Aetna considers Nd:YAG laser capsulotomy medically necessary when performed following cataract extraction (see CPB 0508 - Cataract Removal Surgery) in members with visually significant clouding (opacification) of the posterior portion of the membrane that surrounds the lens (the posterior capsule) according to the following selection criteria based on the clinical guidelines of an expert panel on cataract surgery convened by the Agency for Health Care Policy and Research (AHCPR, 1993):

1. After cataract removal in the same eye, unless the laser capsulotomy is scheduled at the same time as cataract removal surgery, or performed prophylactically.

2. When performed within 6 months of surgery only if one of the following medical necessity criteria is met:

   1. The member has a best-corrected visual acuity (BCVA) of 20/50 or worse and both of the following conditions are met:

      1. The eye examination confirms that posterior capsular opacification is present; and

      2. The visual impairment has interfered with the member's ability to carry out needed or desired activities; or

   2. The member has a BCVA of 20/40 or better and all of the following conditions are met:

      1. The eye examination confirms that posterior capsular opacification is present; and
      2. Visual disability fluctuates as a result of symptoms of glare or symptoms of decreased contrast; and

      3. Visual disability has interfered with the member's ability to carry out needed or desired activities; or

   3. When used for members with posterior capsular opacification regardless of functional impairment for any of the following reasons:

      1. To provide better visualization of the posterior pole for members with:

         1. Diabetic retinopathy; or
         2. Macular disease; or

         3. Retinal detachment; or

      2. To diagnose posterior pole tumors; or

      3. To evaluate the optic nerve head.

If none of the above criteria is met, Nd:YAG laser capsulotomy performed within 6 months of cataract surgery is considered experimental and investigational because of a lack of evidence of the value of routine prophylactic capsulotomy following cataract surgery.

Note: Because posterior capsular opacification is uncommon within 6 months after cataract surgery, requests for Nd:YAG laser capsulotomy performed within 6 months of cataract surgery of the same eye may be subject to medical necessity review.

Aetna considers Nd:YAG laser vitreolysis experimental and investigational for the treatment of vitreous degeneration and vitreous floaters because its effectiveness for these indications has not been established.

Aetna considers Nd:YAG laser anterior hyaloidotomy experimental and investigational for the treatment of trapped triamcinolone behind the lens after intra-vitreal injection because its effectiveness for this indication has not been established.

Aetna considers Nd:YAG laser peripheral iridotomy experimental and investigational for the prevention of pigment dispersion glaucoma because its effectiveness for this indication has not been established.

Aetna considers Nd:YAG laser posterior hyaloidotomy experimental and investigational for the clearance of pre-macular hemorrhages because its effectiveness for this indication has not been established.

The Agency for Health Care Policy and Research (AHCPR) panel concluded that laser capsulotomy should not be scheduled at the time cataract surgery is performed because one can not predict whether a cataract surgery patient will develop posterior capsular opacification or the time at which any such opacification will occur.  For similar reasons, manual removal of the posterior capsule, performed with a needle or hook (called corneo-scleral section), should not be routinely performed at the time of initial cataract surgery.

The AHCPR panel also concluded that neodymium:yttrium-aluminum-garnet (Nd:YAG) laser capsulotomy should not be performed prophylactically or scheduled routinely at particular times after cataract surgery.

The eye examination should confirm the diagnosis of posterior capsular opacification and exclude other ocular causes of functional impairment.  The panel concurred with the finding of the literature review that there is yet no objective method of relating the degree of capsular opacification to the severity of functional impairment.

The panel also concluded that posterior capsular opacification rarely occurs within 3 months of surgery, and that it is uncommon for posterior capsular opacification to occur within the first 6 months of surgery.  Therefore, any cases of Nd:YAG laser capsulotomy occurring within 6 months of cataract surgery should be reviewed, to ensure that Nd:YAG laser capsulotomy is reasonable and medically necessary.

In a single center retrospective study, Delaney and colleagues (2002) determined the effectiveness of Nd:YAG vitreolysis and pars plana vitrectomy in the treatment of vitreous floaters.  A total of 31 patients (42 eyes) who underwent 54 procedures (Nd:YAG vitreolysis or pars plana vitrectomy) for the treatment of vitreous floaters were included in the study.  Main outcome measures were percentage symptomatic improvement following treatment and incidence of post-operative complications.  Statistical analysis was performed using the Fisher exact test.  Posterior vitreous detachment was the primary cause of floaters in all 42 eyes with co-existing vitreous veils in 3 eyes and asteroid hyalosis in 2 eyes.  Thirty-nine of 42 eyes received Nd:YAG vitreolysis; 38 % found Nd:YAG vitreolysis moderately improved their symptoms while 62 % found no improvement.  After an average of 14.7 months follow-up, no post-operative complications were recorded.  Fifteen eyes underwent a pars plana vitrectomy, 1 with combined phaco-emulsification and posterior chamber implantation and 11 following unsuccessful laser vitreolysis.  Pars plana vitrectomy resulted in full resolution of symptoms in 93 % of eyes.  One patient developed a post-operative retinal detachment which was successfully treated.  The authors concluded that patients' symptoms from vitreous floaters are often under-estimated resulting in no intervention.  This paper showed Nd:YAG vitreolysis to be a safe but only moderately effective primary treatment conferring clinical benefit in 1/3 of patients.

Kirwan and Cahill (2011) reported on a case of successful drainage of a large pre-macular hemorrhage using laser photo-disruption of the posterior hyaloid membrane.  A 47-year old man presented acutely to the authors' emergency department complaining of a 24-hr history of sudden onset, painless and persistent loss of vision in his left eye.  Immediately before noticing this loss of vision, he had been vomiting violently from excessive alcohol intake.  The left visual acuity was counting fingers.  Dilated fundoscopy of the left eye revealed a large pre-macular hemorrhage that was 14 disc diameters in size.  Clotting investigations were normal.  A diagnosis of valsalva retinopathy was made and the patient elected to receive a prompt Nd:YAG laser posterior hyaloidotomy as an outpatient.  At 1 week follow-up, the hemorrhage had drained completely into the vitreous space revealing a healthy macula and the visual acuity had improved to 6/12 unaided.  At 6-month follow-up the left visual acuity stabilized at 6/9 unaided.  The authors concluded that Nd:YAG laser posterior hyaloidotomy is an useful outpatient procedure for successful clearance of large pre-macular hemorrhages that offers patients rapid recovery of visual acuity and the avoidance of more invasive intra-ocular surgery.  The findings of this case study (with short-term follow-up) needs to be validated by well-designed studies.

In a prospective, randomized, controlled trial, Scott et al (2011) tested the hypothesis that Nd:YAG laser peripheral iridotomy (LPI) significantly reduces the incidence of conversion from pigment dispersion syndrome (PDS) with ocular hypertension (OHT) to pigmentary glaucoma (PG).  A total of 116 eyes of 116 patients with PDS and OHT were used in this analysis.  Patients were assigned randomly either to Nd:YAG LPI or to a control group (no laser).  The primary outcome measure was conversion to PG within 3 years, based on full-threshold visual field (VF) analysis using the Ocular Hypertension Treatment Study criteria.  Secondary outcome measures were whether eyes required topical anti-glaucoma medications during the study period and the time to conversion or medication.  Fifty-seven patients were randomized to undergo laser treatment and 59 were randomized to no laser (controls).  Age, gender, spherical equivalent refraction, and intra-ocular pressure at baseline were similar between groups.  Outcome data were available for 105 (90 %) of recruited subjects, 52 in the laser treatment group and 53 in the no laser treatment group.  Patients were followed-up for a median of 35.9 months (range of 10 to 36 months) in the laser arm and 35.9 months (range of 1 to 36 months) in the control arm.  Eight eyes (15 %) in the laser group and 3 eyes (6 %) in the control group converted to glaucoma in the study period.  The proportion of eyes started on medical treatment was similar in the 2 groups: 8 eyes (15 %) in the laser group and 9 eyes (17 %) in the control group.  Survival analyses showed no evidence of any difference in time to VF progression or commencement of topical therapy between the 2 groups.  Cataract extraction was performed on 1 patient in the laser group and in 1 patient in the control group during the study period (laser eye at 18 months; control eye at 34 months).  The authors concluded that the findings of this study suggested that there was no benefit of Nd:YAG LPI in preventing progression from PDS with OHT to PG within 3 years of follow-up.

Ascaso and colleagues (2012) reported on the case of a 65-year old male who underwent intra-vitreal triamcinolone acetonide (IVTA) injection for treating a clinically significant macular edema (CSME) due to background diabetic retinopathy in his left eye.  On the first post-operative day, visual acuity dropped from 20/80 to hand movements.  Slit-lamp examination showed the drug between the posterior capsule of the lens and the anterior hyaloid face.  Two weeks later, visual acuity and the milky fluid seemed unchanged.  Neodymium:yttrium-aluminum-garnet laser anterior hyaloidotomy was performed.  One week later, slit-lamp examination of the retrolental space revealed the complete disappearance of triamcinolone and intra-ocular pressure remained stable.  After a follow-up period of 2 months, visual acuity increased to 20/50 with the lens remaining clear.  The authors concluded that Nd:YAG laser anterior hyaloidotomy is an effective, simple, useful and minimally invasive outpatient procedure in patients with persistent entrapment of triamcinolone behind the crystalline lens, allowing the drug to clear without trauma to the lens.  The findings of this case study (with short-term follow-up) needs to be validated by well-designed studies.