Short term surgical outcomes of modified deep sclerectomy with catgut implant

We compared the effectiveness of and complications resulting from modified deep sclerectomy with catgut implant (modified-DSCI) with those of standard deep sclerectomy with collagen implant (DSCI) in the short term following surgery. In this retrospective study, standard-DSCI was performed on thirteen patients (17 eyes), and modified-DSCI was performed on seven patients (11 eyes). After dissection of a 5x5 mm sized superficial scleral flap, a 3x4 mm sized rectangular deep scleral flap was constructed in DSCI and a 2x3 mm sized triangular deep scleral flap in modified DSCI. A collagen implant was placed on the scleral bed in DSCI and # 0 CHROMIC Catgut Absorbable Suture was used in modified DSCI. The mean follow up was 11.0+/-6.1 months in DSCI and 9.3+/-4.7 months in modified DSCI. The mean preoperative intraocular pressure (IOP) was 38.6+/-10.9 mmHg in DSCI and 34.8+/-8.6 mmHg in modified DSCI. In the DSCI group, the IOP was 13.4+/-3.0 mmHg at final follow up, and was 11.4+/-3.2 mmHg in the modified DSCI group. The number of Nd:YAG goniopuncture was 3 cases (25%) in the modified DSCI group, and 3 cases (21.4%) in the DSCI group. The number of intraoperative microperforations was 3 in the DSCI group and 2 in the modified DSCI group. Temporary hypotony was encountered in 8 eyes (57.1%) of the DSCI group and 4 eyes (50%) of the modified DSCI group. There was no significant difference observed between the two groups in regards to the effectiveness or rate of complications seen during short term follow up.

Increased frequencies of glutathione S-transferase (GSTM1 and GSTT1) gene deletions in Korean patients with acquired aplastic anemia

Patients with reduced ability to metabolize environmental carcinogens or toxins may be at risk of developing aplastic anemia. Glutathione S-transferase (GST) has been implicated in detoxifying mutagenic electrophilic compounds. This study asked whether the homozygous gene deletions of GSTM1 and GSTT1 affect the likelihood of developing aplastic anemia. The incidence of GSTM1 and GSTT1 gene deletions was significantly higher for aplastic anemia patients (odds ratio [OR]: 3.1, P =.01 and OR: 3.1, P =.004, respectively) than for healthy controls. Among the aplastic anemia patients, 17.5% (10:57) had chromosomal abnormalities at the time of diagnosis, and all aplastic anemia patients with chromosomal abnormalities showed GSTT1 gene deletions (P =.048). Individuals with GSTM1 and GSTT1 gene deletions may have greater susceptibility to aplastic anemia. It is possible that genetic instability or chromosomal damage due to abnormal detoxification of environmental toxins might have worked as an important pathophysiologic mechanism of aplastic anemia for patients with GSTT1 gene deletions.

Surgical outcomes of deep sclerectomy with collagen implant

We evaulated the effectiveness and adverse effects of deep sclerectomy with collagen implant (DSCI), which is a kind of nonpenetrating filtering surgery. In this retrospective study, DSCI was performed in 15 eyes of 11 glaucoma patients. An trabeculo-Descemet's membrane (TDM) window is created by a deep sclerokeratectomy, and the collagen implant is placed in the sclera bed under a superficial flap (deep sclerectomy with collagen implant). In 3 of 15 eyes the DSCI was intraoperatively converted to conventional filtering surgery for a large perforation of the TDM. These eyes were not included in the results of the surgical outcomes. The mean age of the patients was 50.3 +/- 14.4 years, and the mean follow-up period was 11.1 +/- 5.9 months. A diagnosis of chronic open angle glaucoma was made in 7 eyes and a diagnosis of secondary glaucoma in 5 eyes. The mean preoperative IOP was 25.8 +/- 11.9 mmHg, the immediate postoperative IOP was 6.4 +/- 2.9 mmHg, and at the final follow-up, the IOP was 11.9 +/- 2.5 mmHg. The IOP in 5 eyes was under 6 mmHg temporarily. However, there was no serious complication such as shallow anterior chamber. DSCI is considered to be a good surgical procedure that has similar surgical outcomes to a conventional trabeculectomy without serious complications.

A case of glaucoma associated with Sturge-Weber syndrome and Nevus of Ota

The Sturge-Weber syndrome consists of a unilateral port-wine hemangioma of the skin along the trigeminal distribution and is accompanied by an ipsilateral leptomeningeal angioma. Glaucoma is present in approximately half of the cases. The Nevus of Ota is a melanocytic pigmentary disorder, most commonly involving the area innervated by the trigeminal nerve. Elevated intraocular pressure, with or without glaucomatous damage, is observed in 10% of the cases. We report the first case of glaucoma associated with Sturge-Weber syndrome and Nevus of Ota in Korea.

Restrictive cardiomyopathy in a patient with extrahepatic biliary atresia

The most commonly associated anomalies in patients with extrahepatic biliary atresia are cardiovascular, digestive and splenic defects. Of the cardiovascular anomalies, there are very few reports of biliary atresia with cardiomyopathy. We report the first case of a child with extrahepatic biliary atresia and restrictive cardiomyopathy. The patient was a 13-month-old boy diagnosed with extrahepatic biliary atresia at the age of 2 months, when he underwent laparotomy for definite diagnosis.Hepatic portoenterostomy was performed after confirmative cholangiogram. Recently, he developed severe cough and dyspnea, and his respiratory symptoms worsened. Chest radiograph showed cardiomegaly. Two- dimensional echocardiography showed marked biatrial enlargement. On M- mode echocardiogram, a slight increase in left ventricular dimension was seen in early diastole with a relatively good left ventricular function. Mitral inflow Doppler tracing showed an increased E-velocity (1.1 m/sec) with decreased deceleration time (75 m/sec), and increased E/A ratio (0.33). He was diagnosed as having restrictive cardiomyopathy with characteristic echocardiographic features.

Comparisons of intraocular-pressure- lowering efficacy and side effects of 2% dorzolamide and 1% brinzolamide

Forty-one healthy volunteers were recruited for a study to compare the intraocular pressure (IOP)-lowering efficacy and side effects of 2% dorzolamide and 1% brinzolamide. In a randomized double-blind design, one eye received one drop of 2% dorzolamide and the other eye received one drop of 1% brinzolamide. The IOP and side effects were evaluated by Goldmann applanation tonometry and slit lamp biomicroscopy before administration, and 3, 7 and 14 days after the initial administration of eyedrops. The IOP decreased significantly from baseline for both drugs (p < 0.05). However, there were no statistically significant differences between 2% dorzolamide and 1% brinzolamide either before or after eyedrop administration (p > 0.05). The most frequent side effect was ocular pain in the case of 2% dorzolamide and blurred vision in 1% brinzolamide. The results suggested that 2% dorzolamide and 1% brinzolamide have similar IOP-lowering efficacies with different side effects

Influence of glutathione S-transferase M1 and T1 genotypes on larynx cancer risk among Korean smokers

Glutathione S-transferase (GST) isoenzymes are involved in the detoxification of major carcinogens present in tobacco smoke. It is thus conceivable that deficiency in GST activity due to homozygous deletions of the GSTM1 and GSTT1 genes (the null genotypes) may modulate susceptibility to smoking-induced cancers. The influence of the GSTM1 and GSTT1 null genotypes on larynx cancer risk among the Korean population were evaluated using peripheral blood DNA from 82 larynx cancer patients and 63 healthy controls, all of whom were male current smokers. Increased larynx cancer risk was related to the GSTM1 null genotype (odds ratio (OR)=3.53, 95% confidence interval (CI)=1.27-9.83). The OR associated with the GSTT1 null genotype was also increased, but did not reach statistical significance (OR=1.83, 95% CI=0.70-4.79). Individuals lacking both the GSTM1 and GSTT1 genes were at a significantly higher risk for larynx cancer than individuals with both genes present (OR=4.04, 95% CI=1.33-12.30). These data confirm that the GSTM1 null genotype is an important risk modifier for larynx cancer among Korean smokers and combined GSTM1 and GSTT1 null genotypes could be a useful predictor of genetic susceptibility to larynx cancer.

Clinical usefulness of serum and plasma vascular endothelial growth factor in cancer patients: which is the optimal specimen?

Vascular endothelial growth factor (VEGF) is secreted by various human cancer cells and plays a key role in cancer angiogenesis and metastasis. Recently, evidence of VEGF storage in blood cells including platelets has been reported. The serum VEGF levels were reported to increase during clotting as a result of its release from platelets, and plasma sample instead of serum was recommended for measuring the circulating VEGF more accurately. However, platelets have been implicated in tumor metastasis since circulating tumor cells forming aggregates with platelets were observed. The purpose of this study was to clarify which is an optimal specimen to measure VEGF in cancer patients, serum or plasma. We measured serum and plasma VEGF levels and platelet counts in 173 cancer patients and 42 healthy people, and found that serum VEGF levels were significantly higher than matched plasma VEGF and the VEGF difference (serum VEGF - plasma VEGF) correlated with platelet counts (r=0.624, p<0.05) in both cancer patients and healthy controls. We selected cancer patients with normal platelet counts (130-400x103/microl, Plt-normal cancer group). Interestingly, serum VEGF levels were higher in Plt-normal cancer group than in healthy controls. The theoretical platelet-derived VEGF in serum, calculated based on actual blood platelet counts (pg per 106 platelets), was also significantly higher in Plt-normal cancer group than in normal controls. It is, therefore, suggested that, although the serum VEGF levels are affected by blood platelets, platelet-derived VEGF also reflect biology of cancer cells, and that serum would be the more useful specimen for measurement of circulating VEGF in cancer patients for prognosis.

Effect of 0.2% brimonidine in preventing intraocular pressure elevation after Nd:YAG laser posterior capsulotomy

BACKGROUND AND OBJECTIVE

To determine the prophylactic effect of 0.2% brimonidine in reducing the elevated intraocular pressure (IOP) in patients undergoing Nd:YAG laser posterior capsulotomy.

PATIENTS AND METHODS

The 81 patients (81 eyes), who underwent Nd:YAG laser posterior capsulotomy, were allocated to two treatment groups. One drop of 0.2% brimonidine or vehicle was instilled 1 hour preoperatively and one drop immediately after capsulotomy. IOPs were measured preoperatively and 1, 2, 3, and 24 hours postoperatively.

RESULTS

Intraocular pressure decreased from the baseline in the brimonidine group by the third postoperative hour (P<0.05), while the vehicle group exhibited an increase. Intraocular pressure elevations of 5 mm Hg or greater occurred in 7.3% (3/41) in the brimonidine group compared to 20.0% (8/40) in the vehicle group. IOP elevations of 10 mm Hg or greater occurred in 2.4% (1/41) in the brimonidine group compared to 7.5% (3/40) in the vehicle group.

CONCLUSIONS

One drop of 0.2% brimonidine instilled 1 hour preoperatively and immediately after capsulotomy was found to be efficacious and safe in preventing IOP elevations that frequently follow Nd:YAG laser posterior capsulotomy.

Clinical usefulness of serum and plasma vascular endothelial growth factor in cancer patients: which is the optimal specimen?

Vascular endothelial growth factor (VEGF) is secreted by various human cancer cells and plays a key role in cancer angiogenesis and metastasis. Recently, evidence of VEGF storage in blood cells including platelets has been reported. The serum VEGF levels were reported to increase during clotting as a result of its release from platelets, and plasma sample instead of serum was recommended for measuring the circulating VEGF more accurately. However, platelets have been implicated in tumor metastasis since circulating tumor cells forming aggregates with platelets were observed. The purpose of this study was to clarify which is an optimal specimen to measure VEGF in cancer patients, serum or plasma. We measured serum and plasma VEGF levels and platelet counts in 173 cancer patients and 42 healthy people, and found that serum VEGF levels were significantly higher than matched plasma VEGF and the VEGF difference (serum VEGF - plasma VEGF) correlated with platelet counts (r=0.624, p<0.05) in both cancer patients and healthy controls. We selected cancer patients with normal platelet counts (130-400x103/microl, Plt-normal cancer group). Interestingly, serum VEGF levels were higher in Plt-normal cancer group than in healthy controls. The theoretical platelet-derived VEGF in serum, calculated based on actual blood platelet counts (pg per 106 platelets), was also significantly higher in Plt-normal cancer group than in normal controls. It is, therefore, suggested that, although the serum VEGF levels are affected by blood platelets, platelet-derived VEGF also reflect biology of cancer cells, and that serum would be the more useful specimen for measurement of circulating VEGF in cancer patients for prognosis.

Effect of IOP elevation on matrix metalloproteinase-2 in rabbit anterior chamber

To investigate changes in the level of matrix metalloproteinase-2 (MMP-2) in the anterior chamber of rabbit with intraocular pressure (IOP) elevation. The IOP was elevated with scleral encircling in 12 rabbits. In the control group (4 rabbits), IOP was not changed after scleral encircling, and in group 1 (4 rabbits) and 2 (4 rabbits), IOP was elevated about 10 and 20 mmHg respectively after scleral encircling. At 2 days after scleral encircling, aqueous sampling was performed and levels of MMP-2 were checked by Western blots and gelatin zymograms. The greater the IOP elevation, the more MMP-2 expression in the anterior chamber by Western blots and gelatin zymograms. The increase in MMP-2 expression in response to IOP elevation may have important implications for the IOP feedback control mechanism.

The effective concentration and exposure time of mitomycin-C for the inhibition of lens epithelial cell proliferation in rabbit eyes

The proliferation of residual lens epithelial cells following cataract surgery is assumed to be a major cause of posterior capsular opacification. To assess the efficacy of mitomycin-C in preventing posterior capsular opacification, we determined the effective concentration and exposure time of mitomycin-C in inhibiting rabbit lens epithelial cell proliferation. The fourth-passaged rabbit lens epithelial cells were maintained for one day and then exposed to mitomycin-C for 1, 2, 3, and 5 minutes, respectively. There were 9 different plating concentrations of mitomycin-C with two-fold serial dilution. The maintenance of the phenotypic properties of lens epithelial cells was confirmed by continuous transcription of lambda-crystalline mRNA determined by reverse transcription-polymerase chain reaction and the polymorphism of the restriction fragment. Cell proliferation was assayed with 3H-thymidine incorporation into DNA. The fourth-passaged cells maintained the expression of lambda-crystalline mRNA, suggesting that they are phenotypically authentic lens epithelial cells. The effective concentrations and exposure time of mitomycin-C were 0.1 mg/ml for 1 minute and 2 minutes, and 0.025 mg/ml for 2 minutes. By these results, we postulated that mitomycin-C at relatively short incubation times could be clinically used for prevention of posterior capsular opacification after cataract surgery.

Enantiomeric synthesis of (S)-2-methylbutanoic acid methyl ester, apple flavor, using lipases in organic solvent

Enantiomeric selective synthesis of (S)-2-methylbutanoic acid methyl ester, which is known as a major apple and strawberry flavor, was performed from racemic 2-methylbutanoic acid using lipases in organic solvent. Among 20 lipases, lipase IM 20 (immobilized lipase of Rhizomucor miehei), lipase AP (Aspergillus niger), and lipase FAP-15 (Aspergillus javanicus) exhibited higher enzymatic activities and enantioselectivities and were selected for the synthesis of (S)-2-methylbutanoic acid methyl ester. Using these enzymes, the reaction conditions such as temperature and lyophilizing pH were optimized, and kinetic parameters were determined. All of the reactions were performed in isooctane, which was identified as the best reaction media for nonaqueous systems. At 20 degrees C maximum enantiomeric excess was observed, while synthetic activity increased as the temperature increased. Only lipases lyophilized at pH 5.5, 6. 0, 6.5, and 7.0 showed synthetic activity. In this pH range, enantioselectivities were not influenced by the lyophilizing pH. The K(M,S) and K(M,R) values for ester synthetic activity of lipase were 1120 and 1240 mM, respectively. Enzyme activity was inhibited by (S)-2-methylbutanoic amide, and its K(i) was calculated as 84 mM. (S)-2-Methylbutanoic amide acted as a competitive inhibitor.

Needle thoracic sympathectomy for essential hyperhidrosis: intermediate-term follow-up

BACKGROUND

Essential hyperhidrosis is a condition with excessive sweating localized to certain part of the body. A definitive cure can be obtained by upper thoracic sympathectomy.

METHOD

Between June and October 1997, 117 patients with essential hyperhidrosis underwent needle thoracoscopic sympathectomy. Of the 94 patients, 42 were men and 52 women. Their ages ranged from 14 to 63 years, with a mean age of 23 years.

RESULTS

There were no mortality or life-threatening complications. Symptomatic improvement was found in 95.7%. Compensatory hyperhidrosis was found in 71.2% of the patients, but in these compensatory hyperhidrosis were mostly tolerable.

CONCLUSIONS

This therapeutic procedure is minimally invasive and very effective. Further development of the new device and surgical technique are expected to follow.

Thoracoscopic sympathetic surgery for hyperhidrosis

Resectional surgery of sympathetic nerves has been known to be the most effective treatment for essential hyperhidrosis and the application of thoracoscopic electrocauterization has provided a minimally-invasive procedure with the least morbidity and a resultant higher satisfaction rate. This paper describes our experience on the 1,167 cases of thoracoscopic sympathetic surgery for the treatment of essential hyperhidrosis. A total of 1,167 patients (674 males (58%) and 493 females (42%), mean age of 26.4 years with palmar (930), craniofacial (190) or axillary (47) hyperhidrosis underwent thoracoscopic sympathetic surgery from July 1992 to March 1999. Since the T2-4 sympathectomy, first performed in July 1992 for a patient of palmar hyperhidrosis, the operative methods have been altered to achieve a higher satisfaction level with the least complication by adopting less invasive procedures. Our current standard procedures being performed are T3 and T2 clipping for palmar and craniofacial hyperhidrosis and T3,4 sympathicotomy for axillary hyperhidrosis, all using a 2 mm needle thoracoscope. As the surgical procedures have been transited to a less invasive method with limited resection using the newest endoscopic devices, the average operation time and complications such as Horner's syndrome and compensatory hyperhidrosis have gradually decreased and thus the long-term satisfaction rate has been raised up to 98% for palmar hyperhidrosis, 92% for craniofacial hyperhidrosis and 89% for axillary hyperhidrosis. The recurrent cases (14/1167) were treated successfully with reoperations of thoracoscopic sympathetic surgery. The optimal goal of therapy could be achieved by complete elimination of the hyperhidrotic symptom, by decreasing the incidence and degree of compensatory hyperhidrosis through a selective and limited resection, and by adopting the least invasive procedures. Sympathicotomy has provided the advantages of a limited extent of denervation and the resultant decrease of compensatory hyperhidrosis compared to sympathectomy. The reversible method of clipping may be an effective, provisionary means for cases of severe, intractable compensatory sweating. For craniofacial hyperhidrosis, T2 sympathicotomy or clipping has been proven to be superior to the T1 sympathectomy due to the decreased occurrence of Horner's syndrome and T3,4 sympathicotomy providing a satisfactory outcome with less compensatory hyperhidrosis for axillary hyperhidrosis.

Effects of 0.005% latanoprost on optic nerve head and peripapillary retinal blood flow

Fifty-two eyes of 26 healthy volunteers were recruited for evaluating the effects of 0.005% latanoprost on optic nerve head (ONH) and peripapillary retinal blood flow. In a randomized double-blind design, one eye received one drop of 0.005% latanoprost and its fellow eye received one drop of a placebo eyedrop. Intraocular pressure (IOP), ONH and peripapillary retinal blood flow were measured with Heidelberg retinal flowmetry (HRF) before, 2 and 24 h after administration of eyedrops. IOP was decreased significantly in latanoprost-treated eyes at 2 and 24 h after administration (p < 0.05). In the volume, flow or velocity of ONH and peripapillary retina, there were no significant changes from the baseline values at 2 and 24 h after latanoprost administration in either latanoprost-treated eyes or their fellow eyes (p > 0.05). No significant differences were found in the measured quantities between latanoprost-treated eyes and their fellow eyes at each time point (p > 0.05). This result may suggest that 0.005% latanoprost in healthy subjects does not have any adverse effect on ONH and peripapillary retinal blood flow.

A case of parenchymal pulmonary endometriosis

Pulmonary Endometriosis is a rare disease entity and we report a 23-year-old single woman with a history of hemoptysis in association with menstruation. She was previously treated effectively with hormone therapy for 3 months, but decided to undergo surgical resection because of the high cost of hormone therapy. Radiographic finding of the chest showed haziness in the right lower lung field, and chest CT showed a ground-glass appearance in the posterobasal and laterobasal segment. The patient underwent basal segmentectomy of the right lower lobe. There was no incidence of hemoptysis during her menstruation following the operation.

The changes in main pulmonary artery pressure after bilateral lung autotransplantation in dogs

In the Respiratory Center, Yongdong Severance Hospital, Yonsei University, we performed 10 cases of bilateral lung autotransplantation in mongrel dogs from July 1994 to June 1996, and we have analyzed the hemodynamic changes. Autotransplantation was performed in order to avoid postoperative rejection. The lung was flushed with an Euro-Collins(E-C) solution containing PGE1 which passed through a 10 French catheter inserted into an incision on the anterior half of the pulmonary artery to pulmonary parenchyme, and the vertical incision was made on the anterior half of the left atrium near the proximal part of the pulmonary vein. However, the bronchus was totally divided after clamping both sides. The lung was kept cold (4 degrees C) in the thoracic cavity for an hour by using slushed ice made from an E-C solution. After an hour of cold ischemia, the pulmonary artery was sutured with Prolene 5-0. The pulmonary vein was sutured with Prolene 6-0 by using the continuous everting mattress method. The main bronchus was anastomosed using the telescope method. The arterial oxygen concentration and the pressures in the femoral and pulmonary arteries were measured both preoperatively and postoperatively. There were no significant hemodynamic differences between the preoperative and postoperative mean pulmonary artery pressure (MPAP) (paired t-test, P = 0.05). Lung preservation using a cold (4 degrees C) E-C solution containing PGE1 may be an acceptable method for short-term storage of a lung (for about an hour) in bilateral lung autotransplantation in dogs.

The effect of mitomycin-C on postoperative corneal astigmatism in trabeculectomy and a triple procedure

BACKGROUND AND OBJECTIVE

The authors attempted to determine the effect of mitomycin-C (MMC) on postoperative corneal astigmatism in patients who underwent trabeculectomy or a triple procedure (trabeculectomy, extracapsular cataract extraction, and intraocular lens implantation).

PATIENTS AND METHODS

Using the vector analysis method, the authors measured the postoperative induced astigmatism of 76 eyes in 59 patients who underwent trabeculectomy or a triple procedure with or without the application of MMC. Postoperative induced astigmatism corresponding to the 180 degrees axis was compared between the two groups.

RESULTS

The patients who underwent trabeculectomy with or without MMC showed a mean induced astigmatism of -1.01 D and -2.63 D, respectively, after 1 month (P < .05), and 0.34 D and -1.42 D after 12 months (P < .05). Those who underwent a triple procedure with or without MMC showed a mean induced astigmatism of -1.81 D and -4.50 D, respectively, after 7 days (P < .05), and 1.73 D and -0.13 D, respectively, after 12 months (P < .05). The entire amount of postoperative against-the-rule astigmatic shift was similar between the with-MMC group and the without-MMC group. The against-the-rule astigmatic shift of the group without MMC reached a plateau after 3 months. However, the group with MMC showed continuous against-the-rule astigmatic shift until 12 months.

CONCLUSION

This study suggests that MMC induces less with-the-rule astigmatism in early postoperative periods and continuous against-the-rule shift after 3 months following a trabeculectomy or a triple procedure.

The causative organisms of bacterial meningitis in Korean children, 1986-1995

Bacterial meningitis remains a serious cause of morbidity and mortality in childhood. Epidemiologic investigations have shown variability in disease risks among different populations and races. In Korea, however, basic epidemiologic information on bacterial meningitis in children is limited. The main purpose of this study was to analyze bacteriologically proven meningitis cases in terms of the relative frequency of causative organisms, mortality rate, and age distribution beyond the neonatal period. Data was obtained from the hospital records who had been diagnosed with bacterial meningitis at 13 general or university hospitals from 1986 through 1995. The patients had at least one positive CSF culture for bacteria. Of 140 cases of CSF culture-proven bacterial meningitis, 46.4% was < or =1 year, 62.1% was < or =2 years, 81.4% was < or =5 years cumulatively. Streptococcus pneumoniae was the most common bacteria responsible for 48 (35.0%) of all cases regardless of age, followed by Haemophilus influenzae for 48 (34.3%) and Neisseria meningitidis for 8 (6.4%) patients. The case fatality rate was 20.0%, 17.1%, and 16.7% for N. meningitidis, S. pneumoniae, and H. influenzae, respectively. In conclusion, the most common organisms of culture-proven bacterial meningitis in the last 10 years have been S. pneumoniae, H. influenzae, and N. meningitidis in order of frequency. Further study should be extended to nation-wide epidemiologic evaluation to show the incidence of bacterial meningitis caused by these three important organisms.

Laser trabeculoplasty: how little is enough?

BACKGROUND AND OBJECTIVE

The optimal number of laser applications for argon laser trabeculoplasty in patients with primary open-angle glaucoma has not been established. The purpose of this study was to determine the fewest number of burns necessary for clinically effective intraocular pressure reduction for these patients.

PATIENTS AND METHODS

Using a prospective, randomized, collaborative study, the authors examined the relationship between the number of laser trabeculoplasty burns and intraocular pressure for patients with primary open-angle glaucoma. A total of 122 patients received either 50 burns to half of the trabecular meshwork (group 1) or 35 burns to one third of the trabecular meshwork (group 2).

RESULTS

The mean baseline intraocular pressures were similar between group 1 (22.3 +/- 4.1 mm Hg [mean +/- SD]) and group 2 (22.8 +/- 5.0 mm Hg) (P = .58). Intraocular pressure reduction at 9 to 12 months, although significant in both groups (group 1: 4.4 +/- 3.0 mm Hg, P < .0001; group 2: 3.9 +/- 5.1 mm Hg, P < .0001), did not differ significantly between the two groups (P = .63).

CONCLUSION

This study demonstrated that 35 burns may be as clinically effective as 50 burns in reducing the intraocular pressure in primary open-angle glaucoma patients.

Relationship between optic disc cupping change and intraocular pressure control in adult glaucoma patients

BACKGROUND

Until recently, there has been a paucity of quantitative evidence for intraocular pressure (IOP)-dependent optic disc cupping change in adult glaucoma patients. Therefore, we investigated the relationship between optic disc cupping change and IOP control.

METHODS

The study involved 78 eyes of 78 randomly selected adult patients with early to moderate chronic open-angle glaucoma (CO-AG), treated on various therapeutic regimens, who had had two consecutive successful optic disc analyses with the Rodenstock Optic Nerve Head Analyzer 15.8 +/- 14.8 weeks apart.

RESULTS

The mean initial IOP of 27 eyes (34%) with cupping reversal did not differ from that of 17 eyes (22%) demonstrating progressive deterioration (29.2 +/- 8.8 vs 26.2 +/- 6.1 mmHg, P > 0.5), but the reversal group did have a significantly greater mean IOP decrease than the progression group (-10.8 +/- 7.9 vs-1.0 +/- 7.7 mmHg, P < 0.001) and significantly lower mean final IOP (18.3 +/- 6.1 vs 25.2 +/- 7.9 mmHg, P < 0.003).

CONCLUSION

A decrease of optic disc cupping is more likely with a greater IOP reduction and a lower final IOP, and an increase of cupping is more likely with less or no IOP reduction and a higher final IOP.

Intraocular pressure after a two-week washout following long-term timolol or levobunolol

The effect on intraocular pressure (IOP) of a 2-week washout following long-term ocular therapy with topical levobunolol or timolol for an average period of 30 months was investigated in 20 patients (11 whites and 9 blacks) with early primary open-angle glaucoma or ocular hypertensive glaucoma suspect status. The 2-week washout IOP was significantly lower than the pretreatment baseline IOP in the total 20 patients (P < 0.001), and in the 9 black patients (P = 0.004), but not in the 11 white patients (P = 0.065). However, the washout IOP was found to be significantly lower than the baseline IOP in the 5 whites with brown irides (P = 0.024) but not in the 6 whites with blue irides (P = 0.574). Thus, the 2-week washout following long-term ocular therapy with a topical beta 1-, beta 2-blocker appears insufficient to restore IOP to the pretreatment baseline level in blacks and in the whites with brown irides, whereas it may be adequate in the majority of the whites with blue irides.