Magnetic Resonance Imaging

A patient with suspected uveal melanoma died 18 months after refusing all treatment. Since this disease rarely goes untreated, its undeterred spread is of clinical interest. At the request of the patient's family and physician, we set out to verify the type, location, and extent of the tumor, and the cause of death. Post-mortem magnetic resonance imaging (MRI) of the patient's head, followed by dissection and microscopic examination confirmed the diagnosis of primary uveal melanoma. There were large masses in the frontal part of the cranium which apparently had metastasized from the primary uveal tumor via vascular or lymphatic pathways since there were no direct extensions of the primary tumor beyond the orbital musculotendinous cuff. Metastases found in the liver, kidney, and vertebrae, in the absence of cervical, thoracic, and abdominal lymph node involvement, indicated the likelihood of hematogenous spread although small subpleural metastases were found in the lung. The cause of death appeared to be acute myocardial infarction due to obstruction of both coronary arteries and was unrelated to the malignancy.Although MRI has been proposed as an important tool for diagnosing uveal melanoma, our findings indicate the need for caution. Misleading signal intensities resulting from variable pigmentation in these tumors impair diagnosis. o

show abstract

Influence of paramagnetic melanin on the MRI contrast in melanoma: a combined high‐field (11.7 T) MRI and EPR study

Godechal

Mignion

Karroum

et al. 2014

Contrast Media & Molecular

View full text Add to dashboard Cite

Melanoma is the most dangerous form of skin cancer and its incidence is rising each year. Because the current methods of diagnosis based on the visual aspect of the tumor show limitations, several new techniques are emerging to help in this diagnosis, amongst which are magnetic resonance imaging (MRI) and electron paramagnetic resonance (EPR). The origin of the typical contrast pattern observable in melanoma in T1 - and T2 -weighted images remains to be elucidated and is a source of controversy. In addition, melanin could create sufficient magnetic inhomogeneities to allow its visualization on T2 *-weighted images using high-field MRI. In order to elucidate the possible role of melanin in the MRI contrast of melanoma, the present study was designed to correlate the paramagnetic content in melanin pigment to the contrast on T1 -, T2 - and T2 *-weighted images. MR images were obtained in vivo at 11.7 T using four types of experimental tumors with different pigmentations (B16, HBL, LND1 melanomas and KHT sarcomas). The paramagnetic content in melanin pigment was measured by EPR. No significant correlation was observed between the content in melanin and the relaxation times T1 , T2 and T2 *, emphasizing that the presence of pigment alone has negligible effect on the MRI contrast.

show abstract

scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.

Contact Info

customersupport@researchsolutions.com

10624 S. Eastern Ave., Ste. A-614

Henderson, NV 89052, USA

This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.

Blog Terms and Conditions API Terms Privacy Policy Contact Cookie Preferences Do Not Sell or Share My Personal Information

Made with 💙 for researchers

Part of the Research Solutions Family.

Magnetic Resonance Imaging

Cited by 19 publications

References 24 publications

Does the Melanin Content of Uveal Malignant Melanomas Correlate With Their Magnetic Resonance Imaging Appearance?

Does the Melanin Content of Uveal Malignant Melanomas Correlate With Their Magnetic Resonance Imaging Appearance?

Untreated uveal melanoma and its metastatic spread: A case report

Influence of paramagnetic melanin on the MRI contrast in melanoma: a combined high‐field (11.7 T) MRI and EPR study

Contact Info

Product

Resources

About