Complications in motility PEG placement for hydroxyapatite orbital implant in anophthalmic socket

Complications of Hydroxyapatite Pegging: Comparison between Polycarbonate and Titanium Peg System

PURPOSE

Polycarbonate peg has been customarily used for pegging of hydroxyapatite for years. For better movement, tissue tolerance, and to decrease the complications of pegging, titanium peg system has been used. This study compares the two systems.

METHODS

Complications associated with pegging (polycarbonate: Bio-Eye or titanium: Dr-Perry new P-K) were retrospectively reviewed from the charts of 153 patients admitted to the Labbafinejad Medical Center, Tehran, Iran, for over 5 years from 1997 to 2003.

RESULTS

A total of 153 cases were studied. Ninety-six (62.3%) were male and 57 (37.7%) were female, and the mean age was 27.7 years (6-59 years). In 88 cases pegs were poly-carbonate and sleeve system and in 65 cases pegs were titanium. Forty-one (46%) of cases with polycarbonate and 18 (27%) of cases with titanium had at least one or more complications (p=0.018). The most common complications were granulation tissue, discharge, overgrowth of conjunctiva, and peg falling out in 25%, 23%, 13%, and 8% in polycarbonate peg and 15%, 5%, 1.5%, and 0% in titanium peg group. The prevalence of the last three complications was statistically lower in titanium peg compared with polycarbonate. Twenty-five cases (35%) with polycarbonate peg and 5 cases (7.5%) with titanium peg had two or more complications (p=0.03). Peg removal was done in 11 cases of polycarbonate but only two cases of titanium peg in order to treat the complication.

CONCLUSIONS

Both pegging systems had some complications, although these were less severe and prevalent in titanium peg. More studies on complications due to titanium pegs are recommended.

Combined use of bulbar conjunctival pedicle flap and labial mucous membrane graft for porous orbital implant exposure: Long-term outcome

Implant exposure is the most common serious complication of porous orbital implants, and often requires surgical repair. This study aims to describe a new repair technique using a bulbar conjunctival pedicle flap and a labial mucous membrane patch graft, as well as to report its long-term results. A retrospective chart review was performed on all patients whose porous orbital implant exposures were repaired using this technique from 1995 to 2014. Twenty-three patients were included. The maximal defect dimension ranged from 2 to 18 mm. Sixteen patients (70%) also received a banked human scleral patch graft during their repair. The mean follow-up was 130 months (range 29-267 months). Eighteen patients (78%) were successfully treated with one repair surgery. At the final follow-up, 21 patients (91%) could comfortably wear a prosthetic eye, and 18 patients (78%) reported satisfactory cosmesis. Two patients (9%) developed small conjunctival cysts that were successfully excised. The combination of a bulbar conjunctival pedicle flap and a labial mucous membrane patch graft is a simple but effective technique in salvaging exposed porous orbital implants. Its long-term results are promising.

Integrated versus non-integrated orbital implants for treating anophthalmic sockets

BACKGROUND

Anophthalmia is the absence of one or both eyes, and it can be congenital (i.e. a birth defect) or acquired later in life. There are two main types of orbital implant: integrated, whereby the implant receives a blood supply from the body that allows for the integration of the prosthesis within the tissue; and non-integrated, where the implant remains separate. Despite the remarkable progress in anophthalmic socket reconstruction and in the development of various types of implants, there are still uncertainties about the real roles of integrated (hydroxyapatite (HA), porous polyethylene (PP), composites) and non-integrated (polymethylmethacrylate (PMMA)/acrylic and silicone) orbital implants in anophthalmic socket treatment.

OBJECTIVES

To assess the effects of integrated versus non-integrated orbital implants for treating anophthalmic sockets.

SEARCH METHODS

We searched CENTRAL (which contains the Cochrane Eyes and Vision Trials Register) (2016, Issue 7), Ovid MEDLINE, Ovid MEDLINE In-Process and Other Non-Indexed Citations, Ovid MEDLINE Daily, Ovid OLDMEDLINE (January 1946 to August 2016), Embase (January 1980 to August 2016), Latin American and Caribbean Health Sciences Literature Database (LILACS) (1982 to August 2016), the ISRCTN registry (www.isrctn.com/editAdvancedSearch), ClinicalTrials.gov (www.clinicaltrials.gov), and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (www.who.int/ictrp/search/en). We did not use any date or language restrictions in the electronic searches for trials. We last searched the electronic databases on 8 August 2016.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs of integrated and non-integrated orbital implants for treating anophthalmic sockets.

DATA COLLECTION AND ANALYSIS

Two authors independently selected relevant trials, assessed methodological quality and extracted data.

MAIN RESULTS

We included three studies with a total of 284 participants (250 included in analysis). The studies were conducted in India, Iran and the Netherlands. The three studies were clinically heterogenous, comparing different materials and using different surgical techniques. None of the included studies used a peg (i.e. a fixing pin used to connect the implant to the prosthesis). In general the trials were poorly reported, and we judged them to be at unclear risk of bias.One trial compared HA using traditional enucleation versus alloplastic implantation using evisceration (N = 100). This trial was probably not masked. The second trial compared PP with scleral cap enucleation versus PMMA with either myoconjunctival or traditional enucleation (N = 150). Although participants were not masked, outcome assessors were. The last trial compared HA and acrylic using the enucleation technique (N = 34) but did not report comparative effectiveness data.In the trial comparing HA versus alloplastic implantation, there was no evidence of any difference between the two groups with respect to the proportion of successful procedures at one year (risk ratio (RR) 1.02, 95% confidence interval (CI) 0.95 to 1.09, N = 100, low-certainty evidence). People receiving HA had slightly worse horizontal implant mobility compared to the alloplastic group (mean difference (MD) -3.35 mm, 95% CI -4.08 to -2.62, very low-certainty evidence) and slightly worse vertical implant motility (MD -2.76 mm, 95% CI -3.45 to -2.07, very low-certainty evidence). As different techniques were used - enucleation versus evisceration - it is not clear whether these differences in implant motility can be attributed solely to the type of material. Investigators did not report adverse events.In the trial comparing PP versus PMMA, there was no evidence of any difference between the two groups with respect to the proportion of successful procedures at one year (RR 0.92, 95% CI 0.84 to 1.01, N = 150, low-certainty evidence). There was very low-certainty evidence of a difference in horizontal implant motility depending on whether PP was compared to PMMA with traditional enucleation (MD 1.96 mm, 95% CI 1.01 to 2.91) or PMMA with myoconjunctival enucleation (-0.57 mm, 95% CI -1.63 to 0.49). Similarly, for vertical implant motility, there was very low-certainty evidence of a difference in the comparison of PP to PMMA traditional (MD 3.12 mm 95% CI 2.36 to 3.88) but no evidence of a difference when comparing PP to PMMA myoconjunctival (MD -0.20 mm 95% CI -1.28 to 0.88). Four people in the PP group (total N = 50) experienced adverse events (i.e. exposures) compared to 6/100 in the PMMA groups (RR 17.82, 95% CI 0.98 to 324.67, N = 150, very low-certainty evidence).None of the studies reported socket sphere size, cosmetic effect or quality of life measures.

AUTHORS' CONCLUSIONS

Current very low-certainty evidence from three small published randomised controlled trials did not provide sufficient evidence to assess the effect of integrated and non-integrated material orbital implants for treating anophthalmic sockets. This review underlines the need to conduct further well-designed trials in this field.

Current indications for pegging in the anophthalmic socket: are there any?

PURPOSE OF REVIEW

To highlight the development, problems, and current status of coupling porous orbital implants to the overlying prosthetic eye.

RECENT FINDINGS

Although increasing the risk of complications, pegging significantly contributes to prosthesis motility and satisfies the cosmetic expectations of some patients. Patients should be counseled regarding the increased risks in approximately one-third of individuals and that complications can occur even 10 years following implantation.

SUMMARY

Although implant peg placement has declined dramatically over the past decade, a precise and meticulous technique under intravenous anesthesia in the appropriately selected patient can be a successful outpatient procedure. Fortunately, most problems are of a minor nature, and over 85% of patients are able to retain their pegs following proper management and timely intervention. Additional visits to the ophthalmic plastic surgeon or ocularist are required that may not be necessary if a peg had not been placed.

Comparison of orbital prosthesis motility following enucleation or evisceration with sclerotomy with or without a motility coupling post in dogs

OBJECTIVE

To evaluate motility of silicone orbital implants and corneoscleral prostheses, with and without use of a motility coupling post (MCP) in dogs.

ANIMALS STUDIED

Eighteen mixed-breed dogs.

PROCEDURES

The motility of an orbital silicone implant and corneoscleral prosthesis after enucleation (n = 6), evisceration (n = 6), or use of a MCP with evisceration (n = 6) in dogs were compared. One eye from each dog had surgery whereas the opposite eye was used as a control. Clinical evaluations were performed three times a week. Histopathology of the orbital tissues was performed 8 and 12 weeks after surgery.

RESULTS

Implant motility in dogs with evisceration (vertical movement [VM] 8.04 +/- 2.13; horizontal movement [HM] 11 +/- 3.05) and evisceration with MCP (VM 9.61 +/- 1.59); HM was significantly greater than the enucleation group (VM 0.51 +/- 0.5; HM 1.22 +/- 0.68) (P < 0.01). Prosthetic motility in dogs with evisceration with MCP was significantly greater than in dogs with evisceration; dogs with evisceration had significantly greater motility than dogs with enucleation (P < 0.01). No postoperative complications were observed in any of the groups. No significant abnormalities were noted on histopathology.

CONCLUSIONS

MCP placement in silicone orbital implants significantly enhanced the prosthetic motility in dogs. This study supports the use of MCP in silicone orbital implants to enhance corneoscleral prosthesis motility and cosmetics in dogs.

Late exposure of the bioceramic orbital implant

PURPOSE

To investigate the long-term outcome of the Bioceramic orbital implant.

DESIGN

A retrospective, comparative, nonrandomized study.

METHODS

Data were collected from the patients receiving Bioceramic orbital implants at National Taiwan University Hospital between June 1, 2001 and November 1, 2005. The implant was wrapped with Vicryl mesh, adding anteriorly with a scleral patch graft following enucleation with primary or secondary implantation. The unwrapped implant was inserted into an eviscerated globe with posterior sclerotomy and cornea preserved. Primary or secondary placement of sleeve was performed in some patients.

RESULTS

A total of 112 cases were reviewed. Four patients were excluded attributable to insufficient follow-up. The other 108 patients had a mean follow-up period of 35.8 +/- 10.6 months (range, 24 to 70 months). Fifty patients (46.3%) received the pegging procedure. Eight of 108 (7.4%) cases of late exposure were identified on average 20.7 months after implantation. We identified no cases of implant exposure in 30 cases of enucleation and eight cases of secondary implant when the implant was wrapped in Vicryl mesh and an anterior scleral cap was used. All exposures developed in eviscerated patients (70 cases): two without pegging, three with primary placement, and three with secondary placement of the sleeve. The exposure rate was higher in patients with eviscerated globes, pegged implants, and prior ocular operations (P < .005).

CONCLUSIONS

Late exposures of Bioceramic implants were found after long-term follow-up, associated with evisceration, pegging, and prior ocular surgeries. The modified wrapping technique can prevent exposure following secondary implantation and enucleation.

Exposure Rate of Hydroxyapatite Orbital Implants

OBJECTIVE

To document the long-term experience with hydroxyapatite (HA) orbital implants (Bio-Eye) and analyze the factors influencing implant exposure, including surgical type, procedural modification, use of different wrapping materials and peg materials.

DESIGN

Retrospective observational case series.

PARTICIPANTS

Eight hundred two eyes from 802 patients who underwent anophthalmic socket surgery (eviscerations, enucleations, secondary implant placements) using HA implants, performed by one surgeon between May 1990 and December 2005.

METHODS

All patients' clinical records were reviewed. Baseline age, cause of anophthalmic surgery, surgical type, size of HA implant, wrapping material, and peg system were recorded.

MAIN OUTCOME MEASURES

Postoperative complications, especially implant exposure, were recorded separately before and after pegging, and compared according to type of surgery, wrapping material, and peg system.

RESULTS

The main cause of anophthalmic surgery was trauma (73%). A variety of wrapping materials have been used, including Tutoplast-dura, Vicryl mesh, autogenous sclera, and polyester-urethane. Implant exposure occurred in 17 patients (2.1%) before pegging and 14 (4.0%) after pegging. The exposure rate was significantly higher in eyes eviscerated without (7.2%) than with (1.1%) keratectomy (P = 0.018), but did not differ according to type of surgery (P = 0.710). When distributed according to 5-year periods, the exposure rate was higher from 1990 to 1994 (4.7%) than in later periods (P = 0.004). In patients who underwent enucleation or secondary implantation, there was no difference in exposure rate between Tutoplast-dura- and Vicryl mesh-wrapped implants (P = 0.235). Among the 353 patients (44.0%) who underwent pegging, those who received titanium-pegged implants had a significantly lower incidence of peg extrusion (5.2%), major discharge (5.2%), and pyogenic granuloma (9.1%) than those with nonsleeved polymethyl methacrylate and sleeved polycarbonate peg materials (P<0.05).

CONCLUSIONS

Exposures associated with HA orbital implants decreased with the improvement of surgical technique over time and have been managed successfully, both before and after pegging. The incidence of peg-related complications have decreased since the introduction of the titanium peg system.

Complications of orbital implants: a review of 542 patients who have undergone orbital implantation and 275 subsequent PEG placements

PURPOSE

To inform patients and physicians of the complications associated with three commonly used orbital implants, as well as associated anophthalmic socket issues.

METHODS

A retrospective chart review of 542 patients who underwent eviscerations, enucleations and secondary procedures by one surgeon (Dr. James Oestreicher) was completed, paying special attention to complications in the follow-up period prior to pegging, as well as those that occurred post-pegging.

RESULTS

Approximately 60% of patients experienced complications prior to implant drilling, with discharge being the most prevalent (15.9%). Secondary procedures were associated with significantly greater complication rates prior to implant drilling. Silicone implants had significantly less pre-pegging pyogenic granuloma (P = 0.011) and hypo-ophthalmos (P = 0.042) than the other implant types. Seven implants had to be removed due to exposure. Implant drilling and peg placement were performed in 275 patients. Implant drilling complications were experienced by 67.4% of pegged patients, with a change in discharge from prior to pegging (27.2%) being the most prevalent. Plastic peg systems had a significantly higher incidence of complications than titanium systems.

CONCLUSIONS

The majority of orbital implantations involve complications, these being largely minor ones which resolve spontaneously or are easily treated. Secondary implant procedures involve a higher likelihood of complications. Silicone implants have the smallest amount of complications. Should patients decide to undergo pegging, evidence sides strongly for the use of a titanium peg and sleeve system over the other peg types. Implant removal is a rare event; occurring in 1.3% (n = 7) of the study population.

Perspective on Orbital Enucleation Implants

The philosophy and design of orbital enucleation implants have evolved significantly over the past 50 years. Animal studies and improved imaging techniques have changed our understanding about the physiology and anatomy of the post-enucleation orbit. Changes in implant design and biomaterials have reduced complication rates. It is our impression that for many ophthalmic professionals in training, the rational behind the current thinking in implant design and biomaterials is unclear. This is in part related to the older literature on orbital enucleation implants, which is scattered and at times contradictory. This review aims to present the historical information in a coherent and concise form; provide evidence based review of changes in the practice patterns of enucleation; identify areas of continuing controversy; and highlight gaps in the scientific literature about orbital implants, in particular, the poor understanding of implant and prosthesis motility.

Complications of primary placement of motility post in porous polyethylene implants during enucleation

PURPOSE

To evaluate the complications associated with the primary placement of a motility coupling post (MCP) in spherical porous polyethylene (PP) implants at the time of enucleation.

DESIGN

Retrospective, interventional case series.

METHODS

The records of all patients who had undergone primary enucleation and spherical PP implant with MCP insertion, and who were followed for at least six months were reviewed. The MCP was screwed to a wrapped implant to protrude 3 mm to 4 mm anteriorly. After placing the implant into the orbit, the extraocular muscles were sutured to the implant, and the Tenon capsule and conjunctiva were closed onto the MCP. When the MCP was not exposed spontaneously within two months after surgery, it was externalized with a conjunctival cut-down procedure.

RESULTS

The study included 52 patients (29 male, 23 female; age range, three to 76 years). The MCP became exposed spontaneously in 10 patients (19%). In the early postoperative period, we recorded nine complications in seven patients (13%), which might be related to primary MCP placement. These included prominent MCP decentration associated with implant motility restriction (6%), preseptal cellulitis (4%), and conjunctival prolapsus (8%). An ocular prosthesis was fit successfully onto the MCP in 51 patients. During the late period, 22 complications occurred in 15 patients (29%), including excessive discharge (15%), MCP decentration (4%), implant exposure (6%), implant infection (2%), pyogenic granuloma (8%), conjunctival overgrowth over the MCP (2%), conjunctival discoloration (4%), and lax eyelid syndrome (2%). Mean follow-up time was 34 months (range, six to 68 months).

CONCLUSIONS

Although MCP placement in the spherical PP implant during enucleation is a useful technique, it may be associated with complications such as MCP decentration, excessive discharge, exposure, and infection of the implant.

Porous Implant Exposure: Incidence, Management, and Morbidity

PURPOSE

To identify what factors may predispose patients to exposure of porous anophthalmic implants and to determine the outcome of exposed porous implants.

METHODS

Examination of pooled data obtained through a PubMed literature search of English-language publications from 1989 through 2004 using the key words enucleation, evisceration, and socket reconstruction.

RESULTS

Porous implants were inserted in 80% (3012 of 3777) of the cases identified from 49 publications. The difference in exposure rate between coralline hydroxyapatite (4.9%) and porous polyethylene (8.1%) implants is primarily related to a higher reported complication rate of uncovered porous polyethylene implants, particularly in retinoblastoma patients. Other techniques associated with increased exposures include wrapping implants with bovine pericardium or polyglactin mesh. Evisceration and secondary procedures did not have statistically different complication rates compared with enucleation. There are more late exposures of porous polyethylene than coralline hydroxyapatite implants. Spontaneous healing of exposures occurred in 13% (19 of 145) of cases. Covering exposures with patch grafts underneath vascularized conjunctival flaps was the most successful method of surgical repair. Implant removal was necessary after 29% (42 of 145) of exposures.

CONCLUSIONS

Although the published literature between 1989 and 2004 reports higher complication rates for uncovered porous implants and implants wrapped with bovine pericardium or polyglactin mesh, pooling data from different studies may mask very good or poor results obtained by individual surgeons. Spontaneous healing of exposed porous implants is relatively uncommon. However, many exposed porous implants can be salvaged with secondary repair.

Late porous polyethylene implant exposure after motility coupling post placement

PURPOSE

To report the probable association of motility coupling post placement and late porous polyethylene implant exposure.

DESIGN

Retrospective, observational case series.

METHODS

This was a retrospective analysis of 27 patients who had primary porous polyethylene orbital implantation from February 1999 to November 2000. Data on demographics, previous surgery, ocular diagnosis, type of surgery, size of the implant, and motility coupling post placement were collected. Complications of porous polyethylene implants and implant exposure were documented.

RESULTS

Among the 27 patients, 18 eyes (66.7%) received motility coupling post insertion after primary porous polyethylene implantation. Implant exposure occurred in six (33.3%) of the 18 eyes with motility coupling post insertion. None of the eyes without insertion had implant exposure. The mean interval between porous polyethylene implantation and motility coupling post placement for the implant exposure group (6 of 18) was 6.5 +/- 0.4 months, which was not statistically significant compared with 7.2 +/- 0.6 months in the nonexposure group (12 of 18). For these 6 cases of implant exposure, the mean interval between implantation and implant exposure was 24.2 +/- 11.8 months, and the mean interval between pegging and exposure was 17.6 +/- 11.7 months. Among these 6 patients, 4 underwent removal of exposed porous polyethylene implants and reimplantation of hydroxyapatite implant or dermis fat reconstruction.

CONCLUSIONS

We found a trend (P =.07) of increasing risk of porous polyethylene implant exposure with motility coupling post placement. Although the pegging group did not show a statistically significant higher rate of exposure compared with the nonpegging group, we believe that more care was needed when performing motility coupling post placement. In addition, longer postoperative follow-up is needed after insertion of a motility coupling post.

Current Trends in Managing the Anophthalmic Socket After Primary Enucleation and Evisceration

PURPOSE

To evaluate current trends in the management of the anophthalmic socket after primary enucleation and evisceration.

METHODS

The active membership of the American Society of Ophthalmic Plastic and Reconstructive Surgery (ASOPRS) was surveyed regarding primary enucleations and eviscerations performed between January and December 2002. Survey questions included practice demographics, orbital implant use, wrapping materials, placement of a motility peg, reasons for implant choice, and complications encountered.

RESULTS

A total of 2,779 primary orbital implants were reported, comprising 1,919 (69.1%) enucleations and 860 (30.9%) eviscerations. The high-density porous polyethylene implant was used most frequently for enucleations (42.7%), followed by coralline hydroxyapatite (27.3%) and nonporous alloplastic implants (19.9%). For eviscerations, the high-density porous polyethylene implant was the most commonly used implant (42.3%), followed by hydroxyapatite (25.9%) and nonporous alloplastic implants (25.7%). The top 3 reasons for implant choice were outcome (69.3%), cost (43.6%), and experience (39.5%). Most implants were either not wrapped (59.8%) or were wrapped in donor sclera (25.2%) or polyglactin mesh (7.2%). Pegs were used in 8.1% of all implants reported. The most frequent complications encountered for unpegged implants were exposure (3.2%) and infection (0.4%). For pegged implants, the most common complications reported were pyogenic granuloma (13.7%), exposure (5.7%), and discharge (5.7%).

CONCLUSIONS

In managing the anophthalmic socket, ASOPRS survey respondents preferred to use the porous polyethylene implant after primary enucleation and evisceration. Most orbital implants were not wrapped, and most surgeons preferred not to place a motility post or peg in the implant.