Leukocoria from myelinated nerve fibers and retinoblastoma

Omar Warda; Stephanie Lemaitre; Rodrigo Anguita; Mandeep S Sagoo; M Ashwin Reddy

doi:10.4103/pajo.pajo_92_21

CASE REPORT

Year : 2021 | Volume : 3 | Issue : 1 | Page : 29

Leukocoria from myelinated nerve fibers and retinoblastoma

Omar Warda¹, Stephanie Lemaitre², Rodrigo Anguita², Mandeep S Sagoo³, M Ashwin Reddy⁴
¹ Retinoblastoma Unit, Royal London Hospital, London, UK
² Retinoblastoma Unit, Royal London Hospital; Department of Ophthalmology, Moorfields Eye Hospital, London, UK
³ Retinoblastoma Unit, Royal London Hospital; Department of Ophthalmology, Moorfields Eye Hospital; NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital, University College London Institute of Ophthalmology, London, UK
⁴ Retinoblastoma Unit, Royal London Hospital; NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital, University College London Institute of Ophthalmology, London, UK

Date of Submission	16-May-2021
Date of Acceptance	18-Jul-2021
Date of Web Publication	24-Aug-2021

Correspondence Address:
Dr. Omar Warda
Whitechapel Rd, London E1 1FR
UK

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/pajo.pajo_92_21

Abstract

We report the clinical findings and imaging in an 11-month-old male referred to the pediatric ocular oncology service for leukocoria. The diagnosis of concomitant myelinated nerve fibers and retinoblastoma group O/C was established. In this case, the association of these two conditions led to early diagnosis of retinoblastoma with successful treatment and good visual outcome.

Keywords: Leukocoria, ocular oncology, retinoblastoma

How to cite this article:
Warda O, Lemaitre S, Anguita R, Sagoo MS, Reddy M A. Leukocoria from myelinated nerve fibers and retinoblastoma. Pan Am J Ophthalmol 2021;3:29

How to cite this URL:
Warda O, Lemaitre S, Anguita R, Sagoo MS, Reddy M A. Leukocoria from myelinated nerve fibers and retinoblastoma. Pan Am J Ophthalmol [serial online] 2021 [cited 2023 Mar 28];3:29. Available from: https://www.thepajo.org/text.asp?2021/3/1/29/324524

Case Report

An 11-month-old white male was referred to the pediatric ocular oncology service for leukocoria which had been noted by the parents when the child looked nasally. A complete ocular evaluation was performed under anesthesia. During the first examination, intraocular pressures were normal at 10 mmHg in both eyes with sevoflurane induction. The anterior segments were unremarkable with a horizontal corneal diameter of 12 mm and a clear lens bilaterally. Indirect ophthalmoscopy with 360° scleral depression was performed on both eyes; the right eye was normal. A white retinal mass about 3 disc diameters in size was seen inferonasally located about 1 disc diameter inferior to the disc in the left eye. There was an area of subretinal fluid and some calcified vitreous seeds around the tumor. In addition, in the same eye, the optic disc looked anomalous and hyperemic with the presence of white, relatively sharply, demarcated feather-like structures located in the nerve fiber layer, in the juxtapapillary part of the posterior pole but sparing the foveal avascular zone. Although retinoblastoma infiltration was considered, this area was diagnosed as myelinated fibers of the optic nerve [Figure 1].

Figure 1: Fundus picture at presentation showing the nasal retinoblastoma associated with myelinated nerve fibers of the optic nerve

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The final diagnosis was group O/C retinoblastoma according to the International Intraocular Retinoblastoma Classification (IIRC) [Table 1] in the left eye with incidental myelinated nerve fiber layer or CT2a if using the AJCC 8th Edition (needs reference).^[1],[2]

Table 1: International Intraocular Retinoblastoma Classification system for Intraocular Retinoblastoma^[2]

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Treatment consisted of systemic intravenous chemotherapy (6 cycles of vincristine, etoposide, and carboplatin) to treat his left eye retinoblastoma, with an excellent tumor response [Figure 2]. Screening for the RB1 gene in the blood showed no pathogenic variants (nonheritable type) and the final visual outcome was 6/6 as the macula was healthy with no tumor involvement.

Figure 2: Fundus picture after treatment with intravenous chemotherapy, showing a completely calcified retinal mass and the unchanged myelinated nerve fibers

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Discussion

Retinoblastoma is the most common primary intraocular malignancy in children.^[3] It is frequently diagnosed with strabismus (generally caused by small tumors involving the macula) or leukocoria (generally observed for larger tumors).^[4],[5] Other causes of leukocoria include Coats' disease, persistence of fetal vasculature, or toxocariasis, but it is essential to rule out retinoblastoma because increased lag time may affect the risk of mortality.^[6]

Myelinated retinal nerve fiber layer is a rare benign condition with an incidence of 1% in the general population which is usually asymptomatic and only detected as an incidental finding in most cases, but it has been reported to rarely present with an abnormal red reflex (leukocoria).^[7] Pathogenesis of myelinated retinal nerve fiber layer is not fully understood, but it could be related to abnormal migration of oligodendrocytes, which results in abnormal myelination of nerve fibers in the retina.^[8] This condition is therefore completely unrelated to retinoblastoma, but the incidental finding of these two causes of leukocoria in the same eye helped the early diagnosis and treatment of retinoblastoma, with an excellent visual outcome of 20/20.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient (s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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