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PURPOSE: To evaluate the causes of laser programming errors in refractive surgery and outcomes in these cases. METHODS: In this multicenter, retrospective chart review, 22 eyes of 18 patients who had incorrect data entered into the refractive laser computer system at the time of treatment were evaluated. Cases were analyzed to uncover the etiology of these errors, patient follow-up treatments, and final outcomes. The results were used to identify potential methods to avoid similar errors in the future. RESULTS: Every patient experienced compromised uncorrected visual acuity requiring additional intervention, and 7 of 22 eyes (32%) lost corrected distance visual acuity (CDVA) of at least one line. Sixteen patients were suitable candidates for additional surgical correction to address these residual visual symptoms and six were not. Thirteen of 22 eyes (59%) received surgical follow-up treatment; nine eyes were treated with contact lenses. After follow-up treatment, six patients (27%) still had a loss of one line or more of CDVA. Three significant sources of error were identified: errors of cylinder conversion, data entry, and patient identification error. CONCLUSION: Twenty-seven percent of eyes with laser programming errors ultimately lost one or more lines of CDVA. Patients who underwent surgical revision had better outcomes than those who did not. Many of the mistakes identified were likely avoidable had preventive measures been taken, such as strict adherence to patient verification protocol or rigorous rechecking of treatment parameters. [ J Refract Surg. 2013;29(5):303–310.]

Although the first attempts at hyperopia correction were made more than 100 years ago, it is only in the past several years that the success of hyperopic refractive surgery has begun to approach the efficacy of myopia surgery. Corneal surgery for the correction of hyperopia includes older lamellar techniques such as automated lamellar keratoplasty and epikeratophakia, and more recently photorefractive keratectomy and laser in situ keratomileusis. The latter two procedures have shown the most success. Using large diameter laser ablations and improved keratomes, laser in situ keratomileusis has become a realistic alternative for corrections of up to 4 or 5 diopters with astigmatic corrections. Laser thermal keratoplasty using the Holmium or diode laser and contact techniques also have gained popularity and shown some potential. Collagen shrinkage procedures are easy to perform and have relatively few complications, but over correction and regression are problems. Crystalline lens surgery and phakic intraocular lenses are being investigated actively and are promising; however, safety issues persist. The surgical treatments of hyperopia present a significant challenge and reward for the ophthalmic surgeon.

Purpose: The purpose of the study is to compare the clinical efficacy and safety of ciprofloxacin ophthalmic solution 0.3% (Ciloxan) with a standard therapy regimen (fortified tobramycin, 1.3%-cefazolin, 5.0%) for treating bacterial corneal ulcers. Methods: This randomized, parallel group, double-masked, multicenter study was conducted in 324 patients at 28 centers in the United States, Europe, and India. Patients were randomized into 2 treatment groups: 160 to ciprofloxacin and 164 to fortified tobramycin-cefazolin. Positive microbiologic cultures were obtained in 188 (58%) of 324 patients. Of these, 176 patients met protocol criteria and were evaluated for treatment efficacy: 82 in the Ciprofloxacin group and 94 in the standard therapy group. The dosing schedule for both treatment groups was 1 to 2 drops of the first study medication (ciprofloxacin or fortified tobramycin) every 30 minutes for 6 hours, then hourly for the remainder of day 1; 1 to 2 drops every hour on days 2 and 3; 1 to 2 drops every 2 hours on days 4 and 5, followed by 1 to 2 drops every 4 hours on days 6 to 14. The second medication (ciprofloxacin or cefazolin) was instilled 5 to 15 minutes after the first drug, following the same dosing frequency. Physician's judgment of clinical success, cure rate, changes in ocular signs, and symptoms and the rate of treatment failures were the primary efficacy criteria. Results: Topical ciprofloxacin monotherapy is equivalent clinically and statistically to the standard therapy regimen of fortified antibiotics. No statistically significant treatment differences were found between ciprofloxacin (91.5%) and standard therapy (86.2%) in terms of overall clinical efficacy ( P = 0.34). Similarly, no differences were noted in resolution of the clinical signs and symptoms ( P > 0.08) or the time to cure ( P = 0.55). The incidence of treatment failures was less in the ciprofloxacin group (8.5%) compared with the standard therapy group (13.8%). Significantly fewer patients treated with Ciprofloxacin reported discomfort than did patients treated with the standard therapy regimen ( P = 0.01). Conclusion: Ciprofloxacin ophthalmic solution 0.3% monotherapy is equivalent clinically and statistically to standard therapy (fortified tobramycin-cefazolin) for the treatment of bacterial corneal ulcers and produces significantly less discomfort.

Purpose: To evaluate the refractive results of 193-nm excimer laser photorefractive keratectomy (PRK) performed on 48 highly myopic eyes in a multicenter study. Methods: A Visx 2015 or 2000 argon-fluoride excimer laser and a single-zone ablation technique were used. Postoperatively, eyes were treated with topical fluoromethalone for up to 5 months. Most eyes were treated with a 6.0- to 6.2-mm beam diameter after undercorrections and increased regression were noted with a 5.5 mm beam in earlier studies. Forty-eight eyes were treated for myopia, which was between −8.0 and −15.25 diopters (D) (spherical equivalent). The mean preoperative refraction was −11.2 D. Retreatment was performed after 6 to 16 months on 11 eyes for undercorrection. All eyes not retreated were followed for at least 12 months. Results: At 6 months, follow-up was available on 47 eyes. Of these eyes, 40% and 64% achieved corrections within 1 and 2 D of attempted correction, respectively. At 1 year, 60% of eyes attained 20/40 visual acuity or better uncorrected. Eleven patients (23%) were retreated between 6 to 16 months for undercorrection and/or regression. After retreatment, 47% and 81% of eyes achieved corrections within 1 and 2 D of attempted correction, respectively. At 1 year, 15% of eyes lost two lines of best-corrected visual acuity, and no eyes lost more than two lines. There was slightly more corneal haze seen in this group compared with the haze seen in patients undergoing PRK for low and moderate myopia. Conclusions: These data show that excimer PRK can correct high amounts of myopia with reasonable stability after 6 months. Excimer PRK is an effective surgical treatment of severe myopia, but long-term follow-up is still needed to assess the stability of its effect.

As part of a Phase III clinical trial, photorefractive keratectomy using the VISX 2015 193 nm excimer laser was performed on 91 sighted eyes of 91 patients. Preoperative refractive errors (spherical equivalent) ranged from -1.00 diopters (D) to -7.50 D (mean -4.11 D ± 1.43 D). At six months, average residual refractive error was 0.02 D ± 0.64 D (range -2.21 D to +1.38 D). Ninety-three percent of eyes were within 1.00 D of attempted correction, 93% had uncorrected visual acuity of 20/40 or better, and 72% achieved uncorrected visual acuity of 20/25 or better. All patients returned to their best corrected visual acuity within one line of their preoperative best corrected visual acuity. Photorefractive keratectomy with the 193 nm excimer laser appears to be useful in reducing low to moderate myopia.

Aims Ophthalmic laser treatments are discouraged in patients with implantable pulse generators (IPGs, pacemakers) and implantable cardioverter defibrillators (ICD) due to potential effects of the electromagnetic interference (EMI) emitted by ophthalmic laser systems. We assessed the effects of EMI generated by ophthalmic laser systems and laser discharge on IPG and ICD function. Methods and results Two implantable devices, one Victory dual-chamber IPG (St Jude Medical, Minneapolis, MN, USA) and one Atlas II + dual-chamber ICD (St Jude Medical), were consecutively placed in a simulated thoracic chamber and exposed to three ophthalmic laser systems: the VISX Star S4 Excimer Laser, Lumenis Selecta II 532 neodymium-doped yttrium aluminium garnet (Nd:YAG) laser, and Ellex Ultra Q 1064 nm Nd:YAG laser. For each laser system, the apparatus was placed in the relative position of a patient while common laser procedures were delivered to a plastic object. Device pacing parameters were programmed to the highest possible sensitivity settings. The pacing and defibrillation function of the implantable devices, including electrograms, were continuously monitored. The EMI emitted from ophthalmic lasers did not lead to oversensing, inappropriate therapy, or change in the programming of the implantable cardiac devices. Manufacturing electrical tests performed on both devices showed that the cardiac devices continued to meet all the specifications for proper device function. Conclusion The St Jude Medical Victory IPG and Atlas II + ICD were not affected by the EMI emitted by the ophthalmic laser systems.

BACKGROUND: Following excimer laser photorefractive keratectomy, patients experience significant ocular pain until corneal reepithelialization. Despite the use of cold compresses, bandage soft contact lenses, cycloplegics, narcotics, and topical corticosteroids, the pain has not been adequately controlled in many patients. METHODS: A randomized, double-masked, parallel-group study of diclofenac sodium 0.1% ophthalmic solution and its placebo vehicle was evaluated. Patients undergoing excimer myopic photorefractive keratectomy on their second eye were admitted overnight. Postoperative procedures included two drops of diclofenac or placebo immediately after surgery and then qid until reepithelialization, topical tobramycin (qid), 0.1% fluorometholone (q2h), cycloplegics, and a disposable soft contact lens. Thirty-two patients (diclofenac= 16, placebo= 16) were evaluated from + 30 minutes to +96 hours by several types of questionnaires. RESULTS: Most patients who received placebo experienced pain, starting within 1 hour, peaking at 4 to 6 hours and lasting 36 to 48 hours. The diclofenac-treated patients rarely experienced the early peak in pain, had less pain overall until 72 hours postoperatively, and experienced significantly less photophobia and burning/stinging. Significantly fewer patients on diclofenac required oral narcotics. Three patients (diclofenac =2, placebo= 1) developed corneal infiltrates, the etiology of which is not known. In a separate study we conducted, there was no difference in epithelial healing times between the diclofenac-treated eyes and those not receiving the drug. CONCLUSIONS: Diclofenac appears to significantly reduce the ocular pain following excimer photorefractive keratectomy. (Refract Corneal Surg. 1993;9:425-436.) RÉSUMÉ INTRODUCTION: Les patients éprouvent une douleur oculaire significative après la kératectomie photorefractive au laser excimer jusqu'à la ré-epithélialisation cornéenne. Malgré l'emploi de compresses froides, le port de lentilles de contact, la cycloplégle, l'utilisation de narcotiques, et de corticoïdes, la douleur ne fut pas contrôlée chez un grand nombre de patients.

Six patients underwent excimer laser refractive keratectomy for the correction of myopia. All eyes, with the exception of patient 6, who underwent a previous failed epikeratophakia procedure and subsequent removal of the lenticule, had normal baseline ophthalmologic evaluations and best corrected visual acuities of 20/25 or better. Spherical equivalents ranged between -5.50 and -12.00 diopters. Under topical and peribulbar anesthesia, the central corneal epithelium was removed. The delivery system of the laser was programmed to ablate corrections onto the central 5.0 mm of the cornea that would result in approximate emetropia. Moderate fluctuation of refractive and topographic parameters was noted during the period of epithelial healing and remodeling. At the 12th postoperative week, five of the corneas were clear on biomicroscopic evaluation with best corrected acuities of 20/20. The final patient, who was noncompliant in the use of topical corticosteroid therapy, developed a central, 2-mm opacity and resulting best corrected acuity of 20/40. Overall, the group demonstrated that myopic excimer laser photorefractive keratectomy is consistent with good wound healing, insignificant corneal scarring, a stable refractive correction, and excellent visual acuity. [Refractive and Corneal Surgery 1990;6:329-334.]

As part of a clinical trial, photorefractive keratectomy using the VISX 2015 193-nm excimer laser was performed on 91 healthy eyes of 91 patients. Preoperative refractive errors (spherical equivalent) ranged from -1.00 to -7.50 diopters (mean, -4.16 +/- 1.41 diopters). No patient had more than 1 diopter of refractive astigmatism. Six months postoperatively, the average residual refractive error was +0.09 +/- 0.63 diopters (range, -2.13 to +1.63 diopters). Correction within 1 diopter of that attempted was attained in 85 eyes (93%). Uncorrected visual acuity of 20/40 or better was attained in 86 eyes (95%) and was 20/25 or better in 67 eyes (74%). At one year, follow-up information was available on 85 eyes of 85 patients. The average residual refractive error was -0.15 +/- 0.65 diopters (range, -2.50 to +1.63 diopters). Correction within 1 diopter of that attempted was attained in 85 eyes (93%). Uncorrected visual acuity was 20/40 or better in 83 eyes (98%) and was 20/25 or better in 68 eyes (80%). One patient lost three lines of best-corrected visual acuity because of corneal haze, dropping from 20/15 to 20/30, whereas all other patients returned to best-corrected visual acuity within one line of their preoperative best-corrected visual acuity. Photorefractive keratectomy with the 193-nm excimer laser appears to be a useful treatment modality for the reduction of mild to moderate myopia.

Severe postoperative pain has been a significant complication of excimer laser photorefractive keratectomy (PRK). We report herein the dramatic effect of topical diclofenac sodium (Voltaren Ophthalmic) for relieving patient discomfort following PRK. We performed a retrospective analysis of 20 consecutive patients who had undergone bilateral PRK for myopia as part of a phase III US Food and Drug Administration study (the second eye was operated on 6 months after the first). Initially treated eyes were generally the more myopic of the two. Following PRK using topical anesthesia, one drop each of tobramycin, 0.25% scopolamine, and 0.1% fluorometholone were administered and a disposable contact lens was placed on the eye. The patients were instructed to use the tobramycin four times a day and the 0.1% fluorometholone every 2 hours while awake. The regimen was identical in the second eye with the exception ofthe addition of 0.1% diclofenac four times a day.

In Reply. —We appreciate Dr Adamson's interest in our report on excimer PRK in myopia. We concur that more sophisticated and extensive methods of contrast sensitivity testing would be desirable in evaluating visual function after refractive surgery. Such studies are now under way in our phase III patients. Patients included in this preliminary group were myopic and were capable of wearing a contact lens in the fellow eye for at least 6 months. All patients had normal results of ophthalmic examinations except one phase II patient who had undergone prior epikeratophakia (patient 3). Contrast sensitivity testing was performed for all patients using standard conditions with day vision illumination. Each eye was tested separately, the right eye being tested first. The Multivision Contrast Tester 8000 was used. Spacial frequencies of 1.5, 3, 6, 12, and 18 cycles per degree were used for testing. Patients were required to respond and guess even

Excimer photorefractive keratectomy was performed at three centers on 16 highly myopic eyes (8 diopters [D] or more) and followed up for 6 months. Ablation depths ranged from 137 to 230 microns. The preoperative spherical equivalent of myopia ranged from -8.62 D to -14.50 D (mean +/- SD, -11.57 +/- 1.62 D). Six months after surgery, the mean refraction (spherical equivalent) was -0.90 +/- 2.13 D. Eleven of 16 eyes achieved refractions within 2 D of that attempted. All eight patients at one site were treated with a maximum-beam diameter of 6.0 mm and were corrected to within 2 D of that attempted, and all were 20/40 or better uncorrected. Three of eight eyes at the other two sites were treated with a 5.5- or 5.6-mm maximum-beam diameter, which achieved corrections within 2 D of that attempted. The epithelium healed within 3 to 4 days, and there were no erosions. Mild subepithelial reticular haze, similar to that seen with excimer photorefractive keratectomy for lower myopia, was seen in all patients, with two patients experiencing more significant corneal haze. This peaked at 3 to 6 weeks and then gradually diminished. All but two patients had a return of their best corrected preoperative visual acuity to within one Snellen line at 6 months. This preliminary study shows excimer photorefractive keratectomy to be a promising surgical treatment for patients with higher myopia.

Photorefractive keratectomy was performed at three centers using the 193-nm excimer laser on 31 sighted myopic eyes. Preoperative refractive errors (spherical equivalent) ranged from -12.00 to -4.00 diopters (D) (mean, -6.49 +/- 1.75 D). Peribulbar anesthesia, a 5.2- to 6.0-mm beam diameter, and topical corticosteroids were used for up to 6 months after surgery. The epithelium healed within 3 to 4 days, and all patients returned to their best corrected visual acuity within 1 line of their preoperative acuity. There was minimal subepithelial reticular haze, peaking at 3 weeks and diminishing over the next 3 to 4 months, which was not felt to be visually significant. At 6 months, the average residual refractive error was -1.85 +/- 2.5 D. Sixty-eight percent of eyes were corrected within 2 D and 55% within 1 D of attempted correction. There was no significant change in astigmatism, contrast sensitivity, corneal sensation, or endothelial cell counts. This preliminary work shows that photorefractive keratectomy has promise in the reduction of moderate myopia.

• Phototherapeutic keratectomy using a 193-nm excimer laser was performed at four centers on 33 sighted patients with corneal opacity and/or irregular astigmatism. Pathologic conditions included anterior stromal and superficial scarring from postinfectious and posttraumatic causes, including inactive herpes simplex virus, anterior corneal dystrophies, recurrent erosions, granular dystrophy, and band keratopathy. Most patients received peribulbar anesthesia and underwent removal of the epithelium prior to laser ablation. A majority of patients had a reduction in the amount of corneal scarring and approximately half had improved visual acuity. No intraocular reaction or changes in endothelial counts were seen, and some patients avoided the need for penetrating keratoplasty. Reepithelialization usually occurred within 4 or 5 days and we noted no significant scarring secondary to use of the laser. It was difficult to eliminate preexisting irregular astigmatism despite the use of surface modulators, such as methylcellulose. A hyperopic shift secondary to corneal flattening was encountered in approximately 50% of the patients. A combination of myopic ablation, followed immediately by a secondary hyperopic steepening, may minimize this refractive change. The 193-nm excimer laser is an effective new tool in the treatment of selected patients with superficial corneal opacity from a variety of conditions.

• Several diagnostic signs of Acanthamoeba keratitis have been reported recently. We treated three patients who developed a dendritiform epithelial pattern seen early in the course of Acanthamoeba keratitis that likely represents epithelial infection by Acanthamoeba before any stromal involvement. In these three cases, the early diagnosis of Acanthamoeba keratitis coupled with wide epithelial debridement and medical therapy proved effective in eradicating the protozoan. In two additional cases, Acanthamoeba keratitis was not diagnosed until significant stromal involvement was present. Medical therapy was effective in eradicating the organism in one case, although penetrating keratoplasty was necessary for visual rehabilitation. In the other case, medical therapy was ineffective, as corneal perforation resulted and Acanthamoeba cysts were demonstrated by fluorescent staining in the host corneal button.

Mice homozygous for the mutation "nude" (nu/nu) are athymic and lack thymus-dependent lymphocytes. Heterozygote (nu/+) controls, which are phenotypically and immunologically normal, and (nu/nu) mice were infected with 1.0 times 10-6 colony-forming units of Phipps strain BCG. In the spleens of nu/+ mice, there was a progressive increase in number of BCG up to the second week, followed by a gradual decline. However, in the nu/nu mice, BCG growth was gradual and continuous until termination of the experiment at 5 weeks. In the lung, significant differences were not noted until after the second week, at which time the nude mice showed a rapid increase (of more than 2 log10) in the number of BCG. However, the number of BCG was not significantly greater in the livers of either group. Changes in the normal histology of the lung included a massive influx of monocytes during the first 2 weeks which peaked at day 21. In the lungs of the nu/+ mice by day 28, there was considerable granuloma formation consisting of monocytes and small lymphocytes. However, in the lungs of nu/nu animals, the granulomas were made up primarily of monocytes with a lack of small lymphocytes. Acid-fast stains confirmed the presence of large numbers of organisms in the macrophages of nu/nu mice, with gradual destruction of these phagocytic cells.

Three parameters of macrophage function: random migration, chemotaxis, and pinocytosis, were studied in the guinea pig after administration of Corynebacterium parvum, methanol-extraction residue of BCG, and levamisole (LMS), a synthetic anthelmintic. Macrophage migration studies were performed with a modified Boyden chamber. Pinocytosis was assessed by the uptake of colloidal 198Au. After ip administration, each of the three immunostimulators induced an increase in macrophage chemotactic responsiveness and, to a lesser extent and duration, in random motility. Kinetic, dose-response, and time course data for the effect of each agent on macrophage movement were explored. LMS was the most effective stimulator of macrophage activation, which occurred earlier and persisted longer than it did with the other agents. Macrophages from animals receiving each of the agents showed enhanced pinocytosis. Measurement of macrophage random migration, chemotaxis, and pinocytosis appeared to provide a rapid and quantitative assessment of several parameters of macrophage function and, when studied with other immunologic parameters, may provide useful tools for the evaluation of potential immunoadjuvants.

Subcutaneous footpad injection of BCG causes a marked augmentation of popliteal lymph node plaque-forming cell (PFC) responses to DNP-derivatized hemocyanin and to sheep red blood cells, both T-dependent antigens, but not to DNP-derivatized Ficoll, a T-independent antigen. This augmentative effect occurs in normal thymus-bearing heterozygous (nu/+) mice, but not in congenitally athymic nude mice (nu/nu). In contrast, intravenous injection of BCG causes a suppressed splenic PFC response to subsequently administered T-dependent or T-independent antigens in both nude and nu/+ mice. BCG's augmenting effect on the lymph node appears to be mediated by a T-helper cell. BCG's suppressive effect in the spleen is not attributable to T cells. The actual mechanism of the BCG-mediated suppressive splenic effect remains incompletely defined at present.

• A 16-year-old boy had a central retinal artery occlusion and was subsequently diagnosed as a hemizygote with Fabry's disease. The typical ocular manifestations in males with this inborn error of glycosphingolipid metabolism include whorl-like corneal epithelial infiltrates, retinal and conjunctival vessel tortuosity, and lenticular changes. The present case represents the first report of a retinal artery occlusion as an ocular complication of Fabry's disease.

Macrophage migration inhibition factor (MIF), a soluble mediator of delayed hypersensitivity, was assayed for in the aqueous humor of rabbits undergoing corneal graft rejection. Penetrating and interlamellar xenografts and interlamellar allografts were performed in rabbits, and aqueous humor early in the course of xenograft and allograft rejection, and MIF activity was present during the course of the active rejection. This activity returned to near normal after the active rejection resolved. No significant MIF activity could be measured during the nonspecific inflammations produced by alkali burns, multiple paracenteses, intracorneal clove oil, mechanical debriding of the endothelium.

• A 38-year-old man with hypogammaglobulinemia and pulmonary Nocardia asteroides infection developed an intraocular Nocardia infection. The diagnosis was confirmed by examination of a specimen removed at pars plana vitrectomy. The chorioretinal infection in one eye resolved partially, with no organisms visible on histopathologic examination of the globe at autopsy. One month before the patient's death from disseminated nocardial infection, the previously uninvolved right eye developed a new metastatic nocardial chorioretinal lesion. This lesion rapidly progressed in size until the patient's death and showed on postmortem examination the presence of organisms characteristic of N asteroides . ( Arch Ophthalmol 95:1415-1418, 1977)

We present the ocular manifestations in a series of 37 hemizygous male and 25 heterozygous female patients with Fabry's disease. The ocular findings typically do not impair vision, but are unique and diagnostic. Whorl-like corneal deposits were seen in almost all patients and were more severe in the heterozygotes. The lens showed cream-colored anterior capsular deposits, sometimes in striking "propeller" distribution, in one third of the hemizygotes, and in none of the heterozygotes. A faint but unique posterior capsular opacity with a branching radial pattern was seen in 37% of the hemizygotes and 14% of the heterozygotes. Conjunctival vessel aneurysmal dilations and retinal vessel tortuosity were both more frequent and severe in the hemizygotes. Severe visual loss occurred in two hemizygotes as a result of unilateral total central artery occlusions.

An immunosuppressed mouse model was devised to test the effects of immunopotentiators on the prevention of bacterial and fungal infections. The effects of BCG and Corynebacterium were tested against Staphylococcus aureus and Candida albicans infection. The effect of methanol-extraction residue (MER-BCG) was tested against S. aureus septicemia. CDF mice were given various doses of BCG, 1.0 mg of C. parvum, or 0.5 mg of MER intraperitoneally at varying intervals before injection of an intravenous bacterial challenge. Four days before challenge, 300 mg of cyclophosphamide per ml was given intraperitoneally. BCG (106 colony-forming units) reduced mortality due to S.aureus at pretreatment intervals of 3, 7, 14, and 28 days. Isonicotinic acid hydrazide treatment elimated the protective effect of the live BCG. C. parvum was as effective as BCG against S. aureus septicemia when given 3 days before infection, but lost most of its protective effect after that time. MER protected at doses as small as 0.25 mg when given 25 days prior to challenge. Both BCG and C. parvum exerted a protective effect against Candida albicans infection.

The abilities of six strains of Mycobacterium bovis strain BCG to replicate in vivo and to cause spleen enlargement in the CDF 1 male mouse were compared. The strains were grown in synthetic medium and harvested soon after complete pellicles were produced on liquid medium. In addition, two freeze-dried commercially available preparations were tested. The comparisons were made on the basis of injecting equal numbers of colony-forming units. Strain differences were marked. The Brazil strain was most effective in stimulating spleen enlargement, and the Japan strain was the least effective. This correlated with the number of colony-forming units isolated from the spleen.

Three patients with benign intracranial hypertension ([BIH], or pseudotumor cerebri) had verified increased CSF pressure and unilateral papilledema. One patient had slowly progressive loss of visual acuity until unilateral optic nerve sheathotomy was performed. One patient had spontaneous venous pulsation in the unaffected eye. The diagnosis of BIH must be considered even in the absence of bilateral papilledema. (JAMA1983;250:2346-2347)