32Phosphorus uptake test in choroidal melanomas, naevi and haemangiomas

Abstract

A considerable controversy has developed as to the value of the 32 p uptake test in the diagnosis of intraocular tumours. As Shields (1978) stated, clinicians who have great experience with this test have stressed its accuracy in differentiating benign from malignant intraocular tumours but have perhaps failed to stress its limitations adequately. On the other hand, some clinicians with authority have doubted the usefulness of the 32 p test. Their opinion, however, was not based on valid statistical data but on incidental findings of false-negative and false-positive results. Like any other diagnostic test in medicine, the a2p test is not 100% reliable, has its limitations and can only be evaluated by statistical analysis of controlled studies of sufficiently large numbers of patients. We had the opportunity to carry out an extensive study thanks to the cooperation of the ophthalmologists in the Netherlands and of the Netherlands Ophthalmic Research Institute.

CT-scan and intraocular tumours: detection and assessment of size and extrascleral growth of uveal melanomas

“…A false-positive diagnosis can lead to the enucleation of an eye with a benign turnout; with a false-negative diagnosis malignancy can be overlooked which should have been treated. Although 32p examination (Oosterhuis et al, 1980) and A-and B-scan ultrasonography (Till and Hauff, 1981) have reduced the percentage of false diagnoses, problems still remain, especially in the assessment of the invasion of epi-and extrascleral tissues (Farah et al, 1984;Shammas and Blodi, 1977;Manschot, 1981). High resolution thin slice CT-scan with axial, coronal and, if necessary, sagittal sections is found to be an important aid to the detection and assessment of extrascleral growth.…”

Differential diagnosis of small pigmented choroidal tumours

“…In the majority of patients without visual field defects or with relative scotomas on Goldmann kinetic perimetry, static perimetry was also performed. Isotopic examination with 32p was carried out in all patients as part of a systematic examination of patients with intra-ocular tumours (Oosterhuis et al, 1980). The prominence of the tumours is recorded, but the ophthalmoscopic aspect is not included as the aspect of the small, flat, pigmented tumours near the posterior pole of this study could equally well be consistent with a naevus with signs of secondary degeneration or a melanoma; ultrasonography was not performed as the results are inconclusive in the only slightly elevated turnouts; diaphanoscopy is not of value in the differential diagnosis as it is related to the degree of pigmentation and not to the degree of malignancy.…”

Scintimetric Detection of Choroidal Malignant Melanoma with [¹²³I]-5-Iodo-2-Thiouracil

“…The 32P uptake test is a reliable method for corroborating the diagnosis of choroidal me lanoma [1][2][3], Because of the low tissue pen etration of 32P. in the majority of patients surgical dissection of the conjunctiva is required in order to place the probe precisely on the scleral surface at the base of the tumor.…”