To investigate MR artifacts induced by metallic implants, scans were obtained using both the ferromagnetic Drake lip and the non ferromagnetic Yasargil clip. Scan were taken through the area of clips using geometrical phantom. The MRI was performed by spin echo technique and gradient echo technique on both 2.0T and 0.5T MR unit. The luthors evaluated the nature and differences of artifacts in each sequence and parameter. Artifacts induced by both lips were noted in the direction of frequency encoding gradient, and consisted of region of signal loss abutted in one side by survilinear region of bright signal. Geometric distortion of image was marked in the Drake clip, out was minimal in the Yasargil clip under both 2.0T and 0.5T. Artifacts were more pronounced in the gradient echo technique than those of the spin echo technique on both 2.0T and 0.5T. Although there were no differences n the nature of artifacts induced by the Drake clip among each parameter in the spin echo technique under 2.0T, artifacts were slightly more pronounced on T2 weighted image under the 0.5T field, but no differences were found in the nature of artifacts induced by the Yasargil clip in the spin echo technique under, both the 2.0T and 0.5T fields. Marked artifacts were induced through the small area of the Drake clip which were included in the scan plane, but induced artifacts were small when a small area of the Yasargil clip was included in the scan plane. It seemed likely hat artifacts were slightly more pronounced in the 2.0T than the 0.5T field in both clips, but objective evaluation of the difference was difficult, In conclusion, these results can be an essential basis for the interpretation of MR images or patents with metallic inplants.
Aneurysm* ; Artifacts* ; Lip ; Magnetic Resonance Imaging* ; Magnets

No abstract available.
Reference Values*

No abstract available.
Radionuclide Imaging* ; Sodium Pertechnetate Tc 99m* ; Thyroid Gland* ; Thyroid Neoplasms*

No abstract available.
Adenylyl Cyclases* ; Graves Disease* ; Humans ; Thyroid Gland*

No abstract available.
Ligaments* ; Pelvic Organ Prolapse*

In April 2020, a pediatric report of an unusual inflammatory illness associated with coronavirus disease 2019 (COVID-19) led to similar cases in Europe and North America, which was referred to as multisystem inflammatory syndrome in children (MIS-C). Herein, we describe the case of a 12-year-old boy who had a history of polymerase chain reactionconfirmed COVID-19 and developed MIS-C approximately three weeks after an initial diagnosis of COVID-19. High fever with abdominal pain mimicking appendicitis was the initial manifestation of MIS-C, which could have been easily missed if the patient's history of COVID-19 was ignored. Intravenous immunoglobulin was administered twice, 24 hours apart, five days after the onset of MIS-C, and the patient fully recovered without any obvious sequelae. Early recognition by disease awareness and prompt management are the keys to saving the lives of children affected by MIS-C.

We present a case of urachal actinomycosis. Twenty four year-old female patient presented with low abdominal pain and a palpable mass. MRI showed an irregular shaped mass extending from the umbilicus to the dome of the bladder, just beneath the rectus muscle. Exploration revealed a hard fibrotic mass which was adhered tightly with appendix, dome of the bladder, left ovary, fallopian tube and sigmoid colon. The ill-defined fibrotic mass with the adhered organ was removed as en bloc. Actinomycosis was diagnosed from the postoperative specimen. Penicillin G was administered postoperatively. At 1 year followup, she is well without subjective symptom except mild frequency and lymphocele in right pelvis, which was aspirated.
Abdominal Pain ; Actinomycosis* ; Appendix ; Colon, Sigmoid ; Fallopian Tubes ; Female ; Follow-Up Studies ; Humans ; Lymphocele ; Magnetic Resonance Imaging ; Ovary ; Pelvis ; Penicillin G ; Umbilicus ; Urachus ; Urinary Bladder

This study was designed to evaluate the potential application of MRI in differentiating static blood from thrombus, age-related changes of thrombus and the signal differences of the intravascular thrombus in various pulse sequences. External jugular vein was ligated at both upper and lower ends to form a static blood column, and thrombin was injected into the column to cause venous thrombosis in a total of 15 mongrel dogs. The MR images were obtained with T1-and T2-weighted spin echo and gradient echo techniques, immediately after the formation of static blood and after 2 hour, 1 day, 1 week, 2 weeks and 4 weeks of the formation of thrombus at a 2.0T MR unit. The signal intensities of the thrombus and adjacent muscles were compared stubjectively, and the signal intensity ratio was compared objectively by the measurement of the signal intensities using a cursor. The MRI findings were compared with histologic findings. The signal intensities of static blood were hyperintense in all pulse sequences, and those of 2-hour, 1-day and 1-week-old thrombi were hyperintense in all pulse sequences. The number of experimental thrombi which showed isointensity on T1-and T2-weighted image, and hypointensity on gradient echo image increased as thrombi aged. The signal intensities of 2-week-old thrombus were isointense on T1-weighted image, hyperintense on T2-weighted image, and hypointense on gradient echo image, while those of 4-week-old thrombus were isointense on T1-weighted and T2-weighted image, and hypointense on gradient echo image in most experimental thrombi. There was a tendency to decrease in a signal intensity ratio as thrombi aged on T1-weighted, T2-weighted and gradient echo images(P<0.01) Histologically, thrombus was not formed and lumen was filled with many red blood cells(RBCs) in 2-hour-old specimen, but fibrin mesh was visible and RBCs decreased in number in 1-day-old specimen. In 1-week-old specimen, vessel was contracted and lumen was filled with thombus, RBCs, platelets, many fibrins and capillary-like strucrutes. The histologic findings of 2-week-old thrombus were similar to those of 1-week-old one except calcification. In 4-week-old specimen, vessels were contracted and lumen was obliterated with fibrosis and organization of the thrombus. Therefore, it is possible to diagnose thrombus, and to assess sequential changes of MRI findings of thrombus by using all pulse sequences, and these results can be essential bases for the interpretation of MR images of patients with venous thrombosis.
Animals ; Dogs* ; Fibrin ; Fibrosis ; Humans ; Jugular Veins ; Magnetic Resonance Imaging* ; Muscles ; Thrombin ; Thrombosis ; Venous Thrombosis*

PURPOSE: If significantly influenced by chronic otomastoiditis(COM), mastoid pneumatization and the position of the sigmoid sinus affect the operative procedure and postoperative complications in middle ear surgery. We evaluated mastoid pneumatization and sigmoid sinus position, and their relationship in COM, especially its during onset. MATERIALS AND METHODS: Using temporal bone CT and referring to any relevant medical records, we retrospect+tively analyzed 107 cases of COM and 49 cases of normal ear. The total case load comprised an adult group, aged above 16 years [100 cases of COM (M:F=46:54, mean age = 45 years), and 42 cases of normal ear,(M:F=20:22, mean age = 44 years)], and a childhood group, aged less than 16 years [7 cases of COM (M:F=4:3, mean age = 8.4 years), and 7 cases of normal ear (M:F=4:3, mean age = 7 years)]. We determined the thickness of the mastoid bone by measuring the shortest distance between the outer cortex of this bone and the deepest border of the sigmoid sinus; the depth of the sigmoid sinus; and the degree of mastoid pneumatization and sclerosis. Fifty-three patients whose medical history clearly included the onset of otomas-toiditis were divided into a child-onset group and an adult-onset group, and the relationship between the onset of otomastoiditis and the thickness of the mastoid bone was compared between the two groups. RESULTS: The mean axial thickness of the mastoid bone was 9.672 <+/-2.745 mm in COM and 12.430 +/-3.027 mm in normal ear. The difference was statisfically significant (p < 0.0001). The mean depth of the sigmoid sinus was 7.557 +/-1.868 mm in COM and 7.591 +/-2.315 mm in normal ear, with no statistically significant difference. In the childhood group, the mean axial thickness of the mastoid bone was 8.672 +/-2.978 mm in COM and 11.778 +/-3.087 mm in normal ear. This difference was statistically significant (p < 0.05). In the adult group, the corresponding figures were 9.742 +/-2.731 mm in COM and 12.538 +/-3.041 mm in normal ear, a dif-ference which was also statistically significant (p < 0.0001). Among patients with an obvious history of COM, child-onset cases totalled 24 (mean axial thickness of the mastoid bone, 9.2.0 +/-2.158 mm), while there were 29 adult-onset cases (mean axial thickness, 10.08 +/-2.99 mm). This difference in thickness between child-onset and adult-onset COM was statistically significant (p < 0.05). CONCLUSION: In COM, the degree of mastoid pneumatization is proportional to the axial thickness of the mastoid bone, and inversely proportional to the degree of sclerosis, anterior location of the sigmoid sinus and the onset of COM. If the sigmoid sinus is properly located, COM may inhibit mastoid pneumatization.
Adult ; Colon, Sigmoid* ; Ear ; Ear, Middle ; Humans ; Mastoid* ; Medical Records ; Postoperative Complications ; Sclerosis ; Surgical Procedures, Operative ; Temporal Bone

Sinus pericranii is a rare vascular anomaly that's characterized by an extracranial vascular mass with anastomotic connections between the intracranial and extracranial systems via the diploic veins of the skull. Preoperative evaluations for making the diagnosis are important to help prevent unexpected intraoperative bleeding. We report here on a case of surgically treated sinus pericranii in a 20-year-old female following minor head trauma. The clinical manifestations, pathogenesis and managements are discussed, and we also review the relevant literature.
Craniocerebral Trauma ; Female ; Hemorrhage ; Humans ; Sinus Pericranii ; Skull ; Veins ; Young Adult