Ultrasound biomicroscopic quantification of the change in anterior chamber angle following laser peripheral iridotomy in early chronic primary angle closure glaucoma

AIMS: To prospectively evaluate by ultrasound biomicroscopy (UBM) and gonioscopy the anterior chamber angle widening following laser peripheral iridotomy (LPI) in eyes with early chronic primary angle closure glaucoma (CACG). METHODS: A total of 55 eyes of 55 patients with CACG presenting with less than 180 degrees peripheral anterior synechiae (PAS) were enrolled in the study. Angles were assessed by gonioscopy (Shaffer's grading) and UBM, before and 4 weeks after LPI. The angle opening distance at 250 and 500 microm from the scleral spur (AOD 250 and AOD 500) was computed. Results were analysed using the Wilcoxon signed-rank test. RESULTS: In the quadrant with LPI, the mean gonioscopy grade increased significantly from 0.45 to 1.45 (P<0.001) and the mean AOD 250 and AOD 500 increased from 38.5+/-25.9 to 83.5+/-48.4 microm (P<0.001) and 110.2+/-80.9 to 170.6+/-83.4 microm (P<0.001), respectively. The angles widened significantly in the opposite quadrant on UBM (AOD 250: 48.8+/-31.5-82.7+/-43.9 microm, P<0.001; AOD 500:117.2+/-65.5-172.2+/-81.7 microm; P<0.001), but the median gonioscopy grade remained unchanged. CONCLUSIONS: LPI significantly widened the anterior chamber angle in the quadrant with LPI and the quadrant furthest away in patients of CACG with established glaucomatous damage. This change was much better appreciated by the UBM than gonioscopy.     

The effect of different doses of ketamine on intraocular pressure in anesthetized children

BACKGROUND: When used for induction of anesthesia, ketamine usually increases intraocular pressure (IOP). However, the effect of low doses of ketamine, which are used for parental separation in children, is unknown. We studied the effect of two different doses of ketamine on IOP in anesthetized children. METHODS: Forty children age 1 to 6 years who met American Society of Anesthesiologists physical status I criteria scheduled to undergo surgery were randomly selected to receive either an induction dose (6 mg/kg) or a low dose (3 mg/kg) of ketamine intramuscularly. Anesthesia was induced and maintained with halothane, and ketamine was injected 10 minutes after induction. Intraocular pressure was measured using a Perkins applanation tonometer before ketamine administration and every 5 minutes thereafter for 20 minutes by an observer who was unaware of the ketamine dose used. 10.8 +/- 2.2 mm Hg to 12.6 +/- 2.8 mm Hg at 5 minutes and 11.9 +/- 2.5 mm Hg at 10 minutes after administration of ketamine in the induction-dose group. There was no significant change in IOP after administration of ketamine in the low-dose group. Intraocular pressure was significantly higher in the induction-dose group compared to the low-dose group at 5 minutes after administration of ketamine. More patients in the induction-dose group had postoperative airway obstruction and sedation than in the low-dose group. CONCLUSIONS: In children anesthetized with halothane, ketamine had a dose-dependent effect on IOP, with 6 mg/kg of the drug causing a small increase in IOP at 5 to 10 minutes and 3 mg/kg not altering the IOP. The higher dose of ketamine also was associated with an increased incidence of postoperative complications.     

Post penetrating keratoplasty glaucoma: Cumulative effect of quantifiable risk factors

Purpose:

To ascertain the incidence, identify risk factors and calculate cumulative effect of risk factors in patients developing glaucoma following optical penetrating keratoplasty.

Materials and Methods:

We carried out retrospective analysis of 445 patients, those underwent optical PK and had a minimum follow up of 6 m. Data on post-operative intra-ocular pressure (IOP) recorded at 3, 6, 9, 12 and 18 m or more was analyzed. Various risk factors including age, sex, indications for penetrating keratoplasty, pre-existing glaucoma and type of surgical procedures performed were analyzed by using univariate analysis and logistic regression technique.

Results:

Ninety (21%) of eyes developed post-PK glaucoma. On applying logistic regression, age, sex, indication of surgery, pre-existing glaucoma were found to be significant risk factors for the development of post-PK glaucoma (P < 0.05). Using logistic regression equation the cumulative risk of developing post-PK glaucoma in an individual patient can be calculated.

Conclusions:

Male patients, aged more than 40 years, having opaque grafts as an indication and with pre-existing glaucoma were found to be higher risk of developing post-PK glaucoma. Patients at higher cumulative risk for development of post-PK glaucoma may be closely monitored during follow-up.     

Insertion of laryngeal mask airway does not increase the intraocular pressure in children with glaucoma

Objectives:  It is hypothesized that in children with glaucoma, the insertion of laryngeal mask airway (LMA) will cause lesser rise in intraocular pressure (IOP) than tracheal tube (TT). Aim:  To compare the IOP response to LMA and TT insertion in children with glaucoma. Methods/Materials:  A prospective, randomized, single‐blind study was conducted in 30 glaucomatous ASA‐1 children, aged 1–10 years scheduled to undergo trabeculectomy. Anesthesia was induced with halothane and maintained for 5 min with 1 MAC of halothane after administering atracurium 0.5 mg·kg^?1 following which LMA or TT was introduced. IOP was measured in both the eyes before and after insertion of airway device for 5 min. Results:  The IOP increased significantly from 27.3 ± 5.2 to 31.2 ± 5.4 mmHg (P < 0.001) after tracheal intubation but returned to baseline within 5 min. The IOP did not change from the baseline after insertion of LMA. The IOP was significantly higher in group TT compared to group LMA at 2 min (P = 0.004) and 5 min (P = 0.01) after the device insertion. The heart rate (HR) increased significantly after tracheal intubation and returned to baseline 4 min after intubation. The HR increase was significantly more in TT group compared to LMA group at all times of observation. Both systolic blood pressure (SBP; P = 0.01) and diastolic blood pressure (DBP; P = 0.02) showed an increase at 1 min in children in group TT. Conclusion:  Insertion of LMA in glaucomatous children is not associated with an increased IOP response or cardiovascular changes.     

Comparison of clinical and cost‐effectiveness of psoralen + ultraviolet A versus psoralen + sunlight in the treatment of chronic plaque psoriasis in a developing economy

Psoralen + ultraviolet A (PUVA) therapy is an established modality for psoriasis. As India is a tropical country that has good availability of natural sunlight psoralen + sunlight (PUVAsol) may be a more convenient option. To compare the efficacy and cost‐effectiveness of PUVA versus PUVAsol in chronic plaque psoriasis. Cases of chronic plaque psoriasis with body surface area ≥10% or Psoriasis Area and Severity Index (PASI) ≥10, excluding erythrodermic or pustular psoriasis, were randomized to receive either PUVA or PUVAsol, with endpoint being the achievement of PASI 90 or completion of 12 weeks treatment, whichever is earlier. Cost analysis was also undertaken. Thirty‐six cases (16 in PUVA and 20 in PUVAsol group) completed treatment. In the PUVA group, 15 cases (93.75%) responded to therapy while in the PUVAsol group, 15 (75%) responded (P = 0.29). Mean baseline PASI in the PUVA and PUVAsol groups was 16 and 14.4, respectively, and at endpoint was 1.62 and 3.77. There was a significantly greater reduction in PASI in the PUVA group at 2 and 4 weeks but at 8 and 12 weeks and endpoint, it was comparable. Treatment failure occurred in 6.25% and 25% of cases respectively (P = 0.29). Side effects were higher with PUVA. Total cost of therapy was significantly higher in the PUVA group (P = 0.002). Cost‐effectiveness ratio was US$0.72 with PUVA and US$0.37 with PUVAsol. Both PUVA and PUVAsol were equally efficacious, with PUVAsol being twice as cost effective. Hence, PUVAsol may be recommended as treatment for psoriasis in a developing economy such as India.