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he was known to suffer from pxf and had undergone standard uneventful phacoemulsification with in - the - bag implantation of monofocal iol in both eyes . in the right eye ,
a single piece poly ( methyl methacrylate ) ( pmma ) iol ( + 19 d ) and in the left eye , a single piece acrylic foldable iol ( + 19 d ) were implanted .
the surgeries were performed in the right and left eye at 9 and 8 years , respectively , before to this examination .
all the previous dilated annual eye examinations had been normal , with no clinical evidence of iol subluxation . on clinical examination ,
his visual acuity was 20/60 in both the eyes . slit lamp examination revealed anterior partial in - the - bag iol dislocation [ figs . 1 and 2 ] , capsular contraction and deformation of iol haptics .
intraocular pressure by goldmann applanation tonometer ( gat ) was 19 mmhg in both eyes .
pupils were dilated with 2.5% phenylephrine eye drops . indirect ophthalmoscopy revealed normal ocular fundi .
constriction of pupils and iol repositioning was tried by instillation of 2.0% pilocarpine eye drops in the supine position , but the procedure was unsuccessful . the next day , iol along with the capsular bag were explanted surgically , [ fig . 3 ] and
secondary scleral suture fixation of single piece pmma iol ( auro india ) was done in the same sitting for the right eye .
after 12 months of surgery , best corrected visual acuity was 20/30 in both eyes .
the manifest refraction was 1.00 dc  180 and + 1.00 ds/1.50 dc 180 in the right and left eye , respectively .
the eyes were quiet and iop was 19 mmhg ( gat ) in both eyes .
anteriorly dislocated in - the - bag acrylic foldable intraocular lens with ( a ) capsular contraction and ( b ) compressed haptic in - the - bag modified c loop poly ( methyl methacrylate ) intraocular lens with ( a ) ring of soemmering and ( b ) compressed haptic explanted intraocular lens with the capsular bag
iol dislocation may occur in the immediate postoperative period and is mainly due to poor iol fixation .
other predisposing factors are prior vitrectomy surgery , trauma , high myopia , retinitis pigmentosa and connective tissue disorders such as marfan syndrome , homocystinuria , hyperlysinemia , scleroderma , weill 
the late dislocation of iol may occur anytime from 1 month to 8 years following surgery .
bilateral spontaneous in - the - bag iol dislocations were reported in the anterior or posterior chamber in two cases of gyrate atrophy , one case of retinitis pigmentosa , and in one patient with intermediate uveitis .
a literature search revealed only one case report of bilateral spontaneous anterior partial in - the - bag iol dislocation in a patient with pxf .
various corrective surgical management approaches to dislocated iol including iol exchange or iol repositioning with scleral or iris fixation have been described .
apart from the more commonly used suture fixation , a sutureless , glued iol technique has also been described in a case of bilateral , anterior , in - the - bag subluxation of iol in a patient with retinitis pigmentosa .
as all the mentioned surgical procedures are reported to be equally efficacious , the ultimate choice of surgery depends on the surgeons preference and experience .
bilateral anterior partial in - the - bag iol dislocation occurred spontaneously 9 years after cataract surgery .
iol haptics were found to be compressed either due to loss of biomechanical memory or due to contraction of the capsule . except pseudophakia , during all previous eye examinations , no other signs indicative of future risk of iol dislocation were observed .
the present method of management of iol exchange , limited anterior vitrectomy , and scleral suture fixation of iol was found to be a safe and effective surgical option in such a case .
it is also observed that iol design and biomaterial had no role in the prevention of spontaneous dislocation of iol .
we believe pxf , myopia , and capsular contraction together were responsible for spontaneous dislocation of the iols , and it is only the second such case report in literature .
such dislocations can be managed definitively by iol exchange and scleral suture fixation and limited anterior vitrectomy .
we report a rare case of bilateral spontaneous anterior partial in - the - bag intraocular lens ( iol ) dislocation in a 75-year - old man with pseudoexfoliation ( pxf ) . 
 he underwent uneventful phacoemulsification in both eyes with in - the - bag iol implantation 9 years back . in the right eye , single piece poly ( methyl methacrylate ) ( pmma ) 
 iol ( + 19 d ) and in the left eye , single piece acrylic foldable iol ( + 19 d ) were implanted . 
 an attempt at pharmacological iol repositioning was unsuccessful . 
 the dislocated iols were explanted and exchanged with scleral suture fixated pmma iols . 
 vision improved to 20/30 in both eyes following surgery , without any associated ocular morbidity . 
 we believe that zonular weakness secondary to pxf , capsular contraction , and myopia together were the predisposing factors for partial anterior dislocation of iols and iol exchange with scleral suture fixation of iol is a safe and effective treatment option .