Research from JAMA Ophthalmology — Long-term Risk of Recurrence After Intact Excision of Pleomorphic Adenomas of the Lacrimal Gland

Success after lacrimal surgery is ill defined, and this has led to confusion in the interpretation of results for various surgical methods. The most practical measure of success is the control of symptoms, although this can be at odds with anatomic outcome—the Lacrimal Paradox. Two patients presented, in 1994, with various symptoms at perplexing variance with the clinical signs—this leading to the evolution of a much greater understanding of the nature of lacrimal drainage dynamics. An elderly woman returned to the clinic after dacryocystorhinostomy (DCR), delighted with the results of surgery and, in her view, cured. I noted at examination, however, that she had an increased tear line on the operated side and found that she had medial common canalicular block. That is, surgery was an anatomic failure, but the patient viewed it as a success. Another woman attended the clinic 4 weeks after surgery, describing her DCR as a “complete disaster.” The surgical anastomosis was open to spontaneous fluorescein clearance, and she was reassured that conductance would increase as postoperative edema around the canaliculi settled; a few months later, she was asymptomatic. That is, surgery was an anatomic and physiological success, but the patient viewed it as a failure. This apparent paradox—of two patients with views opposite to anatomic outcome—is solvable only when drainage dynamics are considered as a 3-compartment model, with this hydraulic model reconciling the Lacrimal Paradox by allowing a dichotomy of symptoms in either “volume” symptoms or “flow” symptoms. Lacrimal drainage hydraulics may be considered as a 3-compartment model—the tear lake (first compartment), the lacrimal sac (second compartment), and the nasal space (third compartment)—joined by two conduits of relatively high hydraulic resistance, the lacrimal canaliculi and the nasolacrimal duct (Fig. 1). This concept of drainage dynamics generates a natural dichotomy for lacrimal symptoms and signs (Table): 1) volume characteristics, caused by fluid within the second compartment (lacrimal sac) with backwash of such fluid in the first compartment (tear lake); and 2) flow characteristics, caused by the limits of hydraulic conductance through the high-resistance (low conductance) segments of the system—a group of symptoms and signs not dependent on the size of the second compartment. Herein lies the solution to the Lacrimal Paradox: The first patient (with symptomatic “success,” despite anatomic failure) originally had volume symptoms—with sticky eye and recurrent conjunctivitis—and these had been resolved by elimination of the lacrimal sac with DCR; although she had occluded canaliculi, tear production was insufficient to cause postoperative flow symptoms. The second patient (with symptomatic “failure,” despite anatomic success) had persistent flow symptoms caused by inadequate canalicular conductance, the latter improving with time, to render the patient asymptomatic. Appreciation of the 3-compartment model also allows a definition of the aims of lacrimal drainage surgery and sets clear standards for the functional outcome of such surgery. It is a popular belief that lacrimal drainage surgery creates a new conduit between the lacrimal sac and the nose, by external DCR, the endonasal route, or by reopening the nasolacrimal duct (with or without stenting). Techniques based on such ideas are liable to a relatively high failure rate (in the order of 30% to 50%) because of retention of the 3 compartments and persistent volume symptoms (Fig. 2A).

Intraconal implants are well established in the treatment of anophthalmic sockets,^1-3 and complications include tissue breakdown over the implant. Anterior migration of the implant because of tissue restitution during healing—termed the cactus syndrome by one of us (G.E.R.)—leads to a thinning of surface tissues (Figure 1A), with delayed exposure (Figure 1B) and, later, a frank extrusion (Figure 1G and H) of the implant. Small areas of implant exposure are more common than full extrusion,^1,4-6 although many techniques have been devised to prevent or treat implant exposure.^7-11