Ординатура / Офтальмология / Английские материалы / Applied Pathology for Ophthalmic Microsurgeons_Naumann, Holbach, Kruse_2008

e

Fig. 5.4.18. Teratoid medulloepithelioma in 4-year-old boy with adjacent cataract treated by block excision and extracapsular cataract removal. a, b Preoperatively touching the retrocorneal surface; iris pigment epithelial defect by retroillumination. c Adjacent to tumor (Tu) cataract (arrows). d Excised block 11 mm with tumor in front and behind ciliary body. e Histopathology. Cornea (C), Sclera (S), Lens (L), Trabecular meshwork (TM), Ciliary body (CB).

f Postoperatively no recurrence after 2 years (case reported by Holbach et al.

1985)

b

a

b

Fig. 5.4.20. Episcleral extension of partially necrotic melanocytoma of the ciliary body. a Preoperatively: no significant episcleral hyperemia. b Histopathology showing partially necrotic benign melanocytes. c 6.5 mm tectonic corneal graft 2 years postoperatively

Fig. 5.4.21. Adenoma of the non-pigmented ciliary epithelium extending into the anterior chamber in 62-year- old female patient. a–c Preoperatively including gonioscopy and ultrasound biomicroscopy

Fig. 5.4.21. d After phacoemulsification implantation of rigid PMMA-lens. Ninemillimeter block including tumor, iris, pars plicata of ciliary body (CB) and full thickness sclera and cornea. Ciliary body (CB). e Stained for acid mucopolysaccharides

c

d

e

f

Fig. 5.4.21. f Corneoscleral graft 15 months later with good visual acuity edge of anterior lens capsule covering endocapsular PMMAlens (arrows) (case reported by Cursiefen et al. 1999)

d

a

Fig. 5.4.23. Leiomyoma of ciliary body and choroid with collateral and distant retinal detachment in 17-year-old boy treated by enucleation. a Preoperatively showing extensive collateral detachment (CD). b, c Histology showing collateral detachment, ciliary body (CB) and retinoschisis (RS) overlying the tumor. Choroid and retina in cross-section of globe

opposite to tumor arteficial- c ly detached

˜

Fig. 5.4.22. d Postoperatively (case reported by Naumann et al. 1976)

b

5.4.3.4.1

Block Excision of Localized Tumors of the Anterior Uvea

The anterior uvea is only justified if there is no evidence of seeding of tumor cells into the aqueous and/or vitreous cavity. Biocytology – that is slit lamp examination by × 40 magnification – allows recognition of individual tumor cells against a background of blue-gray iris tissue on the lens surface and/or fundus red (see Chapter 5.3). Against the backdrop of a brown iris this is often difficult or impossible to recognize (Fig. 5.4.11). Of 104 consecutive expanding tumors of the ciliary body, 26 were histopathologically benign. Among the malignant types melanomas were the most common (Table 5.4.7; Fig. 5.4.15 – 22; 5.4.24).

Normal intraocular pressure postoperatively can be maintained if not more than 150° (or 5 clock hours) of the circumference of the pars plicata is excised. Surprisingly the block excision – contrary to our original concerns – does not usually create a cyclodialysis and is not associated with persisting ocular hypotony if 210° of the pars plicata is preserved. It is not well understood why the unavoidable opening of the supraciliary space associated with block excision does not induce a persisting ocular hypotony (Tables 5.4.1, 5.4.2).

Reasons for this radical approach for tumors of the anterior uvea are: (1) uveal malignant melanomas have a tendency to invade the sclera, (2) the extent of the scleral invasion cannot be judged clinically if the tumor is non-pigmented, (3) every involvement of the iris root indicates invasion of the ciliary body and cannot be separated from the pars plicata of the ciliary body. Therefore an iridectomy cannot achieve a curative excision in processes of the iris root (Table 5.4.5).

5.4.3.4.2

Block Excision of Epithelial Ingrowth

(1) Both the diffuse and cystic variants show marked variable thickness of the lining epithelial layer from 20 to – often only 1 or 2 cell layers. This delicate structure cannot be manipulated and separated mechanically or uniformly destroyed by alcohol injection and other toxic substances. (2) Reliable complete removal is only possible by removing also the adjacent tissue “acting as a shell.” (3) The thickness of the epithelial layer is variable and cannot be destroyed with uniform certainty by lasers or coagulation. (4) The location and extent of the tracks connecting the surface epithelium and the displaced intraocular elements cannot be determined clinically, unless there is an obvious external fistula. (5) Large cystic epithelial ingrowth can be reduced in diameter if part of the fluid within the cyst is drained (via an access later removed) and the diameter of the cyst compressed by injection of Healon into the anterior chamber outside the cyst. This permits a smaller diameter of the block excision without risking incomplete removal (Table 5.4.6; Naumann and Völcker 1975; Naumann and Rummelt 1990, 1992a, b, 1997; Rummelt et al. 1993, Fig. 5.4.26 – 31).

Important: Attempts to treat cystic epithelial ingroth with laser-puncture or sector-iridectomy shall convert the process to the diffuse type – originating from remaining epithelium in the angle at the face of the ciliary body (Groh et al. 2002; Viestenz et al. 2003).