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M N Burnier

Publications and source records attributed to M N Burnier.

24 records · Page 2Linked to original sources

The role of chorioretinal biopsy in the management of posterior uveitis.

BACKGROUND: The ideal management of intraocular inflammation may require a tissue diagnosis. Diagnostic vitrectomy is a well-established method for acquiring such tissue. However, in some patients, the diagnostic pathology is limited to the choroid and retina and vitrectomy may yield no useful information. In such cases, a more aggressive surgical approach to obtain tissue may be useful. METHODS: The authors performed chorioretinal biopsies on seven patients with progressive chorioretinal lesions of unknown etiology. Indications for biopsy included: (1) macular-threatening lesions unresponsive to therapy, (2) suspicion of malignancy, or (3) suspicion of an infectious etiology. In all cases, it was expected that the results would alter therapy or other aspects of clinical care. Preoperative visual acuity was 20/200 or worse in each eye biopsied with one or more peripheral chorioretinal lesions present. Biopsy specimens were divided into three parts and submitted for light and electron microscopy, immunohistochemistry, and tissue culture. RESULTS: On the basis of the biopsy findings, a diagnosis of multifocal choroiditis and subretinal fibrosis was rendered in three eyes, sarcoidosis in two eyes, and viral retinitis in two eyes. Therapy was changed in five patients. Final visual acuity was unchanged or improved in five eyes. Complications included the progression of lens opacity in all eyes and the development of phthisis in one eye that was extensively diseased preoperatively. CONCLUSION: Chorioretinal biopsy may provide useful information for determining the diagnosis and guiding the subsequent management of patients with progressive chorioretinal lesions of unknown etiology.

Adult↗

Immunohistochemistry of infiltrating lymphocytes in uveal malignant melanoma.

PURPOSE: To investigate using immunohistochemistry the unusual finding that tumor infiltrating lymphocytes (TIL) in uveal melanomas are associated with a higher mortality rate. METHODS: We performed immunohistochemistry for B and T lymphocytes on 80 uveal malignant melanomas, which previously had been reported to contain more than 100 TIL per 20 high-powered fields. In a second study of 90 patients, we counted the number of immunohistochemically stained T lymphocytes per 20 high-powered fields in uveal melanomas from 30 patients who survived at least 15 years after enucleation, from 30 patients who died with metastasis within 2 years, and from 30 patients who died with metastasis more than 10 years after enucleation. RESULTS: T cells predominated in 73.8% of the 80 patients, and B cells were more prevalent in 13.8%. T cells were usually scattered, and B cells were usually in clumps. Post-enucleation 18-yr mortality from metastasis was 73% for patients with either T- or B-cell predominance of their TIL. The mortality rate was 32% for patients with few TIL. The patients who survived at least 15 yrs after enucleation had fewer T lymphocytes infiltrating their uveal melanomas than the two groups of patients who died with metastasis. CONCLUSIONS: The pattern of the TIL was different for T and B cells in uveal melanomas. T-lymphocytic infiltration is associated with death due to metastasis.

B-Lymphocytes↗

Immunohistochemical evaluation of uveal melanocytic tumors. Expression of HMB-45, S-100 protein, and neuron-specific enolase.

The authors compared the immunohistochemical reactivity of 13 uveal nevi and 20 uveal melanomas for HMB-45, S-100 protein, and neuron-specific enolase (NSE) in formalin-fixed, paraffin-embedded sections. All 33 of the lesions were positive for HMB-45. The false-negative rates for S-100 protein and NSE were 21% and 18%, respectively. If only strongly positive reactions were considered, more than 50% of the tumors would be interpreted as negative for S-100 protein and NSE. Nevi stained with less intensity than melanomas using all three antibodies. The expression of HMB-45 appeared to be greater in active nevi than in inactive nevi. There was a weak association between S-100 protein reactivity and the ability of the uveal melanomas to metastasize (P = 0.1); however, the standard deviation of nucleolar area was a much better predictor (P = 0.02). These results indicate that pathologists will find HMB-45 to be a useful tool in differentiating uveal melanoma from nonmelanocytic tumors.

Antibodies, Monoclonal↗

Retinoblastoma. The relationship of proliferating cells to blood vessels.

In 150 retinoblastomas the authors found a uniform thickness of the cuff of viable retinoblastoma cells that surrounds blood vessels. The mean thickness was 98.7 microns with a standard deviation of 11.9 microns. The cross-sectional area of the cuff was negatively correlated with the mitotic activity in the cuff and positively correlated with the diameter of the central vessel. The mitotic activity in the cuff of cells was inversely related to the distance from the central blood vessel. When the cuff was divided into three concentric rings, the inner ring contained a mean of 6.2 mitotic figures, the middle ring contained a mean of 2.9 mitotic figures, and the outer ring contained a mean of 0.6 mitotic figures. This pattern of growth is similar to that observed in other rapidly growing neoplasms in humans and experimental animals. In these tumors this pattern results from reduction in oxygen tension with increased distance from the central blood vessel.

Blood Vessels↗

The role of ultrasound biomicroscopy in predicting the result of temporal artery biopsy in temporal arteritis patients: a preliminary study.

PURPOSE: Temporal artery biopsy is considered the gold standard for the diagnosis of temporal arteritis (TA). However, complications following this procedure may occur. The goal of this study is to evaluate if ultrasound biomicroscope (UBM) findings are useful in predicting the result (positive or negative) of temporal artery biopsy in patients with TA. METHODS: Twenty-six consecutive patients with clinical diagnosis of TA seen at the Department of Ophthalmology, Royal Victoria Hospital, Montreal, Canada, were involved in this study. All patients were submitted to UBM before temporal artery biopsy. Eight patients presented histopathologic findings consistent with the diagnosis of TA. Thus, UBM findings of these patients were compared with those from 18 patients with negative biopsy. On UBM we searched for the presence of a hypoechoic effect surrounding the walls of the temporal arteries, the so-called halo sign, as well as an intra-arterial middle reflexive filling, the so-called intra-arterial filling. RESULTS: The halo sign and/or the intra-arterial filling were found in 8 (100%) of 8 patients with biopsy-proven TA. However, 10 (55.5%) of 18 patients with a negative biopsy presented one or both of these two UBM findings. On the other hand, the absence of these two parameters on the UBM of a patient with TA strongly suggests that the temporal artery biopsy will be negative (negative predictive value=100%). CONCLUSIONS: This preliminary work suggests that UBM may play a role in predicting a negative result of the temporal artery biopsy in patients with TA. In the present series approximately 30% of the patients could be spared this surgical procedure and its possible complications.

Aged↗