Eye enucleation

Retinoblastomas usually occur in children under three years of age as chalky-white retinal primary tumours that can be multifocal and bilateral with vitreous fluid and/or subretinal space spread.¹

Malignant melanomas are described as uveal (ocular) or conjunctival (extraocular). Uveal melanomas are likely to be pigmented and lobulated primary choroid or ciliary body tumours but can also arise in the iris. Choroid melanoma may appear as fungating tumours when extending into the subretinal space.¹ A range of specimens from biopsy, iridectomy, local resection, enucleation and exenteration can be received.^2-4

Carcinomas of the conjunctiva, eyelid and lacrimal gland as well as sarcomas and lymphomas also may be found in these specimens.

Extenteration is rare surgery for malignancies such as retinoblastoma and melanoma involving tissues adjacent to the orbit.²

• No
  • Non-routine fixation (not formalin), describe.

• Yes
  • Special studies required, describe.
  • Ensure samples are taken prior to fixation.

Record additional orientation or designation provided by operating clinician:

• Absent
• Present
  • Method of designation (e.g. suture, incision)
  • Featured denoted

Inspect the globe and identify laterality by observing the posterior surface. The ciliary vessels are located medially and the inferior oblique muscles are located laterally to the optic nerve.^1,2,8

• Long ciliary arteries are visible as a posterior blue line and lie on the horizontal plane ^2,8
• A thick muscular insertion is seen entering the posterotemporal side of the inferior oblique muscle; just below the horizontal plane and temporal long ciliary artery^2,8
• The superior oblique muscle inserts into the superotemporal pole of the globe ^2,8
• The cornea is longer horizontally than vertically^2,8
• The optic nerve is closer to the nasal than temporal limbus^2,8

Complete exenteration specimens can be orientated by the longer eyelashes and fold of the upper eyelid as well as the caruncle and punctae of the medial canthus.^3,8

Complete exenteration includes eyelids, optic nerve, extraocular muscles, orbital fat and periosteum as well as the globe.³

• Globe in three dimensions; antero-posterior x horizontal x vertical maximum dimensions²
• Optic nerve length and diameter²
• Cornea in two dimensions; horizontal x vertical²
• Pupil in two dimensions; horizontal x vertical²

• Total specimen in three dimensions; antero-posterior, horizontal and vertical maximum dimensions
• Components as for enucleation specimens
• Other tissues, describe and measure in three dimensions

Ensure adequate fixation prior to dissection in at least 60ml of formalin for 24-48 hours.^1-8 Intraocular damage will occur if the globe is opened (windows cut) or injected with formalin prior to fixation.⁸

Some procedures suggest transferring to 70% ethyl alcohol overnight before dissection. Another suggested technique is to process the specimen whole before undertaking detailed dissection.

Tumour

• Section the optic nerve transversely at the resection margin and submit for processing prior to opening the orbit to prevent potential contamination by neoplastic cells.¹
• Sample vortex veins.
• Usually sectioned in the anteroposterior plane; the plane of the first section is guided by external examination and transillumination. The purpose of this assessment is to ensure that one segment represents the maximum tumour dimension and its relationship with pupil and optic nerve. Section the globe in the antero-posterior plane at 3-4mm intervals according to findings of transillumination.

Non-tumour

• For cataracts and glaucoma; vertical sections as these surgical sites are present superiorly
• For macular pathology; horizontal sections

Ensure adequate fixation prior to dissection in at least 60ml of formalin for 48 hours.⁸ One method suggests placing gauze or tissue paper between the eyelids during fixation.⁸

After sufficient fixation, paint the external soft tissue surgical margins with ink to highlight the superior and inferior aspects⁸ and record the colours applied.

• If bone is included in the specimen, describe, dissect from soft tissue and submit for decalcification before processing.⁸
• Take the first section from the optic nerve margin⁸
• Then dissect off the inferior calotte
• Transversely section through the entire specimen (soft extraocular tissues and globe) at 3-4mm intervals in a similar manner to enucleation specimens (but also obtaining sections that demonstrate extent of extraocular spread).
• Aim to produce at least three thick sections. These will require deeper cassettes (>5mm) for processing.
• Radially section the medial and lateral slices to demonstrate any tumour close to these margins⁸

Compartments involved⁴

• Iris
• Ciliary body
• Choroid
• Extra-scleral invasion (mm)
• Growth pattern
• Focal solid
• Diffuse or ring

• Bulbar
• Palpebral
• Fornix
• Caruncle
• Plica seminlunaris
• Limbus
• Cornea

Distance of tumour to margins (mm)

• Distance of tumour to head of optic nerve
• Distance of tumour to pars plicata

Describe the following features of the tumour.

Vitreous seeding

• Absent
• Present

Tumour growth pattern

• Endophytic
• Exophytic

• Size
• Shape
• Colour
• Cataract
  • No
  • Yes

• Opacification
  • No
  • Yes
• Decentration
  • No
  • Yes
• Laser capsulotomy site
  • No
  • Yes

Retrieved from resection specimen

• Describe site(s)
• Number retrieved

Separately submitted

• For each specimen container, record specimen number and designation
• Collective size of tissue in three dimensions (mm)
• Number of grossly identified lymph nodes submitted
• Maximum diameter of each (mm)

• Optic nerve resection margin^1-6
• One section demonstrating tumour, demonstrating relationship with pupil and optic nerve^4-6
• Calotte/cap from superior pole if possible but inferior pole if tumour is present superiorly.¹
• Two further representative sections of ocular tissue. Alternatively, submit both remaining calottes after obtaining tumour sections.⁴
• If melanoma is suspected, sample the vortex vessels^1,4-8

In addition to sections described for enucleation specimens, submit representative sections from the nearest orbital soft tissue or cutaneous margins.

Note that it may not be possible to obtain a vortex vein section due to presence of soft tissue. Note that deeper cassettes will be required for thick sections.

If received, submit all lymph nodes and identify the site of each.