Capsular block syndrome in the late postoperative period of cataract surgery

Purpose. To identify the features of pathogenesis and evaluate the results of laser and surgical treatment of patients with capsule block syndrome (CBS) in the late postoperative period. Material and methods. This study included 13 patients (13 eyes) aged from 26 to 86 years with a diagnosis of CBS in the late postoperative period. In addition to the standard ophthalmological examination, patients underwent optical coherence tomography of the anterior segment, biometry, and ultrasound biomicroscopy. For treatment, Nd:YAG laser or surgical intervention (washing out the lens masses) was used. Results. In the study group CBS developed in the period from 6 to 13 years after cataract surgery. According to slitlamp biomicroscopy, various contents of the retrooptic space were observed. Using ultrasound biomicroscopy, the presence of Soemmering’s ring was detected in 11 patients, and in all patients the site of a breakthrough in the capsular barrier, partial destruction of Soemmering’s ring and the release of its contents into the capsular bag was visualized. One case of self-resolution of the syndrome was observed; in the rest, laser (6 eyes) and surgical (6 eyes) treatment was used. Visual acuity after treatment increased in all patients. Conclusion. CBS is variable in its manifestation — from the transparent contents of the retrooptic space to the accumulation of dense swelling lenticular masses in it. Optical coherence tomography of the anterior segment and ultrasound biomicroscopy are the main complementary methods for CBS diagnosing. The pathogenesis of CBS is associated with the formation and progression of Soemmering’s ring, breakthrough of the capsular barrier and the release of lens masses into the retro-optic space. Laser and surgical techniques are effective in treating CBS. Key words: capsular block syndrome, capsular bag distention syndrome, posterior capsule opacification, Soemmering ring, ultrasound biomicroscopy