The Results of B-scan Ultrasonography in Different Positions after Vitrectomy and Gas Tamponade

PURPOSE To determine the proper time frame in which to assess retinal attachment status and to evaluate the superior retinal attachment status by performing B-scan ultrasonography in different positions on patients who have undergone pars plana vitrectomy and gas tamoponade. METHODS In this prospective study, 23 patients (23 eyes) who had undergone pars plana vitrectomy and gas tamponade were investigated between June 2005 and February 2006. SF(6) (18%) was injected into the vitreous cavity of 15 eyes, and C(3)F(8) (14%) was injected into the vitreous cavity of 8 eyes. At postoperative day 1, day 3, week 1, week 2, and week 4, B-scan ultrasonography was performed in the supine, sitting, prone, right decubitus, and left decubitus positions. RESULTS The proper time to evaluate the retinal attachment status was three days post-operatively in 10 eyes (66.7%) with SF(6) (18%) injections and two weeks post-operatively in six eyes (75%) that had C(3)F(8) (14%) injections. The superior retinal attachment status can be evaluated from the summation of B-scan ultrasonography results performed in the right decubitus and left ducubitus positions. CONCLUSIONS The proper time to evaluate the retinal attachment status was related to the degree of the gas absorption when performing B-scan ultrasonography after pars plana vitrectomy and gas tamponade. To evaluate the entire retina, it is useful to perform B-scan ultrasonograhy in the prone, right decubitus and left decubitus positions.