Abstract Plasmacytomas are a localized proliferation of plasma cells in the bone marrow and are less frequently seen in extraosseous organs or tissues. Extraosseous plasmacytoma is a rare malignant neoplasm and constitutes 3–5% of all plasma cell neoplasms. In this article, we describe a case of a patient with extraosseous plasmacytoma of the maxilla and the related computed tomography (CT) and magnetic resonance imaging (MRI) findings.
Contrast enhanced CT was performed in seven patients with pancreatic disease (chronic pancreatitis, n = 3; pancreatic head cancer, n = 2; mucin-producing pancreatic tumor, n = 2) who showed dilation of the main pancreatic duct (MPD) Minimum intensity projection (Min-IP) images of the pancreas were obtained using multi-projection volume reconstruction (MPVR) software by selecting an oblique slab that contained the entire MPD. Curved reformation (CR) images were obtained using multiplanar reformation (MPR) software by tracing the MPD on the Min-IP image. Both Min-IP images and CR images clearly showed the dilated main pancreatic duct in all seven patients. In three of the seven, obstruction of the MPD in the pancreatic head and the cause of obstruction (tumor mass, n = 2; caliculus, n = 1) were also clearly seen. Min-IP and CR images seem to be useful for the diagnosis of pancreatic diseases.
Purpose: Sialolithiasis is one of the most prevalent large obstructive disorders of the submandibular glands.The aim of this study was to investigate submandibular sialolithiasis with computed tomography (CT) and scintigraphy, with a particular focus on the relationship between CT values of the submandibular glands and their excretion rate.Materials and Methods: Fifteen patients with submandibular sialolithiasis who underwent CT and salivary gland scintigraphy were included in this study.The relationship between the CT values of submandibular glands with and without sialoliths and salivary gland excretion measured using salivary gland scintigraphy was statistically analyzed.Dynamic images were recorded on the computer at 1 frame per 20 seconds.The salivary gland excretion fraction was defined as A (before stimulation test [counts/frame]) / B (after stimulation test [counts/frame]) using time-activity curves.results: The CT values in the submandibular glands with and without sialoliths was 9.9±44.9Hounsfield units (HU) and 34.2±21.8HU, respectively (P = .233).Regarding the salivary gland excretion fraction using scintigraphy, the A/B value in the submandibular glands with sialoliths (1.09±0.23)was significantly lower than in the submandibular glands without sialoliths (1.99±0.57,P = .000).Conclusion: Assessments of the CT values and the salivary gland excretion fraction using scintigraphy in the submandibular glands seem to be useful tools evaluating submandibular sialolithiasis.
Supraophthalmic intraarterial chemotherapy has not become popular due to a high incidence of damage to the normal brain and eye. This damage is due to inhomogeneous distribution of the agent secondary to streaming and other flow-related phenomena. To try to minimize this complication, the authors developed a catheter and studied different infusion techniques. A 4.5-F catheter tapered to 2.5 F was used to perform supraophthalmic intraarterial chemotherapy in 26 patients with malignant gliomas. Forty-one of 45 catheterizations were successful. In 17 patients (20 procedures), technetium-99m hexamethyl-propyleneamine oxime (HMPAO) was then injected through the catheter and single photon emission computed tomography was performed to assess the cerebral distribution of the radiopharmaceutical with either a pulsatile or continuous infusion technique. Diffuse and relatively homogeneous distribution of Tc-99m HMPAO was observed with fast pulsatile infusion (10 of 10 procedures); however, inhomogeneous distribution was mostly seen with slow continuous infusion (eight of 10 procedures).
Nonlinear optical properties of perylene derivatives were studied by femtosecond Z-scan technique. 3,4,9,10-Perylenetetracarboxylic dianhydride (PTCDA), 3,4,9,10-perylenetetracarboxylic diimide (PTCDI), and perylene-66 (dibenzthiophenoperylene-N,N'-dicyclohexylimide), were studied. Tetrahydrofuran was used as a solvent for perylene- 66. The solubility of PTCDA and PTCDI is very poor. Their colloidal solution was prepared by the irradiation of the third harmonics of a pulsed YAG laser to opaque suspension of PTCDA and PTCDI. Transparent colloidal solution was obtained within 50 minutes of UV irradiation. Colloidal solution of quinacridone was also studied. Two-photon absorption cross sections of these dyes were measured by open aperture Z-scan method using a femtosecond laser. The dependence of two-photon cross section on laser wavelength was measured in the wavelength range of 780-820 nm.
Purpose: To present characteristic findings of Tc-99m hydroxymethylene diphosphonate (HMDP) scintigraphy, computed tomography (CT), and magnetic resonance (MR) imaging for osteonecrosis in the mandible, especially osteoradionecrosis (ORN) and medication-related osteonecrosis of the jaw (MRONJ).Materials and Methods: Thirteen patients with MRONJ and 7 patients with ORN in the mandible underwent Tc-99m HMDP scintigraphy, CT, and MR imaging (T1-weighted images [T1WI], T2-weighted images [T2WI], short inversion time inversion recovery images [STIR]), diffusion-weighted images [DWI], and apparent diffusion coefficient [ADC] mapping).The associations of scintigraphy, CT, and MR imaging findings with MRONJ and ORN were analyzed using the chi-square test with the Pearson exact test.Results: Thirteen patients with MRONJ and 7 patients with ORN in the mandible showed low signal intensity on T1WI and ADC mapping, high signal intensity on STIR and DWI, and increased uptake on scintigraphy.Periosteal bone proliferation on CT was observed in 69.2% of patients with MRONJ (9 of 13) versus 14.3% of patients with ORN (1 of 7) (P = 0.019). Conclusion:This study presented characteristic imaging findings of MRONJ and ORN on scintigraphy, CT, and MR imaging.Our results suggest that CT can be effective for detecting MRONJ and ORN. (
Abstract Background Adenocarcinoma not otherwise specified (NOS) is an uncommon malignant minor salivary gland tumor. We report gallium-67 SPECT/CT and diffusion-weighted MRI (DWI) in the palatal tumor, especially a rare case with adenocarcinoma NOS. Case presentation An 85-year-old female patient presented with swelling on the palate within 3 months. DWI and apparent diffusion coefficient (ADC) maps indicated high and low signal intensities on the lesion, respectively. ADC value of the lesion was 0.58 × 10 –3 mm 2 s −1 . Gallium-67 SPECT/CT showed increased uptake on the lesion and no metastasis. The maximum SUV for the palatal lesion was 7.36. Histopathological diagnosis by a biopsy was adenocarcinoma NOS. Conclusion The gallium-67 SPECT/CT and DWI should be effective for assessment of the palatal tumor.
