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Biomedical subjects

C Chiquet

Publications and source records attributed to C Chiquet.

At least 19 recordsLinked to original sources

Non-arteritic anterior ischaemic optic neuropathy is nearly systematically associated with obstructive sleep apnoea.

AIM: To evaluate newly diagnosed non-arteritic anterior ischaemic optic neuropathy (NAION) patients for the existence of an associated sleep apnoea syndrome. METHODS: Newly identified NAION patient underwent polysomnography. The prevalence of sleep apnoea in NAION patients was compared to the prevalence previously found in the general population. Hypertension, diabetes, hyperlipidaemia, and atheromatous lesions of carotid vessels as classic risk factors associated with NAION were also identified. RESULTS: 27 consecutive newly diagnosed NAION patients (18 men and nine women, mean age 65 (SD 8) years, body mass index 27.2 (3.8) kg/m2) were included in the study. 24 of these 27 NAION patients (89%) exhibited a sleep apnoea syndrome (respiratory disturbance index: 37.2/h (SD 18.3/h). Risk ratio for a NAION patient to have sleep apnoea was 4.9 compared to the general population (p < 0.001). Sleep apnoea was 1.5-2-fold more frequent than the rate of the other identified risk factors typically associated with NAION (hypertension, diabetes). CONCLUSIONS: Sleep apnoea is the most frequent disorder associated with NAION and should be screened in this population. At least a questionnaire related to obstructive sleep apnoea symptoms and assessment of sleepiness should be systematically proposed to patients with NAION.

Adult↗

[Consequences of glaucoma on circadian and central visual systems].

Glaucoma is a chronic optic neuropathy leading to a degeneration of retinal ganglion cells. There is accumulating evidence that glaucomatous damage extends from retinal ganglion cells to vision centers in the brain. Degenerative changes are observed in magnocellular, parvocellular, and koniocellular pathways in the lateral geniculate nucleus, and these changes are related to intraocular pressure and the severity of optic nerve damage. In addition, recent studies show that there are also changes in the visual cortex in relation to varying degrees of retinal ganglion cell loss. In a rat model of glaucoma, we have recently demonstrated a reduction of retinal projections of retinal ganglion cells, not only on the visual system but also on the suprachiasmatic nucleus. Human studies suggest that the ganglion cell degeneration caused by glaucoma could lead to a lesion of the retinohypothalamic tract, which permits the synchronization of circadian rhythms.

Brain Diseases↗

[How to ensure that glaucoma is stable? Intraocular pressure].

In patients with open-angle glaucoma, intraocular pressure (IOP) obtained through treatment should guard against the progression of glaucoma damage. This depends on the initial state of intraocular pressure, but also on the stage of glaucoma, how fast the alterations are progressing, the patient's age and life expectancy, as well as the presence of other risk factors. To determine the ideal level of treated IOP, the term "target pressure" is often used. This term is very much open to criticism, however, because it calls on a static figure for what is highly variable biological information belonging to the body's biological rhythms. A large number of formulas are used to calculate this target pressure number, but all of them come up against the disadvantage of not taking into account the variations in IOP during the day/night cycle. Yet it is these very variations that can characterize the severity of the disease in terms of IOP. In a glaucoma patient, the IOP curve plotted over 24 h has higher IOP values during the day than at night, contrary to a healthy subject. Fluctuations of more than 10 mmHg are not rare during the day/night cycle, most often with many peaks, which are deleterious for retinal nerve fibers. These dynamic pressure parameters are essential both in determining the therapeutic strategy and in evaluating the effectiveness of treatment. In practice, with any case of open-angle glaucoma and before any treatment is given, a diurnal curve should be established. Six to eight measurements between 8 AM and 6 or 8 PM should be enough. They should be carefully combined with concomitant measures of systemic blood pressure. Once treatment has started, we suggest that a new diurnal curve be established 1 month and then 4 months after the beginning of treatment. The treatment will be modified if needed, based on IOP criteria established at 1 month, and on IOP, perimetric, and anatomic criteria determined again at 4 months. If the disease continues to worsen despite a satisfactory diurnal IOP, IOP should be measured over 24 h, associated with Holter monitoring, looking for an escape of pressure at night.

Circadian Rhythm↗

[Conjunctival tumors in children. A histopathologic study of 42 cases].

PURPOSE: The aim of this study was to describe the clinicopathological characteristics of 42 conjunctival tumors surgically removed in children. PATIENTS AND METHODS: Records of all conjunctival tumors surgically removed in children during the 11-year period 1990-2001 were collected from the records of the Department of Ophthalmology, Edouard Herriot Hospital, Lyon. In all cases, the tumor was resected with no additional treatment. Sections of all cases were reviewed by the same pathologist. RESULTS: A total of 42 cases (40 patients) were included in the study. The mean age of the subjects at the time of surgical excision was 10 years, with a range of 1-17 years; 45% were male. The most frequent indication for tumor removal was suspected growth. The clinical diagnosis was accurate in 91% of cases. The tumor was localized at the limbus in 57% of cases. Most tumors were pigmented nevi, accounting for 83% of the lesions. The histopathological diagnoses in decreasing order of frequency were: nevi (35), angioma (2), dermolipoma (2), dermoid (1), papilloma (1), and squamous cell carcinoma (1). In one case, the histological study revealed squamous cell carcinoma in a child suffering from xeroderma pigmentosum. CONCLUSIONS: This retrospective study suggests that malignancy of pigmented conjunctival lesions is extremely rare in children. Although squamous cell carcinoma is rare in children, surgical excision and histological study are necessary when a conjunctival lesion is associated with xeroderma pigmentosum or immunodeficiency.

Adolescent↗

[Opacification of a hydrophilic acrylic intraocular lens].

PURPOSE: To report pathological and histochemical analysis of an explanted opacified hydrophilic acrylic intraocular lens. PATIENTS: and method: A hydrophilic acrylic intraocular lens--Orion IFP3D6--was explanted 2 years after routine phacoemulsification because of its opacification associated with significant visual impairment (20/40). The intraocular lens was examined by gross and light microscopy. Full-thickness cut sections of the lens were stained with 1% alizarin red (a special stain for calcium). RESULTS: Microscopic analyses revealed the presence of granules of various sizes distributed in a line parallel to the anterior and posterior curvatures of the lens. The granules stained positively for alizarin red. CONCLUSION: Such opacification has been described with the SC60B-OUV, MDR Inc., which is also a one-piece foldable-design intraocular lens (28% hydrophilic material). The opacification of the intraocular lens occurred over various periods after surgery. Forty percent of these lenses have been explanted. Microscopic and histochemical evaluation of these intraocular lenses revealed the same type of granulation deposits within the lenses. The origin and mechanism of the opacification are still not fully understood.

Female↗

Melatonin secretion is supersensitive to light in migraine.

The present study examined the sensitivity to light of melatonin (MLT) secretion in familial migraine during a headache-free interval. Twelve female patients and 12 healthy controls were included in the trial. All subjects were studied twice. In each session, light exposure (300 lx) or placebo was randomly administered for 30 min between 00.30 and 01.00 h. Blood was sampled hourly between 20.00 and 24.00 h, and 02.00 and 04.00 h and every 15 min between 00.30 and 01.30 h. Plasma MLT levels were determined by radioimmunoassay. MLT suppression was more marked in the migraine group than in the control group [difference of area under curve (DeltaAUC)=-53.8 +/- 16.2 vs. 18.5 +/- 12.7 pg/h/ml, P<0.005; maximum of MLT suppression (Delta)=-35.7 +/- 10.2 vs. - 6.7 +/- 5.8 pg/ml, P<0.05]. These findings show a clear hypersensitivity to light in young female migraineurs during the headache-free period.

Circadian Rhythm↗

[The neuroanatomical and physiological bases of variations in intraocular pressure].

Intraocular pressure displays a distinct circadian rhythm in animals and humans, with an increase at night and a decrease during the daytime. In animals, the IOP rhythm has been reported to be synchronized by environmental light and to persist in constant darkness, demonstrating a circadian component controlled by an endogenous pacemaker. The structures involved in the rhythmic regulation of intraocular pressure include the suprachiasmatic nucleus, which controls the activity of sympathetic and parasympathetic ocular innervation. These effectors are responsible for controlling the production (beta-adrenergic system) and the outflow (alpha1-adrenergic, parasympathetic system, prostaglandin) of aqueous humor. The production of aqueous humor is under adrenergic control (alpha1- and beta-receptors). Many neuropeptides such as vasoactive intestinal peptide, substance P, and the atrial natriuretic peptide are also involved in the regulation of intraocular pressure. A better understanding of the circadian regulation of intraocular pressure is needed for an appropriate treatment of ocular hypertension and glaucoma.

Afferent Pathways↗

Mechanisms of staurosporine induced apoptosis in a human corneal endothelial cell line.

BACKGROUND: Apoptosis very probably plays a key part in endothelial cell loss during corneal storage in organ culture as well as hypothermic storage. However, the mechanisms underlying endothelial apoptosis are poorly understood. The response of a human corneal endothelial cell (HCEC) line to staurosporine, a known inducer of apoptosis, was investigated to gain insights into the intracellular modulators that participate in endothelial cell death. METHODS: Immortalised HCECs were studied after 3, 6, 12, and 24 hours of incubation with 0.2 micro M staurosporine. Cell shedding was monitored. Hoechst 33342 fluorescent DNA staining combined with propidium iodide was used for apoptosis/necrosis quantification and morphological examination. The caspase-3 active form was assessed using western blot, proteolytic activity detection, and immunocytochemistry. The cleaved form of poly(ADP-ribose) polymerase (PARP) was assessed using immunocytochemistry and western blot. The ultrastructural features of cells were screened after 12 hours with staurosporine or vehicle. RESULTS: The specific apoptotic nature of staurosporine induced HCEC death was confirmed. The ultrastructural features of staurosporine treated cells were typical of apoptosis. HCEC shedding and DNA condensation increased with time. Caspase-3 activity was detected as early as 3 hours after exposure with staurosporine, peaking at 12 hours of incubation. The presence of cleaved PARP after 3 hours confirmed caspase-3 activation. CONCLUSIONS: These data suggest strongly that HCEC cell death induced by staurosporine is apoptosis. The main consequence of HCEC apoptosis is shedding. Staurosporine induced apoptosis of endothelial cells involves activation of caspase-3, and could be a useful model to study strategies of cell death inhibition.

Apoptosis↗

[Facial anesthetic blocks in the treatment of acute pain during ophthalmic zoster].

BACKGROUND: Ophthalmic zoster is frequently accompanied by severe pain in the frontal and nasal divisions of the ophthalmic nerve. Treating this pain is often difficult, particularly in elderly patients, owing to iatrogenic effects and to interactions with the pre-existing diseases and treatments frequently present in this age group. The aim of our study was to consider the efficacy and toxicity of the frontal and nasal nerve blocks in the treatment of severe pain during acute ophthalmic zoster in the elderly. MATERIAL AND METHODS: A prospective study was conducted on 20 patients (mean age, 76 +/-7 years; range, 63-88) presenting with acute ophthalmic zoster with severe pain (less than 1 month since onset), which had resisted analgesic medication. All patients had a visual analogue score for pain (VAS) of 4 or more and received one or more anesthetic blocks of a compound of bupivacaine with adrenaline associated with clonidine at the frontal branch and sometimes the nasal branch levels of the ophthalmic nerve. Pain was measured daily by VAS for 5 days, and the blocks were repeated if the VAS was still 4 or higher. Patients were checked for local or systemic side effects. RESULTS: The number of anesthetic blocks per patient ranged from one to four (mean: 2.3 +/-0.7). All patients experienced less pain after the first injection. The mean preinjection VAS was 7.4 +/-1 and fell to 4.8 +/-1.0, 4.1 +/-1.1, 3.5 +/-1.0, 3.2 +/-0.6 and 2.8 +/-0.9 at day 1, day 2, day 3, day 4 and day 5, respectively (p<0.001). It was possible to reduce analgesic medication permanently in all patients. No local or systemic side effect was observed. CONCLUSION: Anesthetic blocks of the frontal and nasal branches, repeated if necessary, give fast and effective relief from the severe pain of acute ophthalmic zoster. They are fully tolerated and simple to administer, making them an excellent indication in the complementary treatment of the pain of hyperalgic acute zoster in the elderly.

Acute Disease↗

[Optimizing microbiological controls of corneal organ culture media].

BACKGROUND/AIMS: To compare the efficiency of an automated method using blood bottles with conventional microbiological tests for controlling sterility in cornea organ culture media. METHODS: Two complementary studies were conducted. Experimental study: standard organ culture media were contaminated with four different inocula of 14 bacteria and 3 fungi. The bactericidal activity of organ culture media were evaluated after 48 hours of incubation at 31C. Observational study: 357 samples of organ culture media were collected over 1 year in our cornea bank. For both studies, media were inoculated in three blood bottles (aerobic, anaerobic, fungal) placed in an automat with automated detection every 10 minutes, and in three conventional microbiological media as a control. Changes in organ culture medium color and growth on conventional broth were checked daily by visual inspection. All samples were observed experimentally for 14 days. The sensitivity and rapidity of contamination detection were compared across the three methods: blood bottles, conventional method, and visual inspection of medium color. RESULTS: Experimental study: organ culture medium eradicated five bacteria: S. pneumoniae, B. catarrhalis, E. coli, P. acnes and H. influenzae. For the others, (Methicillin-resistant S. aureus, Methicillin-sensitive S. aureus, S. epidermidis, S. haemolyticus, P. aeruginosa, A. baumannii, B. subtilis, K. pneumoniae, E. faecalis, C. albicans, C. kruzei, A. fumigatus) the blood bottle method, the conventional microbiological method, and the visual inspection detected microbiological growth respectively in 100%, 76.5%, and 70% of cases. Mean detection time using blood bottles was 15.1 hours (standard deviation, 13.8; range, 2-52). In cases of detection by the blood-bottle method and the conventional method, the former was always faster: 95.5% versus 65.2% detection within 24 hours (p=0.022). Observational study: the global contamination rate was 8% (29/357 analysis). The gain in sensitivity with blood bottles was 25% compared with the conventional method. Five bacteria (three coag. neg Staphylococcus, one E. faecalis, one P. paucimobilis) were detected only by the blood bottles. In addition, these were always detected more quickly with, respectively, 66.6% versus 26.6% detection with 24 hours (p=0.028). CONCLUSIONS: Blood bottles detect contaminations of cornea organ culture media more efficiently and faster than conventional microbiological methods. They make it possible to reduce the quarantine period with an equally high security level. Consequently, they should be recommended in cornea preservation guidelines.

Bacteria↗

Characterization of calbindin-positive cones in primates.

The aim of this study is to characterize calbindin-positive photoreceptors and their opsin content in the retina of nocturnal prosimians (Microcebus murinus), New World monkeys (Callithrix jacchus), Old World monkeys (Macaca fascicularis), and humans. To identify the calbindin and opsin content of cones, combined multiple labeling with different fluorescent probes, antibodies directed against calbindin, short, and mid-long wavelength opsins, and lectin peanut agglutinin cytochemistry were used. With the exception of Microcebus, calbindin is present in the cones of all primates but is absent from rods. The distribution of calbindin is similar in human and macaque cones, with dense label in the inner segment, cell body, axon and cone pedicle. Cones in marmoset also show dense staining in the cell body, axon and pedicle but only light label in the inner segment. Primate cone outer segments do not contain calbindin. In the primates studied, three patterns of calbindin and opsin localization are observed. In macaque and marmoset all short and mid-long wavelength cones contain calbindin. In humans, all mid-long wavelength cones contain calbindin whereas all short wavelength cones are devoid of calbindin as confirmed by confocal microscopy. In the nocturnal prosimian Microcebus none of the mid-long or short wavelength cones contain calbindin. In addition to primates, calbindin is absent in cones of other nocturnal species but is present in cones of diurnal species suggesting a difference in the role of calbindin possibly related to the adaptational states or other photoreceptor properties.

Adult↗

Sensitivity and rapidity of blood culture bottles in the detection of cornea organ culture media contamination by bacteria and fungi.

AIMS: To test the bactericidal activity of standard organ culture medium, and to compare the sensitivity and rapidity of blood culture bottles with conventional microbiological methods for detection of bacteria and fungi inoculated in a standard cornea organ culture medium. METHODS: The bactericidal activity of contaminated standard organ culture medium containing 100 IU/ml penicillin, 0.1 mg/ml streptomycin, and 0.25 micro g/ml amphotericin B was evaluated after 48 hours of incubation at 31 degrees C with five inocula of 14 bacteria. Two yeasts (Candida spp) and one Aspergillus were also tested. Contaminated media were then inoculated in three blood bottles (aerobic, anaerobic, fungal) placed in a Bactec 9240 automat; three conventional microbiological broths were the control. Changes in colour of organ culture medium and growth on conventional broth were screened daily by visual inspection. The sensitivity and rapidity of detection of contamination were compared between the three methods: blood bottle, conventional, and visual. RESULTS: Organ culture medium eradicated five bacteria irrespective of the starting inoculums: Streptococcus pneumoniae, Branhamella catarrhalis, Escherichia coli, Propionibacterium acnes, and Haemophilus influenzae. For micro-organisms where the medium was ineffective or bactericidal only (methicillin resistant Staphylococcus aureus, methicillin sensitive Staphylococcus aureus, Staphylococcus epidermidis, Staphylococcus haemolyticus, Pseudomonas aeruginosa, Acinetobacter baumannii, Bacillus subtilis, Klebsiella pneumoniae, Enterococcus faecalis, Candida albicans, Candida kruzei, Aspergillus fumigatus), the blood bottle, conventional, and visual methods detected microbial growth in 100%, 76.5%, and 70% of cases respectively. Mean detection time using blood bottles was 15.1 hours (SD 13.8, range 2-52). In cases of detection by the blood bottle method and the conventional method, the former was always faster: 95.5% against 65.2% detection within 24 hours (p=0.022) respectively. CONCLUSIONS: Blood bottles detect more efficiently and more rapidly a wider range of bacteria and fungi than the conventional microbiological method and the visual inspection of organ culture media.

Bacteria↗

Value of two mortality assessment techniques for organ cultured corneal endothelium: trypan blue versus TUNEL technique.

BACKGROUND/AIM: It is known that trypan blue staining is not a good predictor of loss of corneal endothelial cells (ECs) during organ culture. As it is primarily an indicator of membrane integrity, it would also not be expected to identify ECs undergoing apoptosis. The aim of this study was to determine the ability of the in situ TdT dUTP mediated nick end labelling (TUNEL) technique to detect cell death in the corneal endothelium caused by apoptosis during organ culture, compared with conventional vital staining with trypan blue. METHODS: 31 human corneas were organ cultured at 31C for 3-35 days. Staurosporine was used to induce apoptosis in five control corneas. The endothelium was assessed by trypan blue and by the in situ TUNEL technique. The percentages of trypan and TUNEL positive ECs were compared. Their links with sex, donor age, time from donor death and organ culture, initial and final EC density and cell loss were studied. RESULTS: TUNEL stained ECs were observed in all corneas. TUNEL positive ECs were mostly located either in corneal folds or at the periphery of corneal folds showing central shedding. The mean percentage of cell death at the end of storage, assessed by the trypan blue technique, was 1.47% (SD 2.63, range 0.03-12); assessed by the TUNEL technique it was 12.7% (SD 16.4 range 0.6-65.5). There was a significant correlation between the two techniques (r = 0.7, p<0.001). The percentage of TUNEL stained ECs was correlated negatively with EC density at the end of storage (r = -0.47, p <0.005) and positively with percentage EC loss during storage (r = 0.46, p < 0.05). CONCLUSION: This study demonstrates that organ cultured corneas systematically carry non-viable ECs that are implicated in cell death by apoptosis and go undetected when trypan blue staining is used. Because the in situ TUNEL assay detects earlier events in the cell death process than does trypan blue, it should be used to quantify endothelial viability, especially for experiments with new storage media.

Adult↗

Cornea procurement from very old donors: post organ culture cornea outcome and recipient graft outcome.

AIM: To study the suitability of corneas from very old donors for graft after banking and their clinical and endothelial outcomes in recipients. METHODS: 419 corneas stored in organ culture were divided into group 1, donors under 85 years (330 corneas) and group 2, "very old" donors aged 85 years and over (89 corneas). Endothelial cell density (ECD) before and after organ culture, discard rate before and after storage, and clinical and endothelial outcomes of the 196 penetrating keratoplasties (PKP) (158 in group 1 and 38 in group 2) were compared in a prospective longitudinal study. RESULTS: Initial ECD was lower in group 2 than in group 1 and elimination for low ECD was more frequent in group 2 (respectively 38% v 20.2%, p=0.001). At the end of storage, because very old corneas lost fewer ECs than younger ones (respectively 4.2% v 9.5%, p=0.022), ECD was comparable between the two groups. The corneas of very old donors had a poorer macroscopic appearance at procurement and during surgery. Despite this, in grafted patients, overall graft survival in groups 1 and 2 (respectively 87.4% v 80.6%, p=0.197), visual acuity, and ECD did not differ at completion of the study (mean follow up 25 months). CONCLUSION: This study suggests that endothelial cell count during banking ensures that functional and cellular results of PKPs are not dramatically influenced by very old donor age. Considering Europe's ageing population, the very elderly should not be deemed off limits for corneal procurement.

Adolescent↗

[Corneal harvesting from donors over 85 years of age: cornea outcome after banking and grafting].

PURPOSE: To study the suitability of corneas from very old donors for graft after organ culture and their clinical and endothelial outcomes in recipients after perforating keratoplasty. METHODS: We stored 419 corneas at 31 degrees C for 13.1 +/- 4 days (mean +/- SD) and then divided them according to donor age: group 1, donors under 85 years of age (n=3 3 0, 79%, 16-84 years old), and group 2, donors over the age of 85 (n=8 9, 21%, 85-100 years old). Endothelial density at the time of harvest and before and after organ culture, rates of suitability for grafting, and clinical and endothelial outcomes of the 196 keratoplasty procedures were compared in a prospective longitudinal study of the 2 groups, with a mean follow-up of 25 months. The corneas were grafted with no pre-established policy on matching with the age of the receiver. Statistical analysis was carried out on SPSS 10.0: Chi(2), Student t test, and Kaplan Meier survival curves. RESULTS: The average age of the donors was 72.1 +/- 16.7 years. The macroscopic aspect of the corneas was judged to be of slightly lower quality in group 2. No statistically significant difference was found in overall suitability for transplantation (group 1, 45% vs group 2, 54%, p=0.17) but elimination for low endothelial density was more frequent in group 2 (67% vs 39%, p=0.001). Cell density at the beginning of organ culture was lower in very old corneas than in younger corneas (respectively, 2116 +/- 368 vs 2 311 +/- 360 cell/mm(2), p=0.002) but no difference was apparent at the end of organ culture (respectively, 2 011 +/- 285 vs 2 090 +/- 296, p=0.12) because very old corneas lost fewer cells than younger ones (respectively, 5.6% vs 10.0%, p=0.001). There was no correlation between donor/receiver age (r=0. 337) but group 1 corneas were slightly more frequently allotted to receivers with normal endothelium (p=0.019). During surgery, the two groups did not differ in terms of the macroscopic aspect of the grafts. In the 196 grafted patients, and without age-matching, overall graft survival (86% vs 79%, p=0.275), visual acuity, and endothelial density (1 194 +/- 469 vs 1098 +/- 545 cells/mm(2), p=0.387) did not differ at the completion of the study. DISCUSSION: The corneas from very old donors were macroscopically of poorer quality and had a lower cellular endothelial density at harvesting, but these differences disappeared after organ culture because of greater cell loss in corneas from younger donors. Selection by organ culture ensures that functional, anatomical, and cellular results are not influenced by very old donor age. CONCLUSION: Considering the aging population in countries with a high standard of living, the techniques available for selecting corneas based on endothelial quality, and the increasing need for corneal grafts, the very old age should not be deemed off-limits for corneal harvesting.

Adolescent↗

[Use of a pair of blood culture bottles for sterility testing of corneal organ culture media].

PURPOSE: To test the effectiveness and rapidity of a pair of blood culture bottles in the diagnosis of bacterial and fungal contamination of corneal organ culture media. MATERIAL: and methods: Seven hundred and sixty one microbiological analysis of storage media (Inosol(R) and Exosol(R), Opsia, Toulouse, France), sampled in all phases of the organ culture at 31 degrees C of 410 consecutive corneas, were analyzed. Each medium was inoculated in a pair of Bactec Plus Aerobic/F(R) and Bactec Lytic/10 Anaerobic/F(R) blood bottles (Becton Dickinson, Cockeysville, MD) and placed in a Bactec 9240 incubator for 14 days at 37 degrees C and in a Sabouraud broth at 20 degrees C. Changes in color or turbidity of storage media were evaluated daily at the corneal bank. Recipients were screened after graft for signs of infection. RESULTS: The overall contamination rate was 2.4% (18/761). Contamination was detected in less than 1 day in 78% (14/18) and in less than 2 days in 94% (17/18). Positivity of the microbiological controls of starting media preceded medium color changes in 10 out of 14 cases. Bactec blood bottles allowed detection of bacteria as well as Candida sp. yeasts. DISCUSSION: The use of a pair of aerobic and anaerobic blood culture bottles is a simple, effective and rapid method for the diagnosis of a wide range of microbiological contaminations of organ-cultured corneas during banking. CONCLUSION: The validation of this protocol will require a prospective study to compare it with the conventional microbiological method.

Aerobiosis↗

[Automated analyser of organ cultured corneal endothelial mosaic].

PURPOSE: Until now, organ-cultured corneal endothelial mosaic has been assessed in France by cell counting using a calibrated graticule, or by drawing cells on a computerized image. The former method is unsatisfactory because it is characterized by a lack of objective evaluation of the cell surface and hexagonality and it requires an experienced technician. The latter method is time-consuming and requires careful attention. We aimed to make an efficient, fast and easy to use, automated digital analyzer of video images of the corneal endothelium. METHODS: The hardware included a PC Pentium III ((R)) 800 MHz-Ram 256, a Data Translation 3155 acquisition card, a Sony SC 75 CE CCD camera, and a 22-inch screen. Special functions for automated cell boundary determination consisted of Plug-in programs included in the ImageTool software. Calibration was performed using a calibrated micrometer. Cell densities of 40 organ-cultured corneas measured by both manual and automated counting were compared using parametric tests (Student's t test for paired variables and the Pearson correlation coefficient). RESULTS: All steps were considered more ergonomic i.e., endothelial image capture, image selection, thresholding of multiple areas of interest, automated cell count, automated detection of errors in cell boundary drawing, presentation of the results in an HTML file including the number of counted cells, cell density, coefficient of variation of cell area, cell surface histogram and cell hexagonality. The device was efficient because the global process lasted on average 7 minutes and did not require an experienced technician. The correlation between cell densities obtained with both methods was high (r=+0.84, p<0.001). The results showed an under-estimation using manual counting (2191+/-322 vs. 2273+/-457 cell/mm(2), p=0.046), compared with the automated method. CONCLUSIONS: Our automated endothelial cell analyzer is efficient and gives reliable results quickly and easily. A multicentric validation would allow us to standardize cell counts among cornea banks in our country.

Aged↗