Effect of post crosslinking haze on the repeatability of Scheimpflug-based and slit-scanning imaging devices.

PURPOSE: The aim of this study was to analyze the effect of postcollagen crosslinking (CXL) haze on the measurement and repeatability of pachymetry and mean keratometry (Km) of four corneal topographers. MATERIALS AND METHODS: Sixty eyes of sixty patients with progressive keratoconus who had undergone accelerated CXL (ACXL) underwent imaging with a scanning slit imaging device (Orbscan II) and three Scheimpflug imaging devices (Pentacam HR, Sirius, and Galilei). Post-ACXL haze was measured using the densitometry software on the Pentacam HR. Readings of the thinnest corneal thickness (TCT) and Km from three scans of each device were analyzed. Effect of haze on the repeatability of TCT and Km measurements was evaluated using regression models. Repeatability was assessed by coefficient of variation. RESULTS: Corneal densitometry in different zones affected the repeatability of TCT measurement of Orbscan (P < 0.05) significantly but not the repeatability of TCT with Pentacam HR and Sirius (P = 0.03 and 0.05, respectively). Km values were affected by haze when measured with the Pentacam HR (P < 0.05). The repeatability of Km readings for all devices was unaffected by haze. In the anterior 0-2 mm and 2-6 mm zone, TCT (P = 0.43 and 0.45, respectively), Km values (P = 0.4 and 0.6, respectively), repeatability of TCT (P = 0.1 in both zones), and Km (P = 0.5 and 0.1, respectively) with Galilei were found to be the most reliable. CONCLUSION: Galilei measurements appear to be least affected by post-ACXL haze when compared with other devices. Hence, topography measurements in the presence of haze need to be interpreted with caution.

Corneal Dendritic Cell Density Is Associated with Subbasal Nerve Plexus Features, Ocular Surface Disease Index, and Serum Vitamin D in Evaporative Dry Eye Disease.

Dry eye disease (DED) has evolved into a major public health concern with ocular discomfort and pain being responsible for significant morbidity associated with DED. However, the etiopathological factors contributing to ocular pain associated with DED are not well understood. The current IVCM based study investigated the association between corneal dendritic cell density (DCD), corneal subbasal nerve plexus (SBNP) features, and serum vitamin D and symptoms of evaporative dry eye (EDE). The study included age and sex matched 52 EDE patients and 43 heathy controls. A significant increase in the OSDI scores (discomfort subscale) was observed between EDE (median, 20.8) and control (median, 4.2) cohorts (P < 0.001). Similarly, an increase in DCD was observed between EDE (median, 48.1 cells/mm(2)) patients and controls (median, 5.6 cells/mm(2)) (P < 0.001). A significant decrease in SBNP features (corneal nerve fiber length, fiber density, fiber width, total branch density, nerve branch density, and fiber area) was observed in EDE patients with OSDI score >23 (P < 0.05). A positive correlation was observed between DCD and OSDI discomfort subscale (r = 0.348; P < 0.0003) and SBNP features. An inverse correlation was observed between vitamin D and OSDI scores (r = -0.332; P = 0.0095) and DCD with dendritic processes (r = -0.322; P = 0.0122). The findings implicate DCD, SBNP features, and vitamin D with EDE symptoms.

An In Vivo Confocal Microscopic Study of Corneal Nerve Morphology in Unilateral Keratoconus.

Purpose. To study the corneal nerve morphology and its importance in unilateral keratoconus. Materials and Methods. In this prospective cross-sectional study, 33 eyes of 33 patients with keratoconus in one eye (Group 3) were compared with the other normal eye of the same patients (Group 2) and 30 eyes of healthy patients (Group 1). All patients underwent detailed ophthalmic examination followed by topography with Pentacam HR and in vivo confocal microscopy (IVCM). Five images obtained with IVCM were analyzed using an automated CCmetrics software version 1.0 for changes in subbasal plexus of nerves. Results. Intergroup comparison showed statistically significant reduction in corneal nerve fiber density (CNFD) and length (CNFL) in Group 3 as compared to Group 1 (p < 0.001 and p = 0.001, resp.) and Group 2 (p = 0.01 and p = 0.02, resp.). Though corneal nerve fiber length, diameter, area, width, corneal nerve branch density, and corneal total branch density were found to be higher in decentered cones, only the corneal nerve branch density (CNBD) was found to be statistically significant (p < 0.01) as compared to centered cones. Conclusion. Quantitative changes in the corneal nerve morphology can be used as an imaging marker for the early diagnosis of keratoconus before the onset of refractive or topography changes.

Bacterial colonization increases daily symptoms in patients with chronic obstructive pulmonary disease.

RATIONALE: Respiratory pathogens are frequently isolated from the airways of patients with chronic obstructive pulmonary disease (COPD) in the absence of an exacerbation. This bacterial "colonization" by potential pathogens is associated with host inflammatory and immune responses, which could increase respiratory symptoms. OBJECTIVES: To study whether bacterial colonization impacts daily respiratory symptoms in COPD. METHODS: In a longitudinal prospective observational study of COPD, patients recorded daily symptoms electronically on the Breathlessness, Cough, and Sputum Scale (BCSS). Sputum cultures and quantitative polymerase chain reaction (PCR) were performed every 2 weeks. The relationship of BCSS and bacterial colonization was analyzed with generalized linear mixed effects models, after controlling for exacerbations, weather conditions, lung function, and demographic variables. MEASUREMENTS AND MAIN RESULTS: A total of 41 patients recorded daily symptoms for 12,527 days. The average BCSS score was higher during the periods of colonization, determined by sputum culture with one or more of the following pathogens: nontypeable Haemophilus influenzae, Moraxella catarrhalis, Streptococcus pneumoniae, and Pseudomonas aeruginosa, compared to periods without colonization (5.28 vs. 4.46; P = 0.008) after controlling for confounding variables. The finding did not change when colonization was defined by quantitative PCR (average BCSS, 4.77 vs. 4.25; P = 0.006). Sputum IL-8 levels were elevated with bacterial colonization. CONCLUSIONS: Even in the absence of clinical exacerbation, colonization by bacterial pathogens in COPD was associated with a clinically significant moderate increase in daily symptoms, likely mediated by increased airway inflammation. Novel therapies that decrease bacterial colonization in COPD could improve daily symptoms and quality of life.

Pulmonary emergencies: pneumonia, acute respiratory distress syndrome, lung abscess, and empyema.

This article describes the clinical presentation of pneumonia, acute respiratory distress syndrome, lung abscess, and empyema: life-threatening infections of the pulmonary system. The etiology and risk factors for each of these conditions are described, diagnostic approaches are discussed, and evidence-based management options are reviewed.

Haemophilus influenzae infections in the H. influenzae type b conjugate vaccine era.

The widespread use of Haemophilus influenzae type b (Hib) conjugate vaccines has nearly eradicated invasive Hib disease where the vaccines are used. This success was accompanied by a shift in capsular serotypes of invasive H. influenzae disease, with nontypeable strains replacing type b strains as the most common bloodstream isolate, but there is no convincing evidence of a true increase in the incidence of non-serotype b invasive infections. H. influenzae causes predominantly mucosal infections. The introduction of vaccines for otitis media and global shifts in antimicrobial susceptibility emphasize the importance of continued surveillance of H. influenzae colonization and disease patterns.

Combined hepatocholangiocarcinoma: case-series and review of literature.

BACKGROUND AND AIM: Combined hepatocholangiocarcinoma (CHCC) is an infrequent primary hepatic malignancy with no clearly defined diagnostic criteria, poorly studied natural history, and no guidelines regarding therapy. In this study we attempted to address this need and review our experience. METHODS AND RESULTS: We performed a retrospective review of all CHCC cases at our institute over the last 10 yr. Eight cases were identified; histological and immunohistochemical criteria used for diagnosis were defined. Patients characteristics were: median age 65 yr (range 47-80); five females; risk factors-cholelithiasis (n = 4) and cirrhosis due to chronic viral hepatitis B and C (n = 1). Abdominal pain (n = 6), hepatomegaly (n = 4), and elevated CA 19-9 >40 U/mL (n = 4/5) were frequent. Early TNM stage (I and II) compared with advanced disease (III and IV) correlated with higher overall survival on univariate analyses [37 and 6 mo respectively (p = 0.011)]. Median overall survival was significantly higher in patients who underwent potentially curative resection (23 mo, range 4-48+) compared with patients who underwent non-surgical therapies such as transcatheter arterial chemoembolization and chemotherapy (2 mo, range 1-8) (p = 0.0357, one-sided exact log-rank test). CONCLUSIONS: Chronic inflammation and cirrhosis may play a role in pathogenesis of CHCC. Surgical resection and early stage at diagnosis predict longer survival.