Investigating a possible cause of the myopic shift after combined cataract extraction, intraocular lens implantation, and vitrectomy for treatment of a macular hole.
OBJECTIVE
It has been documented that combination surgery (phacoemulsification, intraocular lens implantation, and vitrectomy) produces a postoperative myopic shift. We hypothesize that the myopic shift seen in patients treated with combination surgery, membrane stripping, and injection of C3F8 for treatment of a macular hole is due to an erroneously short preoperative axial length measurement by the IOLMaster.


METHODS
Retrospective chart review.


METHODS
Eleven eyes of 10 patients treated for a stage III or IV macular hole were recruited from a database search of 1 vitreoretinal practice in Regina, Sask.


METHODS
All eyes included in the study underwent combination surgery, membrane stripping, and injection of C3F8. None of the patients demonstrated concurrent eye pathology. Postoperative axial length measurements by the IOLMaster were obtained and compared with the same preoperative measurements.


RESULTS
The mean (SD) postoperative myopic shift seen in the study eyes was -0.76 (0.65) D (z = -2.578, p < 0.01). The mean (SD) preoperative and postoperative axial length measurements were 23.54 (1.02) mm and 23.53 (1.01) mm, respectively. No significant difference in axial length was found between the preoperative and postoperative axial length measurements (t = 0.43, df = 10, p = 0.68).


CONCLUSIONS
These findings do not support our hypothesis of an erroneous preoperative axial length measurement by the IOLMaster in patients with a stage III or IV macular hole treated with combination surgery, membrane stripping, and injection of C3F8. Further studies are required to determine the precise cause of the postoperative myopic shift.
Pasqua Hospital Eye Centre, University of Saskatchewan, Regina, Sask.
David
D
Ehmann
Raúl
R
García
D001485:Basement Membrane / Q000601:surgery; D005123:Eye / Q000473:pathology; D005466:Fluorocarbons / Q000008:administration & dosage; D006801:Humans; D019654:Lens Implantation, Intraocular; D009216:Myopia / Q000209:etiology* / Q000503:physiopathology*; D018918:Phacoemulsification; D011183:Postoperative Complications; D012167:Retinal Perforations / Q000601:surgery*; D012189:Retrospective Studies; D014821:Vitrectomy
D005466:Fluorocarbons; C042852:perflutren