Ординатура / Офтальмология / Английские материалы / Essentials in Ophthalmology Oculoplastics and Orbit_Guthoff, Katowitz_2007

204Rehabilitation of the Exenterated Orbit

tion in which the exenteration was carried out. Other patients had had a previous exenteration performed elsewhere for malignancy.

come because the reduction in volume involves the thickness of the flap more than the length, thus leading to a relatively stable result.

Summary for the Clinician

Advantages:

-Frontalis muscle transfer represents a suitable alternative technique to the temporalis muscle technique for rebuilding a socket capable of supporting a prosthesis

Disadvantages:

-Reduction of volume can occur because of the shrinkage of the flap

-Some patients do not like a scar in the frontal area even if it becomes more acceptable with time

Summary for the Clinician

Advantages:

-The flap is already covered by the skin and therefore “ready” to accommodate the prosthesis without a second procedure

-No modification of the volume with time

Disadvantages:

-Scarring of the skin at the donor site can be cosmetically unacceptable

simple total exenteration. It can be used primarily, immediately after exenteration, or secondarily, even in contracted sockets with poor or absent blood supply. We have successfully used this procedure in patients with contracted sockets who have had extensive loss of tissue, few areas of granulation, and poor bloody supply. Usually, the cavity is covered by a thick layer of skin. All such patients who have undergone this technique have achieved a final orbital cavity with sufficient room to accommodate a prosthesis. Although this technique is a two-step procedure, the second stage is very quick and can be done under local anesthesia. The first stage of the procedure permits management of the deep orbit and the eyelids at the same time. The vascularized flap can “cover” the posterior part of the orbit and the skin layer that was previously lining the cavity can be utilized alone or with local flaps to form the eyelids. In this fashion, the deep orbit is “covered” by the flap (more than “filled”) and this is an important advantage. Although the reduction in volume of the flap due to postsurgical shrinking can occur, it will not usually influence the postsurgical out-

13.3.4 Oculofacial Prostheses

Successful osseointegration has been achieved in about 90% of the patients reported and because of this the use of these implants has increased in recent years. In cases of extensive resections, even when less bone substance remains, application of these techniques is still possible and usually recommended. Another advantage is that postoperative radiation is still possible.

Summary for the Clinician

Advantages:

-High rate of success with the recent techniques

-Favorablefects option for covering large de-

-Postoperative radiotherapy is more feasible than with the use of local flaps

Disadvantages:

-Deterioration of the materials

-Expensive procedure

-Unpleasant odors sometimes noticed from the covered areas

References

1.Atabay K, Atabay C, Yavuzer R, Demirkan F, Latifoglu O (1998) One-stage reconstruction of eye socket and eye lids in orbital exenteration patients. Plast Reconstr Surg 101:1463–1470

2.Bartisch G (1583) Ophthalmodoulcia. Dresden 3:208

3.Bartley GB, Garrity JA, Waller RR, et al. (1989) Orbital exenteration at the Mayo Clinic 1967– 1986. Ophthalmology 96:468–474

4.Bonavolonta G (1992) Frontalis muscle transfer in the reconstruction of the exenterated orbit. Adv Ophthalmic Plast Reconstr Surg 9:239–242

5.Catalano PJ, Laidlaw D, Sen C (2001) Globe sparing orbital exenteration. Otolaryngol Head Neck Surg 125:379–384

6.Crow ML, Crow FJ (1976) Resurfacing large cheek defects with rotation flaps from the neck. Plast Reconstr Surg 58:196–200

7.Donahue PJ, Liston SL, Falconer DP, Manlove JC (1989) Reconstruction of orbital exenteration cavities. The use of the latissimus dorsi myocutaneous free flap. Arch Ophthalmol 107:1681–1683

8.Dortzbach R, Hawes M (1981) Midline forehead flap in reconstructive procedure of the eyelids and exenterated socket. Ophthalmic Surg 12:257–268

9.Harting F, Koorneef L, Peeters HJF, et al. (1985) Glued fixation of split-skin graft to the bony orbit following exenteration. Plast Reconstr Surg 76:633–635

10.Holmes AD, Marshall KA (1979) Use of the temporalis muscle flap in blanking out orbits. Plast Reconstr Surg 63:336–343

11.Kaplan I, Goldwyn RM (1978) The versatility of the laterally based cervicofacial flap for cheek repairs. Plast Reconstr Surg 61:390–393

12.Konstantinidis L, Scolozzi P, Hamedani M (2006) Rehabilitation of orbital cavity after total orbital exenteration using oculofacial prostheses anchored by osseointegrated dental implants posed as a one-step surgical procedure. Klin Monatsbl Augenheilkd 223(5):400–404

13.Kroll SS, Reece GP, Robb G, Black J (1994) Deepplane cervicofacial rotation-advancement flap for reconstruction of large cheek defects. Plast Reconstr Surg 94:88–93

References 205

14. Levin PS, Dutton JJ (1991) A 20 year series of orbital exenteration. Am J Ophthalmol 112:496–501

15.Marques A, Brenda E, Magrin J, Kowalski LP, Andrews JM (1992) Critical analysis of methods of reconstruction of exenterated orbits. Br J Plast Surg 45:523–528

16.Mauriello JA Jr, Han KH, Wolfe R (1985) Use of autogenous split-thickness dermal graft for reconstruction of the lining of the exenterated orbit. Am J Ophthalmol 100:465–467

17.Nerad JA, Carter KD, LaVelle WE, Fyler A, Branemark PI (1991) The osseointegration technique for the rehabilitation of the exenterated orbit. Arch Ophthalmol 109(7):1032–1038

18.Ohtsuka H (1988) Eye socket and eyelid reconstruction using the combined island frontal flap and retroauricular island flap: a preliminary report. Ann Plast Surg 20:244

19.Putterman AM (1986) Orbital exenteration with spontaneous granulation. Arch Ophthalmology 104:139–140

20.Rahman I, Cook AE, Leatherbarrow B (2005) Orbital exenteration: a 13 year Manchester experience. Br J Ophthalmol 89(10):1335–1340

21.Reese AB, Jones IS (1961) Exenteration of the orbit and repair by transplantation of the temporalis fascia. Am J Ophthalmol 51:217–227

22.Sandner A, Bloching M (2004) [Experiences with a new plate-like implant system (Ti-Epi- plating System) for rehabilitation of orbital and midfacial defects.] Klin Monatsbl Augenheilkd 221(11):978–984

23.Savage RC (1983) Orbital exenteration and reconstruction for massive basal cell and squamous cell carcinoma of cutaneous origin. Ann Plast Surg 10:458–466

24.Sheilds JA, Sheilds CL, Suvarnamani C, et al. Orbital exenteration with eyelid sparing: indications, technique and results. Ophthalmic Surg 122:292–297

25.Shore JW, Burks R, Leone CR Jr, et al. (1986) Dermis fat graft for orbital reconstruction after subtotal exenteration. Am J Ophthalmol 102:228–236

26.Uchinuma E, Sakurai H, Shioya N (1989) Anterofrontal superficial temporal artery island flap for full-thickness eyelid reconstruction. Ann Plast Surg 23:433

206Rehabilitation of the Exenterated Orbit

27.Urken ML, Turk J, Weimberg H, Vickery C, Biller HF (1991) The rectus abdominis free flap in head and neck reconstruction. Arch Otolaryngol Head Neck Surg 117:857–866

28.Van der Meulen JC (1998) Invited discussion (for Ata Goi et al.). One-stage reconstruction of eye socket and eye lids in orbital exenteration patients. Plast Reconstr Surg 101:1471–1472

208 Salivary Gland Transplantation

14.1 Introduction

14.1.1Background and Surgical Principles

In absolute tear deficiency, severe ocular surface damage can progress despite copious use of artificial tear substitutes, resulting in persistent pain and permanent loss of vision [29]. In this situation, mucous membrane grafting alone will not provide sufficient lubrication to alleviate symptoms or to enable successful ocular surface reconstruction. Several studies have demonstrated that oral and nasal mucosa could successfully be used to reconstruct the fornices and provide mucin for

lubrication. However, after neither oral nor nasal mucosal transplantation did lubrication increase to a level sufficient to sustain a healthy corneal graft [14, 17, 32].

The minor (labial) and the major salivary glands have been used as autologous sources of lubrication in severe dry eye [2, 5, 6, 7, 23, 30]. The surgical principles reported include (Fig. 14.1):

•Transplantation of labial mucosa with attached minor labial salivary glands to the posterior lamella of the eyelids

•Transposition of the excretory duct (Stensen’s duct) of the parotid gland to the lower conjunctival sac

•Free transplantation of the sublingual gland to the upper conjunctival fornix without microvascular anastomosis

nutrient and microbicidal factors, such as albumin, lipids, immunoglobulins, and proteases. The secretion of the minor salivary glands is pre-

sis

These techniques vary significantly in the volume and quality of substitute lubrication they provide (Table 14.1).

14.1.2.Quantitative

and Compositional Differences Between Saliva and Normal Tears

The total volume of saliva secreted per day is approximately 103 larger than the total tear volume, which is around 1–2 ml. The major salivary glands account for most of the stimulated secretion. Without gustatory stimulation approximately 50% of saliva is secreted by the minor salivary glands in the oral mucosal lining, 30%

seromucinous (predominantly serous), although it has a substantially higher viscosity than tears and the sublingual gland saliva is mucoserous (predominantly mucinous). The parotid gland produces a serous, and hence less tear-like, saliva (Table 14.1) [25].

Relevant differences between tears and saliva include some specific enzymes and the osmolality. In patients in whom a salivary gland or its secretory duct is transplanted or transposed, the quality of the ocular surface lubrication will be identical or similar to regular saliva [8]. Due to their specificity, the abundance of salivary enzymes such as amylase has no obvious detrimental effect on healthy human corneal epithelium [2, 9]. However, while tears are isotonic to serum, saliva is relatively hypo-osmolar. If the ocular surface is lubricated with large quantities of hypo-osmolar salivary tears this can result in

crobicidal factors also present in tears.

■The seromucinous SMG saliva is most similar to tears, although it has a much lower osmolality.

14.2 Minor Labial Salivary

Gland Transplantation

Care should be taken not to extend the incision closer than 1 cm to the mucocutaneous junction/ 0.5 cm to the midline of the lip, or to damage the underlying muscle. If left unsutured, the labial wound usually heals rapidly by secondary intention healing within 2–4 weeks.

The recipient bed is prepared by everting the upper or lower eyelid and separating the conjunctiva from the underlying Muller’s muscle with an injection of saline or anesthetic. Next, an incision of approximately 2.5 cm is made along the posterior edge of the tarsal plate and the conjunctiva is dissected posteriorly for about 1.5 cm. The graft is placed in povidone, cleaned, and cut to fit the recipient bed, while carefully preserving any glandular structures, before it is sutured to the recipient bed with 7.0 or 8.0 long-acting absorbable su-

14.2.2 Clinical Results

During the first postoperative month the upper lid is often fairly edematous and should not be everted to avoid damage to the graft. The initially chemotic and avascular graft is usually revascularized within 1 week, which is when patients begin to report some subjective improvement. After 2 weeks, secretion of saliva can often be seen clinically. This is initially fairly viscous, but will become more serous by the end of the first month.

With the original description of the surgical technique in 1998, Murube also reported the results of 6 patients with a mean follow-up of 11 months. In these patients, 1 graft became atrophic, but 5 grafts remained viable and led to increased lubrication and a reduction of symptoms in 4. Mean preoperative Schirmer test results improved from 5.7±3.8 mm to 11.7±9.5 mm [25]. Guerissi reported a patient with a 2-year history of dry eye secondary to Sjögren’s syndrome and severe DE symptoms recalcitrant to any medical treatment who showed significant relief after minor salivary gland transplantation. A biopsy taken 3 months after surgery confirmed the presence of viable salivary gland acini and ducts with mucin content [13]. Soares reported about 37 transplantations in 21 patients with a graft survival rate of 97%. Most of these patients (12) suffered from Stevens-Johnson syndrome-induced severe dry eye and required additional surgery, such as amniotic membrane transplantation, symblepharolysis or other procedures to correct trichiasis. Signs and symptoms, including the need to use artificial tears, and vision improved in 92% of the cases. These results were found to

Fig. 14.3  a Two horizontal sutures running in the graft and subconjunctival tissue can alternatively be used to hold the graft in place. b The suture ends are externalized through the skin and tied together

be stable over a maximum follow-up of 4.5 years. Complications included infection (n = 1) and ptosis (n = 3) [31]. Potential donor site complications include temporary hypesthesia, delayed wound healing, and a reduced volume of the lip. More details on the amount of secretion resulting from this procedure and its impact on the ocular surface in the long term are still required.

Summary for the Clinician

■Sheets of minor salivary glands attached to full-thickness labial mucosa can be transplanted as free grafts to the posterior lamella of the eyelids.

■A small number of early clinical case series reported beneficial effects on signs and symptoms of dry eye.

212 Salivary Gland Transplantation

14.3 Parotid Duct Transposition

The concept of transposing the parotid duct from its original premolar position in the mouth to the lower conjunctival fornix was conceived by Filatov and Chevaljev in 1951 [5] and subsequently modified by others.

14.3.1 Surgical Technique

The initial technique described by Filatov used a cutaneous approach to the parotid duct, until Pierce et al. later described an entirely oral technique [27]. The direct approach uses a preauricular skin incision to visualize and mobilize the entire parotid duct. Following probing, the ostium is excised with a small cuff of buccal mucosa. From the lower anterior end of the incision a subcutaneous tunnel is created by blunt dissection to the inferotemporal conjunctival fornix [1].

The indirect or oral approach consists of the intraoral dissection of a 2 by approximately 7 cm long, anterior-posterior directed strip of fullthickness mucosa centered around and including the ostium of Wharton’s or Stensen’s duct. The duct itself is probed and freed over 2–3 cm from

14 the muscle of the cheek (up to the anterior border of the masseter muscle). The mucosal strip is folded onto itself and sutured over a tube to achieve a total length of 7–8 cm of mobilized “ductal tube.” This is then passed through a tunnel on the periosteum of the zygoma deep to all muscles, vessels, and nerves. Its end enters into and is sutured to the conjunctiva of the inferotemporal conjunctival sac [4, 27].

Early surgical complications include disinsertion/obstruction at the level of the fornix or fistulation of the duct at any position. Contraction or lack of length of the ductal tube frequently resulted in mechanical lower lid entropion or ectropion and this was more common with the transcutaneous approach [4].

14.3.2 Clinical Results

Parotid duct transposition provides copious wetting, but due to a maintained innervation of the parotid gland it is associated with a gustatory reflex epiphora. A number of case reports and

descriptive studies exist, but there are no wellconducted prospective studies with detailed, (semi)quantitative follow-up data [2, 4, 27]. This can lead to traumatic keratitis since the patient frequently has to wipe the eye to remove excess secretion [2]. Until recently, the technique has been popular with veterinary ophthalmologists who have performed it in beagles, who frequently suffer from severe dry eye. From this we know that in addition to gustatory reflex tearing the postoperative course can be complicated by blepharitis, corneal calcifications, and an increased load of colony-forming bacterial units in the conjunctival sac, which, in addition, is altered from a predominantly gram-positive toward a more mixed bacterial flora, without inducing overt ocular surface pathology [11, 26].

Systemic anticholinergics and implantation of a lacrimal bypass tube were suggested to manage salivary epiphora, but these were associated with systemic side effects or were insufficient to drain the excessive volume of ocular surface lubrication. Also, parasympathetic denervation of the gland is impracticable since surgical access is difficult and collateral damage to the facial nerve during such maneuvers is likely. Therefore, the technique is currently rarely practiced in humans.

Summary for the Clinician

■Due to the remaining innervation this procedure results in gustatory reflex tearing, which is reportedly complicated by dermatitis and keratitis.

■The procedure should currently be classified as “historic”.

14.4Sublingual Gland Transposition

Murube was also the first to transplant autologous sublingual gland tissue to the conjunctival fornix in rabbits and humans. According to Sieg, salivary glands tolerate a maximum ischemia of up to one and a half hours at physiological temperatures [30] and without vascular anastomosis sublingual grafts should become completely necrotic within 6 h. From histological studies in rabbits Murube

found that the grafts first underwent partial atrophy before some acinar tissue was regenerated.

14.4.1 Surgical Technique

This involves transconjunctival preparation of a recipient in the temporal upper fornix. A block of sublingual gland together with overlying mucosa measuring approximately 25 × 1 0 × 6 mm is excised and then fixed with transpalpebral sutures to the recipient bed and the lacrimal gland. Finally, the conjunctiva and mucosa are sutured with interrupted absorbable sutures. The concept of surgery was based on the idea that the grafted tissue would become vascularized from the contact area in the recipient bed.

14.4.2 Clinical Results

When Murube performed such free sublingual gland transplants to the superolateral conjunctival fornix of 5 patients with severely aqueous-de- ficient dry eye, due to the absence of any primary vascularization the grafted tissue apparently became necrotic in 2 patients. Of the remaining 3, only 1 showed a minimal increase in Schirmer’s test score from 0 to 2 mm [23]. Since the initial report, this approach seems to have been completely abandoned.

Summary for the Clinician

■Due to the absence of any vascular supply sublingual gland transplants become necrotic and offer little or no improvement in lubrication and symptoms of dry eye.

14.5Submandibular Gland Transposition

Of all procedures involving the transplantation of major salivary glands for severe dry eye – due to some principle advantages – this is the only one currently practiced in humans. The concept involves a free autologous SMG transplanted to the temporal fossa. A microvascular anastomosis

ensures blood supply to the graft and thus longterm survival of the acinar tissue of the gland. The secretion of the SMG is seromucinous and hence capable of replacing both the mucinous and the aqueous components of the normal tear film. The flow rate of saliva from a normal SMG exceeds normal tear production by far. However, intraoperative denervation of the graft reduces this and in addition avoids the gustatory reflex salivation seen after parotid duct transposition. In rats and rabbits the transplanted gland remained viable and successfully prevented corneal ulceration during a follow-up of 6 months [18, 19].

14.5.1 Surgical Technique

Prior to surgery it is of obvious importance to ensure that the potential donor tissue is viable and functional. Minor labial salivary gland biopsy is an accepted reference tissue for excluding a destructive inflammatory process directed against salivary gland tissue in general by means of histological examination. More direct, 99m-Tech- netium scintigraphy with or without parasympathomimetic stimulation is capable of quantifying the secretory capacity of a salivary gland [20].

Surgery is ideally performed under general anesthesia by a collaborative team of maxillofacial and oculoplastic surgeons. In trained hands, the procedure requires 5–6 h of surgical time. First, the SMG and its vascular pedicle are prepared, the secretory duct mobilized at the sublingual caruncle, and the parasympathetic fibers branching out from the lingual nerve severed [6, 7, 22, 23, 30]. Next, a recipient bed is prepared in the temporal fossa by fenestration of the temporalis muscle and preparation of the superficial temporal artery and vein. The original blood supply of the SMG is then ligated, the graft transferred to the recipient bed, and an arterial and venous microanastomosis with the temporal vessels created. The secretory duct is passed subcutaneously to the fornix where it is connected to the conjunctiva prior to skin closure.

14.5.2 Clinical Results

In humans, four independent groups of authors have published clinical results with this procedure