The added value of postmortem magnetic resonance imaging in cases of hanging compared to postmortem computed tomography and autopsy

The purpose of this study was to evaluate the added value of postmortem magnetic resonance imaging (MRI) compared to postmortem computed tomography (CT) an     

Rathke cleft cysts: CT, MR imaging, and pathologic features

The authors retrospectively reviewed the clinical, computed tomography (CT), and magnetic resonance (MR) imaging findings in seven patients with pathologically proved Rathke cleft cysts. All the cysts were located in the anterior sella turcica or the anterior suprasellar cistern. Five cysts had both intra- and suprasellar components, one was entirely intrasellar, and the other was predominantly suprasellar in location. The size of the cysts ranged from 8 to 20 mm. CT scans demonstrated low-density homogeneous lesions in four cases. On MR images of three of these four cases, the cysts had the same intensity as cerebrospinal fluid on T1- and T2-weighted images, while in the fourth case, the cyst was hyperintense on the T1-weighted images. In the remaining three cases, CT showed slight hyperdensity relative to brain parenchyma, suggestive of contrast enhancement. MR showed signal heterogeneity of these lesions with focal components of diminished signal intensity of T2-weighted images. These same foci appeared iso- to slightly hyperintense on T1-weighted images.     

节细胞神经瘤的影像学表现

目的 探讨节细胞神经瘤的CT和MR表现.方法 回顾性分析18例经手术病理证实的节细胞神经瘤的CT、MR影像学资料,所有患者均接受CT平扫及增强扫描,2例接受MR平扫.结果 节细胞神经瘤好发于中青年,位于后纵隔8例,肾上腺5例,腹膜后4例,颈部1例.均为单发病灶、边界清楚,嵌入式生长可呈多种形态.CT平扫:12例为均匀低密度,平均CT值22～37 HU;6例密度不均,平均CT值13～46 HU,其中2例伴有坏死、囊变.2例见斑点状钙化.增强扫描:肿瘤各期均无强化4例,仅动脉期轻度强化5例,仅静脉期轻度强化2例,静脉期及延迟期呈轻、中度渐进性强化1例,三期呈渐进性强化6例;坏死及囊变部分未见强化.2例肿瘤内见肋间后动脉穿行,1例见腰动脉穿行并见细小分支滋养肿瘤.2例下腔静脉推挤受压移位,1例见颈部大血管被包绕.MR平扫:1例信号均匀,1例信号不均;T1WI表现为低信号,T2 WI呈高信号为主,脂肪抑制(SPIR)及扩散加权成像(DWI)呈高信号.结论 节细胞神经瘤的CT及MR表现具有一定特征性,尤其是CT示肿瘤为均匀低密度、伴有斑点状钙化、肿瘤内血管穿行但未受侵,增强扫描动脉期无明显强化或轻度强化,呈渐进性强化方式,DWI示肿瘤呈高信号时,应考虑节细胞神经瘤的可能.     

Degenerative thalamic hamartoma: CT and MR imaging features

We describe hamartomas of possible thalamic origin. CT revealed marked calcification in the mass lesion, and MR imaging revealed contrast enhancement. Histologically, outgrowth of the glia was observed, but no neoplastic component was confirmed. Immunohistochemical staining was positive for the cell-adhesion factor N-CAM and negative for polysialic acid.     

MR imaging of intracranial cysticercosis: comparison with CT and anatomopathologic features

Eight patients with neurocysticercosis were studied with CT and magnetic resonance (MR) imaging. Two cysts were shown better with MR than with CT. A conspicuous, high-intensity mural nodule containing the scolex allowed specific identification of intraventricular and parenchymal cysticerci. CT evidence of calcification and metrizamide enhancement in the nodule was also noted in one case. Racemose cysts were seen in the cerebellopontine angle and under the anterior septum pellucidum. Fluid in apparently live cysticerci and in racemose cysts had MR signal properties closely paralleling CSF. A thin subependymal or subpial rim of high signal intensity around the intraventricular and one of the racemose cysts was consistent with tissue reaction and aided diagnosis. While MR showed only one of numerous calcifications, it may be more sensitive than CT in the recognition of perifocal edema and of parenchymal and subarachnoid cysts, may replace invasive ventriculography in the diagnosis of intraventricular cysts, and may be useful in determining the viability of cysts and their response to therapy.     

Mediastinal lymphangioma in adults: CT and MR imaging features

Adult mediastinal lymphangiomas are rare lesions the diagnosis of which is difficult based on imaging studies. A retrospective study of CT, MR, and pathologic findings of mediastinal lymphangioma was performed in order to correlate pathological and imaging findings. Nine cases of adult lymphangiomas were identified in the records of our institution over a 12-year period. The CT, MR, and pathologic findings were reviewed. Lesions were classified pathologically as unilocular, cavernous, and intermediate types. Pathologic examination identified six cases of unilocular lesion, two cases of cavernous type, and one intermediate type. The CT features (n = 9) included a smoothly marginated non-enhancing mass of water attenuation (n = 7), a non-enhancing mass of soft tissue attenuation (n = 1), and an enhancing multiseptated mass (n = 1). Lesions were located in the anterior mediastinum (n = 2), right paratracheal (n = 4), subcarinal (n = 1), aortopulmonic window (n = 1) areas, and below the left hilum extending into the posterior mediastinum (n = 1). The MR features (n = 3) were characterized by an enhancing multicystic and multiseptated appearance, evocative of a cavernous type in two cases. The CT appearance of mediastinal thoracic lymphangioma is variable depending on the pathologic type. The most common unilocular type is a non-enhancing thin-walled mass on CT. A less frequent cavernous type can be suggested based on a multiseptated and loculated mass on CT and/or MR examination. Received: 21 June 1999; Revised: 30 September 1999; Accepted: 23 February 2000     

Cervical spine: postmortem assessment of accident injuries--comparison of radiographic, MR imaging, anatomic, and pathologic findings.

PURPOSE: To assess the ability of postmortem radiography and magnetic resonance (MR) imaging to depict occult cervical spine injuries as compared with anatomic and pathologic findings. MATERIALS AND METHODS: The cervical spines of 10 adult accident victims underwent radiography and MR imaging, with T1-weighted, fast spin-echo T2-weighted, and four gradient-echo pulse sequences. The frozen specimens were cut into 3-mm-thick slices (sagittal plane) and photographed, and microfocus radiographs were obtained. Imaging findings were compared with the anatomic and pathologic findings. RESULTS: Eight of the 10 specimens had 28 posttraumatic lesions: three fractures (two missed at the initial MR imaging reading), 10 facet joint capsule lesions with bleeding, five soft-tissue and ligament lesions, eight disk lesions, and two spinal cord lesions. Radiography depicted one lesion (4%). Two partial ruptures of the anterior annulus fibrosus were depicted at only MR imaging. Initially, 11 of 28 lesions were detected on MR images; retrospectively, 17 of 28 lesions were correlated with anatomic findings. CONCLUSION: Soft-tissue and intervertebral disk and ligament injuries account for 89% (25 of 28) of posttraumatic cervical spine lesions detected on postmortem images. Occult lesions, including apophyseal joint injuries, were found in clinically noninjured cervical spines. MR imaging was limited in the depiction of discrete lesions when T1-weighted non-fat-saturated, fast spin-echo T2-weighted, and gradient-echo pulse sequences were used.     

Orbital tumors in children: CT and MR imaging features

The purpose of the article is to review the CT and MR imaging features of orbital tumors in children. Tumors in children are usually different than those in adults. Clinical symptoms are usually non-specific. Clinical examination combined with US may be sufficient for diagnosis and follow-up of benign and superficial lesions. CT and/or MRI are needed for deep or malignant lesions. CT is valuable for osseous and/or calcified lesions. MR is advantageous because of its superior spatial resolution and non-ionizing nature. Malignant tumors correspond to about 20% of lesions and include primary tumors (retinoblastoma, rhabdomyosarcoma) and metastases. Benign pathology is more frequent (80%) with dermoid cyst corresponding to about 50% of orbital masses.     

CT and MR imaging features of pyogenic ventriculitis

BACKGROUND AND PURPOSE: Pyogenic ventriculitis is an uncommon manifestation of severe intracranial infection that might be clinically obscure. We hypothesized that determining characteristic imaging features of pyogenic ventriculitis in patients with appropriate risk factors might improve recognition of this severe infection. METHODS: Review of the medical records from 1990 to 2000 revealed 17 cases (12 men, five women) that satisfied inclusion criteria of abscess (n = 3) and/or positive cultures or increased white cells and protein in ventricular (n = 12) or cisternal (n = 1) cerebrospinal fluid. In one case, the diagnosis of ventriculitis was based on the combination of bacterial growth in lumbar cerebrospinal fluid and follow-up imaging. Staphylococcus species and Enterobacter species were the most common organisms. Two neuroradiologists independently evaluated imaging studies for hydrocephalus, ventricular debris, periventricular attenuation or signal abnormality, ependymal enhancement, and signs of meningitis or abscess. Sixteen studies in 11 patients were performed after the intravenous administration of contrast material. RESULTS: Ventricular debris was detected in 16 (94%) of 17 cases and was irregular in 13 (81%) of 16 cases. Hydrocephalus was present in 13 (76%) of 17 cases. Periventricular hyperintense signal was present in most (seven [78%] of nine) cases with MR imaging and was most conspicuous on fluid-attenuated inversion recovery sequences. Ependymal enhancement was detected in seven (64%) of 11 cases in which contrast material was administered. Signs of meningitis (eg, pial or duraarachnoid signal abnormality or enhancement) were present in 13 (76%) of 17 cases. Three cases had imaging signs of abscess. CONCLUSION: Ventricular debris was the most frequent sign of ventriculitis in this series. An irregular level was characteristic of debris in ventriculitis. Hydrocephalus and ependymal enhancement were less frequent signs. Detection of ventricular debris might facilitate diagnosis of pyogenic ventriculitis, a potentially fatal infection, and thus permit appropriate therapy.     

Novel diagnostic imaging features of facial lupus panniculitis: ultrasound,CT, and MR imaging with histopathology correlate

Lupus panniculitis (LP), also referred to as lupus erythematosus profundus (LEP), is a chronic recurrent inflammation condition of the subcutaneous fat. It occurs in 1 to 3% of patients with systemic lupus erythematosus (SLE) and in 10% of patients with discoid lupus erythematosus (DLE), but can also occur as an entity of its own. Patients with lupus panniculitis usually present with persistent, often tender and painful skin lesions, or subcutaneous nodules, that range from 1 to 5 cm in diameter. The overlying skin may appear erythematous; lesions may become ulcerated, and heal with atrophy, skin depression, dimpling and scaring. Lesions tend to resolve spontaneously and may follow a chronic course of remission and exacerbation that persists for months to years.The imaging features of facial LP are extremely scarce in the literature. We present a case of facial lupus panniculitis and describe the associated characteristic ultrasound, CT, and MR imaging findings along with histopathologic correlation.     

Novel diagnostic imaging features of facial lupus panniculitis: ultrasound,CT, and MR imaging with histopathology correlate

Lupus panniculitis (LP), also referred to as lupus erythematosus profundus (LEP), is a chronic recurrent inflammation condition of the subcutaneous fat. It occurs in 1 to 3% of patients with systemic lupus erythematosus (SLE) and in 10% of patients with discoid lupus erythematosus (DLE), but can also occur as an entity of its own. Patients with lupus panniculitis usually present with persistent, often tender and painful skin lesions, or subcutaneous nodules, that range from 1 to 5 cm in diameter. The overlying skin may appear erythematous; lesions may become ulcerated, and heal with atrophy, skin depression, dimpling and scaring. Lesions tend to resolve spontaneously and may follow a chronic course of remission and exacerbation that persists for months to years.The imaging features of facial LP are extremely scarce in the literature. We present a case of facial lupus panniculitis and describe the associated characteristic ultrasound, CT, and MR imaging findings along with histopathologic correlation.     

Melorheostosis involving the cervical and upper thoracic spine: radiographic, CT, and MR imaging findings

Melorheostosis, an uncommon mesenchymal dysplasia, rarely affects the axial skeleton. We describe the imaging findings of melorheostosis involving the cervical and upper thoracic spine. Radiographs and CT showed unilateral well-marginated undulating zones of cortical hyperostosis involving multiple vertebrae that were contiguous with a coalescent ossified right paravertebral mass. MR imaging showed zones of signal intensity void on all pulse sequences without contrast enhancement. Conservative management was elected because of lack of interval clinical and imaging changes for 8 years.     

Intraarticular osteoid osteoma: sonographic findings in three patients with radiographic, CT, and MR imaging correlation.

OBJECTIVE: Intraarticular osteoid osteoma often has subtle radiographic findings and nonspecific clinical features; further diagnostic workup of unexplained joint pain may involve musculoskeletal sonography. We describe the sonographic features of intraarticular osteoid osteoma in three consecutive patients with radiographic, CT, and MR imaging correlation. CONCLUSION: The sonographic findings of painful cortical irregularity and focal synovitis should raise the possibility of intraarticular osteoid osteoma, prompting the search for characteristic findings on correlative imaging studies.     

Hepatic and extrahepatic alveolar echinococcosis: CT and MR imaging features

To illustrate the CT and MR imaging features of alveolar echinococcosis, a rare disease that is endemic in the northeast of France. Hepatic and extrahepatic manifestations are presented. Fibrous and necrotic features are demonstrated on MR. Calcifications are demonstrated on CT. Accurate imaging diagnosis will exclude tumors (cholangiocarcinoma, cystadenoma, fibrous metastases) and avoid unnecessary biopsy.     

Intraabdominal panniculitis: clinical, radiographic, and CT features

Intraabdominal panniculitis, also known as lipodystrophy, is an inflammatory condition of adipose tissue that may result in development of large masses containing necrotic fat (nodular intraabdominal panniculitis). Symptoms are secondary to inflammation or mass effect on adjacent organs. Barium studies may show nonspecific inflammatory changes and displacement of bowel loops. Computed tomography (CT) demonstrates inhomogeneous masses containing fat and soft tissue density. The diagnosis of intraabdominal panniculitis has seldom been made prospectively. However, the CT findings are characteristic and can aid in the evaluation and management of patients with this disease.     

CT and MR imaging features of adnexal torsion.

In adnexal torsion, the ovary, ipsilateral fallopian tube, or both twist with the vascular pedicle, resulting in vascular compromise. Unrelieved torsion is likely to cause hemorrhagic infarction as the degree of arterial occlusion increases. Therefore, early diagnosis is important to preserve the affected ovary. Adnexal torsion commonly accompanies an ipsilateral ovarian neoplasm or cyst but can also occur in normal ovaries, usually in children. Although ultrasonography is typically the initial emergent examination, computed tomography (CT) and magnetic resonance (MR) imaging may also be useful diagnostic tools. Common CT and MR imaging features of adnexal torsion include fallopian tube thickening, smooth wall thickening of the twisted adnexal cystic mass, ascites, and uterine deviation to the twisted side. Uncommon imaging findings in adnexal torsion that are specific to hemorrhagic infarction include hemorrhage in the thickened fallopian tube, hemorrhage within the twisted ovarian mass, and hemoperitoneum. Additional imaging findings that can suggest hemorrhagic infarction include eccentric smooth wall thickening exceeding 10 mm in a cystic ovarian mass converging on the thickened fallopian tube and lack of contrast enhancement of the internal solid component or thickened wall of the twisted ovarian mass. Early diagnosis can help prevent irreversible structural damage and may allow conservative, ovary-sparing treatment.     

Lumbar root compression in the lateral recess: MR imaging,conventional myelography,and CT myelography comparison with surgical confirmation

BACKGROUND AND PURPOSE: Previous authors have shown that conventional myelography is superior to plain CT in the assessment of root compression in the lateral recess, but this question has never been evaluated with respect to MR imaging of the lumbar level. Our purpose was to assess the accuracy of MR imaging, conventional myelography, and postmyelography CT (CT myelography) of the lumbar level in identifying degenerative lateral recess root compression with surgical confirmation. METHODS: MR imaging, conventional myelography, and CT myelography of the lumbar level were assessed in the imaging of 58 lateral recesses at 38 lumbar levels in 26 patients who underwent surgery for radiculopathy with degenerative lateral recess abnormality. Each lateral recess was graded as normal, small without root compression, small with root compression, or severe root compression. RESULTS: MR imaging underestimated root compression in 28% to 29% of the cases in which root impingement was surgically confirmed. Conventional myelography underestimated root compression in only 5% to 7% of the cases and correctly predicted impingement in 93% to 95%. CT myelography underestimated root compression in 38% of the surgically confirmed cases. CONCLUSION: MR imaging significantly underestimated root compression caused by degenerative changes in the lateral recess. Although MR imaging is a superb study when used in the search for degenerative disk disease and disk protrusion, conventional myelography is a crucial supplemental study that is necessary to confirm degenerative root impingement in the lateral recess as the cause of radiculopathy.