Diagnostic vitrectomy in intermediate uveitis

Vitreous fluid biomarkers

Interactions between cells and the network of secreted proteins are associated with the ocular disease. In most cases, clinical appearcance is sufficiently diagnostic. However, in cases of nonspecific or atypical clinical presentation, diagnostic sampling of vitreous fluid can aid diagnosis and treatment for ocular disease. Progresses in the basic sciences, particularly molecular biology, and advances in surgical instrumentation have greatly enhanced the diagnostic armamentarium. These developments also have led to a better understanding of the pathophysiological processes involved in ocular diseases and have prompted evolution of new therapeutic modalities. In this chapter, we review techniques for vitreous fluid sampling and biomarker quantitation thereof. The molecular biology of bioactive vitreous fluid factors is also discussed with respect to their clinical involvement in the development of ocular disease.

The diagnostic yield of vitrectomy specimen analysis in chronic idiopathic endogenous uveitis

PURPOSE

The low diagnostic yield of vitrectomy specimen analysis in chronic idiopathic uveitis (CIU) has been related to the complex nature of the underlying disease and to methodologic and tissue immanent factors in older studies. In an attempt to evaluate the impact of recently acquired analytic methods, the authors assessed the current diagnostic yield in CIU.

METHODS

Retrospective analysis of consecutive vitrectomy specimens from patients with chronic endogenous uveitis (n = 56) in whom extensive systemic workup had not revealed a specific diagnosis (idiopathic) and medical treatment had not resulted in a satisfying clinical situation. Patients with acute postoperative endophthalmitis served a basis for methodologic comparison (Group 2; n = 21).

RESULTS

In CIU, a specific diagnosis provided in 17.9% and a specific diagnosis excluded in 21.4%. In 60.7% the laboratory investigations were inconclusive. In postoperative endophthalmitis, microbiological culture established the infectious agent in 47.6%. In six of eight randomly selected cases, eubacterial PCR identified bacterial DNA confirming the culture results in three, remaining negative in two with a positive culture and being positive in three no growth specimens. A double negative result never occurred, suggesting a very high detection rate, when both tests were applied.

CONCLUSIONS

The diagnostic yield of vitrectomy specimen analysis has not been improved by currently routinely applied methods in recent years in contrast to the significantly improved sensitivity of combined standardized culture and PCR analysis in endophthalmitis. Consequently, the low diagnostic yield in CIU has to be attributed to insufficient understanding of the underlying pathophysiologic mechanisms.

Diagnostic yield of vitrectomy in eyes with suspected posterior segment infection or malignancy

PURPOSE

To determine the yield of diagnostic pars plana vitrectomy in eyes with suspected posterior segment inflammation or malignancy when clinical examination and systemic laboratory testing did not yield a specific diagnosis.

DESIGN

Non-comparative interventional case series

PARTICIPANTS

Eighty-seven consecutive patients (90 eyes) who underwent diagnostic pars plana vitrectomy from 1989 through 1999.

INTERVENTIONS

Vitreous samples were analyzed in a directed manner based on the preoperative clinical examination and systemic laboratory testing.

MAIN OUTCOME MEASURES

Diagnosis from each test performed on the vitreous samples.

RESULTS

Diagnostic vitrectomy was performed alone in 6 eyes (7%) and as part of a therapeutic procedure in the remaining 84 eyes. The diagnostic tests performed most frequently included cytopathology (83%), microbiologic culture and sensitivity (43%), polymerase chain reaction (PCR) (36%), and intraocular antibody levels for T. canis (14%). Of these, intraocular antibody testing and PCR had the highest positive yield, 46% and 39%, respectively. Overall, directed vitreous analysis identified a specific cause in 35 eyes (39%). Of the 65 cases in which an underlying infection was suspected preoperatively, the procedure yielded a specific diagnosis in 27 (42%). When intraocular malignancy was considered preoperatively (71 eyes), a diagnosis of intraocular lymphoma was obtained in seven (10%). This difference between these diagnostic yields was significant (P = 0.02, Fisher's exact test).

CONCLUSIONS

Diagnostic vitrectomy with directed vitreous fluid analysis yields a specific cause and guides subsequent therapy in a high percentage of cases. This procedure is a valuable adjunct in cases that cannot be diagnosed by less invasive methods.

Vitrectomy in the management of uveitis

OBJECTIVE

To review the indications for vitrectomy in uveitis cases.

PATIENTS AND METHODS

Charts of patients seen at the uveitis clinic of the Jules Gonin Eye Hospital from January 1993 to August 1998 and who had undergone vitrectomy were reviewed. Patients with infectious uveitis occurring within three months after intraocular cataract surgery were excluded. The types of uveitis were recorded and indications for vitrectomy were analyzed.

RESULTS

A total of 630 patients were examined at the uveitis clinic. Fifty-one of these patients (51 eyes, 8.1%) were referred for vitrectomy and were included in this study. Vitrectomy was performed for three reasons: 1) to treat the complications of uveitis (90%), including vitreous opacification in 35 eyes (69%), retinal detachment in seven eyes (14%), epimacular membrane in seven eyes (14%), and dense opacification of the posterior capsule after cataract surgery in six eyes (12%)(the mean delay between uveitis and vitrectomy in this group was 8.4 years); 2) for diagnostic purposes in 19 eyes (37%); and 3) to remove confined infectious foci in 16 eyes (31%) and allow a thorough intraocular distribution of antibiotics. Visual acuity improved in 41 patients (80.4%), remained unchanged in three (5.8%), and decreased in seven (13.7%) because of secondary or persistent retinal detachment or cystoid macular edema.

CONCLUSION

Vitrectomy was indicated to treat the complications of uveitis, to provide vitreous for diagnostic purposes, and to allow a better diffusion of intraocular antibiotics. Long-standing uveitis did not seem to be influenced by vitrectomy.

Ocular non-Hodgkin's lymphoma: a clinical study of nine cases

BACKGROUND

Primary oculocerebral large cell malignant non-Hodgkin's lymphoma, formerly called ocular reticulum cell sarcoma, runs a uniformly fatal course. Once the central nervous system (CNS) is involved, survival without treatment is very limited. Although treatment does not substantially improve the long term survival, it provides short term improvement in these patients.

METHODS

The charts of all patients with ocular involvement of non-Hodgkin's lymphoma followed during the period 1984-93 were reviewed. The diagnosis of non-Hodgkin's lymphoma was made by different diagnostic approaches: CNS biopsy, anterior chamber tap, vitrectomy, haematology, and necropsy.

RESULTS

Eight patients had oculocerebral large cell and one had small cell non-Hodgkin's lymphoma. Five patients with pure ocular localisation had initially received steroid treatment for intermediate uveitis. First diagnosis was made on CNS biopsy in three, anterior chamber tap in one, vitreous aspirate in three, haematology in one, and necropsy in one case.

CONCLUSION

Ocular non-Hodgkin's lymphoma is a difficult diagnosis. Vitrectomy allows cytological diagnosis in most but not all cases. When no treatment is given, patients survive for only a few weeks once the CNS is involved. Although the disease is eventually fatal, treatment by means of radiotherapy, steroid administration, and vitrectomy can allow these patients to lead a normal professional and social life during the years between recurrences.

Diagnostic vitrectomy and chronic uveitis

BACKGROUND

From the introduction of vitrectomy, infectious endophthalmitis was one of the indications for this surgical technique. Vitrectomy was later found to be a valuable method in both diagnostic and therapeutic evaluation of chronic uveitis.

METHODS

Twenty-eight eyes of 25 patients were operated on with purely diagnostic intent. These were patients not responding, or no longer responding, to their cortisone treatment and for whom no etiology had been found previously.

RESULTS

Vitrectomy itself yielded the diagnosis in nine eyes of eight patients. Three had unexpected infectious pathology (one bacterial, one mycotic, one viral), while five had tumoral pathology four with non-Hodgkin lymphoma and one with a metastasis of a malignant melanoma of the skin. In four other patients, typical fundus lesions were seen during the surgery, providing a clue to the etiology: three cases of retinal necrosis and one case of a pseudotumoral mass suggestive of Toxocara canis. Serologic tests confirmed three cases of herpes simplex infection and one of Toxocara canis. Apart from the fact that a diagnosis could be made in half of the patients, the diagnostic vitrectomy also had a favorable effect upon vision in half the cases.

CONCLUSION

In cases of chronic uveitis where no etiology has been found, vitrectomy is able to provide a diagnosis in about one-third of eyes directly. During surgery a typical appearance of the fundus may reveal a supplementary diagnosis, resulting in an overall diagnosis in about half of the cases. Moreover, half of the patients will have improved vision after surgery.