Post-milking application of a Lacticaseibacillus paracasei strain impacts bovine teat microbiota while preserving the mammary gland physiology and immunity

Bovine mastitis (BM) is a major disease in dairy industry. The current approaches - mainly antibiotic treatments - are not entirely effective and may contribute to antimicrobial resistance dissemination, rising the need for alternative treatment. The present study aims to evaluate the impact of post-milking application of Lacticaseibacillus paracasei CIRM BIA 1542 (Lp1542) on the teat skin (TS) of 20 Holstein cows in mid lactation, in order to reinforce the barrier effect of the microbiota naturally present on the teat. Treatment (Lp1542, iodine or no treatment) was applied post-milking twice a day on the 4 teats of healthy animals for 15 days. Blood and milk samples, and TS swabs were collected at day (D)1, D8, D15 and D26 before morning milking and at D15 before evening milking (D15E) to evaluate Lp1542 impact at the microbial, immune and physiological levels. Lp1542 treatment resulted in a higher lactic acid bacteria and total microbial populations on TS and in foremilk (FM) at D15(E) compared with iodine treatment. Metabarcoding analysis revealed changes in the composition of TS and FM microbiota, beyond a higher Lacticaseibacillus abundance. This included a higher abundance of Actinobacteriota, including Bifidobacterium, and a lower abundance of Pseudomonadota on TS of Lp1542 compared with iodine-treated quarters. In addition, Lp1542 treatment did not trigger any major inflammatory response in the mammary gland, except interleukin 8 production and expression which tended to be slightly higher in Lp1542-treated cows compared with the others. Finally, Lp1542 treatment had no impact on the mammary epithelium functionality (milk yield and composition) and integrity (epithelial cell exfoliation into milk and milk Na+/K+ ratio). Altogether, these results indicate that a topical treatment with Lp1542 is safe with regard to mammary gland physiology and immune system, while impacting its microbiota, inviting us to further explore its effectiveness for mastitis prevention.

Comparing Flow Cytometry and ELISpot for Detection of IL-10, IL-6, and TNF Alpha on Human PBMCs

ELISpot and flow cytometry are two methods often utilized side-by-side for detecting secreted and intracellular cytokines, respectively. Each application has its own advantages and challenges. ELISpot is more sensitive compared to ELISA and appears to be more consistent in detecting IL-10 production than flow cytometry. ELISpot can be used for detecting the secretion of multiple cytokines but not from the same cells simultaneously, whereas flow cytometry allows for the concurrent detection of multiple intracellular cytokines by the same cells. Flow cytometry is a convenient technique allowing for the detection of many cytokines at the same time in a population of cells. The restimulation cocktails used for cytokine detection in flow cytometry are hard on cells and lead to decreased cell viability. Using a live dead dye allows for the exclusion of dead cells when analyzing data. We illustrated the differences between ELISpot and flow cytometry by stimulating cells with two toll-like receptor (TLR) agonists, LPS or Pam3CSK4. Both activators increase production of various cytokines, including IL-10, IL-6, and TNF-alpha. The TLR2 antagonist, MMG-11, was used to inhibit this increased cytokine production. We observed some inhibition of IL-6 and IL-10 from Pam3CSK4 stimulation in the presence of MMG-11 by flow cytometry. TNF-α remains largely unchanged as its basal expression is high, but there is some reduction in the presence of MMG-11 for both methods. However, IL-10 was difficult to detect by ELISpot given the low seeding density. Overall, both ELISpot and flow cytometry are good methods for detecting secreted and intracellular cytokines, respectively, and should be used as complimentary assays.

Phenotyping of M1 and M2a Macrophages and Differential Expression of ACE-2 on Monocytes by Flow Cytometry: Impact of Cell Culture Conditions and Sample Processing

Macrophages are ubiquitously distributed throughout the various tissues of the body and perform many functions including the orchestration of inflammatory responses against pathogens by classically activated M1 macrophages and the regulation of wound healing and tissue remodeling by anti-inflammatory, alternatively activated M2 macrophages. The responsibility for these pleiotropic functions lies in the expression of a myriad of surface receptors unique to given subsets of macrophages. Much of what we know about the function of human macrophage subsets has been gleaned by studying in vitro generated macrophages matured in the presence of GM-CSF or M-CSF and polarized with different cytokines. Oftentimes, culture conditions, such as the type of serum used, the duration of the culture, and the use of polarizing cytokines, vary between studies making direct comparisons difficult. Sample preparation and processing (e.g., Ficoll^® enrichment of leukocytes from whole blood) can also influence gene expression on human monocytes. Furthermore, overlap in surface marker expression can make it difficult to distinguish between different macrophage subsets.We directly compared the expression of over 20 different surface markers on M1 and M2a macrophages cultured in either serum-free media or in the presence of fetal bovine serum or human AB serum and found that the presence or type of serum used affected the expression of several markers such as CD200R1 and CD32. Moreover, we compared the expression of these surface markers on polarized and unpolarized macrophages and determined that polarization was critical to the expression of several of these markers including CD38 and SLAM F7. Differences in sample processing can alter the expression of surface markers, such as ACE-2, on monocytes. We observe that ACE-2 expression is higher on human whole blood CD14⁺ monocytes versus Ficoll^®-enriched CD14⁺ monocytes derived from PBMCs (peripheral blood mononuclear cells), where expression can be reduced by up to 50%. These results indicate that differences in serum, culture media, and sample processing can alter gene expression in both human macrophages and monocytes. Importantly, the results of these studies significantly expand our knowledge of the phenotypic differences between human M1 and M2a macrophages and demonstrate the importance of culture conditions in generating these phenotypes.

Observations of a Solar Energetic Particle Event From Inside and Outside the Coma of Comet 67P

We analyze observations of a solar energetic particle (SEP) event at Rosetta's target comet 67P/Churyumov-Gerasimenko during 6-10 March 2015. The comet was 2.15 AU from the Sun, with the Rosetta spacecraft approximately 70 km from the nucleus placing it deep inside the comet's coma and allowing us to study its response. The Eastern flank of an interplanetary coronal mass ejection (ICME) also encountered Rosetta on 6 and 7 March. Rosetta Plasma Consortium data indicate increases in ionization rates, and cometary water group pickup ions exceeding 1 keV. Increased charge exchange reactions between solar wind ions and cometary neutrals also indicate increased upstream neutral populations consistent with enhanced SEP induced surface activity. In addition, the most intense parts of the event coincide with observations interpreted as an infant cometary bow shock, indicating that the SEPs may have enhanced the formation and/or intensified the observations. These solar transient events may also have pushed the cometopause closer to the nucleus. We track and discuss characteristics of the SEP event using remote observations by SOHO, WIND, and GOES at the Sun, in situ measurements at Solar Terrestrial Relations Observatory Ahead, Mars and Rosetta, and ENLIL modeling. Based on its relatively prolonged duration, gradual and anisotropic nature, and broad angular spread in the heliosphere, we determine the main particle acceleration source to be a distant ICME which emerged from the Sun on 6 March 2015 and was detected locally in the Martian ionosphere but was never encountered by 67P directly. The ICME's shock produced SEPs for several days which traveled to the in situ observation sites via magnetic field line connections.

[Mother's experience of planned caesarean section in the absence of the father or companion: Impact of Covid-19 pandemic-related lockdown]

BACKGROUND

The presence of the father or companion during planned caesarean section presents several benefits. However, we found no study regarding the mother's experience of his presence or absence.

MATERIAL AND METHODS

We conducted an observational, prospective, two-centre study based on the data of women who had a planned caesarean section in Bel Air and Mercy Maternities between November 17th 2020 and June 4th 2021. Two groups were formed : a control group, including women who had a c-section in the presence of the father or companion, and a case group, including women who had a c-section without the father or companion due to Covid-19 pandemic-related containment measures. The primary endpoint was to assess the mother's anxiety regarding the presence or absence of the father or companion during planned c-section, by the use of a numerical scale of stress and STAI YA inventory. The secondary endpoint was the appraisal of information given by the medical team concerning c-section and the containment measures.

RESULTS

Regarding the level of stress during the c-section, we did not find a significant difference by the use of the numerical scale of stress. With a mean of 53 in the case group and 49 in the focus group (P=0,048), the STAI YA scores showed a significant difference. Between the day before and the day of the c-section, we found no significant difference by the use of the numerical scale of stress. STAI YA scores showed a significant difference, with a delta of 5 in the case group against 1 in the focus group (P=0,01). Most patients estimated that the information given by the medical team helped to reduce their stress. 93 % of the patients in the focus group reckoned they would have been more stressed in the absence of the father or companion.

DISCUSSION AND CONCLUSION

The significant results of this study suggest the absence of the father or companion during planned caesarean section has an impact on mother's experience. Therefore, this should be considered in order to better our practices and improve mother's experience. In the long term, we could imagine making their presence possible during emergency caesarean sections as well (general anesthesia excluded). We could also envision adding to preparation courses to c-section to birth preparation courses, for mothers (to reduce psychological impact) but also for fathers or companions (to allow their presence in the operation room).

Increased 18F-fluorodeoxyglucose uptake in the cardiac atria: an evidence for increased atrial inflammation in patients with atrial fibrillation?

Funding Acknowledgements

Type of funding sources: None.

Background

Atrial inflammation and fibrotic remodelling underlie the pathophysiology of atrial cardiomyopathy, which is associated with the development of atrial fibrillation (AF) and atrial flutter (AFL). 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) has been used to detect inflammatory processes. Recent studies have revealed an increased FDG-uptake in the atria of patients with AF, but also in patients with diagnosis of cardiac sarcoidosis with ventricular inflammation.

Purpose

This study aimed to assess the capability of PET/CT to detect and quantify the degree of atrial inflammation (FDG-uptake) in a population with dedicated cardiac FDG-PET/CT.

Methods

We investigated 101 patients suspected of sarcoidosis (57±12 years, 72% male) who underwent 18F-FDG PET/CT scan with dedicated cardiac specific preparation (heparin infusion, 12 hours fasting, and high-fat low-carbohydrate diet). We excluded patients with active ventricular cardiac sarcoidosis or undergoing high-dose immunosuppressive therapy (prednisolone ≥20mg/day or prednisolone combined with other immunotherapy like methotrexate). We measured the maximum standardized uptake value (SUVmax) in atrial myocardium and mean standardized uptake value (SUVmean) in blood pool and calculated the target-to-background ratio (TBR) of SUVmax in atrial myocardium to SUVmean in blood pool. All medical records, ECG data on arrhythmia type and diagnosis of systemic sarcoidosis (with absence of ventricular involvement) were used for the analysis. Sarcoidosis was diagnosed based on the criteria established in 2006 by the Japanese Ministry of Health and Welfare. The collected data were sorted according to presence of arrhythmia and systemic sarcoidosis and TBR of each group were compared.

Results

AF or AFL was found in 30/101 patients. Systemic sarcoidosis was found in 37/101 patients. Patients with known AF/AFL had significantly increased TBR within the atrial tissue compared to those without AF/AFL: (median: 1.26, 1st-3rd quartile: 1.20-1.33) versus (median: 1.22, 1st-3rd quartile: 1.14-1.25; p = 0.004; figure A). Arrhythmia-associated atrial inflammation was consistently observed, independently of presence of concomitant systemic sarcoidosis (figure B). Patients with both atrial arrhythmias and systemic sarcoidosis had the highest atrial inflammation level, as identified by TBR (figure B).

Conclusion

Development of atrial fibrillation or flutter is associated with an increased atrial FDG-uptake as metabolic marker of atrial inflammation. The level of atrial inflammation is further enhanced by additional presence of systemic sarcoidosis.

Abstract LB141: Assessment of natural killer (NK) cell activity for immunotherapy using a novel flow cytometry-based killing assay

Natural killer (NK) lymphocytes exhibit potent responses against transformed and pathogen-infected cells. NK cells can act rapidly as they monitor the bloodstream and tissues for tumorigenic and infected cells that lack “self” markers of MHC class I. Upon recognition of a foreign invader or tumor cell, NK cells release cytotoxic proteins such as interferon-gamma and granzyme B. Because of their ability to recognize stressed cells lacking “self” markers, human NK cells have shown promise as therapeutics in clinical trials to reduce disease burden in patients with therapy-resistant or advanced-stage blood cancers. With more than one hundred NK cell- and induced NK cell-based clinical trials ongoing for blood cancers and refractory solid tumors, there is an ever-increasing need for NK cell therapies to treat cancer and immune diseases. We sought to develop novel, clinically relevant, and robust methods for human NK cell expansion. In addition, to simplify the processing of cells for characterization, we developed a flow cytometry based killing assay to monitor NK activity. Therefore, within the same experiment, we can analyze NK cell phenotype profiles with specific antibody panels while also assessing NK cell killing activity. Using optimized serum- and xeno-free conditions with minimal cell manipulations, we have expanded highly purified NK cells up to 500-fold in 14 days from human peripheral blood mononuclear cells (PBMCs) using optimized cytokines and Cloudz CD2/NKp46 microspheres. To characterize the resulting NK cell population, we used a unique antibody panel to phenotype the NK cells by flow cytometry. Within the same experiment, NK killing assays against K562 cells can be performed using a flow cytometry-based killing assay, which has the advantage of using one instrument for all analyses, shortened processing times, and reproducibility. Using this workflow, we can identify different culture conditions that adversely affect NK activity. Together, this data presents a comprehensive and clinically relevant workflow for the expansion of highly purified NK cells and assessing their killing potential. Furthermore, this workflow can be used for screening the activity of chimeric antigen receptor (CAR) expressing immune cells against specific cancer antigens.

Citation Format: Jody Bonnevier, Christine Goetz, Li Peng, Jamie Van Etten, Bora Faulkner, Christopher Hammerbeck, Ariel Miller, Gabriella Perell, Christopher Johnson, Joseph Lomakin, David Hermanson, Kevin Flynn. Assessment of natural killer (NK) cell activity for immunotherapy using a novel flow cytometry-based killing assay [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr LB141.

Risk factors for keratoconus progression after treatment by accelerated cross-linking (A-CXL): A prospective 24-month study

PURPOSE

Identification of potential predictive factors for keratoconus progression after treatment by accelerated Cross-linking (A-CXL) SECONDARY OBJECTIVES: Evaluation of clinical and topographic outcomes for two years following accelerated cross-linking treatment for progressive keratoconus including: best spectacle corrected visual acuity (BSCVA), thinnest pachymetry, maximum keratometry (Kmax), cylinder.

STUDY

Prospective, interventional, monocentric study. SITE: Metz-Thionville Regional Medical Center, Lorraine University, Mercy Hospital, Metz, France.

PATIENTS AND METHODS

We included 82 eyes of 60 patients between March 2014 and June 2016 who underwent accelerated corneal cross-linking (A-CXL) with epithelial debridement for progressive keratoconus, with a minimum follow-up of 2 years. A complete clinical evaluation and corneal topography were performed before cross-linking, and subsequently at 6, 12 and 24 months post-procedure. The following parameters were monitored during follow-up: best spectacle corrected visual acuity (BSCVA), minimal pachymetry, maximum keratometry (Kmax), mean anterior and posterior curvatures, maximum posterior curvature, presence of optical aberrations, subdivided into spherical aberration, coma, astigmatism, higher order optical aberrations and residual optical aberrations. After a 2-year follow-up, two groups, defined as "responders" and "non-responders" to treatment, were separated for analysis, and their initial characteristics were compared.

RESULTS

Data for 82 eyes of 60 patients with progressive keratoconus with a mean age of 24±7 years were studied. Fourteen eyes (17.1%) showed signs of progression after treatment by A-CXL (non-responders), and 68 eyes (82.9%) showed stabilization of the disease (responders). Characteristics of non-responding eyes after A-CXL included a younger mean age (20±5 vs. 25±7 years) (P=0.04) and a lower initial mean BCVA for non-responders of 0.44±0.16 logMAR vs. 0.29±0.19 logMAR (P=0.03). Non-responders also had a higher mean maximal posterior curvature (AKB) of -10.84±1.72D vs. -9.46± 1.12D (P=0.03). They also showed more higher order optical aberrations (3.84±1.72D vs. 2.4±1.02D; P=0.01), including coma (3.85±1.81D vs. 2.1±1.01D; P=0.03) and more residual aberrations than responders (1.05±0.44D vs. 0.45±0.6D; P=0.005). No significant differences were found between responders and non-responders for the other parameters in our study.

CONCLUSION

Eyes with progressive keratoconus who did not respond to A-CXL treatment were the most aggressive cases in the youngest patients, with highest maximum corneal curvatures and most pronounced optical aberrations. These patients should be informed in advance of the high risk of non-response to A-CXL treatment, and of the potential need for additional treatment in the future.

Optimizing DyNaChron instrument for assessing chronic nasal dysfunction symptoms by Rasch analysis

BACKGROUND

The DyNaChron (Dysfonctionnement Nasal Chronique) questionnaire is a self-reporting 78-item instrument assessing six symptoms and their consequences of chronic nasal dysfunction. Patients complete items of a symptom domain only when it is present but in case the patient presents several or all symptoms, its length can limit its use. Here, we aimed to optimize, or shorten, the DyNaChron for clinical use.

METHODS

A total of 640 patients in 14 rhinology outpatient clinics all over France completed the original DyNaChron questionnaire before the first rhinologic clinic and 15 days later. The optimization process involved Rasch analysis and then qualitative content analyses. Rasch analysis flagged items with a floor/ceiling effect or with important differential item functioning and an expert committee decided whether to retain the flagged items on the basis of clinical importance and statistical characteristics. The psychometric properties of the optimized version were studied according to classical test theory and Rasch analysis.

RESULTS

Rasch analysis revealed 4 items with underfit, 6 with an extreme score, 2 that were highly locally dependent and 16 with differential item functioning which 5 of these 16 items were retained after content analysis. In total, 19 flagged items were removed. Factorial analysis confirmed the preservation of the initial instrument structure in the optimized scale; psychometrics properties and scale calibration were the same as or better than the original version.

CONCLUSION

The shortened DyNaChron optimizes the quality of assessment by deleting redundant items and reduces the burden on respondents; the structure is preserved and the psychometrics properties are improved.

Regulation of human macrophage phenotype and GPBAR1 expression by cell seeding density and glucocorticosteroids

Macrophages are key mediators of tissue homeostasis and inflammation and do so by virtue of differential expression of secreted and cell surface proteins. Cytokines such as IFNγ or IL-4 and IL-13 are known to generate classical proinflammatory M1 and alternatively activated M2 macrophages, respectively, but it is less clear how cell density, cell-cell contact and corticosteroids work together to affect macrophage function. Corticosteroids such as cortisol are known to downregulate the inflammatory signaling but they can also alter the expression of cell surface proteins, such as CD163, on steady-state macrophages. Here we examined the effect of monocyte seeding density and cortisol on the expression of cell surface proteins on human macrophages.

The expression of the macrophage markers CD16, CD163, CD204 and VSIG4 were found to correlate with monocyte seeding density such that at low seeding densities, monocyte-derived macrophages were found to express minimal amounts of CD16, CD163, CD204 and VSIG4 while at high seeding densities, expression of these markers was restored. When cultured in the presence of cortisol, macrophages seeded at low densities were found to upregulate expression of these markers, but not CD204, to levels comparable to macrophages seeded at high densities grown in the presence of MCSF. Additionally, in the presence of cortisol, macrophages expressed higher levels of GPBAR1 which has also been shown to reduce classical proinflammatory macrophage activation in colitis models.

This data suggests that corticosteroids may regulate macrophage function by modulating the expression of cell surface proteins such as GPBAR1 and not just interfering with morer conventional inflammatory cell signaling pathways..

Ability of Emergency Department Physicians Using a Functional Autonomy-Assessing Version of the Triage Risk Screening Tool to Detect Frail Older Patients Who Require Mobile Geriatric Team Consultation

OBJECTIVES

Frailty in older people associates with poor outcomes. Screening by ED physicians would greatly facilitate detection of frail older patients but our previous attempt to introduce routine ED-physician screening with Short Emergency Geriatric Assessment (SEGA), a 13-item frailty tool that French geriatricians use to identify frail patients, failed due to its length and complexity. A national committee recently generated a new version of the fast and simple 5-item Triage Risk Screening Tool (TRST) in which a subjective item ('nurse concern') was replaced by an item assessing basic activities of daily living. The ability of ED physicians using this French-TRST to accurately detect frail patients who require comprehensive geriatric assessment was assessed.

DESIGN

Prospective cross-sectional study on diagnostic accuracy relative to the gold standard, namely, geriatrician-administered SEGA.

SETTING

Tertiary-care hospital, France.

SUBJECTS AND MEASUREMENTS

The participants were 498 ≥75-year-old patients who visited the ED in 2018-2019 and were administered French-TRSTs by first ED physicians and then geriatricians, followed by SEGA, all within 24 hours. Diagnostic accuracy variables were calculated. Geriatrician-TRST was used to identify TRST items that associated with ED physician misclassification of frail patients.

RESULTS

Emergency-TRST was significantly less sensitive than Geriatrician-TRST (88% vs. 93%; p=0.04) and tended to have lower negative predictive value (66% vs. 77%; p=0.09). Emergency-TRSTs rated four French-TRST items less well than Geriatrician-TRSTs.

CONCLUSIONS

As a substitute for SEGA in the ED, the French-TRST performed quite well overall but the ED physicians detected frail patients less well than the geriatricians. Modifications of the French-TRST that may improve the diagnostic performance of ED physicians are discussed.

[Determinants of time required by medical information technicians for quality control of hospital activity coding, in French medico-administrative system]

BACKGROUND

Since 2008, in France, hospital funding is determined by the nature of activities provided (activity-based funding). Quality control of hospital activity coding is essential to optimize hospital remuneration. There is a need for reliable tools to allocate human resources wisely in order to improve these controls.

METHODS

The main objective of this study was to identify the determinants of time needed by medical information technicians to control hospital activity coding in a Regional Hospital Center. From March 2016 to the beginning of January 2017, medical information technicians reported the time they spent on each quality control, and the time they needed when they had to code the entire stay. Multiple linear regressions were performed to identify the determinants of quality control or coding duration. A split sample validation was used: model was created on one half of the sample and validated on the remaining half.

RESULTS

Among the controls, 5431 were included in the analysis of determinants of control duration (2715 kept aside for model validation). Seven determinants have been identified (stay duration, level of complexity, month of control, type of control, medical information technician, rank of classing information, and major diagnostic category). The correlation coefficient between predicted and real control duration was 0.71 (P<10^-4); 808 stays were included in the analysis of determinants of coding duration (404 kept aside for model validation). Two determinants have been identified. The correlation coefficient, between predicted and real coding duration, was 0.47 (P<10^-3). We performed the same multiple regression, on 2017 activity data, to estimate the weight of each hospital activity pole, regarding quality control of hospital activity coding.

CONCLUSION

We succeeded in modeling time needed for quality control of hospital stays. These results helped to estimate human resources required for quality control of each hospital pole. Nevertheless, the second analysis did not give satisfactory results: we failed in modeling time needed to code hospital stays.

A De Novo Dominant Negative Mutation in DNM1L Causes Sudden Onset Status Epilepticus with Subsequent Epileptic Encephalopathy

Mitochondrial dynamics such as fission and fusion play a vital role in normal brain development and neuronal activity. DNM1L encodes a dynamin-related protein 1 (Drp1), which is a GTPase essential for proper mitochondrial fission. The clinical phenotype of DNM1L mutations depends on the degree of mitochondrial fission deficiency, ranging from severe encephalopathy and death shortly after birth to initially normal development and then sudden onset of refractory status epilepticus with very poor neurologic outcome. We describe a case of a previously healthy 3-year-old boy with a mild delay in speech development until the acute onset of a refractory status epilepticus with subsequent epileptic encephalopathy and very poor neurologic outcome. The de novo missense mutation in DNM1L (c.1207C > T, p.R403C), which we identified in this case, seems to determine a unique clinical course, strikingly similar to four previously described patients in literature with the identical de novo heterozygous missense mutation in DNM1L.

Supracapsular phacoemulsification: Description of the "Garde à vous" technique and comparative clinical results

Phacoemulsification techniques can be divided into 2 categories: endocapsular and supracapsular techniques. Supracapsular techniques involve phacoemulsification of the nucleus outside and above the capsular plane. The "Garde-à-vous" technique described in this manuscript is a modified and improved version of the supracapsular procedure with up-to-date technology in micro-coaxial surgery. It maintains the known advantages of supracapsular techniques such as faster surgical times and lower rates of capsular tears and brings a standardized technique with well-defined surgical steps in order to achieve tilting of the nucleus in a vertical or oblique position in almost 100% of cases by performing a double-wave hydro-dissection. The authors also give the results of a non-randomized prospective study, comparing the "Garde-à-vous" technique and the standard "cracking" technique in 2856 cases. The results show that for the "Garde-à-vous group", the patients were significantly younger (P<0.001), the power of ultrasound used was greater (P<0.001) for lower UST (ultrasound time or average phacoemulsification time APT) and EPT (effective phacoemulsication time) (P<0.001), the duration of the procedure was shorter (P<0.001), patient discomfort was less (P<0.001), and the power of the implants used was lower (P<0.01). With regard to the gender of the patients, the percentage of topical anesthesia and the rate of intraoperative complications (posterior capsular rupture), there was no statistically significant difference.

Lateral tarsal strip versus lateral tarsal strip with three-snip punctoplasty for managing epiphora in involutional ectropion

PURPOSE

To compare the efficacy of two surgical techniques-lateral tarsal strip (canthoplasty) alone, and lateral tarsal strip with three-snip punctoplasty-in reducing epiphora arising from involutional ectropion with partial punctal stenosis.

METHODS

Fourty patients with involutional ectropion and partial stenosis of the lacrimal punctum were randomly allocated to two treatment groups. Group 1 patients received lateral tarsal strip alone with only non-invasive stenting of the punctum, and group 2 patients received tarsal strip plus three-snip punctoplasty. Subjective assessment of epiphora was achieved via completion of a quality of life (QoL) questionnaire preoperatively and at postoperative month 3. Eyelid position, adverse outcomes and corneal dryness (via Oxford grading scheme) were also assessed postoperatively. Only patients with unilateral problems were included in the study.

RESULTS

Forty eyes of 40 patients were included: 20 in each group. The mean ages of group 1 and group 2 patients were 79±11 and 80±9 years, respectively. All patients reported significantly reduced eye watering after surgery, with no significant intergroup difference in subjective outcomes, except that computer usage and night driving (P<0.05), improved in a more significant way in group 2. Eyelid malposition was corrected in all cases, there were no cases of postoperative punctal eversion, and no significant adverse events or complications occurred. Finally, the mean improvements in the dryness/keratitis score (using the Oxford scheme) were comparable between the 2 groups (P=0.34).

CONCLUSION

The study findings indicate that treatment of involutional ectropion with partial punctal stenosis by lateral tarsal strip with three snip punctoplasty does not provide greater reduction in discomfort secondary to epiphora than conventional lateral tarsal strip alone, except for specific situations such as night driving or computer use.

[Practical assessment of DSAEK in the management of endothelial decompensation following penetrating keratoplasty]

PURPOSE

To report our anatomical and functional results as well as possible complications of the first six Descemet's stripping endothelial keratoplasties (DSAEK) performed in our department for endothelial decompensation after penetrating keratoplasty (PK) METHODS: This was a retrospective and observational monocentric study of six patients with DSAEK after prior PK between January 2015 and July 2016. The data collected were: demographic characteristics (age, sex), ophthalmological comorbidities, initial indication for PK, delay between PK and DSAEK. Best corrected visual acuity (BCVA) preoperatively and at 1, 3 and 6 months postoperatively were collected in Monoyer's and Parinaud scale and converted to log MAR for statistical analysis. The central cornea and graft thickness measured on OCT as well as postoperative complications were also collected.

RESULTS

Mean follow-up duration was 7.2 months [3-10]. The average time after PK was 7.7 years. The mean age of the patients was 67.5 years [32-87]. The initial indication for PK was Fuchs dystrophy (3/6), pseudophakic bullous keratopathy (1/6), corneal laceration (1/6) and other corneal dystrophy (1/6). The authors report one case a combined phaco-DSAEK surgery. The complications observed were: an early graft detachment treated by an additional air bubble injection (1/6) and cystoid macular edema in one other case. The average central corneal thickness decreased from 780μm at day 7 postoperatively to 656μm at 6 months. The average thickness of the graft decreased from 154μm at day 7 to 122μm at 6 months. The mean preoperative BCVA was 1.52 log MAR [1.0-1.7], compared to the mean postoperative BCVA which was 1.5 log MAR [1.1-2.3] at 1 month, 1.15 log MAR [0.5-1.7] at 3 months and 1.1 log MAR [0.7-1.7] at 6 months (data available for 4 patients at 6 months). The recovery of visual acuity was limited in 2 cases, despite corneal clarity restored in all our patients.

DISCUSSION

Our results can be compared to those described in literature. As more penetrating keratoplasty grafts reach the end of their lives, this will allow for more powerful studies.

CONCLUSION

DSAEK on eyes previously treated with PK is a good alternative to a new PK in the case of endothelial decompensation of the graft. The possibility of a posterior lamellar graft allows for faster visual recovery, with preservation of the anterior corneal power and a lower rate of complications.

Central corneal thickness assessment after phacoemulsification: Subluxation versus Divide-and-Conquer

PURPOSE

To compare the impact of two phacoemulsification techniques (subluxation versus divide-and-conquer) on postoperative corneal edema at postoperative hour 1 and day 4.

DESIGN

Comparative study.

METHOD

Ninety-six consecutive patients (110 eyes; 43 men and 53 women, mean age 70.9±9.8 years) with equivalent cataract grades underwent cataract surgery and were followed up for 6 months. The presence of corneal edema was determined using central corneal thickness (CCT). CCT was measured preoperatively, and at postoperative hour 1 and day 4.

MAIN OUTCOME MEASURES

Ultrasound power (US %), duration of ultrasound (TPA), effective ultrasound time (TPE), surgical duration and final suture (%).

RESULTS

Eyes of participants were divided into two phacoemulsification technique groups: subluxation (n=50 eyes) and divide-and-conquer (n=60 eyes). Non-inferiority analysis revealed similar CCT increases at postoperative hour 1 in both groups, with 69.9±44.9μm and 64.4±42.9μm, observed in the subluxation and divide-and-conquer groups, respectively (P=0.033). TPE was similar in both groups, taking 6.2±3.4 and 7.3±4.5seconds in the subluxation and divide-and-conquer groups, respectively (P=0.150). No correlation was seen between TPE and edema at postoperative hour 1, or between TPE and day 4 edema. Rate of final suture use was similar between the subluxation and divide and conquer groups, at 36% and 30%, respectively.

CONCLUSION

The study findings suggest that cataract surgery performed using the subluxation technique does not result in greater CCT than the divide-and-conquer technique. CCT appears to normalize by postoperative day 4, regardless of the technique used.

Phenotypic characterization of fifty surface markers expressed by human M1 and M2a macrophages cultured with different serums and in the presence or absence of polarizing cytokines

Macrophages are ubiquitously distributed throughout the various tissues of the body and perform many functions. These include inflammatory responses against pathogens by classically activated M1 macrophages and the regulation of wound healing and tissue remodeling by anti-inflammatory alternatively activated M2 macrophages. The responsibility for these pleiotropic functions lies in the expression of a myriad of surface receptors unique to a given subset. Much of what we know about the function of human macrophage subsets has been gleaned by studying in vitro generated macrophages, matured in the presence of GM-CSF or M-CSF, and polarized with different cytokines. Oftentimes, culture conditions (such as the type of serum used, the duration of the culture and the use of polarizing cytokines) vary between studies making direct comparisons difficult. Furthermore, overlap in surface marker expression can make it difficult to distinguish between the different macrophage subsets.

We directly compared the expression of fifty different surface markers on M1 and M2a macrophages cultured in the presence of fetal bovine serum, human AB serum or serum free media and found that the type or presence of serum used affected the expression of several markers such as CD200R1 and CD32. Moreover, we compared the expression of these surface markers on polarized and unpolarized macrophages and determined that polarization was critical to the expression of several of these markers, such as CD38 and SLAM F7. The results of these studies should significantly expand our knowledge of the phenotypic differences between human M1 and M2a macrophages as well as demonstrate the importance of culture conditions in generating these phenotypes.

An illustrative review to understand and manage metal-induced artifacts in musculoskeletal MRI: a primer and updates

This article reviews and explains the basic physical principles of metal-induced MRI artifacts, describes simple ways to reduce them, and presents specific reduction solutions. Artifacts include signal loss, pile-up artifacts, geometric distortion, and failure of fat suppression. Their nature and origins are reviewed and explained though schematic representations that ease the understanding. Then, optimization of simple acquisition parameters is detailed. Lastly, dedicated sequences and options specifically developed to reduce metal artifacts (VAT, SEMAC, and MAVRIC) are explained.

Roscovitine has anti-proliferative and pro-apoptotic effects on glioblastoma cell lines: A pilot study

Purine analogue roscovitine, a cyclin-dependent kinase (CDK) inhibitor, has shown strong anti-proliferative and pro-apoptotic effects in solid and hematologic cancers such as non small-cell lung cancer and lymphomas. It targets CDK2, 7 and 9 preferentially, which are also overexpressed in glioblastoma. Τherefore, the biological effects of roscovitine in glioblastoma cell lines were investigated. Glioblastoma A172 and G28 cell lines were incubated with serial concentrations of roscovitine for 24-120 h. Proliferation was measured using the xCELLigence Real-Time Cell Analyzer, an impedance‑based cell viability system. Cell cycle distribution was assessed by flow cytometry and gene expression was quantified by quantitative RT-PCR and western blot analysis. Roscovitine exhibited a clear dose-dependent anti‑proliferative and pro‑apoptotic effect in the A172 cell line, while G28 cells showed a anti-proliferative effect only at 100 µM. The results of the flow cytometric (FACS) analysis revealed a dose-dependent increase of the G2/M and sub-G1 fractions in A172 cells, while G28 cells responded with an elevated sub-G1 fraction only at the highest concentration. Roscovitine led to a dose‑dependent decrease of transcripts of p53, CDK 7 and cyclins A and E and an increase of >4-fold of p21 in A172 cells. In G28 cells, a dose‑dependent induction of CDK2, p21 and cyclin D was observed between 10 and 50 µM roscovitine after 72 h, however, at the highest concentration of 100 µM, all investigated genes were downregulated. Roscovitine exerted clear dose-dependent anti-proliferative and pro-apoptotic effects in A172 cells and less distinct effects on G28 cells. In A172 cells, roscovitine led to G2/M arrest and induced apoptosis, an effect accompanied by induced p21 and a reduced expression of CDK2, 7 and 9 and cyclins A and E. These effects requre further studies on a larger scale to confirm whether roscovitine can be used as a therapeutic agent against glioblastoma.

Optimized surgical treatment for normal pressure hydrocephalus: comparison between gravitational and differential pressure valves

OBJECTIVES

In idiopathic normal pressure hydrocephalus (NPH) ventriculoperitoneal (VP) shunt insertion is the method of choice to improve cardinal symptoms such as gait disturbance, urge incontinence and/or dementia. With reduced compliance, the brain of the elderly is prone for overdrainage complications. This was especially true with the use of differential pressure valve implantation. The present study compares clinical outcome and complication rates after VP shunt insertion with differential pressure valves in the early years and gravitational valves since 2005.

METHODS

The authors reviewed patients treated at our institution for NPH since 1995. Differential pressure valves were solely used in the initial years, while the treatment regimen changed to gravitational valves in 2005. Clinical improvement/surgical success rates as well as complications were compared between the two groups.

RESULTS

Eighty-nine patients were enrolled for the present study. Mean age at the time of surgery was 73.5 ± 6.3 years. Male patients predominated with 73, compared with 16 female patients. Median follow-up time was 28 ± 26 months. Date of last follow-up was 1st October 2013. Forty-nine patients received a gravitational valve, while 40 were treated with differential pressure valves. In the gravitational group a significant improvement was observed after shunt insertion for gait disorder, cognitive impairment and urge incontinence (p < 0.0001, resp. p = 0.004), while a significant change in the differential pressure group was only seen for gait disorder (p = 0.03) but not for cognition or urinary incontinency (p > 0.05). The risk of hygroma as a sign of shunt overdrainage requiring surgical intervention was significantly higher in the differential pressure group (5 versus 0 in the gravitational group).

CONCLUSIONS

Patients with NPH treated with gravitational valves in the present cohort showed a more profound improvement in their initial symptoms, including gait disorder, cognitive impairment and urinary incontinency without the risk of overdrainage complications requiring surgical intervention when compared with patients who received differential pressure valves in previous years.

Comparative Multi-Donor Study of IFNγ Secretion and Expression by Human PBMCs Using ELISPOT Side-by-Side with ELISA and Flow Cytometry Assays

ELISPOT, ELISA and flow cytometry techniques are often used to study the function of immune system cells. It is tempting to speculate that these assays can be used interchangeably, providing similar information about the cytokine secreting activity of cells: the higher the number of cytokine-positive cells measured by flow cytometry, the higher the number of cytokine-secreting cells expected to be detected by ELISPOT and the larger the amount of secreted cytokine expected to be measured by ELISA. We have analyzed the expression level and secretion capacity of IFNγ from peripheral blood mononuclear cells isolated from five healthy donors and stimulated by calcium ionomycin mixed with phorbol 12-myristate 13-acetate in a non-specific manner in side-by-side testing using ELISPOT, ELISA and flow cytometry assays. In our study, we observed a general correlation in donors' ranking between ELISPOT and flow cytometry; ELISA values did not correlate with either ELISPOT or flow cytometry. However, a detailed donor-to-donor comparison between ELISPOT and flow cytometry revealed significant discrepancies: donors who have similar numbers of IFNγ-positive cells measured by flow cytometry show 2-3-fold differences in the number of spot-forming cells (SFCs) measured by ELISPOT; and donors who have the same number of SFCs measured by ELISPOT show 30% differences in the number of IFNγ-positive cells measured by flow cytometry. Significant discrepancies between donors were also found when comparing ELISA and ELISPOT techniques: donors who secreted the same amount of IFNγ measured by ELISA show six-fold differences in the number of SFCs measured by ELISPOT; and donors who have 5-7-times less secreted IFNγ measured by ELISA show a two-fold increase in the number of SFCs measured by ELISPOT compared to donors who show a more profound secretion of IFNγ measured by ELISA. The results of our study suggest that there can be a lack of correlation between IFNγ values measured by ELISPOT, ELISA and flow cytometry. The higher number of cytokine-positive cells determined by flow cytometry is not necessarily indicative of a higher number of cytokine-secreting cells when they are analyzed by either ELISPOT or ELISA. Our ELISPOT vs. ELISA comparison demonstrates that the higher number of SFCs observed in ELISPOT does not guarantee that these cells secrete larger amounts of cytokines compared to donors with lower SFC numbers. In addition, our data indicate that ELISPOT, ELISA and flow cytometry should be performed as complementary, rather than stand-alone assays: running these assays in parallel on samples from the same donors may help to better understand the mechanisms underlying the physiology of cytokine-secreting cells.

Convergence of NF-κB-mediated inflammatory and HNF4α-mediated metabolic signaling networks in age-related thymic involution (HEM4P.229)

Thymic epithelial cell loss results in age-related thymic involution and immune deficiency. We investigated mechanisms of TEC loss during chronological aging (6 weeks, 7 months, 15 months) of normal C57BL6/J mice. Aged TEC showed replicative senescence with increased apoptosis, decreased proliferation, decreased telomerase activity and shortened telomere length. A subpopulation of aged TEC expressed Fas in response to pro-inflammatory cytokines (TNFα,IL-1β) made by aged thymocytes. Fas signaling and caspase-8 activation were induced by FasL selectively expressed by aged intrathymic memory T cells. Combined pharmacological inhibition of Caspase-8 and TEC growth stimulation by KGF restored thymopoiesis to neonatal levels. Aged TEC differentially expressed a 175-gene set predicted to be dually regulated by two transcription factors, NF-κB and HNF4α, which are activated by inflammatory cytokines and fatty acids, respectively. NF-κB and HNF4α signaling in aged TEC was confirmed by ChIP assays demonstrating binding to promoters of age-related genes, gene reporter assays, and synergistic induction of TEC apoptosis by inflammatory cytokines and fatty acids. TEC aging is mediated by the convergence of different TFs responsive to inflammatory and metabolic signals on shared promoters. Thymic regeneration in aging will require mitigation of the effects of non-autonomous inflammatory and metabolic signals, e.g., from infection and obesity, which drive TEC death and thymic involution.

Thymic aging in the absence of klotho (HEM4P.243)

Age-related thymic involution, characterized by a decrease in thymic epithelial cell (TEC) proliferation, absolute number, and organization, results in overall defective support of T cell development and proliferation and is a major cause of thymic dysfunction. Using a genetic model of advanced aging caused by deficiency of Klotho, an anti-aging gene and modifier of FGF signaling, we investigated TEC-intrinsic aging in the absence of a globally aging environment. By one month of age, Klotho deficient (Kl-/-) mice display a disrupted thymic architecture, a 4-6 fold decrease in TEC numbers, as well as significant decreases in all thymocyte populations and also a 3-8 fold decrease in peripheral T cell numbers. To separate thymus-intrinsic aging from the effects of organismal aging, we implanted fetal thymi from Kl-/- mice under the kidney capsule of mice lacking thymi. Kl-/- and WT fetal thymi supported comparable levels of thymopoiesis as measured by the numbers of T cells in peripheral blood and lymphoid organs up to 4 months post-implantation, with both cohorts of implants not detectable past 5 months. In this aging model, isolation from the systemic effects of Klotho deficiency attenuates age-related thymic dysfunction, suggesting that extrathymic factors affect thymic aging.

Development of a new mouse/human FoxP3 antibody using rabbit recombinant antibody technology (IRC4P.477)

Tregs play a key role in immune system suppression during autoimmunity and tumor development. Tregs are classified as CD4+CD25+FoxP3+, and exist as either nTregs originating from the thymus, or iTregs derived from CD4+ effector T cells in the periphery. Reduction in Treg numbers leads to autoimmunity; this is clearly shown in scurfy mice where FoxP3 has been deleted, Treg numbers are severely reduced, and mice succumb to autoimmunity early in life. In contrast, Tregs play a debilitating role in cancer biology when the Treg numbers are elevated, and the immune response is dampened allowing cancer cells to evade the immune system. Thus, the correct balance of Tregs is essential for maintaining immune homeostasis. FoxP3 has been widely used as a marker of Tregs, and many antibodies are available on the market that distinguish the Treg population in human or mouse cells. We developed a novel FoxP3 antibody and Fix and Perm buffer system that is comparable to current clones, but recognizes both mouse and human FoxP3 equally well, eliminating the need for separate antibodies. The ms/hu FoxP3 antibody was generated using our Rabbit Recombinant antibody technology, which allows for selecting high specificity, high affinity antibodies, lot to lot consistency and detection of both mouse and human nTregs and iTregs. This allows researchers to extend their mouse models into clinical studies without a change in the antibody clone eliminating a variable and streamlining the process.

Profiling secreted cytokines from human Th2 and Th17 cells using antibody arrays (TECH1P.845)

Naive T Helper cells can differentiate into Th1, Th2, and Th17 lineages which each secrete a characteristic signature of molecules. In this study, we demonstrate the utility of antibody arrays to monitor T cell differentiation processes. Naive T cells were isolated from PBMC preparations obtained from different donors. Following activation, the generation of each T cell subtype was confirmed by flow cytometry. Secreted proteins present in the cell culture supernatants were analyzed with a Human XL Cytokine Array containing 102 analytes. More than 30 proteins were identified, including cytokines specific to each Th subtype. ELISA data were used to quantitatively confirm the increases and decreases of multiple Th-specific cytokine levels observed using the array. These data demonstrate that antibody arrays provide an efficient tool to simultaneously study multiple parameters in complex biological processes where alternate differentiation protocols are being tested along with evaluating the impact of donor-to-donor variability.

Identification of novel cell surface markers on mouse and human TH17 cells (P6354)

TH17 cells are a subset of CD4+ T helper cells that protect against extracellular bacteria, but may also be involved in autoimmune disease progression. Consequently, basic and clinical research on TH17 cells has become a prominent and active area of research in immunology. The TH17 subset is defined by the ability to produce cytokines, such as IL-17 and IL-22, and also by the expression of cell surface markers, such as the IL-23 receptor. Much research effort in TH17 cell biology is the search for surface molecules that can be used to consistently characterize TH17 cells in different immune environments, and ultimately lead to potential therapies for autoimmunity. To date, only a few surface molecules have been found that are exclusively expressed by TH17 cells, making the use of surface markers for this cell type a challenge. Our objective was to identify new surface markers to distinguish TH17 cells from other subsets of helper CD4+ T cells. In order to accomplish this goal, we used a high-throughput flow cytometer to screen over 700 surface antibodies on mouse and human TH17 cells. We identified 26 novel surface markers in human TH17 cells that also coexpress IL-22, IL-17, and RORgT, confirming these markers were on functional TH17 cells. Interestingly, 4 of these markers (BTLA, CD200, CD99, and IL-18Ra) were also identified in mouse TH17 cells. Further study of these markers will enable the development of therapies for autoimmunity and cancer research.

Interstitial iodine-125 radiosurgery alone or in combination with microsurgery for pediatric patients with eloquently located low-grade glioma: a pilot study

PURPOSE

The optimal therapeutic management of children with World Health Organization grade I and II gliomas not accessible to complete resection is poorly defined. Radical surgical resection is the first-line treatment for large hemispheric tumors, whereas interstitial iodine-125 radiosurgery (IRS) might be an attractive treatment concept for selected patients with small (tumor diameter in the range of 4 cm) and circumscribed tumors in any location of the brain. Precise high-dose application, maximal sparing of surrounding normal tissue, and the absence of long-term complications have been reported to be the hallmark of IRS. Therefore, the therapeutic impact and the risk of IRS alone or in combination with microsurgery (in case of larger tumor volumes) were prospectively examined.

METHODS

Seven boys and four girls were included (mean age, 6.8 years; range, 11 months to 16 years). IRS (after stereotactic biopsy) was considered to be indicated for circumscribed tumors with a diameter in the range of 4 cm (four cases). For larger tumors, a combined microsurgical/radiosurgical approach was preferred (seven patients). Temporary iodine-125 seeds were used exclusively (tumor dose calculated to the boundary, 54 Gy; dose rate, 10 cGy/h). Tumor location was hypothalamic/suprasellar in four, lobar in three, deep (thalamus and pineal gland) in two, and within the brain stem in two children. Treatment effects of IRS were estimated according to the MacDonald criteria.

RESULTS

A complete response after IRS was seen in four patients, and a partial response was seen in seven patients (median follow-up, 31.5 months). There was no perioperative morbidity after microsurgery and/or IRS, and no radiogenic complications occurred during the follow-up period. Five patients experienced an improvement in their deficits, and no deterioration in neurological/endocrine function was seen in any of the patients at the time of last follow-up evaluation.

CONCLUSION

IRS alone or in combination with microsurgery (in the case of larger tumors) is a safe, effective, and minimally invasive treatment strategy for eloquently located pediatric low-grade gliomas and deserves further prospective evaluation.

Rasagiline-associated motor improvement in PD occurs without worsening of cognitive and behavioral symptoms

BACKGROUND

Cognitive and behavioral adverse events (AEs) such as hallucinations, confusion, depression, somnolence and other sleep disorders commonly limit effective management of motor symptoms in PD. Rasagiline (N-propargyl-1(R)-aminoindan) mesylate is a novel, second-generation, selective, irreversible monoamine oxidase type B inhibitor, demonstrated in monotherapy and adjunctive trials to be effective for PD with excellent tolerability.

METHODS

The occurrence of cognitive and behavioral AEs and the change from baseline in the Unified Parkinson's Disease Rating Scale (UPDRS) part I mental subscores were reviewed in two multicenter, randomized, placebo-controlled, 26-week trials of rasagiline for early and moderate-to-advanced patients with PD. The UPDRS is a multi-item rating scale specific to PD; part I rates the patient's intellectual impairment, thought disorders, depression and motivation/initiative.

RESULTS

The TEMPO study evaluated rasagiline monotherapy in early PD patients (n=404). The PRESTO study evaluated rasagiline as adjunctive therapy in moderate-to-advanced PD patients with motor complications who were receiving optimized levodopa/carbidopa (n=472). In the analysis of adverse event reporting for both studies, no cognitive and behavioral AE in either the rasagiline 1 mg or placebo groups exceeded 10% of the study population and the frequency differences between rasagiline 1 mg and placebo never exceeded 3%. There was no adverse effect on the UPDRS mental subscore relative to placebo in either of the two studies.

CONCLUSION

Rasagiline 1 mg once daily improves PD symptoms and motor fluctuations in early and moderate-to-advanced PD patients without causing significant cognitive and behavioral AE or adverse changes in mentation, behavior and mood.

Thermography - a valuable tool to test hydrocephalus shunt patency

INTRODUCTION

Shunt-function in hydrocephalic patients is verified by clinical examination and repeated cranial computed tomography (CCT) in most cases. Because of the disadvantages of multiple radiation especially in children it was our aim to introduce video-thermography as a simple and non-invasive methodology to evaluate shunt function.

METHODS

54 patients treated with shunts for hydrocephalus were tested. A ventriculo-peritoneal shunt had been implanted in 38 patients, a ventriculo-atrial shunt in 16 patients. Recent CCT-scans were available for all patients and served as control. None of the patients presented with clinical signs of shunt-dysfunction. The temperature of the skin covering the drainage catheter distal to the valve was recorded real-time by a calibrated infrared camera. After cooling the skin area downstream of the valve for exactly 1 min with an ice pack, changes of the skin temperature in the area downstream were registered by a thermocamera. The signals were transferred to a video screen and recorded on videotape. By off-line analysis of the obtained pseudo colour images variations of 0.1 degrees C in skin temperature could be measured.

RESULTS

Temperature distribution of the area under investigation revealed a significant reduction of the skin temperature according to the location of the downstream catheter segment in 48 patients after cooling. In 6 patients skin temperature remained constant, although clinical evaluation and CCT-scan showed no signs of shunt dysfunction. Shunt patency could be verified in more than 85% of the patients by thermal imaging.

CONCLUSION

Infrared-thermography is a valuable and promising tool for replacing CCT-scanning as a screening method to test shunt function in hydrocephalic patients.