The effect of enucleation on orbital growth in patients with retinoblastoma

Orbital Development in Children with Retinoblastoma: An Imaging-Based Study

PURPOSE

To examine whether children treated for Retinoblastoma (Rb) have impaired orbital development.

METHODS

A retrospective case series was performed among children with Rb treated at a single medical center from 2004 to 2020. Orbital volumes and measurements were assessed by 3-dimensional image processing software. The main outcome measures were differences in orbital growth between Rb and non-Rb eyes assessed at last follow-up.

RESULTS

Among 44 patients included (mean age 16.09 ± 18.01 months), a positive correlation between age and orbital volume was observed only in the uninvolved, healthy eyes (p = .03). In unilateral cases, orbital growth in the horizontal, vertical, and depth planes was smaller on the affected side compared to the healthy eyes (p < .05). Orbits that underwent enucleation showed decreased growth over time compared to those treated conservatively (p = .017).

CONCLUSIONS

Orbital growth rate is slower in the orbits of children treated for Rb compared to healthy orbits. Enucleation negatively affects orbital growth.

Longitudinal Comparison of Orbital Volumes from Enucleated Eyes with Hydroxyapatite Orbital Implant in Unilateral Retinoblastoma Patients

PURPOSE

To compare the orbital volume between enucleated and contralateral, uninvolved orbits over a 5-year period in patients with unilateral retinoblastoma who underwent enucleation with hydroxyapatite (HA) implant placement by a single surgeon.

METHODS

A retrospective review was performed on the clinical records and radiographic images of unilateral retinoblastoma patients who underwent enucleation with primary HA implantation from 2003 to 2020 at a single institution. Bilateral orbital volume measurements were taken from the initial postoperative MRI scan and again at 1- and 5-years postenucleation. The main outcome measure was the longitudinal change in volume difference (∆𝑉). The implant size, age at enucleation, and sex were also evaluated. A linear mixed-effect model was used for analysis.

RESULTS

A total of 124 patients (73 males) with HA implants following enucleation were included. Overall, the unaffected orbit trended toward having a greater volume compared with the enucleated orbit, but this was not statistically significant (β = 0.003; p = 0.122). The mean age at enucleation was 2.4 years. The median time between enucleation and the initial, 1-year, and 5-year postoperative MRIs was 6 months, 17 months, and 55 months, respectively. There was no statistical correlation between age at enucleation, gender, implant size, or orbital volume at any time points ( p > 0.05).

CONCLUSIONS

Patients treated with enucleation and primary HA implant placement for unilateral retinoblastoma did not display significant asymmetry in orbital volume on 5-year postenucleation MRIs, suggesting that HA implants promote orbital growth comparable to a nonenucleated orbit in the pediatric population.

Rehabilitation of pediatric retinoblastoma patients with ocular prostheses and their subsequent modifications: A 15-year retrospective study

PURPOSE

Enucleation is a common treatment modality performed for pediatric retinoblastoma patients, and the resultant defects are reconstructed using an ocular prosthesis. The prostheses are modified or replaced periodically, as the child develops due to orbital growth and patient-error. The purpose of this report is to evaluate the replacement frequency of prostheses in the pediatric oncologic population.

METHODS

A retrospective review was completed by the two senior research investigators, of patients that had ocular prostheses fabricated following enucleation of their retinoblastoma from 2005 to 2019 (n = 90). Data collected from the medical records of the patient included the pathology, date of surgery, date of prosthesis delivery, and the replacement schedule of the ocular prosthesis.

RESULTS

During the 15-year study period, 78 enucleated observations (ocular prosthesis fabricated) were included for analysis. The median age of the patients at the time of delivery of their first ocular prosthesis was calculated to be 2.6 years (range 0.3-18 years). The median time to the first modification of the prosthesis was calculated to be 6 months. The time to modification of the ocular prosthesis was further stratified by age.

CONCLUSION

Pediatric patients require modification of their ocular prostheses throughout their growth and development period. Ocular prostheses are reliable prostheses with predictable outcomes. This data is helpful to set an expectation among the patient, parent, and provider.

[Ocular prosthetics in children-Possibilities and challenges]

One of the greatest challenges for ocularists is prosthetic fitting in children, especially in children with congenital anomalies such as clinical anophthalmia or functionless (blind) microphthalmia. The most frequent reason for prosthetic fitting in children is a condition following enucleation for retinoblastoma, followed by trauma and congenital pathologies. The standard treatment after enucleation or evisceration begins intraoperatively with the selection of an suitable implant and the use of a conformer at the end of the operation to shape the prosthetic cavity. An initial prosthesis can be fitted 4 weeks postoperatively, with a final fitting taking place 3 months later. If iatrogenic scarring or scarring due to an infection of the prosthetic cavity occurs, the approach of the ocularist must be appropriately adapted with the use of modified prosthesis shapes and shorter treatment intervals. Surgical options include scar excision and oral mucosa or amniotic membrane transplantation. Congenital anomalies require the shortest treatment intervals and even more so for anophthalmia than for microphthalmia. The strategy is characterized by simultaneous stimulation of the soft tissue of the ocular adnexa as well as the bony orbit. As self-inflating hydrogel expanders are no longer available, conservative prosthetic treatment is the only option. Close cooperation between child/parent, ocularist and ophthalmic plastic surgeon is the best prerequisite for a good long-term treatment outcome.

Outcomes of enucleation and porous polyethylene orbital implant insertion in patients with paediatric retinoblastoma: a long-term follow-up study

BACKGROUND/AIMS

To report the long-term outcomes of enucleation and insertion of porous polyethylene (PP) orbital implant according to the evolving surgical techniques and implant in patients with paediatric retinoblastoma .

METHODS

Patients with paediatric retinoblastoma who underwent enucleation and PP implant insertion from December 1998 to December 2014 were retrospectively reviewed and divided into four groups: group A, classic enucleation +PP implant; group B, enucleation +PP implant +anterior closure of the posterior Tenon's (ACPT) capsule; group C, enucleation +PP implant +free orbital fat graft +ACPT and group D, enucleation +smooth surface tunnel PP implant +ACPT. Survival analysis of implant exposure and eyelid malpositions was performed.

RESULTS

One hundred and ninety-eight eyes of 196 patients were included. The median follow-up period was 13.0 years (range, 5.0-21.1). A 20 mm implant was inserted for 149 eyes (75.3%). The 10-year exposure-free survival probabilities were 44.6% in group A, 96.4% in group B, 97.4% in group C and 97.7% in group D. ACPT was associated with significant reduction in implant exposure (p<0.001). The most common eyelid malposition was upper eyelid ptosis (24.2%). The eyelid malposition-free survival probability did not differ among the four groups. However, the insertion of a 20 mm implant was associated with significant reduction in upper eyelid ptosis and lower eyelid entropion (p=0.004 and 0.038, respectively).

CONCLUSIONS

The long-term postenucleation implant exposure was rare after PP implant insertion and ACPT, even with a 20 mm-diameter implant. A larger implant can be beneficial in long-term prevention of eyelid malposition.

Anophthalmic Sockets in Retinoblastoma: A Single Center Experience

PURPOSE

To evaluate outcomes of anophthalmic sockets in retinoblastoma at a tertiary care center in Singapore.

DESIGN

A retrospective study.

METHODS

Patients who underwent enucleation as sole/part of treatment for retinoblastoma were reviewed at our center from 2005-2017. Details including demographics, grouping and staging, adjuvant therapy, surgery, implant, and complications were collected.

RESULTS

Of 42 patients with retinoblastoma managed over the period, the anophthalmic sockets of 31 patients who underwent enucleation were analyzed. Mean age at enucleation was 2 years. Twenty-three enucleations were performed at our institution and 8 enucleations had been performed elsewhere. Seventeen patients (52%) had porous polypropylene, 9 patients (27%) had polymethylmethacrylate, 1 patient (3%) had glass implant, and 3 (9%) had dermis fat graft. The sizes of implants varied from 10 to 20 mm. Twelve patients had attempts at globe salvation before enucleation. Out of 28 patients with primary orbital implants, 3 had implant exposure. The rates of repeat surgery among patients with and without primary implant were 66.67% (2 out of 3) and 10.7% (3 out of 28), respectively. One patient had postenucleation socket syndrome with stock eye. Five patients referred for enucleation were conservatively managed.

CONCLUSIONS

Anophthalmic sockets in retinoblastoma have long-term implications if the primary procedure is not performed well. While the majority had good outcomes (structural and esthetic), a minority had complications requiring intervention. Ophthalmologists managing retinoblastoma must be aware of these. Primary implant had favorable outcome with minimal complications.