Tear Mediators in Corneal Ectatic Disorders

PurposeTo compare the concentrations of 11 tear mediators in order to reveal the biochemical difference between pellucid marginal degeneration (PMD) and keratoconus (KC).MethodsWe have designed a cross-sectional study in which patients with corneal ectasia based on slit-lamp biomicroscopy and Pentacam HR (keratometry values (K1, K2, Kmax), astigmatism, minimal radius of curvature (Rmin), corneal thickness (Apex and Min), indices (surface variation, vertical asymmetry, keratoconus, central keratoconus, height asymmetry and decentration)) were enrolled. Eyes of keratoconic patients were similar to the PMD patients in age and severity (K2, Kmax and Rmin). Non-stimulated tear samples were collected from nine eyes of seven PMD patients, 55 eyes of 55 KC patients and 24 eyes of 24 healthy controls. The mediators’ (interleukin -6, -10, chemokine ligand 5, -8, -10, matrix metalloproteinase (MMP) -9, -13, tissue inhibitor of metalloproteinases (TIMP)-1, tissue plasminogen activator, plasminogen activator inhibitor, nerve growth factor) concentrations were measured using Cytometric Bead Array.ResultsMMP-9 was the only mediator which presented relevant variances between the two patient groups (p = 0.005). The ratios of MMP-9 and TIMP-1 were 2.45, 0.40 and 0.23 in PMD, KC and the controls, respectively.ConclusionAs far as we are aware, this is the first study that aims to reveal the biochemical differences between PMD and KC. Further studies of biomarkers to investigate the precise role of these mediators need to be defined, and it is important to confirm the observed changes in a larger study to gain further insights into the molecular alterations in PMD.     

Corneal Sensitivity and Dry Eye Symptoms in Patients with Keratoconus

Purpose

To investigate corneal sensitivity to selective mechanical, chemical, and thermal stimulation and to evaluate their relation to dry eye symptoms in patients with keratoconus.

Methods

Corneal sensitivity to mechanical, chemical, and thermal thresholds were determined using a gas esthesiometer in 19 patients with keratoconus (KC group) and in 20 age-matched healthy subjects (control group). Tear film dynamics was assessed by Schirmer I test and by the non-invasive tear film breakup time (NI-BUT). All eyes were examined with a rotating Scheimpflug camera to assess keratoconus severity.

Results

KC patients had significatly decreased tear secretion and significantly higher ocular surface disease index (OSDI) scores compared to controls (5.3±2.2 vs. 13.2±2.0 mm and 26.8±15.8 vs. 8.1±2.3; p<0.001). There was no significant difference in NI-BUT between the two groups (KC: 9.8±4.8 vs. control: 10.7±3.8; p>0.05). The mean threshold for selective mechanical (KC: 139.2±25.8 vs. control: 109.1±24.0 ml/min), chemical (KC: 39.4±3.9 vs. control: 35.2±1.9%CO₂), heat (KC: 0.91±0.32 vs. control: 0.54±0.26 Δ°C) and cold (KC: 1.28±0.27 vs. control: 0.98±0.25 Δ°C) stimulation in the KC patients were significantly higher than in the control subjects (p<0.001, for all parameters). No correlation was found between age and mechanical, chemical, heat or cold thresholds in the patients with KC (p>0.05), whereas in the control subjects both mechanical (r = 0.52, p = 0.02), chemical (r = 0.47, p = 0.04), heat (r = 0.26, p = 0.04) and cold threshold (r = 0.40, p = 0.03) increased with age. In the KC group, neither corneal thickness nor tear flow, NI-BUT or OSDI correlated significantly with mechanical, chemical, heat or cold thresholds (p>0.05 for all variables).

Conclusions

Corneal sensitivity to different types of stimuli is decreased in patients with keratoconus independently of age and disease severity. The reduction of the sensory input from corneal nerves may contribute to the onset of unpleasant sensations in these patients and might lead to the impaired tear film dynamics.     

兔泪腺摘除后的泪液分泌及其角膜上皮的形态学改变

目的观察摘除泪腺后,兔泪液S1T值、角膜荧光素染色和虎红染色的变化及其角膜上皮超微结构的变化,评估兔干眼症模型的建立。方法摘除兔泪腺和Harder氏腺,比较泪腺摘除前后S1T、角膜荧光素染色和虎红染色分值的变化,并在透射电镜下观察角膜上皮形态学的变化。结果泪腺摘除后平均S1T值(15.88±6.29mm/5min)低于摘除前的平均S1T值(20.25±5.52mm/5min),差别有统计学意义(P=0.0062)。平均角膜荧光素染色和虎红评分(分别为8.22±1.99和7.67±0.87)明显高于摘除前(分别为0.22±0.44和0.67±0.5),差别有统计学意义(两组均P<0.0001)。以上3个检查指标的变化说明摘除泪腺后出现水液性泪液分泌缺乏,导致角膜上皮点状剥脱,干燥及坏死。在形态学上泪腺摘除前后的角膜上皮也发生了明显的改变,透射电镜检查发现液化的表层上皮细胞,表层细胞膜破裂。以上的改变均符合干眼症的特征。结论摘除兔泪腺和Harder氏腺后兔泪液分泌减少,角膜上皮坏死,能有效形成泪液缺乏型干眼模型。     

Evaluation of Intereye Corneal Asymmetry in Patients with Keratoconus. A Scheimpflug Imaging Study

Purpose

To assess the correlation between keratoconus severity and intereye asymmetry of pachymetric data and posterior elevation values and to evaluate their combined accuracy in discriminating normal corneas from those with keratoconus.

Methods

This study included 97 patients: 65 subjects with bilateral normal corneas (NC) and 32 with keratoconus (KC). Central corneal thickness (CCT), thinnest corneal thickness (ThCT) and posterior elevation (PE) at the thinnest point of the cornea were measured in both eyes using Scheimpflug imaging. Intereye asymmetry and its correlation with keratoconus severity were calculated for each variable. The area under the receiver operating characteristic curve (AUROC) was used to compare predictive accuracy of different variables for keratoconus.

Results

In normal eyes, intereye differences were significantly lower compared with the keratoconus eyes (p<0.001, for CCT, ThCT and PE). There was a significant exponential correlation between disease severity and intereye asymmetry of steep keratometry (r² = 0.55, p<0.001), CCT (r² = 0.39, p<0.001), ThCT (r² = 0.48, p<0.001) and PE (r² = 0.64, p<0.001). After adjustment for keratoconus severity, asymmetry in thinnest pachymetry proved to be the best parameter to characterize intereye corneal asymmetry in keratoconus. This variable had high accuracy and significantly better discriminating ability (AUROC: 0.99) for KC than posterior elevation (AUROC: 0.96), ThCT (AUROC: 0.94) or CCT (AUROC: 0.92) alone.

Conclusions

There is an increased intereye asymmetry in keratometry, pachymetry and posterior corneal elevation values in keratoconic patients compared to subjects with normal corneas. Keratoconus patients with more severe disease are also more asymmetric in their disease status which should be taken into account during clinical care.     

Early Changes in Ocular Surface and Tear Inflammatory Mediators after Small-Incision Lenticule Extraction and Femtosecond Laser-Assisted Laser In Situ Keratomileusis

Purpose

To characterize the early ocular-surface changes or tear inflammatory-mediators levels following small-incision lenticule extraction (ReLEx smile) and femtosecond laser-assisted laser in situ keratomileusis (FS-LASIK).

Methods

Forty-seven myopic subjects were recruited for this prospective study. Fifteen underwent ReLEx smile and thirty-two underwent FS-LASIK. Corneal fluorescein (FL) staining, tear break-up time (TBUT), Schirmer I test (SIT), ocular surface disease index (OSDI) and central corneal sensitivity were evaluated in all participants. Tears were collected and analyzed for interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), nerve growth factor (NGF) and intercellular adhesion molecule-1 (ICAM-1) levels using multiplex magnetic beads. All measurements were preformed preoperatively and 1 day, 1 week, 1 month and 3 months postoperatively.

Results

FL scores in ReLEx smile group were lower than those of FS-LASIK group 1 week postoperatively (P = 0.010). Compared to the FS-LASIK group, longer TBUT were observed in ReLEx smile group 1 month (P = 0.029) and 3 months (P = 0.045) postoperatively. No significant differences were found in tear secretion for the two groups (P>0.05). OSDI scores were higher in FS-LASIK group 1 month after surgery (P = 0.020). Higher central corneal sensitivity was observed in ReLEx smile group 1 week, 1 month and 3 months (P<0.05) postoperatively. Compared to FS-LASIK group, lower and faster recovery of IL-6 and NGF levels in tears was observed in ReLEx smile group postoperatively (P<0.05). Tears TNF-α and ICAM-1 concentrations were not significantly different between the two groups at any follow-up time (P>0.05). Moreover, IL-6 and NGF levels correlated with ocular surface changes after ReLEx smile or FS-LASIK.

Conclusions

In the early postoperative period, ReLEx smile results in milder ocular surface changes than FS-LASIK. Furthermore, the tear inflammatory mediators IL-6 and NGF may play a crucial role in the ocular surface healing process following ReLEx smile and FS-LASIK.     

Diabetic Foot Syndrome and Corneal Subbasal Nerve Plexus Changes in Congolese Patients with Type 2 Diabetes

Background

To study the severity of diabetic neuropathy, diabetic retinopathy and grades of diabetic foot syndrome for correlations with corneal subbasal nerve plexus (SBP) changes in Congolese patients with type 2 diabetes.

Methodology/Principal Findings

Twenty-eight type 2 diabetes patients with diabetes-related foot ulceration were recruited in a diabetic care unit in Kinshasa, Democratic Republic of Congo. Corneal SBP was investigated by confocal laser-scanning microscopy to analyse nerve fibre density (NFD) [µm/ µm²], number of branches [n] and number of connectivity points [n]. Foot ulceration was graded using the Wagner ulcer classification. Corneal sensitivity (Cochet-Bonnet), Neuropathy Symptom Score (NSS), Neuropathy Disability Score (NDS), ankle-brachial index (ABI) and ophthalmological status were evaluated. Foot ulceration was ranked as mild (Wagner 0-1: 13 patients/46.4%), moderate (Wagner 2-3: 10 patients/35.7%) and severe (Wagner 4-5: 5 patients/17.9%). The correlation between Wagner Score and NFD (p=0.017, r = - 0,454), NDS and NFD (p=0,039, r = - 0.400) as well as Wagner Score and HbA_1c (p=0,007, r = - 0.477) was stated. Significant differences in confocal SBP parameters were observed between Wagner 0-1 and Wagner 4 5 (number of branches (p=0.012), number of connectivity points (p=0.001), nerve fibre density (p=0.033)) and ABI (p=0.030), and between Wagner 2-3 and Wagner 4-5 (number of branches (p=0.003), number of connectivity points (p=0.005) and nerve fibre density (p=0.014)). Differences in NDS (p=0.001) and corneal sensation (p=0.032) were significant between Wagner 0-1 and Wagner 2-3. Patients with diabetic retinopathy had significantly longer diabetes duration (p=0.03) and higher NDS (p=0.01), but showed no differences in SBP morphology or corneal sensation.

Conclusions/Significance

While confirming the diabetic aetiology of foot ulceration due to medial arterial calcification, this study indicates that the grade of diabetic foot syndrome correlates with corneal SBP changes and corneal sensation in patients in sub-Saharan Africa.     

早期戒烟大鼠肺病理及炎性介质变化

目的观察早期戒烟后大鼠肺组织病理及炎性介质表达变化规律。方法选用Wistar雄性大鼠80只,随机分为对照组及早期戒烟后0天、1周、2周、4周、6周、8周、12周组。采用酶联免疫吸附方法测定各组大鼠血清中IL-8的蛋白质含量,S-P免疫组化学方法检测肺组织NF-κB p65的表达,并光镜下观察HE染色切片、对大鼠气道炎症进行病理学评分。结果早期戒烟组大鼠可见气道上皮细胞纤毛发生粘连、倒伏,上皮细胞空泡变形、坏死、增生,炎症细胞浸润;其血清IL-8浓度、肺组织NF-κB的表达及气道炎症病理评分在戒烟后各时相点较未吸烟对照组明显升高,有统计学意义（P〈0.05）。早期戒烟组大鼠血清IL-8的浓度、肺组织NF-κB的表达及肺组织病理炎症评分在戒烟后略有上升、且在戒烟后8周达到高峰,但随后在戒烟12周时可见IL-8的浓度有下降趋势,肺组织病理炎症反应有所减轻。结论早期戒烟大鼠在戒烟早期虽可见炎症反应略有加重,但随戒烟时间延长,仍可见炎症反应有所减轻。因此,提倡及早且坚持戒烟。     

A Constant-Force Technique to Measure Corneal Biomechanical Changes after Collagen Cross-Linking

Purpose

To introduce a constant-force technique for the analysis of corneal biomechanical changes induced after collagen cross-linking (CXL) that is better adapted to the natural loading in the eye than previous methods.

Methods

For the biomechanical testing, a total of 50 freshly enucleated eyes were obtained and subdivided in groups of 5 eyes each. A Zwicki-Line Testing Machine was used to analyze the strain of 11 mm long and 5 mm wide porcine corneal strips, with and without CXL. Before material testing, the corneal tissues were pre-stressed with 0.02 N until force stabilization. Standard strip extensiometry was performed as control technique. For the constant-force technique, tissue elongation (Δ strain, %) was analyzed for 180 seconds while different constant forces (0.25 N, 0.5 N, 1 N, 5 N) were applied.

Results

Using a constant force of 0.5 N, we observed a significant difference in Δstrain between 0.26±0.01% in controls and 0.12±0.03% in the CXL-treated group (p = 0.003) over baseline. Similarly, using a constant force of 1 N, Δstrain was 0.31±0.03% in controls and 0.19±0.02% after CXL treatment (p = 0.008). No significant differences were observed between CXL-treated groups and controls with 0.25 N or 5 N constant forces. Standard stress-strain extensiometry failed to show significant differences between CXL-treated groups and controls at all percentages of strains tested.

Conclusion

We propose a constant-force technique to measure corneal biomechanics in a more physiologic way. When compared to standard stress-strain extensiometry, the constant-force technique provides less variability and thus reaches significant results with a lower sample number.     

Immune Alterations in Patients with Anti-Interferon-γ Autoantibodies

Autoantibodies against interferon-gamma (IFN-γ) can cause immunodeficiency and are associated with various opportunistic infections. In the present study, we investigated other cellular immune parameters for a better understanding of the immunodeficiency condition in the patients. The numbers of WBC, monocytes and NK cells were increased in patients with anti-IFN-γ autoantibodies (AAbs). Upon TCR activation, T cell proliferation and IL-2 receptor of the patients remained intact. Nonetheless, the Th1 cytokine (IFN-γ and TNF-α) production was up-regulated. The production of Th2 (IL-4) and Th17 (IL-17) cytokines was unchanged. We suggest that, in addition to the presence of anti-IFN-γ autoantibodies, alterations in the cellular immune functions may also contribute to this immunodeficiency.     

Verticality Perceptions Associate with Postural Control and Functionality in Stroke Patients

Deficits of postural control and perceptions of verticality are disabling problems observed in stroke patients that have been recently correlated to each other. However, there is no evidence in the literature confirming this relationship with quantitative posturography analysis. Therefore, the objectives of the present study were to analyze the relationship between Subjective Postural Vertical (SPV) and Haptic Vertical (HV) with posturography and functionality in stroke patients. We included 45 stroke patients. The study protocol was composed by clinical interview, evaluation of SPV and HV in roll and pitch planes and posturography. Posturography was measured in the sitting and standing positions under the conditions: eyes open, stable surface (EOSS); eyes closed, stable surface (ECSS); eyes open, unstable surface (EOUS); and eyes closed, unstable surface (ECUS). The median PV in roll plane was 0.34° (-1.44° to 2.54°) and in pitch plane 0.36° (-2.72° to 2.45°). The median of HV in roll and pitch planes were -0.94° (-5.86° to 3.84°) and 3.56° (-0.68° to 8.36°), respectively. SPV in the roll plane was correlated with all posturagraphy parameters in sitting position in all conditions (r = 0.35 to 0.47; p < 0.006). There were moderate correlations with the verticality perceptions and all the functional scales. Linear regression model showed association between speed and SPV in the roll plane in the condition EOSS (R2 of 0.37; p = 0.005), in the condition ECSS (R2 of 0.13; p = 0.04) and in the condition EOUS (R2 of 0.22; p = 0.03). These results suggest that verticality perception is a relevant component of postural control and should be systematically evaluated, particularly in patients with abnormal postural control.     

Changes of Cytochemical Markers in the Conjunctival and Corneal Epithelium After Corneal Debridement

1. The aim of this study was to determine the epithelial changes of the conjunctiva and cornea up to 7 days after corneal debridement and the changes highlighted included (1) proliferation, (2) production of growth factor, (3) changes in calcium binding protein marker, (4) production of cytokine, and (5) maturity of the regeneration corneal epithelium.2. The cytochemical changes of the corneal and conjunctival epithelia of rabbit were analyzed up to 7 days after debridement.3. An increase in proliferating cell nuclear antigen (PCNA) was observed in the limbal epithelia 12 hr after lesion and reached a peak by 48 hr.4. Some proliferating limbal cells also contained epidermal growth factor (EGF) beginning 24 hr after injury. The early limbal cell proliferation and the EGF production and their persistence until 7 days after lesion were likely involved with the process of regeneration.5. Other positive markers appeared after lesion included tumor necrosis factor (TNF) and calcium binding proteins S100A and S100B, which appeared mainly within the first 48 hr after lesion and then started to decline. The short appearance and the relatively small quantity of TNF indicated that this cytokine was probably not very important in the repair process and its appearance might be related to the injury induced. The presence of S100A and S100B could be associated with both cell death after injury and the proliferation of new epithelium.6. The cornea epithelium was still immature 7 days after lesion in that it still contained cytokeratin.7. In conclusion, the critical hours of peak conjunctival and corneal changes after corneal debridement were in the first 2 days.     

Efficacy of Corneal Collagen Cross-Linking for Treatment of Keratoconus: A Meta-Analysis of Randomized Controlled Trials

ObjectiveTo evaluate the efficacy of corneal collagen cross-linking (CXL) for the treatment of keratoconus.MethodsWe performed a literature search for randomized controlled trials that assessed the effect of CXL in slowing progression of keratoconus. The primary outcome measures included changes of topographic parameters, visual acuity, and refraction. Efficacy estimates were evaluated by weighted mean difference (WMD) and 95% confidence interval (CI) for absolute changes of the interested outcomes.ResultsSignificant decrease in mean keratometry value, maximum keratometry value and minimum keratometry value were demonstrated in the CXL group compared with the control group (WMD = -1.65; 95% CI: -2.51 to -0.80; P < 0.00001; WMD = -2.05; 95% CI: -3.10 to -1.00; P < 0.00001; WMD = -1.94; 95% CI: -2.63 to -1.26; P < 0.00001; respectively). Best spectacle-corrected visual acuity improved significantly in CXL group (WMD = -0.10; 95% CI: -0.15 to -0.05; P < 0.00001), whereas uncorrected visual acuity did not differ statistically. Manifest cylinder error decreased significantly in patients undergoing CXL procedure compared with control patients in sensitivity analysis (WMD = -0.388; 95% CI: -0.757 to -0. 019; P = 0.04). The changes in central corneal thickness and intraocular pressure were not statistically significant.ConclusionCXL may be an effective option in stabilizing keratoconus. Further long-term follow-up studies will be necessary to assess the persistence of CXL.     

Serum Sphingolipid Variations Associate with Hepatic Decompensation and Survival in Patients with Cirrhosis

Background

Sphingolipids constitute bioactive molecules with functional implications in liver homeostasis. Particularly, ablation of very long chain ceramides in a knockout mouse model has been shown to cause a severe hepatopathy.

Methods

We aimed to evaluate the serum sphingolipid profile of 244 patients with cirrhosis prospectively followed for a median period of 228±217 days via mass spectrometry.

Results

We thereby observed a significant decrease of long and very long chain ceramides, particularly of C24ceramide, in patients with increasing severity of cirrhosis (p<0.001). Additionally, hydropic decompensation, defined by clinical presentation of ascites formation, was significantly correlated to low C24ceramide levels (p<0.001) while a significant association to hepatic decompensation and poor overall survival was observed for low serum concentrations of C24ceramide (p<0.001) as well. Multivariate analysis further identified low serum C24ceramide to be independently associated to overall survival (standard beta = -0.001, p = 0.022).

Conclusions

In our current analysis serum levels of very long chain ceramides show a significant reciprocal correlation to disease severity and hepatic decompensation and are independently associated with overall survival in patients with cirrhosis. Serum sphingolipid metabolites and particularly C24ceramide may constitute novel molecular targets of disease severity, hepatic decompensation and overall prognosis in cirrhosis and should be further evaluated in basic research studies.     

Protective Effects of Soluble Collagen during Ultraviolet-A Crosslinking on Enzyme-Mediated Corneal Ectatic Models

Collagen crosslinking is a relatively new treatment for structural disorders of corneal ectasia, such as keratoconus. However, there is a lack of animal models of keratoconus, which has been an obstacle for carefully analyzing the mechanisms of crosslinking and evaluating new therapies. In this study, we treated rabbit eyes with collagenase and chondroitinase enzymes to generate ex vivo corneal ectatic models that simulate the structural disorder of keratoconus. The models were then used to evaluate the protective effect of soluble collagen in the UVA crosslinking system. After enzyme treatment, the eyes were exposed to riboflavin/UVA crosslinking with and without soluble type I collagen. Corneal morphology, collagen ultrastructure, and thermal stability were evaluated before and after crosslinking. Enzyme treatments resulted in corneal curvature changes, collagen ultrastructural damage, decreased swelling resistance and thermal stability, which are similar to what is observed in keratoconus eyes. UVA crosslinking restored swelling resistance and thermal stability, but ultrastructural damage were found in the crosslinked ectatic corneas. Adding soluble collagen during crosslinking provided ultrastructural protection and further enhanced the swelling resistance. Therefore, UVA crosslinking on the ectatic model mimicked typical clinical treatment for keratoconus, suggesting that this model replicates aspects of human keratoconus and could be used for investigating experimental therapies and treatments prior to translation.     

慢性牙周炎患者洁刮治术后牙周微生物变化及意义

目的:研究洁刮治术后慢性牙周炎可疑致病微生物检出量与临床疗效的关系。方法:随机选取我院2012年1月至2014年5月慢性牙周炎患者36例,均采用洁刮治术治疗。分别于治疗前后检测患者牙周膜附着丧失量、牙周探诊深度、出血率以及微生物数量。结果:治疗前后比较,患者牙周探诊深度与探诊出血率差异具有统计学意义(P0.05),临床附着丧失量无统计学差异(P0.05);A组治疗后中间普氏菌数量显著高于治疗前(P0.05);牙龈卟啉单胞菌、齿垢密螺旋体和福赛氏类杆菌显著低于治疗前(P0.05);B组治疗前后细菌数量无统计学差异(P0.05);牙龈卟啉单胞菌C组牙周探诊深度变化显著高于D组(P0.05);齿垢密螺旋体C组探诊出血率变化显著低于D组(P0.05);福赛氏类杆菌C组牙周探诊深度和出血率与D组存在显著性差异(P0.05)。结论:牙龈卟啉单胞菌、齿垢密螺旋体和福赛氏类杆菌数量与洁刮治术后疗效密切相关,可作为微生物指标。     

Effect of Orbital Decompression on Corneal Topography in Patients with Thyroid Ophthalmopathy

Objective

To evaluate changes in corneal astigmatism in patients undergoing orbital decompression surgery.

Methods

This retrospective, non randomized comparative study involved 42 eyes from 21 patients with thyroid ophthalmopathy who underwent orbital decompression surgery between September 2011 and September 2014. The 42 eyes were divided into three groups: control (9 eyes), two-wall decompression (25 eyes), and three-wall decompression (8 eyes). The control group was defined as the contralateral eyes of nine patients who underwent orbital decompression surgery in only one eye. Corneal topography (Orbscan II), Hertel exophthalmometry, and intraocular pressure were measured at 1 month before and 3 months after surgery. Corneal topographic parameters analyzed were total astigmatism (TA), steepest axis (SA), central corneal thickness (CCT), and anterior chamber depth (ACD).

Results

Exophthalmometry values and intraocular pressure decreased significantly after the decompression surgery. The change (absolute value (|x|) of the difference) in astigmatism at the 3 mm zone was significantly different between the decompression group and the controls (p = 0.025). There was also a significant change in the steepest axis at the 3 mm zone between the decompression group and the controls (p = 0.033). An analysis of relevant changes in astigmatism showed that there was a dominant tendency for incyclotorsion of the steepest axis in eyes that underwent decompression surgery. Using Astig PLOT, the mean surgically induced astigmatism (SIA) was 0.21±0.88 D with an axis of 46±22°, suggesting that decompression surgery did change the corneal shape and induced incyclotorsion of the steepest axis.

Conclusions

There was a significant change in corneal astigmatism after orbital decompression surgery and this change was sufficient to affect the optical function of the cornea. Surgeons and patients should be aware of these changes.     

The Post-Resuscitative Urinalysis Associate the Survival of Patients with Non-Traumatic Out-of-Hospital Cardiac Arrest

Objective

To analyze whether urine output and urinalysis results are predictive of survival and neurologic outcomes in patients with non-traumatic out-of-hospital cardiac arrest (OHCA).

Methods

Information was obtained from 1,340 patients with non-traumatic OHCA who had achieved a sustained return of spontaneous circulation (ROSC). Factors that were associated with survival in the post-resuscitative period were evaluated. The association between urine output and fluid challenge in the early resuscitative period was analyzed and compared between the survivors and the non-survivors. The results of the initial urinalysis, including the presence of proteinuria and other findings, were used to evaluate the severity of vascular protein leakage and survival. The association between proteinuria and the neurologic outcomes of the survivors was also analyzed. The clinical features of capillary leakage were examined during the post-resuscitative period.

Results

Of the 1,340 patients, 312 survived. A greater urine output was associated with a higher chance of survival. The initial urine output increased in proportion to the amount of fluid that was administered during early resuscitation in the emergency department for the survivors but not for the non-survivors (p<0.05). In the initial urinalysis, proteinuria was strongly associated with survival, and severe proteinuria indicated significantly poorer neurologic outcomes (p<0.05 for both comparisons). Proteinuria was associated with a risk of developing signs of capillary leakage, including body mass index gain and pitting edema (both p<0.001).

Conclusion

The severity of proteinuria during the early post-resuscitative period was predictive of survival.     

Age-Related Changes in Corneal Deformation Dynamics Utilizing Scheimpflug Imaging

PurposeTo study age-related changes in corneal deformation response to air-puff applanation tonometry.MethodsFifty healthy subjects were recruited for a prospective study and divided into two equal age groups (≤ 28 and ≥ 50 years old). Up to three measurements by a corneal deformation analyser based on the Scheimpflug principle were performed on the left eye of each subject. Raw Scheimpflug images were used to extract changes in anterior and posterior corneal profiles, which were further modelled by an orthogonal series of Chebyshev polynomial functions. Time series of the polynomial coefficients of even order exhibited a dynamic behavior in which three distinct stages were recognized. A bilinear function was used to model the first and the third stage of corneal dynamics. Slope parameters of the bilinear fit were then tested between the two age groups using Wilcoxon rank sum test and two-way non-parametric ANOVA (Friedman) test.ResultsStatistically significant changes (Wilcoxon test, P<0.05) between the age groups were observed in the phase of the second applanation dynamics for the posterior corneal profile. In a two-way comparison, in which the corneal profile was used as a dependent variable, statistically significant changes (ANOVA/Friedman test, P = 0.017) between the groups were also observed for that phase.ConclusionCorneal biomechanics depend on age. The changes in corneal deformation dynamics, which correspond to mostly free return of the cornea to its original shape after the air pulse, indicate that the age related differences in corneal biomechanics are subtle but observable with high speed imaging.