Imaging of Melorheostosis: Emphasis on MR Imaging Findings

PURPOSE: To evaluate the usefulness of various radiographic imaging modalities in the diagnosis and characterization of melorheostosis. MATERIALS AND METHODS: We retrospectively evaluated the plain film (n=8), computed tomographic (CT) imaging (n=5) and magnetic resonance (MR) imaging (n=5) findings of eight patients with melorheostosis diagnosed by bone biopsy (n=4) and characteristic radiographic findings (n=8). MR images were obtained with a 1.5-T scanner focused on the region of maximal radiographic abnormality. Pulse sequences include T1-weighted SE, T2-weighted fast SE (n=5) and postcontrast imaging (n=4). In order to define subtle enhancement of the lesions, subtraction MR images were obtained in one case. Imaging findings were analyzed with particular emphasis on the distribution of lesions along the sclerotome, differential radiographic findings between diaphyseal and metaepiphyseal lesions of the long bones, as seen on plain radiographs, and the density and signal characteristics of hyperostotic, lesions, as seen on CT and MR images. RESULTS: Characteristic distribution along the sclerotome was identified in five of eight cases mainly along C6 and 7 (n=2) and L3, 4 and 5 (n=3) sclerotomes. In diaphyseal melorherostosis (8/8), a characteristic finding, i.e., a wax flowing down from the candle, was identified on plain radiographs. In all three patients with metaepiphyseal melorheostosis (3/8), multiple round or oval hyperostotic lesions were seen in the epiphysis and metaphysis of the long bones. On CT, the marrow cavity was partly obliterated by hyperostotic lesions in all five patients with endosteal hyperostosis. Among these, central ground glass opacity with a sclerotic rim was seen in three patients. Periosteal hyperostosis was seen in two of five cases, being visualized as irregular excrescences in the periosteal region and surrounding soft tissue. Individual hyperostosis was visualized as hypointense on T1-weighted images and as a hyperintense center with a surrounding hypointense rim on T2-weighted images (5/5). On postcontrast images, central enhancement was noted in all four cases. In one of these, in which the degree of central enhancement was subtle, subtraction images (postcontrast SE- precontrast SE) also revealed a central signal increment. Central enhancement corresponded to the hyperintense center seen on T2-weighted images (4/4) and the ground-glass opacity seen on CT (2/2). CONCLUSION: Radiographic imaging plays a crucial role in the diagnosis of melorheostosis. The future role of gadolinium-enhanced MR imaging in the characterization of the lesion may be important though further evaluation and pathologic correlation is required.

MR Imaging of Tibial Plateau Fractures: Evaluation of Fracture Types and Associated Soft Tissue Injuries

PURPOSE: To evaluate the usefulness of magnetic resonance imaging (MRI) for assessing fracture types and soft tissue injuries associated with tibial plateau fractures. MATERIALS AND METHODS: MRI was performed in 38 patients with tibial plateau fractures, each of which was classified according to the Schatzker system. We evaluated MR images and assessed the prevalence of each fracture type and accompanying soft tissue injuries. We also assessed whether ligamentous injury correlated with the extent of articular depression, splitting, and comminution. In 24 patients, diagnosis was based on MRI and operative or arthroscopic findings, and in 14 patients, on MRI alone. RESULTS: The totals of fracture types I, II, III, IV, V and VI were 4 (11 %), 15 (39 %), 6 (16 %), 4 (11 %), 4 (11%), and 5 cases (13 %), respectively. In 30 cases (79 %), there were associated ligamentous or meniscal injuries. Medial collateral ligaments and lateral menisci were injured in 17 (45 %) and 14 cases (37 %), respectively. Type II and IV fracture patterns were associated with soft tissue injuries in 14 of 15 cases (93 %) and 4 of 4 cases(100 %), respectively. As the extent of articular depression increased and the extent of bony comminution decreased, there was an increased prevalence of accompanying ligamentous injuries. CONCLUSION: In tibial plateau fractures, MR imaging is a useful diagnostic modality for the evaluation of both fracture type and accompanying ligamentous or meniscal injuries.

A Relationship Between Amount of Joint Effusion, Disk Displacement and Presence of Pain in theTemporomandibular Joint: MR Imaging

PURPOSE: To correlate MR findings of amount of temporomandibular joint effusion with joint pain and disk displacement. MATERIALS AND METHODS: In 57 patients, 114 temporomandibular joints with symptoms of disorder(presence of clinical pain) were imaged. Closed and open mouth sagittal spin echo (SE) T1-weighted images (WI) and fast spin echo (FSE) T2-WI were obtained. We classified the amount of joint effusion into grades. Joint effusion was classified as either Grade I, II or III, as follours : in sagittal FSE T2-WI, a long diameter of joint effusion shorter than 1/3 of the diameter of the convex margin of temporal eminence was grade I; longer than 2/3 was grade III; between grade I and III was grade II. Disk displacement was classified as either with or without reduction in the open mouth position. These findings were correlated with one another and statistically analyzed. RESULTS: In 29 cases with joint pain (37%) and in 34 cases without pain (63%) there was no evidence of joint effusion; there were, however, more grade I joint effusion cases with pain (14 ; 60.9%) than without pain (9 : 39.1%). Cases of joint pain increased in proportion to grade of joint effusion, which was statistically significant (p<0.05). In joints without disk displacement, the largest grouping was that which showed no effusion (39 ; 72.2%) ; no joints showed grade III effusion. Cases of joint effusion decreased in proportion to grade of effusion. In joints with disk displacement, cases of joint effusion tended to increase in proportion to the grade of effusion. CONCLUSION: MR findings of amount of temporomandibular joint effusion correlate with joint pain and anterior disk displacement.

Adrenal Myelolipoma Confirmed by Fine Aspiration Biopsy / 대한내분비학회지

Adrenal myelolipomas are rare, benign tumors cornposed of mature fat and bone marrow elements. Most are small, asymptomatic tumors found incidentally at postmortem examination, Fine needle aspiration biopsy can be used to confirm the diagnosis and avoid an unnecessary operation. We report a case of adrenal myelolipoma confirmed by fine needle aspiration biopsy. A 77-year-old woman with complaining of upper abdominal pain for 2 days was found to have an adrenal mass. She took dexamethasone frequently for 3 years due to multiple arthralgia. Ultrasono-graphy showed a 6cm-sized, suprarenal mass and a stone in the gall bladder with thickened wall. Computed tomography and magnetic resonance imaging scan also presented a suprarenal mass. Endocrinologic results were within normal limits. Adrenal myelolipoma was confirmed by computed tomography-guided fine needle aspiration biopsy without surgery.

Brodie's Abscess in Pediatric Patients: MR Imaging Findings

PURPOSE: To determine the characteristic MR imaging findings of Brodie's abscess in pediatric patients. MATERIALS AND METHODS: We retrospectively reviewed 17 pediatric patients with surgically-proven or clinically and radiologically diagnosed Brodie's abscess who had undergone T1- and T2-weighted spin-echo sequences, T2-weighted fast spin-echo sequence and gadolinum enhanced MR imaging. The MR imaging findings were analysed and classified according to the signal characteristics of the abscess and srrounding bone marrow. RESULTS: The MR imaging findings of Brodie's abscess could be classified as one of three types, as follows : Type I (10/17) was seen as a target appearance with four layers ; i.e. a center with low signal intensity on T1-weighted images and high signal intensity on T2-weighted images; an inner rim of high signal intensity, as compared with muscle on both T1- and T2-weighted images with intense contrast enhancement; an outer rim of low signal intensity on both T1- and T2-weighted images, and a peripheral halo of low signal intensity on T1-weighted images and variable signal intensity on T2-weighted images. In type II (4/17), there was no distinction between the center and the inner rim on T1-weighted images, but a clear distinction on contrast enhanced images by intense enhancement of the inner rim. In type III (3/17), there was no distinction between the center and the inner rim on either T1-weighted or contrast enhanced images, due to diffuse enhancement of the lesions. Additional findings of Brodie's abscess include epiphyseal plate violation (8/17), linear or tubular sinus tracts (7/17), inflammatory reaction or edema of surrounding soft tissue (7/17), periosteal reaction (1/17), and pyogenic arthritis (1/17). CONCLUSION: MR imaging is a useful diagnostic tool for the characterization and determination of the extent of Brodie's abscess. Contrast enhanced MR imaging is particularly valuable for the evaluation of type II lesions.

Abnormal Uterine Bleeding Due to Vascular Abnormality Caused by D&E : Doppler Sonography for Diagnosis and Transcatheter Arterial Embolization for Treatment

PURPOSE: We attempted to evaluate the usefulness of Doppler sonography in the diagnosis of uterine vascular abnormality caused by previous D&E, and to report that transarterial embolization is an exceelent treatment modality. MATERIALS & METHODS: We analyzed gray-scale US, color/duplex Doppler US and angiographic findings inseven patients with radiologically proven uterine vascular abnormality. Two of the seven cases were pseudoaneurysms and five of the seven cases were AVMs. In one of the AVMs, two small pseudoaneurysms were combined. In all cases, transarterial embolizations using 3mm coil or/and gelfoam particles were performed. Follow-up US studies, including color Doppler US, were performed. RESULTS: On color/duplex Doppler sonography, two cases of pseudoaneurysm showed blood pools with turbulent arterial flow, and five cases of AVM showed asymmetrically increased vascularity, with variable high velocities composed of the pulsatie arterial flow, with ahigh diastoic component. On angiography, the former showed pseudoaneurysmal sacs, and the latter densely opacified vascular tangles. No more abnormal uterine bleeding was shown, following transarterial embolization in all cases. CONCLUSION: Color/duplex Doppler sonography was valuable in the diagnosis or treatment of abnormal uterine bleeding caused by uterine vascular abnormality such as acquired AVM or pseudoaneurysm.

Abdominal Ultrasonographic Findings of Salmonellosis

PURPOSE: We evaluated the abdominal uttrasonographic findings of Salmonellosis. MATERIALS AND METHODS: This study included 64 patients who were confirmed as salmonellosis by blood culture. We retrospectively analyzed the abdominal ultrasonographic findings with particular attention to enlarged mesenteric lymph nodes(mesenteric lymphadenitis), thickening of bowel wall, especially terminal ileum and cecum(ileocecitis), hepatosplenomegaly, ascites, gallbladder wall thickening, and enlarged lymph nodes in porta hepatis. RESULTS: The 64 cases were observed as mesenteric lymph node enlargement(44 cases), wall thickening of the terminal ileum and cecum(36 cases), hepatomegaly and/or splenomegaly(42 cases), minimal ascites(8 cases), gallbladder wall thickening(6 cases), and enlarged lymph nodes in porta hepatis(4 cases). No abnormal finding was seen in 10 patients. CONCLUSION: The mesenteric lymph node enlargement, wall thickening of the terminal ileum and cecum, hepatomegaly and/or splenomegaly, minimal ascites, gallbladder wall thickening, and enlarged lymph nodes in porta hepatis are suggestive findings of salmonellosis on abdominal ultrasonography in patients with fever and acute abdomen.

Recurrent Intracranial Meningioma with Malignant Change and Extracranial Bone Metastasis: A Case Report

In general, meningiomas are slowly growing benign neoplasms originating from specialized meningothelial cells in arachnoid granulation, but have a tendency to be locally invasive and recurrent. Meningiomas very rarely metastasize outside the nervous system, occurring in less than 0.1%. We report the CT and MR findings of a case of a solitary benign syncytial meningioma showing recurrent multiple tumors and malignant progression with eventual bone metastasis to rib after six surgical extirpations during six years.