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Applications of the Guarded-Needle External Drainage Technique in Vitreoretinal Surgery
Tina Felfeli1,2, Parampal S Grewal3, Efrem D Mandelcorn1,4
1Department of Ophthalmology and Vision Sciences, University of Toronto, Toronto, Ontario, Canada.
Purpose:
To describe the surgical technique using the guarded-needle external drainage for a wide variety of applications in vitreoretinal surgery.
Methods:
A step-by-step procedure and a surgical video using the guarded-needle external drainage technique are presented. In addition, a series of representative cases with wide-ranging diagnoses who underwent the technique is reviewed.
Description And Technique:
The guarded-needle using a 27-gauge thin-walled TSK needle (TSK Laboratory International) and a trimmed 70 buckle sleeve are connected to the active extrusion tubing of the vitrectomy machine. External drainage is performed by actively aspirating subretinal fluid using low active vacuum. The guarded-needle external drainage technique is used in cases with bullous detachments, and small and anterior breaks, when performing scleral buckle, for prevention of underfill when using oil tamponade in cases with choroidal effusion, addressing subretinal gas/air, lysing a subretinal band, draining a suprachoroidal hemorrhage, for diabetic tractional retinal detachments, detachments with no definitive break, and subretinal biopsy in exudative detachments.
Conclusion:
The guarded-needle external drainage has a wide range of applications in vitreoretinal surgery.
