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descemet s membrane tearing is often attributable to surgical procedures , and is usually confined to the incision site . early in the postoperative period , patients can be asymptomatic , and clinical signs might be difficult to detect .
when apparent , descemet s membrane tears and detachments may cause decreased vision and corneal edema in the first days or weeks after surgery .
few cases of descemet s detachments occurring late in the postoperative period have been reported , and very rarely months after surgery .
wong et al reported a case of a patient who developed a descemet s detachment 8 months after thc : yag ( thulium , holmium , chromium - doped yttrium aluminum garnet crystal ) laser sclerostomy.1 stewart et al reported a case of a descemet s detachment that occurred 5 months after uncomplicated cataract surgery.2 to our knowledge , this is the first report of delayed descemet s tear and detachment occurring 11 months after cataract surgery .
a 51-year - old hispanic male was referred to the bascom palmer eye institute cornea service with a complaint of sudden onset of blurred vision in the left eye 3 weeks prior .
he had undergone uncomplicated phacoemulsification ( alcon ) with posterior chamber intraocular lens insertion 11 months prior in the left eye and 5 years prior in the right eye .
he had been using topical prednisolone acetate 1% and sodium chloride 5% for 3 weeks with no improvement in his symptoms .
the exam revealed best - corrected visual acuity of 20/20 in the right eye and 20/40 in the left eye , with a 2.50 sphere at 61. intraocular pressures were 10 mmhg in both eyes by tono - pen .
slit - lamp exam ( zeiss ) of the left eye revealed a healed temporal corneal incision wound and abnormal descemet s membrane wrinkling with irregular edges .
stromal edema was noted just nasally to this site , which extended centrally through the visual axis ( figure 1 ) .
the view of the fundus was hazy in the left eye , but both retinas appeared flat and without lesions , and the optic nerves were unremarkable ( topcon indirect ophthalmoscope ; alcon ma60 posterior chamber lens ) .
orbscan pachymetry revealed central corneal thickness of 614 m in the right eye and 878 m in the left eye ( 1,093 m temporally , 702 m nasally ) .
topcon keratometry readings of the left eye revealed 2.5 d of astigmatism at 61. specular endothelial
microscopy and cell count showed no significant difference between the two eyes ( 2,427 cells / mm oculus dexter , 2,320 cells / mm oculus sinister ; topcon ) .
the patient was diagnosed with a spontaneous descemet s dehiscence at the site of the clear cornea cataract incision .
as the corneal edema was mild , medical treatment was continued with hyperosmotic saline ointment at bedtime , hyperosmotic drops in the morning , timolol 0.5% daily , and tapering off the prednisolone .
he was also instructed to use a hair dryer to the eye in the morning , avoid eye rubbing , and use a protective shield at bedtime . in the subsequent months of follow - up
, the corneal edema and visual acuity remained the same . at 7 months after our initial evaluation , the patient reported decreased vision in the left eye associated with pain .
the exam revealed a best - corrected visual acuity of 20/200 in the left eye , intraocular pressure of 18 mmhg , and microcystic corneal edema extending from the site of the descemet s tear ( figure 2 ) .
a low - lying descemet s detachment could not be ruled out , so surgical intervention with 0.25 ml of 100% sulfur hexafluoride gas injection was elected .
one month after the intracameral gas injection , the vision remained at 20/200 and there was no improvement in the corneal edema . penetrating keratoplasty  the best surgical option at that time since descemet s stripping endothelial keratoplasty was not available 
was discussed with the patient , but he decided to continue medical therapy and observation .
four months later , he presented with vision of 20/400 in the left eye , persistent corneal edema , and descemet s disruption
the remainder of descemet s membrane was partially detached from the corneal stroma ( figure 3 ) .
ten years after surgery , the best - corrected visual acuity in the left eye was 20/25 , and the graft remained clear .
we report a case of delayed descemet s membrane detachment and tear leading to hydrops 11 months after uncomplicated phacoemulsification using a temporal clear cornea approach .
the proximity of the edema to the corneal wound suggests this as the source , despite the fact that the wound had been made 11 months prior , appeared well healed , and had been asymptomatic until 3 weeks prior . known risk factors that may increase the likelihood of traumatic entry into the anterior chamber include oblique angle of entry , anterior and shelved incisions , use of a blunt knife , injection of viscoelastic or antibiotics anteriorly to descemet s membrane , a shallow anterior chamber , soft eye , previous surgery , and recent episode of corneal edema.35 the location of the incision may have contributed to the development of the descemet s membrane tear in this patient .
we noted an anterior temporal corneal entry incision wound to the anterior chamber , leading to a descemet s membrane prone to detachment and tear after phacoemulsification .
kansal and sugar explored the possibility of an underlying anatomic predisposition for the development of descemet s membrane detachment after phacoemulsification , possibly explained by an abnormality in the fibrillary stromal adhesion to descemet s membrane.6 some patients may have an abnormal attachment between the stroma and descemet s membrane caused by dysfunction of the anchoring protein ig - h3.7,8 the predisposition is more evident in cases of bilateral descemet s membrane detachment after cataract surgery9 and among siblings.10 many mechanisms have been easily attributable to the occurrence of early detachments after cataract surgery .
however , the scarce literature on the very few late presentations does not methodically discuss mechanisms responsible for delayed cases , especially when they present with tears .
a logical explanation for this unusually late presentation is that he might have traumatized his cornea , eg , by eye rubbing or unnoticed trauma , to a point that he caused further disruption of an already - susceptible descemet s membrane and acute onset of edema in this area . in patients with keratoconus ,
the central corneal thickness in the right eye appeared relatively high at the time of presentation .
however , based on previous readings from the patient , we considered the pachymetry results to be symmetrically conserved , except for the area of edema in the left eye , which was thicker .
interestingly , preexistent endothelial dysfunction has been reported as the only significant preoperative risk factor by ti et al.11 the endothelium in both eyes appeared to be normal by specular microscopy , excluding endothelial dysfunction and pseudophakic bullous keratopathy as the cause of hydrops .
it is important to be aware of the potential causes of corneal edema months after cataract surgery , in order that they may be diagnosed and treated appropriately . instructing patients to avoid eye rubbing or any other type of trauma to the cornea
a 51-year - old male who had undergone phacoemulsification in his left eye 11 months prior presented with complaint of sudden onset of blurred vision in the same eye . 
 review of his clinical course , slit - lamp exam , pachymetry , and specular endothelial microscopy led to the diagnosis of acute hydrops caused by descemet s membrane dehiscence at the site of the incision . 
 he was initially managed with medical treatment and observation . in the subsequent months of follow - up , 
 the corneal edema and the patient s visual acuity did not improve . 
 intracameral gas injection was performed 7 months after presentation , but because of persistent corneal edema and nonattached descemet s membrane , penetrating keratoplasty was performed . 
 histopathologic examination confirmed the diagnosis . the patient has had a clear corneal graft since then . although descemet s membrane detachment is a rather common complication after intraocular surgery , its unusually delayed presentation can also occur , and 
 should not be confused with pseudophakic bullous keratopathy . 
 many mechanisms have been studied for the development of early tears and detachments after cataract surgery , but little is known about late presentations . 
 the authors explore possible causes , and highlight the importance of instructing patients to avoid eye rubbing and any other type of trauma to the cornea after intraocular surgery .