Last revised 28 May 2008
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Eye (Ophthalmic) Pathology Books
Eye-general
Normal anatomy, autopsy findings, trisomy 13, trisomy 21, congenital rubella syndrome, cyclopia
Conjunctiva
Grossing, normal anatomy/histology, actinic keratosis, ataxia-telangiectasia, benign melanosis, caruncle tumors, conjunctival intraepithelial neoplasia, cystinosis, cysts, dermoid, dysplasia, ephelides, fibrous histiocytoma, graft versus host disease, hereditary benign intraepithelial dyskeratosis, keratoacanthoma, leukoplakia, lymphoid hyperplasia, myxoma, nevi, ocular cicatricial pemphigoid, oncocytoma, pinguecula, plasmacytoma, primary acquired melanosis, pseudoepitheliomatous hyperplasia, pterygium, pyogenic granuloma, sarcoidosis, squamous papilloma, steatocystoma simplex, Sturge-Weber syndrome
Conjunctivitis: general, acute hemorrhagic, allergic, arsenic, chronic, cicatrizing, giant papillary, granulomatous, infectious, ligneous, trachoma
Carcinoma: adenoid squamous carcinoma, basal cell carcinoma, carcinoma in situ, lymphoepithelioma-like carcinoma, metastases, mucoepidermoid carcinoma, sebaceous carcinoma, spindle cell carcinoma, squamous cell carcinoma
Other malignancies: Kaposi’s sarcoma, lymphoma, malignant fibrous histiocytoma, melanoma, rhabdomyosarcoma
Miscellaneous: tumor features to report, TNM staging for carcinoma, TNM staging for melanoma
Cornea
Normal anatomy/histology, grossing, acanthamoeba, actinic band keratopathy, aphakic bullous keratopathy, blood staining, bullous keratopathy, calcific band keratopathy, chronic active keratopathy, collagen-rich crystalloids, corneal dystrophy, epithelial ingrowth, Fuchs dystrophy, graft failure, herpes simplex keratitis, infectious keratitis, keratoconus, keratomalacia, limbus, nonspecific responses, pannus, pseudoexfoliation syndrome, rheumatoid arthritis, transplant, ulceration, tumor features to report
Eyelid
Inflammatory disorders: chalazion, mites, molluscum contagiosum, necrobiotic xanthogranuloma, Prototheca, pseudorheumatoid nodules, pyogenic granuloma, silica granuloma, stye
Tumors: general
Adnexal tumors: adenocarcinoma, eccrine acrospiroma, eccrine carcinoma, pleomorphic adenoma, sebaceous gland adenoma, sebaceous gland carcinoma, sweat gland carcinoma, syringoma, trichilemmal cell tumor, trichilemmoma, trichoepithelioma, trichofolliculoma
Melanocytic tumors: melanoma, melanosis oculi, nevi, nevus of Ota
Other tumors: actinic keratosis, amyloidosis, basal cell carcinoma, cysts, dermoid cyst, hemangioma, Kaposi sarcoma, keratoacanthoma, Merkel cell carcinoma, metastases to eyelid, myxoma, neurofibroma, phakomatous choristoma, pilomatrixoma, pleomorphic adenoma, port wine stain, seborrheic keratosis, squamous papilloma, squamous cell carcinoma, xanthelasma
Miscellaneous: tumor features to report, TNM staging for carcinoma
Glaucoma
General, congenital glaucoma, primary glaucoma, secondary glaucoma, degenerative changes
Globe
General, grossing, inflammation, leukemia, lymphoma, metastases, phthisis bulbi, trauma
Lacrimal duct/gland
General, adenocarcinoma, adenoid cystic carcinoma, dacryoadenitis, dacrocystitis/canaliculitis, dacryoliathiasis, ectopic, malignant mixed tumor, melanoma, Mikulicz’s disease, mucocele, oncocytoma, papilloma, pleomorphic adenoma, squamous cell carcinoma, transitional cell carcinoma, TNM staging for carcinoma of lacrimal gland
Lens and vitreous humor
General, Alport’s syndrome, cataract, dislocation, persistent hyperplastic primary vitreous, phacoanaphylactic endophthalmitis, prosthetic intraocular lens, pseudoexfoliation, vitreous pathology
Orbit and optic nerve
General, alveolar soft parts sarcoma, anterior ischemic optic neuropathy, coloboma, dermoid cyst, drusen, dysthyroid ophthalmopathy, epithelial cyst, Erdheim-Chester, fibrous dysplasia, fibrous histiocytoma, giant cell angiofibroma, glioma of optic nerve, glioma of orbit, granulocytic sarcoma, Grave’s disease, hemangioblastoma, hemangioma, hemangiopericytoma, idiopathic sclerosing inflammation, inflammatory processes, inflammatory pseudotumor, Kimura’s disease, Langerhans cell histiocytosis, lymphangioma, lymphoid hyperplasia, lymphoma, melanocytoma, meningioma, metastases to orbit, mucocele, neurofibroma, nevus, optic atrophy, papilledema, plasmacytoma, rhabdomyosarcoma, Schnabel cavernous degeneration of optic nerve, schwannoma, shaken baby syndrome, sinus histiocytosis, solitary fibrous tumor, subconjunctival herniated orbital fat, temporal arteritis, teratoma, Wegener’s granulomatosis, TNM staging for sarcoma of orbit
Retina
General, adenocarcinoma, astrocytic tumor, Behcet’s disease, central retinal artery occlusion, central retinal vein occlusion, CMV, Coats’ disease, cystic macular edema, detachment, diabetes, hemangioblastoma, hypertension, lattice degeneration, macular degeneration, massive retinal gliosis, myxopapillary ependymoma, peripheral cystoid degeneration, pleomorphic xanthoastrocytoma, retinal dysplasia, retinitis pigmentosa, retinoblastoma, retinocytoma, retrolental fibroplasia, sickle cell retinopathy, toxoplasmosis, tuberous sclerosis, visceral larva migrans, von Hippel-Lindau disease, Wyburn-Mason syndrome
Miscellaneous: tumor features to report-retinoblastoma, TNM for retinoblastoma
Uvea (iris, choroid and ciliary body), limbus and sclera
Choroid-general, ciliary body-general, iris-general, sclera-general, adenocarcinoma of ciliary epithelium, adenoma of pigmented ciliary epithelium, aniridia, anterior chamber cleavage syndrome, blue sclera, coloboma, diffuse uveal melanocytic proliferation, Fuchs’ adenoma, glioneuroma, hemangioma, herpes zoster, hypertensive changes, idiopathic solitary granuloma, iris pigment epithelial cyst, juvenile xanthogranuloma, leiomyoma, Lisch nodules, medulloepithelioma, melanocytoma, melanoma, mesenchymoma, nevi, osteoma, post-traumatic uveitis, rubeosis iridis, sarcoidosis, scleritis, senile scleral plaques, sympathetic uveitis, uveitis, uveomeningoencephalitic syndrome
Miscellaneous: tumor features to report, TNM for uveal melanoma
Primary references for eye chapter
AJCC Cancer Staging Manual (6th Ed)
American Journal of Clinical Pathology, (AJCP), January 1975 to October 2007
American Journal of Surgical Pathology (AJSP), March 1977 to September 2007
Archives of Pathology and Laboratory Medicine (Archives), January 1976 to September 2007
Human Pathology (Hum Path), March 1970 to September 2007
Modern Pathology (Mod Path), January 1988 to October 2007
Font: Tumors of the Eye and Ocular Adnexa (AFIP Atlas of Tumor Pathology, Series 4, Vol 5); 2006
McLean: Tumors of the Eye and Ocular Adnexa (Atlas of Tumor Pathology, Series 3, Vol 12)
Mills: Histology for Pathologists (3rd Ed); Lippincott Williams & Wilkins, 2006
Mills: Sternberg’s Diagnostic Surgical Pathology (4th Ed); Lippincott Williams & Wilkins, 2004
Rosai, J: Ackerman’s Surgical Pathology (9th Ed); 2004
Websites: University of Utah, University of Illinois at Chicago
Journal search terms: eye, conjunctiva, choroid, ciliary body, cornea, eyelid, globe, iris, lacrimal, lens, orbit, retina, uvea, vitreous and each disease entity listed
Please refer to these primary references for more detailed discussions and additional images
Eye-General
Anterior chamber: between iris and corneal endothelium; contains Schlemm’s canal, trabecular meshwork and aqueous humor
Micro images: anterior chamber; anterior and posterior chambers
Bowman’s layer: see cornea
Bruch’s membrane: see uvea (choroid)
Canaliculi: see lacrimal duct / gland
Caruncle: see conjunctiva
Choriocapillaris: see uvea (choroid)
Choroid: see below
Ciliary body: see below
Conjunctiva: see below
Cornea: see below
Descemet’s membrane: see cornea
Episclera: see sclera
Eyelid: see below
Fornix: see conjunctiva
Fovea centralis: see retina
Globe: see below
Intraocular tissues: uveal tract (iris, choroid and ciliary body), retina, lens and vitreous
Iris: see below
Lacrimal duct / gland: see below
Lacrimal sac: see lacrimal duct / gland
Lamina cribrosa: see orbit and optic nerve
Lamina fusca: see sclera
Lens: see below
Limbus: see below
Macula: see retina
Macula lutea: see retina
Nasolacrimal duct: see lacrimal duct / gland
Optic nerve: see below
Ora serrata: see retina
Orbit: see below
Normal anatomy of eye (continued)
Palpebral fissure: longitudinal opening for the eyes between the eyelids
Pars plicata: see uvea (ciliary body)
Plica semilunaris: see conjunctiva
Posterior chamber: space in the eye between the iris and the suspensory ligament of the lens and the ciliary processes; contains aqueous humor
Micro images: anterior and posterior chambers
Puncta: see lacrimal duct / gland
Pupil: see uvea (iris)
Retina: see below
Schlemm’s canal: see uvea (limbus)
Sclera: see below
Trabecular meshwork: see uvea (limbus)
Trochlea: see orbit and optic nerve
Uvea: see below
Vitreous humor: see below
Zonule: see uvea (ciliary body)
Drawings: schematic of eye #1; #2; section of eyeball; anterior half of eye; posterior half of eye
Virtual slides: whole mount of eye
Most common findings are diabetic retinopathy (14%), age related macular degeneration (5%), melanoma of uvea or choroid, metastatic carcinoma (Archives 2001;125:1193)
Rare findings are retinitis pigmentosa
May be useful for forensic cases (Leg Med (Tokyo) 2003;5 Suppl 1:S288)
Trisomy 13 (Patau syndrome) and eye
Almost all patients have severe ocular abnormalities
80% have microphthalmos (abnormally small eyes), cyclopean synophthalmus (fused eyes), colobomas, cataracts (Am J Ophthalmol 2006;141:1057), or persistent hyperplastic primary vitreous
75% have retinal dysplasia (tubular and rosette-like structures)
65% have cartilage within coloboma
60% have anterior chamber dysgenesis (defective development of cornea, iris or anterior chamber angle), often associated with congenital glaucoma
Case reports: tarsal kink (Ophthal Plast Reconstr Surg 2003;19:408)
Clinical images: cyclopia with proboscis #1; #2
References: Oftalmol Zh 1990;7:423, Wikipedia, Orpha.net
Less severe than trisomy 13
Hypertelorism (widely spaced eyes), lid abnormalities (oblique, arched palpebral fissures), epicanthus (vertical fold of skin on either side of nose), ectropion and eversion of upper eyelid; also keratoconus (may be due to knuckle rubbing) and retinal dysplasia
Also esotropia, significant refractive errors (43% at school age, Dev Med Child Neurol 2007;49:513), hyperemic optic disc, retinal pigment epithelial atrophy, prominent whitened choroidal vessels, chronic blepharoconjunctivitis, nasolacrimal duct obstruction (Ophthalmology 2003;110:1437)
Iris is speckled due to Brushfield spots (ringlike foci of iris hypoplasia surrounded by normal stroma), present in 85% with blue or hazel eyes (Indian Pediatr 2002;39:97), uncommon in Asian children with Down’s syndrome (Eye 2002;16:710)
Cataracts develop at age 15+ years
Recommended that Down’s patients have initial eye exam at 6 months of age, then annually
Clinical images: Brushfield spots
Molecular images: karyotype #1; #2
References: eMedicine
Congenital rubella syndrome and eye
Associated with cataracts (90%), iris abnormalities, retinopathy, congenital glaucoma, microphthalmos (Indian J Ophthalmol 2002;50:307)
Cataracts are due to retention of cell nucleus in lens cells
Rubella virus can survive within these cells for years; surgery on these infants may cause uveitis or endophthalmitis, due to release of virus; cataract surgery has less than optimal results (J AAPOS 2003;7:91)
Iris abnormalities include poorly developed dilator muscle and necrotic appearing epithelium; granulomatous inflammation is common; iris looks leathery since it doesn't dilate normally
Rubella retinopathy consists of alternating atrophy and hypertrophy of retinal pigment epithelium (salt and pepper appearance); may have subretinal neovascularization
Incidence of 0.6 per 1000 live births in Oman (Arch Ophthalmol 2004;122:541)
Disease persists in industrialized countries in those infected prior to 1969 vaccine (Optometry 2002;73:418)
Clinical images: bilateral cataracts
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Congenital facial abnormality with one medial eye (either single eye or 2 fused eyeballs) and proboscis (tubular appendage) superior to the orbit
Usually associated with holoprosencephaly, due to impaired midline cleavage of embryonic forebrain
Incidence of 1 per 100K births
Incompatible with life
Associated with trisomy 13, trisomy 18, triploidy; also other chromosomal abnormalities
May be due to malfunction of sonic hedgehog protein
Case reports: Archives 2005;129:e19
Clinical images: various images; trisomy 13 - cyclopia with proboscis #1; #2
Whole mount: large eye with two lenses and two retinas
Conjunctiva
Grossing of conjunctiva
Specimens are thin and tend to fold when placed in fixative
Surgeon should spread lesion onto filter paper, allow to dry for a few seconds, then place in specimen container (see University of Illinois at Chicago protocol)
Relevant landmarks should be labeled
For lesions that extend to limbus, cut so sections are perpendicular to limbus
Don’t use methylene blue or toluidine blue ink for margins, as they bleed into sample
Don’t place specimens on sponges, which expand in fixative and distort specimen
Normal anatomy / histology of conjunctiva
Thin mucous membrane that lines inner eyelid (tarsal or palpebral portion) and anterior surface of ocular globe (bulbar portion)
Has protective function and also allows eyelids to move smoothly over globe
Has rich lymphatic channels connecting to parotid and submandibular nodes
Bulbar conjunctiva: covers anterior surface of sclera and surface epithelium of cornea; cuboidal and columnar epithelium; goblet cells more common in inferior and nasal parts, particularly near fornix; substantia propria has loose connective tissue with scattered inflammatory cells and deep dense collagen
Caruncle: small (5 x 3 mm) fleshy nodular prominence in nasal portion of interpalpebral fissure (inner angle of eye) between skin and conjunctiva; lined by conjunctival epithelium and nonkeratinized squamous epithelium; contains cutaneous adnexal structures, accessory lacrimal gland tissue
Fornix: portion of conjunctiva that forms a cul de sac where it reflects onto surface of the globe; pseudostratified columnar epithelium rich in goblet cells (may mimic dysplasia); contains accessory lacrimal tissue, ductules of main lacrimal gland and lymphoid follicles; site of sarcoid granulomas
Limbal conjunctiva: annular rim of conjunctiva extending from cornea to 3 cm on bulbar surface; contains corneal epithelial stem cells in its basal layers; also branching dendritic melanocytes
Palpebral (tarsal) conjunctiva: lines interior of eyelid; has pseudoglands of Henle (invaginations of surface epithelium that form tubular and cystic structures), hair follicles (Cornea 2006;25:781); substantia propria is more uniform than in bulbar conjunctiva and is more closely attached to tarsus (so invasive lesions appear clinically flat), has arterioles, veins and complex capillary network, myelinated and nonmyelinated branches of trigeminal nerve, lymphoid aggregates near fornices, acini and ducts of accessory lacrimal glands of Wolfring and Kraus; conjunctiva becomes papillary with allergic or bacterial conjunctivitis
Plica semilunaris (semilunar fold): arc shaped fold of conjunctiva just lateral to caruncle; may be vestigial nictitating membrane of lower species; contains abundant goblet cells and rarely cartilage or smooth muscle
Regional lymph nodes: preauricular/parotid (drains temporal lymphatics), submandibular (drains nasal and caruncle lymphatics)
Micro: mucous membrane with epithelium and substantia propria; has 2-5 layers of columnar or cuboidal cells resting on continuous basal lamina; epithelial cells may have eosinophilic cytoplasm and apical snouts; also goblet cells that secrete mucin, melanocytes (more prominent in dark skinned patients), Langerhans cells and intraepithelial lymphocytes (conjunctival associated lymphoid tissue-Invest Ophthalmol Vis Sci 2000;41:1270)
Micro images: bulbar conjunctiva #1; #2-stratified nonkeratinizing squamous epithelium with goblet cells covers a vascular lamina propria; conjunctival goblet cells (right) facing pigmented corneal epithelium (left) near junction; palpebral conjunctiva rests upon tarsal plate
Positive stains: CK19, MUC1 and MUC4 (Invest Ophthalmol Vis Sci 2000;41:398), MUC7 (Cornea 2003;22:41); very low levels of MUC2 and MUC5AC (Invest Ophthalmol Vis Sci 2000;41:703),
Negative stains: CK3
References: Hum Path 1997;28:1348 (cytokeratin)
Actinic keratosis of conjunctiva
Also called leukoplakic lesions, ultraviolet light related lesions
Usually limbal conjunctiva at advancing head of pterygium
Case reports: 73 year old man (J Fr Ophtalmol 1998;21:458), bilateral limbus lesions (J Fr Ophtalmol 1992;15:65), pigmented lesion (Korean J Pathol 2004;38:113), 42 year old man with conjunctival mass (Indian J Ophthalmol 2004;52:154)
Clinical images: elevated white limbal tumor
Gross: thickened conjunctiva with leukoplakia
Micro: sharply demarcated; mild atypia of epithelium, acanthosis, parakeratosis, hyperkeratosis but normal polarity, normal maturation; elastotic degeneration and lymphocytes in substantia propria
Micro images: mild epithelial atypia, degenerative changes in substantia propria #1; #2; sharply demarcated intraepithelial lesion with acanthosis, moderate atypia, parakeratosis and subepithelial actinic elastosis; intraepithelial corneal lesion with severe atypia and parakeratosis #1; #2; acantholytic lesion with subepithelial lymphocytes; atrophic lesion with atypia
DD: dysplasia (more diffuse and gelatinous, Can J Ophthalmol 1995;30:312), carcinoma in situ
Ataxia-telangiectasia and conjunctiva
Autosomal recessive disease; previously called Louis-Bar syndrome
Characterized by progressive cerebellar ataxia, oculocutaneous telangiectasia and recurrent respiratory and sinus infections
Telangiectatic blood vessels in bulbar conjunctiva in >90% (Am J Ophthalmol 2002;134:891)
Mostly visible by age 4-5 years, primarily within palpebral fissure (Acta Ophthalmol Scand 2007;85:557)
Clinical images: prominent conjunctival blood vessels #1; #2
References: eMedicine #1; #2; Atlas of Genetics and Cytogenetics
Benign melanosis of conjunctiva
See also primary acquired melanosis
May be normal finding in dark skinned individuals - bilateral, continues throughout life
Present in 92% of blacks, 36% of Asians, 28% of Hispanics, 5% of whites
Uncommon finding in Laugier-Hunziker syndrome (Arch Dermatol 2007;143:631)
Clinical images: racial melanosis
Micro: dense pigmentation at basal layer of epithelium, but normal number of melanocytes
Micro images: dendritic melanocytes are present in racial melanosis
Negative stains: HMB45 in racial melanosis (Histopathology 2001;39:426)
DD: melanocyte migration associated with inflammation or trauma, medications (epinephrine, tetracycline, silver-containing products), ochronosis, iron containing foreign bodies, early primary acquired melanosis (melanocytic proliferation is present), ocular melanocytosis (pigmentation of ocular structures due to abnormal migration of melanocytes during development)
4% of conjunctival tumors
May include any tumor type that occurs in conjunctiva, skin or lacrimal gland
Usually papilloma or nevus (Am J Ophthalmol 2006;142:448)
5% are malignant - melanoma, squamous cell carcinoma, sebaceous gland carcinoma, lymphoma
May be due to spread from other conjunctival, eyelid or lacrimal tumors
Case reports: basal cell carcinoma #1 in 80 year old man (J Cutan Pathol 2005;32:502), #2 in 82 year old man (Ophthal Plast Reconstr Surg 2006;22:313), inflammatory pseudotumor (J Fr Ophtalmol 2003;26:204), sebaceous gland carcinoma in 68 year old woman (Cornea 2006;25:858); metastasis from pulmonary large cell neuroendocrine carcinoma (Am J Ophthalmol 2002;134:438)
Conjunctival intraepithelial neoplasia
Precursor to squamous cell carcinoma
Dysplastic changes of conjunctiva ranging from dysplasia to carcinoma in situ
Incidence of 1.9 cases per 100K per year
Associated with ocular pigmentation, tobacco use, sun exposure (Br J Ophthalmol 2003;87:396), exposure to petroleum products, chronic cyclosporine for transplants
HIV is associated with aggressive tumors presenting at younger ages
HPV 6/11 in 38%, HPV 16 in 30-58%, HPV 18 in 50-57% (Ophthalmology 2002;109:542)
Treatment: excision, but often recurs; topical interferon-alpha-2b (Ophthalmologe 2006;103:124), mitomycin (Arch Soc Esp Oftalmol 2004;79:375) or adjuvant cryotherapy reduces recurrence rate; usually does not become invasive with recurrence; amniotic membrane grafts may be useful (Chang Gung Med J 2003;26:737)
Gross: sharply circumscribed limbus lesion; annular and gelatinous; may see delicate epithelial proliferation of cornea with indirect illumination
Micro: sharply circumscribed atypia; dysplasia begins in basal layers and extends towards surface; large or small squamous cells, may be spindled; often atypical mitotic figures at all levels of epithelium; fronds of proliferating blood vessels and connective tissue resemble papilloma; rarely HPV related changes (koilocytes); usually NO keratinization or dyskeratosis; no invasion of epithelial basal membrane
Positive stains: p53, Ki-67, HPV
DD: UV related lesions (without dysplasia), sebaceous gland carcinoma, adenocarcinoma from eyelid glands of Moll, melanosis
Must fix tissue in absolute alcohol, not formalin, or crystals will be dissolved
Micro images: cystinosis in conjunctiva of child
DD: gout, hypergammaglobulinemia
See also steatocystoma simplex
Most are acquired due to surgery (Ophthalmology 2006;113:1049), trauma (Br J Anaesth 2005;95), foreign bodies or chronic inflammation; also parasitic cysts
Usually on nasal conjunctiva and lower fornix
Most (65%) conjunctival nevi are also cystic (Curr Opin Ophthalmol 2007;18:351)
Cyst may be injected with Healon V and trypan blue to facilitate visualization and excision (Cornea 2005;24:759)
Dermoid cysts: lined by stratified squamous epithelium, contains cutaneous adnexae (Ophthal Plast Reconstr Surg 2006;22:137); see also dermoid tumor below
Inclusion cysts: one or two cell lining of non-keratinized epithelium containing goblet cells; may have apocrine snouts resembling apocrine glands; may be associated with Stevens-Johnson syndrome (Ophthal Plast Reconstr Surg 2006;22:475)
Clinical images: multiloculated cyst post-anesthetic injection; large cyst
Gross: usually translucent to light blue
Dermoid tumor and other congenital lesions of conjunctiva
A type of choristoma (congenital, non-neoplastic lesion composed of cytologically normal tissue not normally found at that location), often at limbus
Mainly children
No malignant potential
May be associated with colobomas of iris and ciliary body, Goldenhar’s syndrome (ocular dermoid tumors, extra-auricular appendages, vertebral anomalies, East Afr Med J 2002;79:502), organoid nevus syndrome (also called linear nevus sebaceous of Jadassohn, Br J Ophthalmol 1987;71:268)
Gross: bulbar tumors are firm, localized, elevated, opaque, yellow-white masses at limbus
Micro:
Dermoid: solid (not cystic) choristoma mass with surface epithelium resembling epidermis and dermis and containing a few hairs, overlying thick bundles of collagen, which make up bulk of mass (eMedicine)
Complex choristoma: cartilage, lacrimal tissue, smooth muscle, adipose tissue, neural tissue (Ophthalmology 1987;94:1249); may be confused with prolapsed lacrimal gland (Acta Ophthalmol Scand 2005;83:100)
Osseous choristoma: small, solid, circumscribed, red-white bony lesion behind limbus and between superior and lateral rectus muscles; composed of compact lamellar bone surrounded by dense, collagenous bone (Br J Ophthalmol 1979;63:173, Ophthalmic Surg Lasers 2002;33:410)