Teisuke Hashimoto

Japanese consensus guidelines for pediatric nuclear medicine. Part 1: Pediatric radiopharmaceutical administered doses (JSNM pediatric dosage card). Part 2: Technical considerations for pediatric nuclear medicine imaging procedures.

Abstract The Japanese Society of Nuclear Medicine has recently published the consensus guidelines for pediatric nuclear medicine. This article is the English version of the guidelines. Part 1 proposes the dose optimization in pediatric nuclear medicine studies. Part 2 comprehensively discusses imaging techniques for the appropriate conduct of pediatric nuclear medicine procedures, considering the characteristics of imaging in children.

Hypergalactosemia in early infancy: Diagnostic strategy with an emphasis on imaging

Background:  Portosystemic shunt is one of the main causes of persistent hypergalactosemia without enzyme deficiency, but the diagnostic imaging strategy has not yet been established. The purpose of the present study was to establish a diagnostic imaging strategy.

Usefulness of 18F-Fluorodeoxyglucose Positron Emission Tomography for Follow-Up of 13-cis-Retinoic Acid Treatment for Residual Neuroblastoma After Myeloablative Chemotherapy.

Abstract 13-cis-retinoic acid (13-cis-RA) treatment is used as a second-line treatment for residual or recurrent neuroblastoma. However, determining the duration of 13-cis-RA treatment for residual and recurrent neuroblastoma can be a problem because it is difficult to evaluate the effectiveness of the treatment. We performed 13-cis-RA treatment to remove residual active neuroblastoma cells in an 8-year-old boy with stage 4 neuroblastoma that developed from a left sympathetic ganglion and had been treated with chemotherapy, surgery, autologous peripheral blood stem-cell transplantation, and radiotherapy. 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET) and iodine-123 metaiodobenzylguanidine (123I-MIBG) scintigraphy obtained immediately before 13-cis-RA treatment both showed positive findings in the area of the primary lesion. At 18 months after 13-cis-RA treatment, there was accumulation on 123I-MIBG scintigraphy but no uptake on 18F-FDG-PET, and 13-cis-RA treatment was suspended. The patient has been in complete remission for 3 years. In comparing the effectiveness of the 2 imaging modalities for monitoring the response to 13-cis-RA treatment, we considered that 18F-FDG-PET was superior to 123I-MIBG scintigraphy because 18F-FDG-PET images were not affected by the cell differentiation induced by 13-cis-RA treatment in our case. Thus, 18F-FDG-PET was useful for determining the treatment response and outcomes. We have reported a case of residual neuroblastoma treated with differentiation-inducing 13-cis-RA therapy. Different results were produced with 18F-FDG-PET and 123I-MIBG scintigraphy. The cessation of 13-cis-RA treatment was based on 18F-FDG-PET findings and there has been no relapse for 3 years.

Narrow Duplicated Internal Auditory Canal: A Rare Inner Ear Malformation With Sensorineural Hearing Loss

Anarrow duplicated internal auditory canal (IAC) is a very rare congenital inner ear malformation, with only 5 cases (to our knowledge) reported in the literature. 1-5 A 14-year-old girl with unilateral sensorineural hearing loss (SNHL) showed 2 narrow 1 mm) bony canals in the inner ear portion of the left temporal bone on computed tomograms (CTs). The anterior canal continued to the bony canal of the facial nerve, and the posterior canal continued to the cochlea. Other than a lack of development of the canal for the cochlear nerve, the cochlea was normal. High-resolution magnetic resonance images (MRIs) revealed a single thin cranial nerve located in the anterior canal. However, a cranial nerve was not found in the posterior canal. Therefore, a diagnosis of a unilateral narrow duplicated IAC with a hypoplastic vestibulocochlear nerve and vestibular-semicircular canal malformation was made. Computed tomography plays an important role in the evaluation of the bony structure; however, assessment of the neural contents on MRIs is important for the appropriate diagnosis and treatment of patients with a narrow duplicated IAC. We report a case of a unilateral narrow duplicated IAC, with a particular emphasis on the imaging findings of thin-slice high-resolution CTs and MRIs.

Oncocytic carcinoid of the kidney positively detected by I-131 MIBG scintigraphy.

The occurrence of oncocytic carcinoids in the kidney is extremely rare. The present case involves intractable hypertension with high-blood adenocorticotropic hormone (ACTH) values. A tumor was observed in the right kidney, and an abnormal accumulation was identified in the mass from I-131 metaiodobenzylguanidine scintigraphy. Surgery resulted in an initial diagnosis of oncocytoma. However, problem was finally diagnosed as the oncocytic carcinoid by supplemental pathologic examinations. Although oncocytomas are common renal tumors, if an oncocytoma is associated with hypertension or endocrine abnormalities, it is important to consider the possibility of oncocytic carcinoid and to perform additional pathologic examinations.