Mini-incision cataract surgery and toric lens implantation for the reduction of high myopic astigmatism in patients with pellucid marginal degeneration.

PURPOSE: To evaluate the clinical outcomes, safety, and efficacy of cataract surgery with the implantation of a toric intraocular lens (IOL) in eyes with stable pellucid marginal degeneration (PMD). METHODS: Eleven eyes (eight patients) diagnosed as stable PMD and cataract underwent mini-incision 2.2 mm cataract surgery followed by the implantation of hydrophobic toric aspheric IOL (AcrySof IQ Toric IOL, Alcon, Fort Worth, TX, USA). Perioperative variables of interest included uncorrected (UDVA) and corrected (CDVA) distance visual acuities, manifest refraction, and corneal topography. Paired samples t-tests were used to analyze preoperative and postoperative visual acuity, astigmatism, and spherical equivalent (SE) parameters. Follow-up was 6 months. RESULTS: The mean CDVA was 0.62±0.26 logMAR preoperatively and 0.07±0.07 logMAR postoperatively. The mean preoperative sphere and cylinder was -3.14±3.58D and -4.84±2.02D, respectively. The mean postoperative manifest refractive sphere and cylinder was -0.30±0.51D and -0.81±1.51D, respectively. There was a significant reduction in refractive astigmatism after toric IOL implantation (P<0.002). The toric IOL axis rotation was <5° in all cases at the final follow-up. CONCLUSIONS: Implantation of hydrophobic toric IOL was a safe and effective surgical procedure to correct mild to moderate stable PMD.

Conservative treatment of keratoconus by riboflavin-uva-induced cross-linking of corneal collagen: qualitative investigation.

PURPOSE: To assess corneal tissue modifications after riboflavin-UVA-induced cross-linking of corneal collagen in patients with progressive keratoconus as well as regeneration of epithelium and subepithelial nerve plexus by in vivo HRT II system confocal microscopy in humans. METHODS: Ten patients with progressive keratoconus were treated by riboflavin-UVA-induced cross-linking of corneal collagen, involving assessment of ultrastructural modifications of the corneal epithelium and subepithelial nerve plexus by HRT II system confocal microscopy. Treatment included instillation of 0.1% riboflavin-20% dextrane solution 5 minutes before UVA irradiation and every 5 minutes for a total of 30 minutes. Radiant energy was 3 mW/cm 2 or 5.4 Joule/cm 2 and the source was dual UVA (370 nm) light-emitting LED. The protocol included the operation followed by antibiotic medication and eye dressing with a soft therapeutic contact lens. Changes in epithelium and subepithelial and stromal nerve plexus were assessed by HRT II system confocal microscopy in vivo. RESULTS: After 5 days of soft contact lens wearing, corneal epithelium has a regular morphology and density. Disappearance of subepithelial stromal nerve fibers was observed in the central irradiated area where, 1 month after the operation, initial reinnervation was microscopically observed. No changes in nerve fibers were observed in the peripheral untreated with a clear lateral transition between the two areas. Six months after the operation, the anterior subepithelial stroma was recolonized by nerve fibers with restoration of corneal sensitivity. CONCLUSIONS: HRT II system confocal microscopy confirms corneal epithelium restore and re-innervation after riboflavin-UVA-induced collagen cross-linking directly in vivo in humans.

Haemophilus influenzae resistance in Latin America: systematic review of surveillance data.

Haemophilus influenzae is a relevant cause of morbidity and mortality among children under 5 years of age in the developing world. In Latin America, H. influenzae type b (Hib) conjugate vaccine and surveillance of H. influenzae antimicrobial susceptibility have been implemented in recent years. We have undertaken a systematic review and a pooled analysis on H. influenzae antimicrobial resistance, including reports of 15 Latin America countries over a 10-year period (1990-2000). We have found that 450 (21.4%) of 2,100 invasive isolates were beta-lactamase producers compared to 145 (14.5%) of 998 isolates of noninvasive isolates (p < 0.05). Ampicillin resistance was detected among 783 (21.9%) of 3,577 invasive isolates compared to 111 (17.2%) of 646 noninvasive strains (p < 0.05). In contrast, 568 (41.9%) of 1,355 noninvasive strains were trimethoprim-sulfamethoxazole (TMP-SMX) resistance against 241 (26.9%) of 897 invasive ones (p < 0.05). Therefore, TMP-SMX resistance was more common in nonsterile fluids than in sterile fluids. Over time, rates of beta-lactamase-producing strains were stable in Brazil and Mexico, whereas rates of TMP-SMX resistance were increasing in Brazil. It is predictable that following the Hib immunization, Latin America countries will be faced with increased nontypeable H. influenzae infection. Although standing by the nontypeable H. influenzae vaccine, in this novel epidemiological scenario of post-Hib vaccination in Latin America settings there is a need to improve H. influenzae resistance monitoring to guide clinicians to choose efficacious antimicrobial therapy.

Time course of exercise capacity, skeletal and respiratory muscle performance after heart-lung transplantation.

Recipients of heart-lung transplantation (HLT) show reduced exercise capacity due to several pre- and postsurgical factors. The aim of this study was to evaluate the time course of exercise capacity, and skeletal and respiratory muscle performance in 11 patients (5 females and 6 males; age (mean +/- SD) 38 +/- 13 yrs) undergoing HLT. All of the patients were admitted to our institution for a rehabilitation programme after surgery, and were followed-up for 18 months. On admission, at discharge after an in-patient rehabilitation programme, and every 6 months, patients underwent evaluation of: lung function values; incremental treadmill exercise, 6 min walking distance (6-MWD); maximal inspiratory and expiratory pressures (MIP and MEP, respectively); and peak torque of isokinetic contraction of leg flexor and extensor muscles (IFX and IEX, respectively). On admission, patients had: reduced lung volumes as assessed by vital capacity (VC) (60 +/- 15% of predicted); reduced exercise capacity as assessed by peak oxygen consumption (V'O2,peak) (40 +/- 12% pred); reduced skeletal and respiratory muscle performance as assessed by IEX, IFX (48 +/- 16 and 28 +/- 12 Newton-metres (N x m), respectively) and by MIP and MEP (54 +/- 21 and 58 +/- 19 cmH2O, respectively). Ten patients completed the rehabilitation programme. At discharge, no significant change in dynamic and static lung volumes was observed. However, nonsignificant increases in MIP, MEP, IEX, IFX, 6-MWD and V'O2,peak were recorded. After 6 and 12 months, indices of skeletal and respiratory muscle function and V'O2, peak improved further, but still remained lower than normal values. We conclude that in patients with heart-lung transplantation, skeletal and respiratory muscle function and exercise performance are reduced after surgery, that they may improve with time but are still less than normal after 18 months.

Healon GV versus Healon in demanding cataract surgery.

This study compared how well two sodium hyaluronate viscoelastics maintained the anterior chamber during cataract surgery in eyes at risk for high vitreous pressure. Patients were divided into two groups based on the sodium hyaluronate used: Healon or Healon GV. Qualitative data were obtained with a digital slide gauge attached to the operating microscope. After capsulorhexis, mean anterior chamber depth (distance of the corneal apex to the iris plane) was significantly greater in the Healon GV group (P = .0012). Subjective intraoperative evaluation by surgeons also favored Healon GV. There was no difference between the groups in postoperative inflammation, corneal edema, intraocular pressure, or visual acuity. Therefore, although the two viscoelastics are equally safe, Healon GV maintains the anterior chamber better during cataract surgery.

Dyspnea on exercise. Pathophysiologic mechanisms.

To evaluate the frequency of the causes of exercise limitation in patients with chronic pulmonary disease and to assess the relationship between the resting pulmonary functional parameters and the degree of exercise dyspnea, we reviewed the data from 88 consecutive stable patients with chronic lung disease (62 COPD, 16 interstitial lung disease [ILD]). In each patient, the intensity of dyspnea was measured by a Borg scale (BS) during an incremental symptom-limited exercise test. COPD patients stopped exercise due to fatigue (46%), dyspnea (36%), cardiac limitation (12%), and peripheral circulatory limitation (6%). ILD patients stopped exercise due to dyspnea (62%), fatigue (25%), and cardiac limitation (12%). In all patients, dyspnea severity increased linearly with exercise intensity as measured as VO2, VE, and VE/MVV. The severity of dyspnea expressed as the slope of the relationship between BS and VE/MVV (DBS/D[VE/MVV]) showed in COPD a significant inverse correlation with VC, FEV1, MIP, and a positive correlation with PaCO2 and VE/MVV at rest. In ILD, DBS/D(VE/MVV) showed a significant inverse correlation with VC, FEV1, TLC, and PaO2 and a positive correlation with VE/MVV at rest. The predicting power of all equations was very low.

The subretinal fluid in retinal detachment. A cytologic study.

Following retinal detachment, subretinal fluid (SRF) fills the neoformed space. Subsequently subretinal and preretinal strands of proliferative tissue begin to form. We have collected the subretinal fluid withdrawn during retinal detachment surgery. We have studied subretinal fluid cytologically to evaluate the number and the type of cells present in the fluid, and by means of transmission electron microscopy. The first cell type to be present in the fluid represented degenerated aspects of pigmented epithelial cells (PECs). Successively, other cell types appeared in the fluid as nerve cells (rods, cones and glial cells), macrophages and well preserved pigmented epithelial cells.