PubMed Health⌕ Search

Biomedical subjects

A Pechereau

Publications and source records attributed to A Pechereau.

At least 19 recordsLinked to original sources
PubMed2006

[Deep lamellar keratoplasty versus penetrating keratoplasty for keratoconus].

OBJECTIVE: To determine the advantages, safety, and accuracy of deep anterior lamellar keratoplasty (DLK) versus penetrating keratoplasty (PK) in terms of visual acuity, astigmatism, and endothelial preservation in corneal diseases with healthy endothelium. Of these candidates for keratoplasty, the study investigated keratoconus patients with no other ophthalmic abnormalities. MATERIALS AND METHODS: This comparative nonrandomized retrospective study investigated 22 patients with keratoconus requiring surgery, who underwent keratoplasty in the Nantes University Hospital between 1 June 2002 and 1 January 2004. Ten DLK, ten PK and two PK converted DLK cases were analyzed. Follow-up at 2 weeks and at 3, 6, 9, and 18 months is reported for visual acuity, astigmatism, pachymetry, specular microscopy, and intraocular pressure (IOP). Data are compared before and after surgery at each follow-up date. RESULTS: Preoperative visual acuity improved in both groups from 0.14+/-0.13 to 0.8+/-0.17 postoperatively. There was no significant difference between the two groups before and at each time after surgery for visual acuity and astigmatism (3.5+/-2 diopters in the PK group and 3+/-0.9 D in the DLK group). There was a statistical difference for IOP with two occurrences of increased IOP up to 30 mmHg in the PK group. Endothelial cell count analysis showed an immediate postoperative decrease of 10% in the DLK group (versus approximately 40% in the PK group), remaining rather stable the 1st year (-3.3%), although cell loss in the PK group declined up to 10% more at 18 months. DISCUSSION: With no statistical difference between the two groups for visual acuity and astigmatism, DLK is effective. It is safer than PK in terms of IOP disturbance (leading cause of graft failure) and endothelial cell loss. DLK converted into PK (16%) showed the same profile as first-intention PK. CONCLUSION: Despite very similar effectiveness, DLK in keratoconus surgery should be proposed rather than PK because it appears safer not only in the short term but also probably in the long term, with no risk of endothelial cell rejection.

Adult↗
PubMed1998

[Scale for evaluating desirable ametropia or eumetropia].

GOAL: The purpose of this study is to assess the degree of desirable ametropia in cataract surgery. MATERIAL AND METHODS: A scale for evaluation was created. It allows to measure the desired distance for a neat uncorrected vision (desired ametropia) after cataract surgery that presbyopic patients (monocular vision) would like to obtain. This scale helps to calculate the power of the intraocular lens to be implanted. The scale was shown to a series of 50 consecutive presbyopic patients. Refraction was the same in both eyes. The interest of patients in the evaluation of their desirable ametropia was measured on a scale from 0 to 5. RESULTS: Interest was good for 50% of patients (grade > or = 3). Mean distance desired by patients for a neat uncorrected vision was 1 meter. Preoperative myopia and hyperopia have no significantive influence upon the distance desired for a neat uncorrected vision. CONCLUSION: The choice of the power of the lens implanted during cataract surgery should take into account the patients' desires. An evaluation of the postoperative desirable ametropia should be systematic.

Activities of Daily Living↗
PubMed1997

[Does the dosage of mitomycin-C applied during filtering surgery of glaucoma vary with the individual surgeon?].

PURPOSE: The purpose of this study was to estimate the quantity of mitomycin-C contained in sponges prepared by different surgeons as compared to that in applicators of the type used in Schirmer's test graduation (5 x 5 mm). MATERIALS AND METHODS: Four surgeons each cut and prepared 10 sponges for intraoperative use according to their usual method. The same procedure was performed with 10 Schirmer's test graduations. Each sponge and each graduation was immersed in a solution of mitomycin-C 0.2 mg/ml, and the quantity of antibiotic (microgram) in each was calculated as the difference between wet and dry weight. RESULTS: The mean quantity (+/-SEM) of mitomycin-C contained in cut sponges was 9.6 +/- 4.4 micrograms (range 1.9-17.3), and differences between surgeons were statistically significant (p < 0.0001). The mean quantity of antibiotic in Schirmer's test graduation was 1.7 +/- 0.3 micrograms (range 1.1-2.5), and the differences between surgeons were not statistically significant (p = 0.79). CONCLUSION: The quantities of mitomycin-C contained in sponges prepared for glaucoma surgery differed for a given surgeon and between surgeons. Thus, variations in the doses applied to the sclera could account for certain complications due to mitomycin-C. The use of a Schirmer's test graduation improves predictability for the quantity of mitomycin-C applied to the sclera.

Antimetabolites↗
PubMed1996

[Epidemiological and clinical aspects of Stilling-Turk-Duane syndrome].

BASIS: In a retrospective study on 155 patients with Stilling-Turk-Duane's syndrome, we compare our results with those described in the literature. Particular focus was based on the different clinical entities observed. PATIENTS AND METHODS: Patients were selected from 8000 charts of cases of strabismus seen in the Ophthalmological Clinic of the CHU in Nantes between 1980 and 1995. An oculomotor assessment carried out for all of these patients allowed us to determine the clinical type according to Malbran's classification. Patients were classified on the basis of family history of oculomotor disorder and associated pathology. RESULTS: The incidence of this syndrome in the population of strabismic patients was 1.9%. The number of women affected was 83 (53.5%). The syndrome was unilateral in 121 cases (78.1%). The left eye (71.9%) was affected more frequently than the right. Clinical entities not described by Malbran's classification were found in 24% of cases. These were described and classified. The oculomotor disorder most frequently encountered was esotropia. The number of patients with a amblyopia was 51 cases (32.9%). The number of patients with a torticollis was 101 cases (65.1%). The number of cases with associated medical pathology was 38 (24.5%). This pathology was ocular in 17 cases (10,9%) and extra-ocular in 22 cases (14.2%). The number of patients with a family history of oculomotor disorder was 39 (22.2%) among which 9 (5.8%) had at least one family member with Stilling-Turk-Duane's syndrome. CONCLUSION: Data provided by this study allowed us to analyse the clinical and epidemiological features of the Stilling-Turk-Duane's syndrome. What is more, they allowed us to describe and classify clinical forms not described by Malbran's classification.

Adolescent↗
PubMed1996

[Optico-geometric axes of the eye: application to the alpha angle and its representatives. Review of the literature].

The different positions of the corneal reflex and the center of the pupil demonstrates the decentration of the ocular structures. The optic axis and the visual axis are different. They form a angle (defined as angle alpha) important for appreciation of strabismic deviation. This phenomenon is well-known since the nineteen century. This review discusses the different definitions of the optico-visual axes and angles (angle alpha, gamma, kappa, lambda). A possible clinical application is discussed.

Eye↗
PubMed1994

[Medial rectus stretching test in recurrent esotropia].

In oculomotor surgery, evaluation of muscle elongation is necessary before deciding on the operative plan. This is particularly important in recurrent esotropia where the motor problem is highly complex because of visco-elastic alterations caused by previous surgery. The study of a series of 132 cases of recurrent esotropia shows that weakening of the medial rectus almost always causes reduced muscle elongation, the extent of which is directly proportional to the amount of recession.

Esotropia↗
PubMed1993

[A case of Tolosa Hunt syndrome].

The authors review the clinical signs, results of investigations and clinical course under treatment of the Tolosa-Hunt syndrome; they illustrate their case presentation with a complete sequence of the imaging and the clinical and radiological findings of a case which fits the classical description found in the literature. They insist on the term of syndrome rather than disease because of the obvious diversity of anomalies encountered in this condition.

Adult↗
PubMed1992

[Monobloc PMMA lenses. Anteroposterior displacement of the implant as a function of the insertion diameter].

Data concerning the biomechanical properties of IOL are rare. A systematic study of these properties was performed in the "laboratoire de Mécanique des Structures" at the "Ecole Centrale de Nantes". The results of the anteroposterior displacement of the optical part of eleven posterior chamber lenses (all PMMA) which were subjected to a diameter reduction, are reported. The deplacement of the implants was very slight and the position of the posterior side was relatively anterior whatever the diameter of insertion. The clinical implications, especially concerning the posterior capsule, are discussed.

Biocompatible Materials↗
PubMed1989

[Postoperative secondary divergent strabismus. Statistical analysis of 160 consecutive exotropias].

Exotropias secondary to convergent squint surgery are fully different from primary exotropias. Their frequency appears to be largely variable according to the operative procedures. The computerized analysis of 160 consecutive exotropias reveals the compound nature of their motor impairments. In each case it is necessary to carry out a careful check up of various causal parameters, but the authors find they are not bound by simple correlations. In all cases an elongation reducing one or several muscles is noticed. Such anomalies are much more frequent and heavy than those observed in primary esotropias. Their iatrogenic origin is unquestionable. In 37% of the cases heavy capsular scars have been observed; their consequences on passive forces are obvious, but it is difficult to carry out their exact evaluation by the usual clinical tests. In that series the resulting surgical planning was made according to the various abnormal parameters had allowed the achievement of a good motor result in 89% of the cases. In 86% of the cases, only one additional operative procedure was necessary.

Esotropia↗
PubMed1986

[Spatial binocular adaptation in microtropia and orthotropia. Definition and method of measurement].

For a long time the problem of the functional recovery in convergent strabismus has been a hardly debated topic. For some authors, it is very rare; for others, on the other hand, the result is frequently achieved. Such disparities seem to be chiefly related to the tests used. The authors have selected 10 binocular tests and they carried out this scale in a prospective study in 100 cases of esotropias having normal moving performances following a medico-surgical management and in 20 normal cases. statistical correlations reveal that there is a very large disparity of "good answers" according to the tests; but there is no redundancy at all between them. Consequently for a relevant check up every single one is necessary. The total of "good scores" and differential values of ten tests allow to know the true state of binocular spatial adaptation. The statistical analysis shows that in secondary microtropias and orthotropias there is almost always an actual binocular spatial adaptation. Its level may be high, medium or low. The high margin is clearly different from the binocular scores in normal cases. Two events are very uncommon: a full recovery of binocular vision and the opposite condition of its complete suppression. The results of such a method give a clear explanation of conflicting opinions about the binocular evolution of convergent squints following medical and surgical management.

Adolescent↗
PubMed1985

[Statistical study of the basic angle and intensity of spasm in functional esotropia (surgical consequences)].

In esotropia surgery all statistical results give the correlation between the amount of the operative correction and the angle of deviation; but this last entity is without value, because a consistent deviation nearly ever exists in spite of protracted medical management; indeed it is usual to notice large spatial variations. In a prospective series of 122 cases the authors have carefully studied the basic angle, the amount of angular variations which give evidence of the strength of spasm, the deep narcosis angle and the muscle elongation test. The various statistical correlations are analyzed. It appears that the basic angle and the strength of spasm are two essential connected but distinct characteristics of innervational imbalance, and it is necessary to carefully evaluate each one. There exists a highly significant correlation between the degree of innervational troubles and the frequency of visco-elastic impairments. The authors make several statements about medical management, early surgery and one-step surgery. They give new guidelines for their operative plan with the Faden operation.

Anesthesia, General↗
PubMed1985

[Current epidemiology of strabismic amblyopia in France].

It is well known that good early management of squint prevents the appearance of functional amblyopia and, when it exists, allows a cure in more than 90% of cases. The authors report a series of 1 552 esotropias. Statistical analysis reveals that the present epidemiologic state of functional amblyopia is dismal. 47% of cases have an amblyopia in spite of 64.6% of children being previously treated. The mean age is 7 years 6 months. The therapeutic results after a 6 months range still shows 38% of poorly applied treatment, but 57% of well-managed patients recover normal visual acuity. The long range results (average 33 months) show that in 47% of cases the treatment was badly applied. On the contrary, 70% of patients having good management were successful. Two main reasons explain such a situation : firstly the lack of information and casualness of parents; and on the other hand faltering and unsuitable medical technics. The only real answer to such a problem is early medical management of every squint. According to the author's experience it seems that such a state is not a special feature of amblyopia epidemiology in the western part of France, but it is observed in the same way in many countries having high level medical care.

Age Factors↗
PubMed1983

[Cell density of the corneal endothelium after penetrating keratoplasty. A retrospective study by specular microscopy].

Endothelial cell density of 70 penetrating grafts and 11 lamellar keratoplasties was studied by specular microscopy. In perforating transplants, mean cell density was 1150 cells/mm2. No correlation could be established between cell counts and diagnosis or associated surgical procedures. Minimal cell density for a clear transplant appears to be of the order of 450 cells/mm2. In lamellar keratoplasties cell loss is reduced, and this may be one way to increase the proportion of clear grafts when endothelium is healthy.

Adolescent↗
PubMed1982

[Specular microscopy of the corneal endothelium during different methods of lens implant surgery (author's transl)].

The authors relate their experience with five types of I.O.L. A retrospective study had been done with a specular microscope in order to determine which way provokes the lowest endothelial cell loss. The less traumatic technique is E.C.C.E. with posterior chamber lens: cell loss is 10%. There is no difference between this method and conventional E.C.C.E. without implantation.

Cell Count↗
PubMed1982

[Surgical treatment of optical nystagmus (author's transl)].

Effective management improves the sensory-motor state of most optical nystagmus cases. Treatment is always medical and sometimes surgical. Previous complete sensory and motor examinations are necessary. A surgical cure is warranted by the extent of nystagmus, a torticollis, or when a squint is associated. The authors review the various clinical aspects, and their operative plan, which is simple in Kestenbaum's, more delicate in dissociated forms, convergence blockages and nystagmic squints. It is often very difficult in complex nystagmic impairments.

Diagnosis, Differential↗