ABSTRACT
Some bone marrow transplant patients who require multiple platelet transfusions as a consequence of post-transplant thrombocytopenia become refractory to these transfusions. As the spleen is the primary site of destruction for senescent and damaged platelets, splenectomy is a potential therapy for persistent thrombocytopenia. Scintigraphy with 111In-labeled platelets has been used to identify increased splenic sequestration and destruction in various platelet disorders, especially idiopathic thrombocytopenic purpura, before consideration of therapeutic splenectomy, but this technique has not been widely described in platelet transfusion refractory bone marrow transplant patients. We report on the results of 111In-labeled platelet scans in two such patients and review the pertinent literature in relation to the possible benefits and limitations of this scanning technique.
Subject(s)
Blood Platelets , Bone Marrow Transplantation/adverse effects , Indium Radioisotopes , Platelet Transfusion , Thrombocytopenia/diagnostic imaging , Adult , Blood Donors , Humans , Liver/diagnostic imaging , Male , Radionuclide Imaging , Spleen/diagnostic imaging , Splenectomy , Thrombocytopenia/etiology , Thrombocytopenia/therapy , Treatment FailureABSTRACT
Malignant melanoma of the nasopharynx and paranasal sinuses is relatively rare. We retrospectively reviewed the magnetic resonance appearance of five cases and correlated this with the histopathological appearance. In all cases, the magnetic resonance (MR) images clearly demonstrated the precise anatomic extent of the tumor and were sensitive in assessing intracranial extension and invasion into surrounding structures, including the skull base. Three cases were reviewed for histopathological evidence of melanin, hemosiderin, and acute hemorrhage. One case was reviewed for melanin and hemorrhage only. The findings in this series suggest that melanoma of the nasopharynx and paranasal sinuses have extremely variable amounts of paramagnetic substances, both melanin and products of hemorrhage. T1 shortening appears to be more often a reflection of the paramagnetic effects associated with products of hemorrhage rather than the presence of melanin.
Subject(s)
Magnetic Resonance Imaging/methods , Melanoma/diagnosis , Nasopharyngeal Neoplasms/diagnosis , Nose Neoplasms/diagnosis , Acute Disease , Aged , Evaluation Studies as Topic , Female , Gadolinium , Hemorrhage/pathology , Humans , Male , Melanoma/pathology , Melanoma/secondary , Middle Aged , Nasopharyngeal Neoplasms/pathology , Nasopharyngeal Neoplasms/secondary , Neoplasm Recurrence, Local/diagnosis , Neoplasm Recurrence, Local/pathology , Nose Neoplasms/pathology , Nose Neoplasms/secondary , Paranasal Sinus Neoplasms/diagnosis , Paranasal Sinus Neoplasms/pathology , Paranasal Sinus Neoplasms/secondary , Prognosis , Retrospective StudiesABSTRACT
Magnetic resonance imaging (MRI) and computed tomography (CT) were performed in 40 patients with a variety of cardiovascular diseases. These imaging modalities were compared to investigate their relative value in the assessment of cardiovascular diseases. Of these 40 patients, 7 were found by CT to have detectable cardiovascular calcifications. These patients included one calcified mitral stenosis, one calcified coronary artery, one calcified type B aortic dissection, two calcified myocardial infarctions, and two patients with calcific pericarditis. In several cases, MRI was misleading because of difficulty in detecting calcifications. We present a series of cases illustrating a limitation of MRI in identifying diagnostically and clinically important cardiovascular calcifications.