Coralline hydroxyapatite orbital implant (bio-eye): experience with 158 patients

PURPOSE: To assess the problems seen in 158 patients with coralline hydroxyapatite (HA) orbital implants (Bio-Eye). METHODS: A consecutive case series of 170 patients receiving coralline HA implanted by two surgeons over a 5-year period were reviewed. The authors analyzed age, type of surgery, implant size, peg system, follow-up duration, time of pegging, problems encountered, and treatment. RESULTS: Twelve patients were lost to follow-up after 5 months, leaving 158 patients who were followed from 6 to 130 months (average, 39 months). Problems in unpegged implants occurred in 36 (22.8%) patients. Discharge occurred in 18 (11.4%) patients, implant exposure in 12 (7.6%), socket discomfort in 1 (0.6%), conjunctival thinning in 3 (1.9%), chronic conjunctival swelling in 2 (1.3%), and implant infection in 3 (1.9%). Problems after pegging occurred in 68 (50.7%) of 134 patients: discharge in 27 (20.1%), pyogenic granuloma in 24 (17.9%), conjunctiva overgrowing the peg in 4 (3.0%), implant exposure around the sleeve in 5 (3.7%), clicking in 6 (4.5%), peg on an angle in 2 (1.5%), loose sleeve in 1 (0.7%), peg falling out in 18 (13.4%), popping peg in 1 (0.7%), poor transfer of movement in 3 (2.2%), pain with movement in 1 (0.7%), and implant infection in 2 (1.5%). CONCLUSIONS: The Bio-Eye orbital implant represents a porous orbital implant that is biocompatible with orbital tissues and allows fibrovascular ingrowth and improved motility when coupled to the overlying artificial eye. It is more expensive than other commercially available porous orbital implants, such as synthetic FCI3 HA, porous polyethylene (Medpor), and aluminum oxide (Bioceramic) implant. Problems encountered with its use are similar to those problems seen in patients with the synthetic FCI3 hydroxyapatite and aluminum oxide orbital implants.     

The bioceramic orbital implant: experience with 107 implants

PURPOSE: To assess the problems associated with the Bioceramic (Aluminum oxide, Al(2)O(3)) orbital implant. METHODS: A consecutive case series of 107 patients receiving a Bioceramic orbital implant by two surgeons over a 3-year period were reviewed. The authors analyzed patient age, type of surgery, size of implant, peg system, follow-up duration, time of pegging, complications encountered, and treatment. RESULTS: Seven patients were lost to follow-up after 2 months, leaving 100 patients who were followed from 3 to 38 months (average, 13.4 months). Three patients died during the follow-up period (one with 2 months' follow-up, one with 7 months' follow-up, and the third with 9 months' follow-up). Implant-related problems occurred in 11 (11%) patients. Discharge occurred in 5 (5%) patients, implant exposure in 2 (2%), socket discomfort in 1 (1%), trochleitis in 1 (1%), and conjunctival thinning in 2 (2%). Peg problems occurred in 11 (34.3%) of 32 pegged patients: discharge in 4 (12.5%) and in 1 patient (3.1%) each, pyogenic granuloma, conjunctiva overgrowing the peg, implant exposure around the sleeve, clicking, accumulation of black material, and broken peg during insertion. Infection did not occur in any patient. CONCLUSIONS: The Bioceramic orbital implant represents an alternative porous orbital implant that is biocompatible with orbital tissues, easy to manufacture, structurally strong, and less expensive than other commercially available porous orbital implants (e.g., Bio-Eye hydroxyapatite implant). Problems encountered with its use are similar to those seen with the Bio-Eye orbital implants but appear to occur less often. The incidence of exposure associated with the Bioceramic implant is less than that reported for the Bio-Eye.     

Experience with 120 synthetic hydroxyapatite implants (FCI3)

PURPOSE: To assess the problems and/or complications associated with the use of a synthetic hydroxyapatite implant (FCI, Cedex, France). METHODS: The authors analyzed all of the problems and/or complications associated with the use of a third-generation synthetic hydroxyapatite implant (FCI3) in 120 patients by one surgeon over 4 years. The following data were recorded: age, type of surgery performed, size of implant used, peg system used, follow-up duration, time of pegging, problems and/or complications encountered, and treatment. RESULTS: Thirteen patients were lost to follow-up after 3 months, leaving 107 patients who were followed up from 4 to 48 months (average, 29 months). Discharge occurred in 21 (19.6%) patients, implant exposure in 3 (2.8%), socket discomfort in 2 (1.9%), trochleitis in 2 (1.9%), conjunctival thinning in 1 (0.93%), and pyogenic granuloma in 1 (0.93%). Peg problems occurred in 24 (35.2%) of 68 patients. Problems encountered with the peg were discharge in 10 (14.7%) patients, pyogenic granuloma in 9 (13.2%), conjunctiva overgrowing the peg in 4 (5.8%), hydroxyapatite exposure around the sleeve in 3 (4.4%), loose sleeve in 3 (4.4%), peg drilled on an angle in 1 (1.5%), implant infection in 1 (1.5%), and peg falling out in 1 (1.5%). CONCLUSIONS: The FCI3 synthetic hydroxyapatite is a less costly alternative form of hydroxyapatite currently in use in many parts of the world. Problems and complications encountered with its use are similar to those seen with the Bio-Eye Integrated Orbital Implants, Inc., San Diego, CA, U.S.A. The incidence of exposure associated with the synthetic hydroxyapatite implant is lower than several other reports on the Bio-Eye. The synthetic hydroxyapatite implant is slightly softer than the Bio-Eye and fractured under extreme pressure in one case.     

Problems after evisceration surgery with porous orbital implants: experience with 86 patients

PURPOSE: To assess the problems associated with the use of 4 types of porous orbital implant (Bio-Eye coralline hydroxyapatite, FCI3 synthetic hydroxyapatite, aluminium oxide [Bioceramic], and porous polyethylene [Medpor]) after evisceration surgery. METHODS: A retrospective analysis was made of all cases of evisceration with placement of one of four types of porous orbital implants performed between 1991 and 2002 by one surgeon (n = 86). Patient age, implant type and size, surgery type (standard evisceration or evisceration with posterior sclerotomies), peg system used, follow-up duration, time of pegging, problems before and after pegging, and treatment were recorded. RESULTS: Eight patients had less than 6 months of follow-up. The other 78 patients were followed for 6 to 107 months (average, 31 months). The following problems were noted before peg placement: discharge, 8 patients (10.2%); implant exposure, 6 patients (7.7%); implant fracture at the time of surgery, 1 patient (1.3%); persistent pain, 1 patient (1.3%). Of the 29 patients who had pegging, problems including discharge, exposure, pyogenic granuloma, infection, and peg sleeve problems occurred in 23 (79.3%). Sixteen (55.2%) of the 29 patients required at least 1 additional surgical procedure, 4 required 3 additional procedures, and 2 required 5 additional procedures, including implant removal. CONCLUSIONS: Although primary evisceration with posterior sclerotomies and placement of a porous orbital implant is an accepted technique for treating a variety of end-stage eye diseases, patients should be cautioned about an increased likelihood of problems and potential need for additional surgeries if pegging is considered.     

Fibrovascularization of porous polyethylene (Medpor) orbital implant in a rabbit model

PURPOSE: To evaluate the porous polyethylene (Medpor) orbital implant in a rabbit model and compare it with three other currently available porous implants: Bio-Eye coralline hydroxyapatite (HA), FCI(3) synthetic HA, and aluminum oxide (Bioceramic). METHODS: The porous polyethylene implant was examined macroscopically and microscopically (with scanning electron microscopy). Implantation was performed in 10 adult male New Zealand albino rabbits. Each animal underwent enucleation of the right globe under general halothane gas anesthesia, followed by placement of a 12-mm porous polyethylene implant. In 5 animals, the implant was encased in polyglactin 910 (Vicryl mesh); in the other 5, it was left unwrapped. The implants were moistened in saline before placement. Implant vascularization was evaluated by histopathology at 4, 8, 12, 16, and 24 weeks. RESULTS: The porous polyethylene implant was found to have a smoother exterior surface than the Bio-Eye, FCI(3) synthetic HA, and aluminum oxide implants. Rather than a uniform interconnected porous architecture, there was an extensive system of interconnected channels through the implant, ranging in size from 125 to 1000 microm. On high-power examination there was a more solid, woven appearance without any sign of the microcrystals seen in the other porous implants. One rabbit had a retrobulbar hemorrhage after surgery and was euthanized. All the other rabbits tolerated the implant well, and there were no complications. On histopathologic examination, fibrovascularization gradually increased over time. One implant was completely vascularized at 12 weeks, and both implants harvested at 16 weeks were completely vascularized. The implant harvested at 24 weeks showed only partial vascularization (14%). CONCLUSIONS: The porous polyethylene orbital implant represents an alternative implant for use after enucleation or evisceration or for secondary implantation. In our rabbit model, the porous polyethylene implant was well tolerated without complication. Complete fibrovascularization was first seen at 12 weeks. Porous polyethylene orbital implants appear to vascularize more slowly than Bio-Eye coralline HA, FCI(3) synthetic HA, and aluminum oxide implants.     

羟基磷灰石义眼台眶内植入术后结膜脓性肉芽肿形成的原因分析(英文)

目的:分析羟基磷灰石(hydroxyapatite,HA)义眼台眶内植入术后结膜脓性肉芽肿形成的原因。方法:回顾性分析我院眶内植入HA义眼台250例(钻孔及栓钉置入68例),随诊18mo~10a,脓性肉芽肿形成后首先药物保守治疗,无效后采用手术治疗。结果:植入HA义眼台250例中发生脓性肉芽肿10例,其中9例在钻孔及栓钉置入术4~7a后发生,1例发生时羟基磷灰石义眼台未钻孔。9例保守治疗效果均欠佳,行HA义眼台取出术,1例拒绝眼台取出而继续保守治疗。结论:脓性肉芽肿是严重的义眼台植入术后并发症,发生原因可能与义眼台植入后血管化不足,义眼台暴露与继发感染,异体材料包被,义眼台钻孔及栓钉置入等因素有关,而与栓钉的材料无关。脓性肉芽肿的发生意味着义眼台可能发生了感染,最终需行义眼台取出术。     

Primary placement of a hydroxyapatite-coated sleeve in bioceramic orbital implants

PURPOSE: To study a new surgical option of primary placement of a hydroxyapatite-coated sleeve into the Bioceramic implant during enucleation or evisceration. DESIGN: Retrospective, observational case series. METHODS: A standard enucleation or evisceration was performed, followed by the preplacement of a hydroxyapatite-coated sleeve into the Bioceramic implant. Care must be taken to ensure the sleeve has been positioned centrally when the implant is put inside the orbital socket. Complications such as sleeve exposure, Bioceramic implant exposure, and infection were closely observed. RESULTS: Twenty-seven patients were treated in above fashion with five enucleation and 22 evisceration procedures. Five of the sleeves have exposed spontaneously during 1 to 4 months after original surgery. They had no further complication, except for one sleeve around which there were visible Bioceramic spicules attributable to long-term corticosteroid usage. The remaining 22 sleeves that did not spontaneously expose pursued secondary exposure of the sleeve and peg insertion by the conjunctival cutdown procedure 3 months postoperatively. One sleeve was medially positioned far away from the implant center. Re-insertion of new sleeve and peg was scheduled 2 weeks later. One additional sleeve was obliquely positioned after conjunctival cutdown procedure. Fortunately, all 27 patients were successfully fitted with a peg-coupled prosthesis with good motility. CONCLUSIONS: Primary placement of a hydroxyapatite-coated sleeve into the Bioceramic implants has several advantages, including high patient acceptance, technical simplicity, and an office-based conjunctival cutdown pegging procedure. By avoiding the expense of postoperative imaging studies and additional prosthetic modification, a more rapid and efficient rehabilitation is possible.     

Primary placement of a titanium sleeve in hydroxyapatite orbital implants

BACKGROUND: To study a new surgical option of primary placement of a titanium sleeve into hydroxyapatite implants during enucleation or evisceration. METHODS: A standard enucleation or cornea preserved evisceration was performed, followed by preplacement of a titanium sleeve into the hydroxyapatite implant by a hand drill sleeve driver. Care must be taken to ensure that the titanium sleeve is positioned centrally when the implant is put inside the orbital socket or eviscerated shell. The Tenon capsule and conjunctiva were meticulously closed with minimal tension. Complications such as sleeve exposure, coralline exposure, and infection of the titanium sleeve were closely observed. RESULTS: In all, 30 patients were treated in the above fashion with 10 enucleation and 20 evisceration procedures. The follow-up period ranged from 9 to 24 months. Three of the sleeves were found to have exposed spontaneously at 5 and 7 weeks following original surgery. They had no further complication except one sleeve loosening. The remaining 27 sleeves that did not spontaneously expose pursued secondary exposure of the titanium sleeve and peg insertion by conjunctival cutdown procedure 3 months after original surgery. Two sleeves were found to be oblique positioned after the conjunctival cutdown procedure. Fortunately, all the 30 patients were successfully fit with a peg-coupled prosthesis with good motility. CONCLUSION: Primary placement of a titanium sleeve into hydroxyapatite implants has several advantages, including high patient acceptance, technical simplicity, and office-based conjunctival cutdown pegging procedure. By avoiding the expense of postoperative imaging study and additional prosthetic modification, a more rapid and efficient rehabilitation is possible.     

Behavior of various orbital implants under axial compression

PURPOSE: To determine and compare the amount of force required to disrupt the integrity of various orbital implants. METHODS: Compression tests were carried out by using a servo-electrical universal testing system on orbital implants including aluminum oxide (Bioceramic implant, FCI, Issy-Les-Moulineaux, France), coralline hydroxyapatite (HA) (Bio-Eye, Integrated Orbital Implants, Inc., San Diego, CA, U.S.A.), bovine HA (Molteno M-Sphere, IOP Inc., Costa Mesa, CA, U.S.A.), synthetic HA (FCI3, FCI, Issy-Les-Moulineaux, France), Chinese HA (H + Y Comprehensive technologies, Philadelphia, PA, U.S.A.), polylactic acid (Kinsey Nash Corporation, Duluth, MN, U.S.A.), porous polyethylene (Medpor, Porex Surgical Inc., College Park, GA, U.S.A.), and polymethylmethacrylate. RESULTS: Two basic groups of implants were identified: those that eventually reach a critical compression point and collapse (coralline HA, aluminum oxide, synthetic FCI3 HA, bovine HA, Chinese HA, and polymethylmethacrylate), and those that do not collapse but gradually compress with increasing load (porous polyethylene, polylactic acid). For similar-sized implants, the critical collapse point was earliest for the FCI3 HA implant, followed by the coralline HA, aluminum oxide, and polymethylmethacrylate implants. Smaller-sized collapsible implants showed earlier critical collapse points than larger-sized implants of similar material. CONCLUSIONS: A technique was established to assess the force required to disrupt the integrity of various orbital implants that is reliable, unbiased, and repeatable with any orbital implant. Orbital implants of different materials and sizes demonstrate different degrees of integrity. It is important to use similar-sized implants when comparing the integrity of different implant materials because size influences the force required to overcome the structural integrity of the implant.     

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.     

Micropulse laser trabeculoplasty under maximal tolerable glaucoma eyedrops: treatment effectiveness and impact of surgical expertise

AIM:To evaluate the effectiveness of micropulse laser trabeculoplasty(MLT)for eyes with open angle glaucoma(OAG)under maximal tolerable glaucoma eyedrops and to assess the effect of expertise performing MLT on its clinical effectiveness.METHODS:Medical records of 42 consecutive eyes of 34 patients diagnosed with OAG who underwent MLT were retrospectively reviewed.The effectiveness was determined using the Kaplan-Meier survival analysis.Failure was defined as an intraocular pressure(IOP)reduction of<20%from baseline,an IOP>21 mm Hg during two consecutive follow-up visits,or surgical intervention for OAG.To determine the impact of MLT surgical expertise on clinical effectiveness,the eyes were divided into two groups according to whether the procedure was conducted by an experienced specialist(defined as a glaucoma specialist who had conducted at least ten MLT procedures)or a less experienced glaucoma specialist.The difference in expertise was determined using a log-rank test.RESULTS:MLT was conducted by three glaucoma specialists.The overall survival rates were 0.76,0.48,and 0.44 at 1,3,and 6 mo,respectively.The survival rates for MLT performed by a less experienced glaucoma specialist were 0.62,0.31,and 0.25(n=21 eyes)at 1,3,and 6 mo,respectively,whereas the survival rates for MLT performed by an experienced glaucoma specialist were 0.90,0.64,and 0.64(n=21 eyes)at 1,3,and 6 mo,respectively.The log-rank test showed a significant difference in the survival curves of the two groups(P=0.0061).CONCLUSION:The 6-month effectiveness of MLT for controlling IOP is relatively limited in eyes with OAG using maximal tolerable glaucoma eyedrops.However,its effectiveness may be improved if performed by a glaucoma specialist with sufficient MLT experience.     

眶内植入带线羟基磷灰石义眼座的临床分析

目的 探讨眶内植入带线羟基磷灰石（HA）义眼座的临床效果。方法 对85例（85眼）眼球摘除者眶内植入带线HA义眼座。结果 术后随访12-36个月,平均18个月。义眼座活动度良好。82例结膜创口Ⅰ期愈合,2例结膜变薄,1例结膜创口裂开,义眼座暴露。无眶内血肿或感染等并发症。结论 眶内植入带线HA义眼座手术操作简单,术后并发症少,美容效果佳,临床效果好。     

Porous orbital implants, wraps, and PEG placement in the pediatric population after enucleation

PURPOSE: To investigate complications of various porous orbital implants and wrapping materials in the pediatric population after enucleation. DESIGN: A retrospective, comparative, nonrandomized study. METHODS: Between November 1992 and November 2006, patients younger than 15 years old were collected for study participation. They underwent enucleation with porous orbital implants primarily or secondarily at National Taiwan University Hospital. The authors used the hydroxyapatite (HA), Medpor, and Bioceramic orbital implant. The HA implant was wrapped with four different materials: donor sclera, Lyodura, porcine sclera, and Vicryl mesh. A part of HA implants and all bioceramic implants were wrapped with Vicryl mesh, added anteriorly with scleral patch grafts. All Medpor implants were unwrapped. RESULTS: Forty-seven cases had more than a two-year follow-up. The exposure rates according to implants and wraps were: donor sclera-wrapped HA (two of nine, 22%), porcine sclera-wrapped HA (three of three, 100%), Vicryl mesh-wrapped HA (one of five, 20%), and unwrapped Medpor (one of four, 25%). No exposure was found in four Lyodura-wrapped HA implants, and 22 Vicryl mesh-wrapped HA and Bioceramic implants with anteriorly scleral coating. The exposure rate was lower in cases with implants wrapped by our method and Lyodura than in those with implants wrapped by other materials (P < .001). Of 47 patients, 20 (42.5%) were fitted with peg-coupled prostheses and all had good prosthetic movements subjectively. CONCLUSIONS: Different types of implants and wraps resulted in various exposure rates in the pediatric population. The modified wrapping technique may prevent porous implants from exposure in children.     

A new titanium peg system for hydroxyapatite orbital implants

PURPOSE: To evaluate a new hydroxyapatite-coated titanium sleeve and titanium peg system for HA orbital implants. METHODS: The authors followed 54 patients receiving an HA-coated titanium sleeve and peg system and analyzed the complications associated with this peg system. The following data were recorded: type of surgery performed, size of implant used, type of HA used, time of pegging, follow-up duration, problems encountered, and treatment. RESULTS: Fifty-seven patients received the HA-coated titanium peg and sleeve system. The average duration of follow-up was 15 months (range, 3-30 months). Three patients were lost to follow-up after 1 month. Complications associated with peg placement in 54 patients included: discharge (9.2%), pyogenic granulomas (14.8%), peg falling out during prosthesis removal (9.2%), poor transfer of movement (1.8%), clicking (3.7%), conjunctiva overgrowing peg (1.8%), part of sleeve shaft visible (9.2%), peg drilled on an angle (1.8%), HA visible around peg hole (3.7%), and loose sleeve (3.7%). CONCLUSION: The HA-coated titanium sleeve and titanium peg is a new peg system available for HA orbital implants. Many of the complications associated with this peg system are similar to the commonly used polycarbonate peg system. Pyogenic granulomas and discharge, however, appear to be less frequently encountered with this new system. The HA-coated titanium sleeve and titanium pegs were well tolerated and appeared quieter in the socket than most polycarbonate pegs.     

义眼台植入术后脓性肉芽肿形成原因的探讨

目的探讨珊瑚多孔羟基磷灰石义眼台植入术后脓性肉芽肿形成的原因。方法回顾性分析我院羟基磷灰石义眼台植入250例,及外院手术者1例,共251例(251眼),对其中发生脓性肉芽肿的病例、分析其发生的原因。随诊4月~9年。结果251例中发生脓性肉芽肿4例(包括外院1例),其中1例脓性肉芽肿形成时,义眼台尚未钻孔,3例在钻孔及栓钉置入术4~7年后脓性肉芽肿形成。4例保守治疗效果欠佳,3例最终行义眼台取出术,1例拒绝手术。结论脓性肉芽肿形成是羟基磷灰石义眼台眶内植入较少见的并发症,发生原因与义眼台暴露,义眼台血管纤维化不足,义眼台钻孔及栓钉置入等有关。脓性肉芽肿的形成预示义眼台发生了感染,致病菌以厌氧性革兰氏染色阳性球菌为主。义眼台取出术是治疗的关键。     

Hydroxyapatite orbital implant vascularization assessed by magnetic resonance imaging

PURPOSE: To report hydroxyapatite (HA) implant enhancement patterns on magnetic resonance (MR) images at varying time intervals after implantation. METHODS: We retrospectively reviewed the records of 45 consecutive patients(from one author's practice) who underwent an MR imaging study 2 to 157 months after HA orbital implant placement. Implant fibrovascular ingrowth was assessed by analyzing the extent of implant enhancement seen on MR imaging.RESULTS Of 21 patients undergoing gadolinium-DTPA T1-weighted MR imaging 2 to 7 weeks after HA placement, 15 had enhancement limited to the implant rim (Grade I or less). Five patients had peripheral foci of enhancement (Grade II), and one patient had foci of enhancement extending to the center of the implant (Grade III). MR images obtained 9 to 15 weeks after HA insertion in all 14 patients had some degree of central enhancement (Grade III) and 11 had homogeneous enhancement throughout the implant (Grade IV or V). Seven patients in the homogeneous group were believed to have particularly intense enhancement patterns (Grade V). Of the 10 patients undergoing MR imaging from 31 to 69 weeks after surgery, 5 had Grade III enhancement and 5 had Grade IV enhancement. CONCLUSIONS: This study demonstrated consistent central HA orbital implant enhancement on MR imaging in the 9- to 15-week group and the >31-week postoperative group. HA orbital implant drilling and peg placement should be performed after central vascularization of the spherical implant has occurred. The results of this study support the principle of performing orbital implant drilling and peg placement at least 5 to 6 months after HA implant insertion.     

Prevention of exposure of porous orbital implants following enucleation

PURPOSE: To investigate effectiveness of adding a scleral patch graft on a Vicryl mesh-wrapped porous orbital implant to prevent exposure following enucleation. DESIGN: A retrospective, comparative, nonrandomized study. METHODS: From October 1996 to February 2006, 74 consecutive patients (74 sockets) who received porous orbital implants primarily or secondarily after enucleation at National Taiwan University Hospital (72 cases) and at Far Eastern Memorial Hospital (2 cases) were collected. Patient demographics, ocular diagnosis, the surgical technique, prior ophthalmic surgery, type, covering, and size of the implant, follow-up periods, and complications associated with pegs and implants were recorded. Group 1 patients received a Vicryl mesh-wrapped implant without a scleral patch graft. Group 2 patients received anterior capping with a scleral patch on the Vicryl mesh-wrapped implant. RESULTS: Of 74 identified cases, 12 were excluded for insufficient follow-up. The 62 remaining cases had more than a two-year follow-up. There were two implant exposures (12%, two of 17) in group 1. Retroauricular myoperiosteal graft and scleral patch were used to repair exposed implants successfully. No exposure was noted in group 2 (n = 45). A significant between-group difference in exposure rate was found (P = .02). Early conjunctival dehiscence followed by spontaneous healing occurred in three group 2 patients. CONCLUSIONS: Scleral patch graft and Vicryl mesh can act as duplicate barriers between anterior surface of implants and overlying soft tissue. The modified wrapping technique prevents porous implants from exposure effectively.     

Prosthetic motility in pegged versus unpegged integrated porous orbital implants

PURPOSE: To objectively measure and compare prosthetic motility in pegged versus unpegged orbital implants and to determine subjective patient assessment of motility after the pegging procedure. METHODS: A prospective case series of 10 patients with integrated porous orbital implants, who had secondary motility peg placement procedure, were studied. Infrared oculography was used to quantitatively assess pegged and unpegged prosthetic eye motility in horizontal and vertical excursions. RESULTS: For horizontal excursions, prosthetic motility in unpegged implants retained an average of 49.6% of measured motility of the contralateral normal eye, which increased to 86.5% with peg placement (P<0.05). For vertical excursions, prosthetic motility in unpegged implants retained an average of 51.3% of measured motility of the contralateral normal eye, which increased to 54.3% with peg placement (P>0.3). Nine of 10 patients judged their motility as "significantly improved," and 1 patient gave a rating of "some improvement" after peg placement. Four of 10 patients had granulomas around the peg sites. CONCLUSIONS: Objective assessment of prosthetic motility shows a significant increase in horizontal gaze after motility peg placement.     

Aspergillus mycetoma in a secondary hydroxyapatite orbital implant: a case report and literature review.

OBJECTIVE: The authors describe the first case report of a fungal abscess within a hydroxyapatite orbital implant in a patient who had undergone straightforward secondary hydroxyapatite implant surgery. DESIGN: Case report and literature review. INTERVENTION: Four months postoperatively after pegging and 17 months after original implant placement, chronic discharge and socket irritation became evident. Recurrent pyogenic granulomas were a problem, but no obvious area of dehiscence was present over the implant. The peg and sleeve were removed 31 months after pegging (44 months after original placement of the implant). The pain and discharge did not resolve, and the entire hydroxyapatite orbital implant was removed 45 months after sleeve placement and 58 months after initial implant placement. The pain and discharge settled rapidly. MAIN OUTCOME MEASURES: Cultures and histopathology. RESULTS: Results of bacterial cultures were negative. Results of histopathologic examination of the implant disclosed intertrabecular spaces with multiple clusters of organisms consistent with Aspergillus. CONCLUSIONS: Persistent orbital discomfort, discharge, and pyogenic granulomas after hydroxyapatite implantation should cause concern regarding potential implant infection. The authors have now shown that this implant infection could be bacterial or fungal in nature. This is essentially a new form of orbital Aspergillus, that of a chronic infection limited to a hydroxyapatite implant.     

Hydroxyapatite implant wrapping materials: analysis of fibrovascular ingrowth in an animal model

PURPOSE: To compare the influence of seven currently available spherical orbital implant wraps on host fibrovascularization of a hydroxyapatite (HA) orbital implant. METHODS: Five groups of 3 (15 total) adult male New Zealand albino rabbits underwent enucleation with placement of a 12-mm HA implant wrapped in high-porosity expanded polytetrafluoroethylene (e-PTFE), processed bovine pericardium, or processed human pericardium, sclera, or fascia lata. Magnetic resonance imaging before and after the intravenous administration of gadolinium-diethylenetriamine pentaacetic acid (DTPA, 0.1 mol/kg) was performed immediately before exenteration. Five rabbits (one with each of the different implant wraps) were killed at 4, 8, and 12 weeks, and the operated socket was exenterated. Histopathologic sections of the implants were then compared with the results of our previous study using polyglactin 910 mesh and autologous sclera as HA orbital implant wraps. RESULTS: Complete fibrovascularization of all the implants occurred by 12 weeks; however, HA implants wrapped with sclera, polyglactin mesh, and e-PTFE appeared to undergo more rapid fibrovascularization than spheres wrapped with other materials. CONCLUSIONS: Although all of the implant wraps studied may be suitable substitutes for donor sclera, we prefer polyglactin mesh because it is readily available, inexpensive, and without risk of transmissible diseases.