A palliative approach for rehabilitation of a pediatric patient with retinoblastoma.

Retinoblastoma is a highly malignant neoplasm. Most of the cases are usually far advanced at the time of detection, requiring enucleation to salvage the child's life. However, the cosmetic rehabilitation of these patients should always be an integral part of their treatment, which helps in their re-integration in the society. This paper presents a case of 5-year-old patient who had undergone enucleation of her left eye due to retinoblastoma. A multidisciplinary approach, including ophthalmologist, psychotherapist, and a prosthodontist, was adopted to meet her physical, psychological, functional, emotional, social, and cosmetic demands. The patient was rehabilitated cosmetically with precisely fabricated ocular prosthesis. An ocular prosthesis is a highly positive and non-invasive approach to improve the cosmetic appearance and psychological well-being of patient.

INTRODUCTION

Retinoblastoma is a highly malignant tumor of the eye that grows relentlessly and almost always has a fatal outcome if untreated. It is cosmopolitan and affects all races. Both sexes are affected equally, and the tumor has no predilection for the right or left eye. It has an incidence varying from 1 in 3300 to 1 in 20,000 live births,[1] and accounts for approximately 2.5-4% of all cancers diagnosed in children younger than 15 years.[2] Most tumors occur before the age of 2 years and are diagnosed upto the age of 5 years. Approximately, 40% of all retinoblastomas are bilateral and 60% are unilateral.

In the absence of a known family history of the disease, the early months of retinoblastoma growth in a child's eye usually go undetected by both the family and the primary care physician. Bilateral retinoblastoma is most often asymmetric and is usually diagnosed at an earlier age than the unilateral disease. The average age at diagnosis in bilateral disease is 12 months; in unilateral disease, it is 24 months. A white reflex, i.e., cat's-eye reflex or leukocoria in the pupil is the most common clinical sign (56%).[3] Transillumination, fluorescein angiography, ultrasonography, computed tomography, magnetic resonance imaging are routinely used in diagnosing retinoblastoma. Early diagnosis and prompt treatment are important factors in a child's survival and can often salvage useful vision in one or both eyes. However, unilateral retinoblastoma, unfortunately, is usually far advanced at the time of detection, and little normal retina is seen. In bilateral cases, the presentation is often strikingly asymmetric, with one eye involved by massive tumor and the opposite eye much less involved. In both of these situations, enucleation of the more advanced eye is the wisest choice.

The modalities currently used to treat intraocular retinoblastoma include enucleation, laser photocoagulation, laser hyperthermia, cryotherapy, radioactive plaque brachytherapy, external beam radiotherapy (EBR), and systemic chemotherapy.[4] The approach to treatment depends on the size and extent of tumors, the sites of involvement, and the patient's systemic involvement. Usually, several different modalities are necessary.

Several studies have shown that the most common cause of enucleation in pediatric population is retinoblastoma.[5] The psychological effect of losing an eye may present greater difficulties for the patient than the physical disability.[6] The patient loses an organ with an important sensory function and is also faced with a distortion of facial appearance. The associated psychological effect of these defects on the patient requires immediate management and rehabilitation intervention by a team of specialists. The pre-operative time spent addressing eye removal, as well as discussing life after losing an eye, will reap benefits in post-operative recovery and acceptance. Psychiatric referral is appropriate for patients who manifest increased difficulty coping with the loss.

Increasing interest in this field has resulted in a better understanding of the problems associated with surgical treatment of retinoblastoma and presently, a multidisciplinary approach is considered a most effective approach to rehabilitate rather than just treat the patient. Therefore, the combined efforts of the ophthalmologist, the plastic surgeon, psychologist, and the maxillofacial prosthodontist are essential to restore the patient's quality of life.[7] This paper presents a palliative approach to rehabilitate a 5-year-old girl with retinoblastoma, who has undergone enucleation of her left eye.

CASE REPORT

A 5-year-old female patient reported to the department of prosthodontics with the complaint of unaesthetic facial appearance due to absence of left eye [Figure 1]. Her parents gave history of retinoblastoma which was diagnosed at the age of 2 years, for which enucleation was done at 2.5 years of age. Patient also received chemotherapy and radiotherapy for treatment of her malignancy. At the age of 3 years, a stock artificial eye was placed in the patient's eye but, due to pain and irritation caused by artificial eye, patient used to remove the prosthesis and showed extreme resistance to wearing of the prosthesis.

Figure 1

Pre-operative photograph showing enucleated socket of left eye

Clinical procedure

Patient's past experience with prosthesis precluded the use of stock ocular prosthesis. After careful examination of the area of the defect and treatment planning, it was planned to fabricate a custom ocular prosthesis for the patient. The procedure, including its maintenance and limitations, was explained to the patient/guardian to gain their co-operation. Patient/guardian consent was taken for making photographic records.

The procedure was initiated by the first making the impression of the socket with a thin mix of ophthalmic alginate (Opthalmic moldite, Milton Roy Company, Sarasota, FL, USA), then making a two-piece dental stone (Kalabhai Karson Pvt. Ltd., Mumbai, India) cast from the impression by double pour technique [Figure 2]. The wax pattern was formed on the cast using carving wax mixed with sticky wax, and tried in the patient's eye and checked for accuracy in the terms of retention, proper extension in all directions, scleral contour and convexity and finally positioning the iris, matching in size and color of contralateral eye, obtained from stock eye. The final wax pattern with iris button was evaluated in the patient's socket and modified accordingly [Figure 3].

Figure 2

Impression of the ocular defect (a) and cast obtained (b)

Figure 3

Final wax pattern try-in

After making necessary modifications, the wax pattern was invested, flasked, and de-waxing was done [Figure 4]. The next step was to reproduce scleral shade of the normal eye. For this, shade tabs were prepared by mixing and matching different shades and proportions of tooth-colored acrylic (SC 10, Pyrax, Roorkee, India) till the color of sclera of the other eye was replicated. To simulate the veins of the normal eye, veins were separated from the veined heat-cured poly-methyl methacrylate (PMMA; Trevalon, Dentsply India Pvt. Ltd., Gurgaon, India) and they were incorporated in the dough of the determined acrylic shade, followed by routine curing, finishing, and polishing. Finally, a thin film of the sclera was removed and replaced by a clear film of transparent heat-cured PMMAe resin (Trevalon, Dentsply India Pvt. Ltd.) to simulate corneal translucency.

Figure 4

De-waxed mold

After processing, the properly finished and polished prosthesis was inserted in the socket [Figure 5] after being disinfected with 0.5% chlorhexidine and 70% isopropyl alcohol for 5 min and lubricated with an ophthalmic lubricant (Ecotears, Intas Pharmaceuticals Limited, Ahmedabad, India) to maintain a tear film over the prosthesis and to improve eye movements. Minor adjustments were made at the time of delivery as per the patient's comfort and esthetics. Instructions were given to the patient regarding proper care and handling of the prosthesis as well as the maintenance of socket hygiene and the need for regular recall appointments was emphasized. As in the early childhood, orbital volume increases in a linear fashion,[89] and a change of prosthesis is required between 18 and 26 months following prosthesis placement in children.[10] So, the patient was recalled every 6 months for follow-up.

Figure 5

Post-operative photograph showing prosthesis in lieu of enucleated eye

In the follow-up period of 6 months, the patient was able to wear a cosmetically acceptable ocular prosthesis without any discomfort. So, the patient was successfully rehabilitated by custom ocular prosthesis.

DISCUSSION

Cancer is always a frightening diagnosis, and when it affects children, the situation is overwhelming. Eye cancer in children, though rare, is the third leading cancer of childhood. Retinoblastoma can be a particularly distressing form of cancer as it is potentially fatal and can result in loss of one or both eyes. The shock of diagnosis often results in an overwhelming number of intense emotions. Depression, feelings of helplessness, hopelessness, and sadness can occur throughout the cycle of grieving and beyond.

Enucleation during infancy[11] or congenital anophthalmos or severe microphthalmos can lead to severely underdeveloped bony orbital growth, cosmetic deformity, and facial asymmetry. Placement of prosthesis has been proven to play a definite role in stimulating the orbital growth. The regular replacement or modification of prosthesis is important to give continuous stimulus for socket growth.[12]

The fundamental objective in restoring a congenital as well as acquired defect of eye with an ocular prosthesis is to enable the patient to cope better with the difficult process of rehabilitation after an enucleation or evisceration. A cosmetically acceptable prosthesis is that reproduces the color, form, and orientation of iris and allows the patient to return to accustomed lifestyle.

The literature has suggested many techniques for the fabrication of ocular prosthesis. Stock eye prosthesis was advocated by Laney.[13] They are available in standard sizes, shapes, and colors and require no special skills or materials for fabrication. They are relatively inexpensive and the entire process is also less time-consuming. However, in majority of cases of enucleation, custom ocular prosthesis is advantageous as there is improved adaptation to underlying tissues, increased mobility of the prosthesis, and excellent esthetics due to better match of the size and color of the iris and sclera.[14]

CONCLUSION

The repercussions of retinoblastoma, its treatment, and its outcome are felt throughout the life of the patient and his/her family, so providing the patient with a cosmetically pleasing custom ocular prosthesis is a palliative approach for rehabilitation of a pediatric patient with retinoblastoma. Custom eyes have several advantages including better mobility, even distribution of pressure due to equal movement, thereby reducing the incidence of ulceration, improved fit, comfort, and adaptation, improved facial contours, and enhanced esthetics gained from the control over the size of the iris, pupil, and color of the iris and sclera. Custom ocular prosthesis not only fulfills the esthetic and psychological demands but also stimulates bony orbital growth, thereby reaping long-term benefits of restoring facial symmetry and esthetics.