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L Chamot

Publications and source records attributed to L Chamot.

At least 19 recordsLinked to original sources
PubMed2003

[Choroidal melanoma in neurofibromatosis type 2: description of a case].

To the best of our knowledge this is the first description of a choroidal melanoma with documented growth in neurofibromatosis type 2 (NF2). A 20-year-old patient with NF2 presenting deafness due to bilateral acoustic neurinomas and unilateral amaurosis due to a meningioma of the optic nerve developed a pigmented parapapillary choroidal tumor. Despite signs indicating the diagnosis of a melanoma, periodic observation was chosen in order to postpone functional amputation following optic nerve irradiation. The tumor growth was slow during the 5 years that followed, and once progression became rapid, the tumor was treated by accelerated proton beam radiotherapy. One year later, visual acuity diminished due to actinic optic neuropathy and was stabilized at 0.3 for the 2 following years. The tumor presented objective signs of regression, and no sign of metastatic disease was observed. The therapeutic approach in this case provided local control of the tumor while preserving useful visual function.

Adult↗
PubMed2001

Maximizing local tumor control and survival after proton beam radiotherapy of uveal melanoma.

PURPOSE: This study reports local tumor control and survival after proton beam radiotherapy (PBRT) of uveal melanoma. It identifies the risk factors for local tumor-control failure and for ocular tumor-related death. It presents the improvements implemented to increase the rate of local tumor control, and compares the survival rate of patients with locally controlled tumors to those of patients who had to receive a second treatment. PATIENTS AND METHODS: We have treated 2,435 uveal melanomas with PBRT between March 1984 and December 1998. Data were analyzed as of September 1999. Patients' age ranged from 9 to 89 years; there were 1,188 men and 1,247 women. The largest tumor diameter ranged from 4 to 26 mm, and tumor thickness from 0.9 to 15.6 mm. Median follow-up time was 40 months. RESULTS: Local tumor control probability at 5 years was improved from 90.6 +/- 1.7% for patients treated before 1988, to 96.3 +/- 0.6% for patients treated between 1989 and 1993, and became 98.9 +/- 0.6% for patients treated after 1993. Among 2,435 treated patients, 73 (3%) had to receive a second treatment because of tumor regrowth. Cause-specific survival at 10 years was calculated to 72.6 +/- 1.9% for patients with controlled tumors compared to 47.5 +/- 6.5% for those with recurrent tumors. CONCLUSION: Reduced safety margins, large ciliary body tumors, eyelids within the treatment field, inadequate positioning of tantalum clips, and male gender were identified to be the main factors impairing local tumor control. The improvement of local tumor control rate after 1993 is attributed to changes implemented in the treatment procedure. Our data strongly support that the rate of death by metastases is influenced by local tumor control failure: improvement of the local tumor control rate results in a better survival rate.

Adult↗
PubMed1999

Adenocarcinoma of the nonpigmented ciliary body epithelium: report of a rare case.

Acquired tumours of the nonpigmented ciliary body epithelium are rare. We present herein a case of low-grade adenocarcinoma in order to stress the problems related to the clinical diagnosis. The tumour in our case was circumscribed, localised on the ciliary body, and nonpigmented. The height of the tumour, measured with ultrasound biomicroscopy, was 3.5 mm. The internal reflectivity of the tumor was homogeneous with low attenuation. The tumour was surgically excised with an uneventful iridocyclectomy. Both clinical presentation and preoperative examinations allowed to circumscribe the correct diagnosis which could be confirmed only with histology.

Adenocarcinoma↗
PubMed1998

Proton beam irradiation of choroidal hemangiomas.

PURPOSE: To present a large series of choroidal hemangiomas treated with proton beam irradiation and to describe the treatment outcomes. METHODS: We treated 54 eyes of 53 patients with choroidal hemangioma. The lesions consisted of 48 circumscribed hemangiomas and six diffuse hemangiomas in patients with Sturge-Weber syndrome. The total applied dose was 27.3 Gy in four eyes, 22.7 Gy in three eyes, and 16.4 Gy to 18.2 Gy in 47 eyes. RESULTS: The retina reattached within six months after treatment in all 54 eyes and no recurrence of the secondary retinal detachment occurred within the follow-up period of 6 months to 9 years. Tumors treated with the higher doses regressed faster than tumors treated with the lower doses, but radiation-induced complications of the optic nerve appeared in all four eyes treated with a total dose of 27.3 Gy. Of 31 eyes treated with 16.4 to 18.2 Gy and followed for more than 1 year, 22 had an improvement in their visual acuity, and nine retained the same visual acuity. At the last follow-up examination, the best-corrected visual acuity was 20/20 or better in nine eyes, 20/40 to 20/25 in 13 eyes, 20/100 to 20/50 in six eyes, and 20/200 or less in three eyes. CONCLUSIONS: Proton beam irradiation of choroidal hemangiomas appears to be a valid therapeutic alternative. A total proton dose ranging from 16.4 to 18.2 Gy applied in four daily fractions seems adequate to ensure local control of both tumor and secondary retinal detachment.

Adult↗
PubMed1996

Cobalt-60 treatment of choroidal hemangiomas.

PURPOSE: We investigated the therapeutic possibilities of gamma brachytherapy to improve the final functional results of eyes with choroidal hemangiomas, which are benign vascular tumors that can induce progressive impairment of visual acuity. METHODS: We treated 41 patients with choroidal hemangioma with cobalt-60 applicators. The lesions consisted of 39 circumscribed hemangiomas and two diffuse hemangiomas in patients with Sturge-Weber syndrome. Before treatment, visual acuity in the affected eye was 20/200 in ten patients, 20/200 to 20/50 in 17 patients, 20/40 to 20/25 in 11 patients, and 20/20 in three patients. All patients were symptomatic. The macula was infiltrated by the tumor in 12 eyes (29.3%). There was retinal detachment in 40 eyes (97.6%), cystoid edema in ten eyes (24.4%), subretinal fibrosis in eight eyes (19.5%), and areolar atrophy in two eyes (4.9%). RESULTS: After treatment, the retina was reattached in all eyes, and the tumor progressively transformed into a flat scar. The postirradiation macular lesions that we identified were pigment migrations in the macular region, subretinal fibrosis, and an areolar atrophic scar. We correlated the functional results at two, five, and ten years after treatment with the initial visual acuity, and with pre-existing and posttreatment macular lesions. CONCLUSIONS: Our results suggest that radiotherapy is a valuable therapeutic modality for choroidal hemangiomas, particularly in hemangiomas that involve the macula, and for tumors associated with bullous retinal detachment.

Adolescent↗
PubMed1996

[Value of indocyanine green videoangiography in differential diagnosis of nonpigmented tumors of the choroid].

BACKGROUND: Indocyanine green video-angiography (ICG) is a recent examination technique, its possibilities and limitations as far as intraocular tumours are concerned, haven't been fully explored yet. MATERIAL AND METHODS: We have studied 50 cases of non-pigmented choroidal tumours, including 14 cases of choroidal hemangioma's, 11 cases of posterior uveal metastases and 25 cases of non-pigmented melanoma's. RESULTS: Characteristic images were obtained when examining choroidal hemangioma's and, until a certain point, posterior choroidal metastases. Non pigmented melanoma's on the contrary, presented a great variety of different indocyanine green angiographic pictures. CONCLUSION: Indocyanine green video-angiography (ICG) has a definite value in the differential diagnosis of non-pigmented posterior choroidal tumours.

Angiography↗
PubMed1996

[Contribution of ultrasound biomicroscopy to conservative treatment of anterior uveal melanoma].

BACKGROUND: Ultrasound Biomicroscopy (UBM) is a new ophthalmological imaging technique essentially designed for the study of the anterior eye segment. Over the last 10 months, we've evaluated its contribution to the conservative treatment of anterior uveal melanoma's by means of accelerated proton beam irradiation. MATERIAL: Using UBM, we have examined 55 cases of uveal melanoma's, whose anterior border was situated at 6 mm or less from the limbus and that were consequently treated by proton beam irradiation. RESULTS: The presumed tumoral origin was the ciliary body's pars plicata in 13 cases and the pars plana or the choroid in 42 cases, 17 of which presented a tumoral invasion of the pars plicata. A pars plana detachment anterior to or surrounding the anterior tumoral border, was present in 22 cases. The height of the tumor could only be measured by UBM if it was less than 2.5 mm. Information gathered using UBM have contributed to an improvement of the therapy plan in 32 cases. CONCLUSION: Because of the strong attenuation of the high frequency ultrasound signal, UBM can only be used for the examination of intra-ocular structures situated in direct neighbourhood to the global wall. Despite this technical limitation, ist contribution to the planning of the conservative treatment of anterior uveal melanoma's by proton beam irradiation has appeared to be considerable.

Choroid Neoplasms↗
PubMed1995

[Familial uveal melanoma].

BACKGROUND: Familial uveal melanoma are rare and a few number of cases has been described in literature until now. An autosomal dominant inheritance was proposed. MATERIAL AND METHOD: From the 2169 patients examined and/or treated in the Jules Gonin Hospital for an uveal melanoma from 1969, we identified 11 patients from 9 families in which at least two members were affected. We compared the clinical data of the familial melanoma with those of the sporadic cases of our collective with the Kruskal-Wallis Tests. The following parameters were studied: age and sex of patients, largest and smallest tumor diameter, height and volume of tumor, distance between tumor and optic nerve and macula, distance of tumor to the equator. Age and sex were also compared with literature. RESULTS: Among the 11 patients, nine were treated with an accelerated proton beam, one with Cobalt60 applicator and one has been enucleated. The median age was 58 years among the probands and 54.6 years among the sporadic cases of the collective. Sex ratio is superposable between both groups: male 45.5%, female 54.5% among the probands and male 48.6%, female 51.4% among the sporadic cases. The comparison between both groups with the Kruskal-Wallis Tests did not show any significant statistical difference. CONCLUSION: An uveal melanoma occurring at least in two members of the same family is not due to chance alone. Genetic factors associated to external factors are probably responsable.

Adolescent↗
PubMed1994

[Metastases to the uvea: statistical study of 133 cases].

133 cases of uveal metastasis were reviewed. The study included 97 women and 36 men, aged 10 to 80 (mean 53.1). Breast carcinoma in women and lung carcinoma in men were the primary malignancies, which most frequently led to uveal metastasis. Metastasis from lung carcinoma were often diagnosed before the primary tumor. Survival from ocular diagnosis to death depends on the histological type of the primary tumor.

Adolescent↗
PubMed1993

Fundus changes associated with congenital hypertrophy of the retinal pigment epithelium.

The clinical characteristics and follow-up changes of 64 patients with solitary congenital hypertrophy of the retinal pigment epithelium were studied. Thirty-five of the patients were followed up for one to 14 years with serial fundus photography. Progressive increase of the hypopigmented part of the lesion was observed in 29 of the 35 patients who were followed up (82.8%). An enlargement of the lesion was seen in 26 of the 35 patients (74.3%). Two additional changes, that is, pigmented areas adjacent to congenital hypertrophy of the retinal pigment epithelium and linear streaks of the pigment epithelium, were documented. Pathogenetic mechanisms for the development of these changes remain unknown.

Adult↗
PubMed1992

[Treatment of eye tumors by accelerated proton beams. 7 years experience].

The therapeutic results of 1070 cases of intraocular tumors treated with an accelerated proton beam at the University Eye Clinic of Lausanne and at the Paul Scherrer Institute of Villigen are analysed. This total is composed of 981 cases of uveal melanomas treated by proton beam as first treatment modality, 42 cases of recurrent choroidal melanomas, 16 cases of conjunctival melanomas, 8 cases of choroidal hemangiomas, 18 cases of uveal metastases and of 5 other ocular tumors. The mortality rate at 5 years for tumors treated with an accelerated proton beam as first treatment modality was 13%, and the mortality rate of recurrent melanomas was 23%. The risk factor for life expectancy analysed with the Cox model pointed out that the largest tumor diameter, the width of the tumor, the presence of an extrocular extension and the age of the patient were the most significant parameters. The conclusions of this study are compared with those found in available literature.

Conjunctival Neoplasms↗
PubMed1992

[Treatment of exterior extension of choroid melanomas by accelerated proton beams].

Among the 934 patients with a choroidal melanoma treated in first intention with an accelerated proton beam since 1984, 41 (4.4%) presented an extrascleral extension, of which 11 were located anteriorly and 30 posteriorly. For these 30 cases, the diagnosis was made by B ultrasonography only when the volume of the extension was important, between 20 and 2280 mm3. The Cox model multi-variant analysis was used to study the statistically significant parameters in the development of an extrascleral extension. It appears that the maximal diameter of the intraocular tumor (p = 0.0012), the localisation of the anterior margin (p = 0.0304) and the age of the patients (p = 0.0097) are statistically meaningful. The 4 years' survival, studied with the Kaplan-Meier curves, is estimated at 60% for the patients with extrascleral extension and at 85% for the patients without. These results are similar to those of literature, whatever treatment is chosen (enucleation and radiotherapy, exenteration).

Adult↗
PubMed1988

[Report on the conservative treatment of melanoma of the uvea at the Lausanne University Ophthalmologic Clinic].

A great number of techniques are currently available for the conservative treatment of uveal melanomas: ocular applicators emitting gamma rays 60Co, 125I) or high-energy beta rays (106Ru/106Rh), light photocoagulation, surgical excision, and accelerated proton beam irradiation. Life expectancy following conservative treatment is equal to or better than that following enucleation. This is demonstrated by nonrandomized comparative studies, and by the authors' own long-term results following the conservative treatment of melanomas by 60Co applicators: mortality due to metastases of small melanomas was 3% (V = smaller than 10 x 10 x 3 mm), with medium-size melanomas it was 12% (V = 10 x 10 x 3-15 x 15 x 5 mm), and with large melanomas 21% (V = larger than 15 x 15 x 5 mm). Accelerated proton beam irradiation of uveal melanomas is currently the method of choice for the conservative treatment of uveal melanomas. The sharp boundaries of the irradiated zone, the uniformly distributed irradiation dose, and beam-splitting are the main advantages of this technique. During the last three years, 310 cases of uveal melanoma have been treated in Switzerland with an accelerated proton beam. Of these, 214 were followed up for more than one year. Eight patients (3.9%) died of metastases. Visual acuity was identical or superior to initial visual acuity in 60.3% of the cases, while 39.6% exhibited a deterioration of vision or a functional loss. Favorable results achieved by conservative treatment of uveal melanomas considerably limited the indications for enucleation, which is now only performed in exceptional situations.

Brachytherapy↗
PubMed1984

[Tumors and pseudotumors of the pigment epithelium].

Tumors and tumor-like lesions of the pigment epithelium of the iris, ciliary body, and retina are discussed with special emphasis on definitions and the various elements of help in the differential diagnosis. One of these lesions, hypertrophy of the retinal pigment epithelium, is classically described as non-progressive. However, we report here 4 cases with documented progression of various forms. The etiology and physiopathologic considerations are discussed. Although most tumors and pseudotumors of the ocular pigment epithelium are benign, malignant forms and various non-malignant, but progressive types can occur.

Adenocarcinoma↗
PubMed1981

Ocular and orbital complications after sclerosing injections in a case of a frontal cutaneous angioma.

A baby is treated for frontal cutaneous angioma by two sclerosing injections, the second injection giving rise to severe complications and life-long sequelae: total amaurosis of the right eye with eventual bulbar phthisis, sectorial iris necrosis and cataract formation, as well as ugly sunken cutaneous scarring of the right upper eye-lid, forehead and scalp. It is the only case we know of, where such complications occurred after craniofacial angioma treatment by sclerosing injections.

Blindness↗