Risk Factors for Tube Shunt Exposure: A Matched Case-Control Study

Abstract

Purpose. To evaluate potential risk factors for developing tube shunt exposure in glaucoma patients. Patients and Methods. Forty-one cases from 41 patients that had tube shunt exposure from 1996 to 2005 were identified from the Robert Cizik Eye Clinic and Bascom Palmer Eye Institute. Each case was matched with 2 controls of the same gender and with tube shunts implanted within 6 months of the index case. Conditional logistic regression was used to determine risk factors. Results. The study cohort includes a total of 121 eyes from 121 patients. The mean age was 63.6 ± 19.7 years, ranging from 1 to 96 years. The average time to exposure was 19.29 ± 23.75 months (range 0.36–85.74 months). Risk factors associated with tube exposure were Hispanic ethnicity (P = 0.0115; OR = 3.6; 95% CI, 1.3–9.7), neovascular glaucoma (P = 0.0064; OR = 28.5; 95% CI, 2.6–316.9), previous trabeculectomy (P = 0.0070; OR = 5.3; 95% CI, 1.6–17.7), and combined surgery (P = 0.0381; OR = 3.7; 95% CI, 1.1–12.7). Conclusions. Hispanic ethnicity, neovascular glaucoma, previous trabeculectomy, and combined surgery were identified as potential risk factors for tube shunt exposure. These potential risk factors should be considered when determining the indication for performing tube shunt implantation and the frequency of long-term followup.

Explantation of the Novel Ahmed Glaucoma Valve M4 Implant

“…In prior studies, risk factors for tube exposure included Hispanic ethnicity, NVG, prior trabeculectomy, multiple prior intraocular surgeries, and inferiorly placed implants. [12][13][14] In both plate exposures in this study, the exposures occurred at the anterior corner of the plate, which is rigid with a moderately sharp edge (Fig. 2).…”

Postoperative Complications in the Ahmed Baerveldt Comparison Study During Five Years of Follow-up

“…19 Previously identified risk factors for erosion include prior ocular surgery, neovascular glaucoma, Hispanic ancestry, and combining GDI with another surgery. 25,26 The mechanism for tube erosion has been postulated to be either mechanical or immunological. 27,28 Unproven strategies for reducing the risk of tube erosion include routing the tube directly superiorly to reduce rubbing by the eyelid margin, placing the tube in the sulcus when possible, or tunneling the tube and also covering it with a tissue patch graft.…”

Glaucoma Drainage Devices: Risk of Exposure and Infection

“…A matched case-control study by Koval et al 14 found Hispanic ethnicity, neovascular glaucoma, prior trabeculectomy, and combined surgical procedures to be significantly associated with tube exposure. Byun et al 15 reported a higher number of previous ocular surgeries to be a risk factor for exposure.…”