular movement were satisfactory in all but one patient. CONCLUSION: Use of bovine pericardium as wrapping material for the hydroxyapatite implants has shown promising results with minimal extrusion rates providing an effective alternative for sclera, eliminating the potential risks of CJD.     

Bovine pericardium versus homologous sclera as wrapping materials for hydroxyapatite ocular implants: an animal study.

PURPOSE: We compared bovine pericardium and homologous sclera as wrapping materials for hydroxyapatite (HA) ocular implants in enucleated New Zealand white rabbits. METHODS: Eighteen rabbits were unilaterally enucleated and the sockets implanted with 10-mm HA spherical implants. Six implants were wrapped with homologous sclera, 6 with bovine pericardium, and 6 were not wrapped. The rabbits were killed 7 weeks later and the sockets were examined clinically for inflammation and implant exposure. Exenterated specimens were assessed histopathologically for inflammation and vascularization. RESULTS: No clinical evidence of implant exposure or extrusion was detected in rabbits receiving sclera or bovine pericardium wrapped implants. Histopathologically, the bovine pericardium displayed more inflammation in its outer portion, as well as more disruption of its lamellar arrangement than did the sclera. Fibrovascular in-growth was complete in all wrapped implants. CONCLUSION: Bovine pericardium behaves similar clinically to homologous sclera as a wrapping material for spherical HA ocular implants in a rabbit model, and may represent a reasonable alternative to sclera in such procedures in humans.     

Auricular cartilage versus donor sclera as a wrapping of hydroxyapatite orbital implants

AIM: To retrospectively compare postoperative outcomes after primary enucleation and placement of a hydroxyapatite(HA) implant without wrapping, wrapped with auricular cartilage or donor sclera. METHODS: Medical records of patients presented as intraocular tumor or severe ocular injury were identified from the electronic medical record system. Cases underwent enucleation and HA orbital implantation were enrolled in this study and were divided into 3 groups according to the wrapping material of HA implant. Cases with autogenous cartilage caps were enrolled in group A(n=11), with donor sclera caps in group B(n=12), and without any wrapping material in group C(n=9). Follow-ups were set at 1, 2 wk, 1, 3, 6, and 12 mo after surgery.RESULTS: Altogether 32 cases finished the followup and were enrolled in this study. Three cases(27.27%) in group A, 4 cases(33.33%) in group B, and 4 cases(44.44%) in group C developed one complication each after surgery. In group A, no HA exposure occurred, but conjunctival inclusion cyst occurred in one and severe conjunctive chemosis in two cases. In group B, one HA exposure occurred, conjunctive inclusion cysts occurred in one, severe conjunctive chemosis occurred in one, and conjunctival granuloma occurred in one case. In group C, one HA exposure occurred, severe conjunctive chemosis occurred in two cases, and conjunctival granuloma occurred in one case. The case of exposure of none-wrapped implant was noted in the first 6 mo after placement of the orbital implant. The case of exposure of donor sclerawrapped implant was noted at the 12 mo after placement of the orbital implant. Both exposure cases were treated successfully with conservative treatment.CONCLUSION: With low incidence of implant exposure and mild complications, auricular cartilage can be a good choice of alternative wrapping material of orbit implant with satisfied outcome.     

Bovine pericardium (Tutopatch) wrap for hydroxyapatite implants

PURPOSE: To evaluate bovine pericardium (Tutopatch) as a wrapping material for hydroxyapatite implants in patients undergoing enucleation for uveal melanoma. METHOD: Prospective cohort study of patients who had enucleation for uveal melanoma between January 2003 and August 2003 were included in the study. Any patient with less than 3 months follow-up was excluded. Enucleation was performed under general anaesthesia followed by insertion of hydroxyapatite implants wrapped in bovine pericardium (Tutopatch). The recti muscles were sutured directly to the wrap. The tenon's capsule and conjunctiva were closed in two layers. A conformer was inserted at 1 week and artificial eye at 2-3 months. The patients were followed up regularly and were assessed for cosmetic result, exposure of implant, and the need for any further surgical procedures. RESULTS: A total of 19 patients (seven male and 12 female) were included in the study. Median age at diagnosis was 63 years (range 38-80 years). Median follow-up was 26 months (range 22-30 months). No patient developed postoperative complications of wound dehiscence. The overall cosmetic result was excellent in all the patients. The rate of postoperative complications compared favourably with published data using other wrapping materials/implants. CONCLUSION: Tutopatch is a safe wrapping material for hydroxyapatite orbital implants in patients undergoing enucleation for uveal melanoma.     

Bovine bone xenograft as orbital implants in rabbit eyes

AIM: To assess the biocompatibility of bovine bone as orbital implants in rabbits. METHODS: Bovine bone graft was used as an ocular im- plant in rabbits to determine whether it could be successfully used in the anophthalmic socket as an alternative to the expensive synthetic alloplastics. Evisceration of eyes with and without bovine bone orbital implantation was performed in the right eyes of 12 New Zealand white rabbits. Group Y (n = 6) was eviscerated without implant, meanwhile Group X (n = 6) was eviscerated with insertion of an orbital implant using bovine bone. Observation was carried out on day 1, day 7, day 14, day 28 and day 42. Serial clinical examination was carried out based on a few fixed criteria, which included rate of infection, implant migration, evidence of wound breakdown and any restriction of intraocular movements. The implanted eyes were then enucleated on day 42. The enucleated eyes were sent for histopathological evaluation to record the type of inflammatory reaction and rate of fibrovascular ingrowth. RESULTS : Serial clinical examination showed presence of mini- mal infection in all eyes, both in Group X (implanted) and Group Y (control) on first postoperative day, which responded well with antibiotics. Infection occurred in the implanted group after first postoperative day, but there was no evidence of orbital migration or extrusion of implant, wound breakdown, restriction of extraocular movement, severe infection or any physical abnormality. Histopathological examination revealed good fibrovascular ingrowth in the implanted group, with minimal rejecting reaction of rabbit eye towards bovine bone implant. CONCLUSION: This study shows that bovine orbital implant has a good biocompatibility in rabbit eyes and its cost is acceptable.     

牛骨异种移植物作为义眼座兔眼眶内植入术

目的:评价以牛骨作为义眼座在兔眼眶内植入的生物相容性。方法:在兔眼中用牛骨作为植入物,观察其生物相容性及其能否取代昂贵的人造植入物。把12只眼球内容摘除术后的新西兰白兔按眶内有没有植入牛骨分为两组:Y组(6只)为眼球摘除术后眶内没有植入牛骨,X组(6只)为眼球摘除术后植入牛骨。对12只新西兰白兔右眼行眼球内容物摘除,其中6例作为实验组行牛骨植入,6例作为对照组不植入。术后1,7,14,28,42d连续观察术眼的感染情况,植入物的移位情况,伤口愈合情况,眼球运动是否受限。术后42d,摘除实验组眼球,行组织病理检查,检测其炎性反应类型以及纤维血管增生情况。结果:连续临床观察显示:试验组和对照组在术后1d都有轻微的炎症反应,抗生素控制有效。试验组有1例在术后1d发生感染。但没有植入物的移位和脱出,没有伤口的裂开和眼球运动受限,也没有严重的感染和畸形出现。组织病理检查显示牛骨纤维生长良好,有轻微的排斥反应。结论:实验表明在兔眼中,牛骨作为义眼座植入有良好的生物相容性,而且其成本较低,易被接受。     

Polytetrafluoroethylene as a wrapping material for a hydroxyapatite orbital implant

PURPOSE: Porous coralline hydroxyapatite orbital implants have been used with great success in anophthalmic sockets. We used a substitute for donor sclera as a wrapping tissue. METHODS: Orbital implants were wrapped with polytetrafluoroethylene (PTFE) instead of homologous donor tissue in five patients after enucleation. RESULTS: The postoperative course was uneventful in three cases. Complications occurred in two cases: one with implant exposure, and one with severe implant infection leading to its eventual removal. CONCLUSIONS: PTFE is inferior to other wrapping tissue.     

Mersilene mesh versus sclera in wrapping hydroxyapatite orbital implants

PURPOSE: To compare Mersilene mesh versus sclera in wrapping hydroxyapatite orbital implants used in primary enucleation. METHODS: In a prospective, randomized, interventional comparative case series, 60 eyes from 60 consecutive patients were included and randomly allocated for primary enucleation and either Mersilene mesh-wrapped hydroxyapatite (MHA) orbital implant (30 cases, 50%) or sclera-wrapped hydroxyapatite (SHA) orbital implant (30 cases, 50%) under general anesthesia. Complete socket examination was performed at 1 week, 1 month, and then every 3 months after surgery. RESULTS: Mean age was not significantly different (P = 0.08) between patients with MHA (36.43 years) and SHA (28.50 years) orbital implants. The most common cause of enucleation was trauma in both groups (P = 0.09). Patients with MHA had significantly (P = 0.005) longer follow-up time (mean, 11.40 months) than those with SHA (mean, 9.40 months). No exposure was found at last follow-up in the MHA group, but one patient in the SHA group had a small exposure (1 x 1 mm) 1 month after surgery that was conservatively treated. There were no significant postoperative soft tissue complications in either group. CONCLUSIONS: Sclera and Mersilene mesh could be used as a wrapping material for hydroxyapatite orbital implants without significant complications. Absence of disease transmission, low cost, and availability are the main advantages of Mersilene mesh.     

兔眼应用聚氨酯电纺丝作为水凝胶义眼台包裹的效果

目的:观察电纺丝(electrospinning)和异体巩膜作为水凝胶(hydrogel)义眼台包裹材料,用于实验兔眼的临床表现及病理组织学变化观察。方法:纯种新西兰兔20只,随机平均分为电纺丝包裹组和巩膜包裹组,行右眼眼球摘除术后。于肌锥内分别置入由电纺丝及异体巩膜包裹的水凝胶义眼台。术后观察眼部表现,于2,4,8,12wk,连同电纺丝或异体巩膜取出义眼台,光镜下观察包裹材料与义眼台的组织病理学改变,包括炎症反应及血管化情况;扫描电镜观察上述组织的超微结构改变。结果:所有动物均完成实验,20只大白兔均进入结果分析。光镜显示,术后2,4,8,12wk时两组植入物纤维血管生长速度基本一致,炎症及异物反应程度类似。电镜显示,早期电纺丝与水凝胶义眼台结合牢固程度强于异体巩膜组。结论:电纺丝结构特殊,纤维间结合较弱,有利于细胞拓展空间,提高了材料的细胞渗透性,作为义眼台包裹材料,较巩膜致密结缔组织更有利于血管化进程。电纺丝有望成为义眼台包裹材料的替代物。     

珊瑚羟基磷灰石Ⅱ期眶内植入

目的：观察眼球摘除后羟基磷灰石眼座二期眶内植入的修复疗效。方法：用珊瑚多孔羟基磷灰石作为二期眶内植入物共253例。结果：随访6个月-15个月均获得良好的效果。并发症少,未发现眶内感染,植入物排出移位现象,结论：珊瑚羟基磷灰石并发症少,是目前眼球摘除后的良好眶内充填材料。     

义眼台植入后结膜囊狭窄时心包膜移植的效果

目的探讨保存的人心包膜移植治疗羟基磷灰石义眼台植入术后结膜囊狭窄的效果。方法羟基磷灰石义眼台植入术后结膜囊狭窄者36例36（眼），行同种异体心包膜移植结膜囊成形术，术后随访观察6-18月，平均11月。结果35眼（97．22％）在30—60天移植的心包膜被结膜覆盖，感染1眼（2．78％），结膜囊狭窄治愈34例（94．44％）。结论保存的心包膜移植治疗结膜囊狭窄取材方便，疗效良好。     

Pericranium grafts for exposed orbital implants

PURPOSE: To report the use of autologous pericranium grafts to cover exposed orbital implants. METHODS: A two-center consecutive case series of exposed orbital implants covered with autologous pericranium grafts. A patch of pericranium was harvested from the parieto-occipital region and was placed over the implant within a pocket between the implant and the Tenon capsule, followed by layered closure of Tenon and conjunctiva. RESULTS: Four patients (2 women, 2 men) with a mean age of 37 years (range, 26 to 45 years) were included in the study. The mean follow-up period was 9.5 months (range, 7 to 12 months). In all cases, there was no recurrence of exposure and no donor site morbidity. A small pyogenic granuloma, arising from the conjunctival suture line, developed in one case. CONCLUSIONS: Autologous pericranium is a useful covering material for exposed orbital implants and may be used as an alternative to frontal periosteum.     

Magnetic orbital implants.

Sixty-six consecutive cases undergoing enucleation with the insertion of the Roper-Hall magnetic implant at the Birmingham and Midland Eye Hospital (BMEH) were followed up to re-establish the rate of extrusion. It was possible to study the records of all 66 patients. An extrusion rate of 1.5% was found.