Panretinal Photocoagulation vs Intravitreous Ranibizumab for Proliferative Diabetic Retinopathy: A Randomized Clinical Trial

IMPORTANCE

Panretinal photocoagulation (PRP) is the standard treatment for reducing severe visual loss from proliferative diabetic retinopathy. However, PRP can damage the retina, resulting in peripheral vision loss or worsening diabetic macular edema (DME).

OBJECTIVE

To evaluate the noninferiority of intravitreous ranibizumab compared with PRP for visual acuity outcomes in patients with proliferative diabetic retinopathy.

DESIGN, SETTING, AND PARTICIPANTS

Randomized clinical trial conducted at 55 US sites among 305 adults with proliferative diabetic retinopathy enrolled between February and December 2012 (mean age, 52 years; 44% female; 52% white). Both eyes were enrolled for 89 participants (1 eye to each study group), with a total of 394 study eyes. The final 2-year visit was completed in January 2015.

INTERVENTIONS

Individual eyes were randomly assigned to receive PRP treatment, completed in 1 to 3 visits (n = 203 eyes), or ranibizumab, 0.5 mg, by intravitreous injection at baseline and as frequently as every 4 weeks based on a structured re-treatment protocol (n = 191 eyes). Eyes in both treatment groups could receive ranibizumab for DME.

MAIN OUTCOMES AND MEASURES

The primary outcome was mean visual acuity change at 2 years (5-letter noninferiority margin; intention-to-treat analysis). Secondary outcomes included visual acuity area under the curve, peripheral visual field loss, vitrectomy, DME development, and retinal neovascularization.

RESULTS

Mean visual acuity letter improvement at 2 years was +2.8 in the ranibizumab group vs +0.2 in the PRP group (difference, +2.2; 95% CI, -0.5 to +5.0; P < .001 for noninferiority). The mean treatment group difference in visual acuity area under the curve over 2 years was +4.2 (95% CI, +3.0 to +5.4; P < .001). Mean peripheral visual field sensitivity loss was worse (-23 dB vs -422 dB; difference, 372 dB; 95% CI, 213-531 dB; P < .001), vitrectomy was more frequent (15% vs 4%; difference, 9%; 95% CI, 4%-15%; P < .001), and DME development was more frequent (28% vs 9%; difference, 19%; 95% CI, 10%-28%; P < .001) in the PRP group vs the ranibizumab group, respectively. Eyes without active or regressed neovascularization at 2 years were not significantly different (35% in the ranibizumab group vs 30% in the PRP group; difference, 3%; 95% CI, -7% to 12%; P = .58). One eye in the ranibizumab group developed endophthalmitis. No significant differences between groups in rates of major cardiovascular events were identified.

CONCLUSIONS AND RELEVANCE

Among eyes with proliferative diabetic retinopathy, treatment with ranibizumab resulted in visual acuity that was noninferior to (not worse than) PRP treatment at 2 years. Although longer-term follow-up is needed, ranibizumab may be a reasonable treatment alternative, at least through 2 years, for patients with proliferative diabetic retinopathy.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT01489189.

Guidelines for the management of neovascular age-related macular degeneration by the European Society of Retina Specialists (EURETINA)

Age-related macular degeneration (AMD) is still referred to as the leading cause of severe and irreversible visual loss world-wide. The disease has a profound effect on quality of life of affected individuals and represents a major socioeconomic challenge for societies due to the exponential increase in life expectancy and environmental risks. Advances in medical research have identified vascular endothelial growth factor (VEGF) as an important pathophysiological player in neovascular AMD and intraocular inhibition of VEGF as one of the most efficient therapies in medicine. The wide introduction of anti-VEGF therapy has led to an overwhelming improvement in the prognosis of patients affected by neovascular AMD, allowing recovery and maintenance of visual function in the vast majority of patients. However, the therapeutic benefit is accompanied by significant economic investments, unresolved medicolegal debates about the use of off-label substances and overwhelming problems in large population management. The burden of disease has turned into a burden of care with a dissociation of scientific advances and real-world clinical performance. Simultaneously, ground-breaking innovations in diagnostic technologies, such as optical coherence tomography, allows unprecedented high-resolution visualisation of disease morphology and provides a promising horizon for early disease detection and efficient therapeutic follow-up. However, definite conclusions from morphologic parameters are still lacking, and valid biomarkers have yet to be identified to provide a practical base for disease management. The European Society of Retina Specialists offers expert guidance for diagnostic and therapeutic management of neovascular AMD supporting healthcare givers and doctors in providing the best state-of-the-art care to their patients.

TRIAL REGISTRATION NUMBER

NCT01318941.

Treatment techniques and clinical guidelines for photocoagulation of diabetic macular edema. Early Treatment Diabetic Retinopathy Study Report Number 2. Early Treatment Diabetic Retinopathy Study Research Group

The Early Treatment Diabetic Retinopathy Study (ETDRS) has recently shown that argon laser photocoagulation treatment is beneficial in reducing the risk of visual loss from clinically significant diabetic macular edema. The ETDRS treatment consisted of a combination of focal treatment to individual-leaking microaneurysms and grid treatment to areas of diffuse leakage and capillary nonperfusion. These techniques are described in detail, and the concepts of "clinically significant macular edema" and "treatable lesions" are defined. Guidelines for the application of ETDRS findings to clinical practice are discussed.

Argon laser scatter photocoagulation for prevention of neovascularization and vitreous hemorrhage in branch vein occlusion. A randomized clinical trial. Branch Vein Occlusion Study Group

The Branch Vein Occlusion Study is a multicenter, randomized, controlled clinical trial designed to answer several questions regarding the management of complications of branch vein occlusion. This report addresses the questions, "Can peripheral scatter argon laser photocoagulation prevent the development of neovascularization?" and "Can peripheral scatter argon laser photocoagulation prevent vitreous hemorrhage?" To answer the first question, 319 eyes were assigned randomly to either a treated or an untreated control group. Comparing treated patients with control patients (average follow-up time, 3.7 years), the development of neovascularization was significantly less in treated eyes (P = .009, log rank test). To answer the second question, 82 eyes were assigned randomly to either a treated or untreated control group. Comparing treated patients with control patients (average follow-up time, 2.8 years), the development of vitreous hemorrhage was significantly less in treated eyes (P = .005, log rank test). Although the Branch Vein Occlusion Study was not designed to determine whether peripheral scatter treatment should be applied before rather than after the development of neovascularization, data accumulated in this study suggest that peripheral scatter treatment should be applied after the development of neovascularization rather than before the development of neovascularization. Because the occurrence of vitreous hemorrhage was lessened by peripheral scatter argon laser photocoagulation, we recommend laser photocoagulation for patients with branch vein occlusion who have developed neovascularization and who meet the eligibility criteria of this study.

Use of the holmium:YAG laser in urology

The tissue effects of a holmium:YAG (Ho:YAG) laser operating at a wavelength of 2.1 mu with a maximum power of 15 watts (W) and 10 different energy-pulse settings was systematically evaluated on kidney, bladder, prostate, ureteral, and vasal tissue in the dog. In addition, various urologic surgical procedures (partial nephrectomy, transurethral laser incision of the prostate, and laser-assisted vasovasostomy) were performed in the dog, and a laparoscopic pelvic lymph node dissection was carried out in a pig. Although the Ho:YAG laser has a strong affinity for water, precise tissue ablation was achieved in both the contact and non-contact mode when used endoscopically in a fluid medium to ablate prostatic and vesical tissue. Using the usual parameters for tissue destruction (blanching without charring), the depth of thermal injury in the bladder and ureter was kept superficial. In performing partial nephrectomies, a 2-fold reduction in the zone of coagulative necrosis was demonstrated compared to the use of the continuous wave Neodymium:YAG laser (Nd:YAG). When used through the laparoscope, the Ho:YAG laser provided precise cutting and, combined with electrocautery, allowed the dissection to proceed quickly and smoothly. Hemostatic control was adequate in all surgical procedures. Although the results of these investigations are preliminary, our initial experience with the Ho:YAG laser has been favorable and warrants further investigations.

Comparison of the maximum coagulation depth in human skin for different types of medical lasers

The values for the maximum coagulation depth (MCD) of various types of lasers which are specified in the literature are not comparable, because often different irradiation times were used. MCD depends not only on the wavelength of laser light, but also on the time of action of the laser beam, because of heat transfer. In excised human skin MCD was determined histologically for irradiation with the argon laser, Nd:YAG laser, and CO2 laser. Extending the irradiation time from 0.2 s to 10 s results in a 4-6-fold increase in MCD. Coagulation experiments performed with a soldering iron have shown results similar to those obtained with the CO2 laser. Enlargement of the laser-beam diameter from 1 to 2 mm leads to a 50% increase in MCD. Additional chilling of the skin with water during laser irradiation protects the skin from evaporation, and the values for MCD increase to 3.5 mm for the argon laser and 5.5 mm for Nd:YAG laser. Detailed knowledge of the MCD is necessary to obtain the desired therapeutic effect, and also to avoid unwanted effects.

Use of the pulsed Nd:YAG laser for intraoral soft tissue surgery

Application of a neodymium:yttrium-aluminum-garnet (Nd:YAG) laser was compared to conventional scalpel in dental soft tissue surgery. Two surgery sites on 29 patients were randomly selected and treated. An additional 41 patients were exclusively treated with the Nd:YAG laser. The surgical technique was then evaluated for periodontal pocket depths, degree of pain perceived, bleeding, inflammation, procedure time, and anesthesia. Surgical prognosis was made at the time of surgery and compared to actual healing 1 week and 1 month after surgery. No differences were observed between laser and scalpel surgery in terms of pocket depth reduction, postoperative pain, post-operative inflammation, and treatment time. However, operative and postoperative bleeding with laser surgery were significantly less than with conventional surgery. Anesthesia is required for scalpel surgery, the majority of laser-treated sites evoked minimal pain without anesthesia. These results indicate that the Nd:YAG laser can be used successfully for intraoral soft tissue applications are well tolerated without anesthesia and minimal bleeding compared to scalpel surgery.

Retinal arterial macroaneurysms

Retinal arterial macroaneurysms represent a distinct clinical entity. Macroaneurysms are seen in the elderly with a marked female predominance and a strong association with hypertension and arteriosclerotic vascular changes. The classic appearance provides an easy diagnosis; however, variable presentations, such as subretinal hemorrhage, macular exudate, and epiretinal membranes can make the diagnosis difficult. The differential diagnosis of retinal arterial macroaneurysms include retinal telangiectasia, angiomatosis retinae, venous macroaneurysms, background diabetic retinopathy, and cavernous hemangioma. The clinical characteristics of the reported cases are summarized, and our series of 60 patients is presented. The natural history of most macroaneurysms is spontaneous involution without loss of vision. However, visual loss may occur secondary to macular edema, exudate, hemorrhage and neurosensory retinal detachment, and photocoagulation may expedite visual recovery. Photocoagulation treatment may be applied directly to the macroaneurysm, indirectly by surrounding the macroaneurysm, or as a combination of these two methods.

Percutaneous sonographically guided microwave coagulation therapy for hepatocellular carcinoma: results in 234 patients

OBJECTIVE

The objective of our study was to evaluate the long-term results of percutaneous microwave coagulation therapy for the treatment of hepatocellular carcinoma in a large patient population.

SUBJECTS AND METHODS

Survival rates were determined in 234 patients with 339 nodules of hepatocellular carcinoma who had undergone percutaneous microwave coagulation therapy (208 men, 26 women; mean age, 54.8 years; mean tumor size, 4.1 +/- 1.9 cm; range, 1.2-8.0 cm; mean follow-up period, 27.9 months). Patients were those who had been rejected as candidates for surgery by the surgery department, who fit our study's criteria, and who agreed to participate. After baseline imaging studies were performed, the patients were followed up using the same combination of imaging (sonography, CT, or MR imaging) and posttreatment biopsy.

RESULTS

After percutaneous microwave coagulation therapy, color Doppler flow signals disappeared in 92.0% (263/286) of the lesions. No enhancement was apparent in 89.2% (190/213) and 89.1% (41/46) of the lesions on contrast-enhanced CT and MR imaging, respectively. Posttreatment biopsies of 194 nodules showed no evidence of surviving tumor tissue in 180 nodules (92.8%). Resections of six lesions revealed complete tumor necrosis in five. The 1-, 2-, 3-, 4-, and 5-year cumulative survival rates were 92.70%, 81.60%, 72.85%, 66.37%, and 56.70%, respectively. The relationships between survival curves and the degree of hepatocellular carcinoma tumor differentiation and between survival curves and tumor size were statistically significant (p = 0.021). No severe complications were seen.

CONCLUSION

Sonographically guided microwave coagulation proved to be safe and effective for the treatment of hepatocellular carcinoma. This therapy resulted in a high percentage of cases without evidence of residual tumor and satisfactory long-term results.

Endovenous laser photocoagulation (EVLP) for varicose veins

BACKGROUND AND OBJECTIVES

Untreated varicose veins have significant morbidity and potential mortality. Treatment aims to relieve symptoms, improve appearance, and to prevent deterioration. Current therapeutic options include graduated compression stockings, sclerotherapy, ambulatory phlebectomy, surgical ligation, and stripping. Results of laser photocoagulation of vascular anomalies have been encouraging. Applying these concepts of laser-tissue interactions, we developed a new method of treatment for varicose veins of the lower extremities.

STUDY DESIGN/MATERIALS AND METHODS

One hundred and forty-nine patients with 252 varicose greater saphenous veins underwent endovenous laser photocoagulation (EVLP) from January 1996 to January 2000. Subject's age ranged between 23 years 9 months and 80 years 7 months with a mean age of 50 years 8 months. There were 122 females and 27 males. Only patients with primary varicose veins and saphenofemoral reflux documented by Duplex ultrasound were treated. All patients received surgical ligation of the saphenofemoral junction (SFJ). EVLP was performed using the neodymium:yttrium-aluminium-garnet (Nd:YAG) (1,064 nm) laser, delivered with a 600 microm optical fiber. Laser power was set at 10 or 15 W, delivered with a pulse duration of 10 seconds. The outcome was compared before and after EVLP, based on the score of severity of the varicose veins by Hach's classification.

RESULTS

The range of total delivered energy is from 9,200 to 20,100 J. The entire procedure was completed in 95-175 minutes (mean 122.33 minutes) for bilateral procedures, and 65-100 minutes (mean 81.07 minutes) for unilateral procedures. The follow-up period ranged from 12 to 28 months with a mean of 19 months. One hundred and forty-one patients with 244 legs involved (96.8%) demonstrated remarkable improvement (P < 0.05). Common early complications of EVLP are: local paraesthesia of the treated area in 92 legs (36.5%), ecchymosis and dyschromia in 58 legs (23.0%), superficial burn injury in 12 legs (4.8%), superficial phlebitis in four legs (1.6%), and localized hematoma in two legs (0.8%) at 3 weeks post-operatively. The final outcome showed no significant morbidity or mortality. All patients recovered completely.

CONCLUSIONS

EVLP is a simple effective treatment modality for varicose veins. This less invasive method can minimize the complications of conventional surgery.

Microphotocoagulation: selective effects of repetitive short laser pulses

Repetitive exposure to short laser pulses is shown to cause selective damage to absorbing structures (cells, organelles, or enzymes) with pulse energies below the threshold energy for single-pulse damage. Directly adjacent structures are spared in vivo. Additivity of (presumably nonphotochemical) subthreshold effects is demonstrated. Selective damage to the retinal pigment epithelium with sparing of the neural retina is shown (514 nm, 5 microseconds, 1-500 pulses at 500 Hz, 2- to 10-microJ pulse energy). A melanin granule model has been developed and applied to the experimental situation. Histological results as well as the basic mechanism for these effects are discussed.

Controlled trial of Nd-YAG laser photocoagulation in bleeding peptic ulcers

The efficacy of Nd-YAG laser photocoagulation in the endoscopic control of haemorrhage from peptic ulcers was shown in a controlled trial. 527 patients admitted consecutively with acute upper gastrointestinal haemorrhage underwent urgent endoscopy. Peptic ulcers were seen in 260. All 138 ulcer patients with stigmata of recent haemorrhage (SRH) accessible to laser therapy were included in the trial (26 inaccessible, 96 no SRH). Patients were stratified into three groups--those with a visible vessel, those with other SRH, and those with clot that could not be washed off before therapy. Laser and control groups were well matched for other factors known to influence prognosis. Overall, 7/70 laser-treated and 27/68 control ulcers rebled (p less than 0.001). Rebleeding occurred from 6/39 treated and 23/43 control ulcers with a visible vessel (p less than 0.001); 0/17 treated and 1/13 ulcers with other SRH (NS); and 1/13 treated and 2/11 control ulcers with overlying clots (NS). 7/70 treated but 24/68 controls required emergency surgery (p less than 0.005). 1 treated patient but 8 control patients died after an episode of rebleeding (p less than 0.05).

Infrared coagulator: a useful tool for treating anal squamous intraepithelial lesions

PURPOSE

The incidence of invasive anal squamous carcinoma in men who have sex with men is rising, particularly in those with human immunodeficiency virus. As in the cervix the high-grade squamous intraepithelial lesion is thought to be an invasive squamous cell carcinoma precursor. Cervical high-grade squamous intraepithelial lesions are treated by removing the squamocolumnar transition zone. This is not possible in the anus, where treatment is often surgical and is accompanied by significant pain and morbidity. Better office-based techniques to treat anal high-grade squamous intraepithelial lesions are needed. We employed the infrared coagulator in an office setting to ablate high-grade squamous intraepithelial lesions.

METHODS

A retrospective review of medical records was performed on 68 human immunodeficiency virus-positive men who have sex with men who underwent infrared coagulator ablation of biopsy-proven high-grade dysplasia from the time we began using the procedure in 1999. All patients have had at least six months of follow-up. Procedures were performed with local anesthesia on patients with discrete high-grade squamous intraepithelial lesions. Follow-up consisted of anal cytology with high-resolution anoscopy and biopsy of suspicious areas every three to six months. New or recurrent high-grade dysplasia was retreated. Patients with circumferential or bulky disease were treated in the operating room and were excluded from the study.

RESULTS

Altogether, 68 patients met the enrollment criteria. The median patient age was 41 years (range 29-62 years). A total of 165 lesions were treated (mean 1.6 lesions, range 1-5) and only 46 (28 percent) persisted. However, 44 patients (65 percent) developed a new or persistent high-grade squamous intraepithelial lesion within a median time of 217 days (range 27-566 days) after infrared coagulation. The remaining 24 patients (35 percent) were free of high-grade dysplasia for a median of 413 days (range 162-1313 days) after infrared coagulation. When patients were treated a second or third time, the incidence of new or persistent high-grade dysplasia dropped to 58 percent and 40 percent, respectively. The probability of curing a retreated lesion was 72 percent. Using generalized estimating equations, the incidence of high-grade dysplasia decreased with repeated infrared coagulator treatments. No patient developed squamous-cell carcinoma, had a serious adverse event, or developed anal stenosis.

CONCLUSIONS

The infrared coagulator is a safe, office-based modality for treating anal high-grade squamous intraepithelial lesion in human immunodeficiency virus-positive men who have sex with men. Successive treatments led to decreased recurrence rates.

Evaluation of a protocol for transscleral neodymium: YAG cyclophotocoagulation in one hundred patients

One hundred consecutive patients with intractable glaucoma underwent transscleral neodymium: YAG (Nd:YAG) cyclophotocoagulation using a standard protocol derived from a study of human autopsy eyes, and were followed prospectively for a minimum of 6 months. After the first treatment, 51 patients had a final intraocular pressure (IOP) between 7 and 20 mmHg (classified as "IOP success") and 17 more had an IOP less than 7 mmHg or more than 20 mmHg, but required no additional surgery ("qualified IOP success"). With one or more additional treatments, the totals rose to 65 IOP successes and 30 qualified IOP successes. Parameters associated with qualified success and failure were younger age and higher preoperative IOP. Forty-five patients in the cumulative IOP success and qualified IOP success groups had reduced visual acuity, although this could be attributed to other ocular problems in at least one half of the cases. Other postoperative complications included transient IOP rise in 23 patients, severe pain in 12 patients, and severe inflammation in 29 patients.

Histopathological findings in human choroidal melanomas after transpupillary thermotherapy

AIMS

The effect of transpupillary thermotherapy (TTT) on human choroidal melanomas was investigated by means of histopathology.

METHODS

Before enucleation TTT was performed in 11 eyes with a xenon are photocoagulator with a red filter or a diode laser at 810 nm. The exposure time was 1 minute; the estimated temperature at the top of the tumour was about 65 degrees C.

RESULTS

Seven of 11 tumours developed necrosis to a maximum depth of 3.9 mm with a sharp demarcation between the necrotic and the viable part of the tumour. The depth correlated with penetration of heat into the tumour. Scattered small haemorrhages in the transitional zone between the necrotic and the viable part of the tumour were observed in three eyes but large haemorrhages were absent. Ocular media were not affected owing to the low rate of absorption of radiation at 810 nm. TTT did not cause significant scleral damage. Intrascleral tumour cells with a viable appearance were observed in one eye, where the tumour was almost totally necrotic.

CONCLUSION

Results show that TTT has potential as a conservative therapeutic treatment for choroidal melanomas.

A prospective study of infrared coagulation, injection and rubber band ligation in the treatment of haemorrhoids

One hundred patients with non-prolapsing and one hundred with prolapsing haemorrhoids were allocated to receive conventional treatment (CT) by injection sclerotherapy or rubber band ligation, or infrared photocoagulation (IRC). Significantly more patients with nonprolapsing haemorrhoids were symptom free after IRC (81%) than CT (59%) at three months. (Chi2 = 4.4, p = 0.05). There was no significant difference in the outcome at 1 or 4 years. Likewise for prolapsing haemorrhoids, there was no significant difference in the outcome of IRC or CT at 3 months, one or 4 years. However, recurrence of prolapse was more common after IRC (54%) than rubber band ligation (RBL) (27%) at 1 year (Chi2 = 3.46, p less than 0.1). IRC was significantly less painful than CT (p less than 0.001). IRC is a safe, rapid, non-invasive alternative to CT, which is acceptable to the patient and give similar results, though RBL provides more rapid and longer lasting relief from prolapse.

New approaches for the treatment of diabetic macular oedema: recommendations by an expert panel

The current standard therapy for patients with diabetic macular oedema (DME)--focal/grid laser photocoagulation--usually does not improve impaired vision, and many patients lose vision despite laser therapy. Recent approval of ranibizumab by the European Medicines Agency to treat visual impairment due to DME fulfils the previously unmet medical need for a treatment that can improve visual acuity (VA) in these patients. We reviewed 1- and 2-year clinical trial findings for ranibizumab used as treatment for DME to formulate evidence-based treatment recommendations in the context of this new therapy. DME with or without visual impairment should be considered for treatment when it fulfils the Early Treatment Diabetic Retinopathy Study (ETDRS) criteria for clinically significant oedema. For DME with centre involvement and associated vision loss due to DME, monthly ranibizumab monotherapy with treatment interruption and re-initiation based on VA stability is recommended. Laser therapy based on ETDRS guidelines is recommended for other forms of clinically significant DME without centre involvement or when no vision loss has occurred, despite centre involvement. Because these recommendations are based on randomised controlled trials of 1-2 years duration, guidance may need updating as long-term ranibizumab data become available and as additional therapeutic agents are assessed in clinical trials.

Bone ablation with Er:YAG and CO2 laser: study of thermal and acoustic effects

A pulsed Er:YAG laser at 2.94 microns and a superpulsed CO2 laser at 10.6 microns are used to investigate bone ablation applications in otolaryngology. Quantitative measurements of mass removal and the ablation depth of cat skull bone and rat femur are presented with the Er:YAG laser at fluences of 9-117 J/cm2. Histological results show that the minimal thermal injury zone from the edge of the lesion is 5-10 microns. Comparison of the photoacoustic and thermal effects during the ablation process indicates that the temperature rise from the 10.6-microns light was higher than that from the 2.94-microns light but that the photoacoustic wave amplitude produced with the Er:YAG laser was higher than that with the CO2 laser. The fluence used for the efficient ablation of bone tissues produces a photoacoustic wave ranging from 100 to 120 dB. The ear can tolerate this level for a short time period. Results of this study suggest that the Er:YAG laser can be an important surgical tool in otolaryngology.

The course of axons through the retina and optic nerve head

By identifying degenerating axons in tissue specimens from 22 primate eyes, it was possible to demonstrate the normal course of axon fibers. Nerve fiber bundles from a group of retinal ganglion cells travel together with little tendency to disperse laterally. In addition, axons are stratified such that processes from more central ganglion cells are successfully added to the inner strata of the retinal nerve fiber layer. Within and behind the lamina cribrosa, areas of degeneration following retinal photocoagulation were well circumscribed and confined to a group of adjacent axon bundles. This degree of retinotopic organization of axons within the nerve head and retinal fiber layer is believed to be consistent with the premise that isolated lesions within the lamina cribrosa could cause well-organized paracentral scotomas such as those characteristic of early glaucoma.

The efficacy and safety of argon plasma coagulation therapy in Barrett's esophagus

BACKGROUND

Thermoablation is being used to eliminate the metaplastic epithelium of Barrett's esophagus and allow its reversal into squamous epithelium in an acid-controlled environment. This study assessed the efficacy and safety of a new thermoablation technique, argon plasma coagulation.

METHODS

Patients with circumferential Barrett's esophagus 2 to 5 cm long were enrolled. Acid suppression was accomplished with lansoprazole. One-half the circumference of Barrett's mucosa was treated with argon plasma coagulation, and the other half served as an internal control. After macroscopic squamous re-epithelialization occurred, biopsy specimens were obtained from both areas systematically.

RESULTS

Nine patients, all men with a mean age of 51.1 years, completed the study. During 24-hour esophageal pH monitoring a pH less than 4 occurred on average 2.8% of the time with a mean dose of lansoprazole of 70 mg/day. Squamous re-epithelialization developed in treated areas in all 9 patients. Biopsy showed that 7 of 9 patients (77.8%) had squamous re-epithelialization without intestinal metaplasia. Biopsy showed that 2 of 9 patients (22.2%) had squamous re-epithelialization with evidence of underlying intestinal metaplasia. There were no serious complications.

CONCLUSIONS

Argon plasma coagulation in an acid-controlled environment was both efficacious and safe in the treatment of Barrett's esophagus. However, the reappearance of squamous epithelium after therapy did not exclude the presence of underlying intestinal metaplasia.

Age-Related Macular Degeneration

Age-related macular degeneration (AMD) is the leading cause of vision loss in the elderly. AMD is diagnosed based on characteristic retinal findings in individuals older than 50. Early detection and treatment are critical in increasing the likelihood of retaining good and functional vision.

Laser photocoagulation for the treatment of acute peptic-ulcer bleeding. A randomized controlled clinical trial

We tested the hypothesis that therapeutic endoscopy using the Nd:YAG (neodymium:yttrium-aluminum-garnet) laser would benefit patients with acute peptic-ulcer bleeding. Over 43 months, 174 patients with active bleeding (n = 32) or stigmata of recent bleeding (n = 142) due to peptic ulcers were randomly assigned during endoscopy to either standard treatment with laser photocoagulation or therapy without photocoagulation. There were no significant differences in a number of outcomes between the group treated with laser photocoagulation and the control group. Continued bleeding or rebleeding was observed in 22 percent of the laser-treated group and in 20 percent of the control group. Urgent surgery was necessary in 16 percent of the laser-treated patients and in 17 percent of the controls. Laser-treated patients spent a mean of 41 hours in the intensive care unit, and controls spent a mean of 32 hours. The mean hospital stay was 12 days in the laser-treated group and 11 days in the control group. One death occurred in each group. When patients with active bleeding were analyzed separately, there was no significant difference in outcome, even though laser photocoagulation stopped active bleeding in 88 percent of cases. Among patients with visible vessels, rebleeding occurred in 5 of 14 (36 percent) who received laser treatment and 2 of 15 (13 percent) who did not. Laser treatment precipitated bleeding in four patients and duodenal perforation in one. We conclude that Nd:YAG-laser photocoagulation does not benefit patients with acute upper gastrointestinal bleeding from peptic ulcers.