Acute spinal epidural and subdural hematomas

Acute spinal epidural and subdural hematomas are rare entities. The clinical presentation is similar in both cases. MR imaging is the most appropriate imaging technique. On axial images, epidural hematoma has a biconvex shape. It is separated from the spinal cord by the hypointense dura on T2-weighted images. Conversely, subdural hematoma has a crescentic shape on axial images and is located medially to the dura. In the latter case, the epidural fat is not involved. There is no surgical indication for patients with early and rapid regressive symptoms. In other cases the surgical treatment consists of hematoma evacuation.     

MRI findings in spinal subdural and epidural hematomas

BACKGROUND: Spinal hematomas are rare entities that can be the cause of an acute spinal cord compression syndrome. Therefore, an early diagnosis is of great importance. PATIENTS AND METHODS: From 2001 to 2005 seven patients with intense back pain and/or acute progressive neurological deficit were studied via 1.5 T MRI (in axial and sagittal T1- and T2-weighted sequences). Follow-up MRI was obtained in six patients. RESULTS: Four patients showed the MRI features of a hyperacute spinal hematoma (two spinal subdural hematoma [SSH] and two spinal epidural hematoma [SEH]), isointense to the spinal cord on T1- and hyperintense on T2-weighted sequences. One patient had an early subacute SEH manifest as heterogeneous signal intensity with areas of high signal intensity on T1- and T2-weighted images. Another patient had a late subacute SSH with high signal intensity on T1- and T2-weighted sequences. The final patient had a SEH in the late chronic phase being hypointense on T1- and T2-weighted sequences. DISCUSSION: MRI is valuable in diagnosing the presence, location and extent of spinal hematomas. Hyperacute spinal hematoma and the differentiation between SSH and SEH are particular diagnostic challenges. In addition, MRI is an important tool in the follow-up in patients with conservative treatment.     

Acute isodense subdural hematomas: a problem in anemic patients

Although numerous articles have appeared in the literature on chronic isodense subdural hematomas, acute isodense subdural hematomas have received little attention. An experimental model was developed that demonstrated that blood with reduced hemoglobin concentration, 8-10 g/dl, is isodense with the brain. Two anemic patients with acute isodense subdural hematomas are reported.     

Acute spinal subdural hematoma: MR and CT findings with pathologic correlates.

PURPOSETo determine the MR and CT findings that characterize acute spinal subdural hematoma (ASSH).METHODSThe MR, CT, and clinical findings in three patients with surgically proved ASSH were reviewed and also correlated with the postmortem MR, CT, and cryomicrotome findings in three other patients, two with ASSH and one with an acute spinal epidural hematoma.RESULTSImaging findings in ASSH included: (a) hyperdense lesions on plain CT within the dural sac, distinct from the adjacent low-density epidural fat and silhouetted against the lower-density spinal cord and cauda equina, which it compressed; (b) lack of direct continuity with the adjacent osseous structures; (c) clumping, loculation, and streaking of blood within the dural sac on both MR and Ct; and (d) an inhomogeneous and variable signal intensity to the ASSH on all MR pulse sequences, but, nevertheless, a striking low signal intensity on T2-weighted spin-echo or T2-weighted gradient-echo to a major part of the ASSH because of deoxyhemoglobin. Plain CT was most helpful in compartmentalizing the hematoma.CONCLUSIONWhen MR and plain CT are obtained as complementary studies, they provide characteristic findings that allow the prompt diagnosis of ASSH.     

Chronic subdural hematomas

Summary Surgery was undertaken on 32 chronic subdural hematomas in a series of 28 patients who had preoperatively undergone delayed contrast-enhanced computed tomography (DCECT). Timedensity curves on DCECT and iodine concentrations of subdural specimens revealed that chronic subdural hematomas, regardless of density, were significantly enhanced by the entrance of intravascular contrast medium into the interior of hematomas. The ingress of intravascular contrast medium into the interior of the hematomas was chemically proven and might result from a complex transcapillary shift.     

Isodense subdural haematomas on CT: MRI findings

Summary MRI findings are described in two patients with subdural haematomas isodense on CT. In one patient, admitted 6 weeks after trauma, a chronic subdural haematoma showed extreme hypointensity on T2-weighted images, suggesting acute trauma, and therefore acute rebleeding. In the second patient with severe anaemia, an acute subdural haematoma was hyperintense on T2-weighted images, suggesting chronic trauma; this may be explained by the low haematocrit and a possible mixture of blood with cerebrospinal fluid. The MRI features of subdural haematomas and hygromas have to be kept in mind, in order not to misjudge the age of the haematoma.     

Age determination of subdural hematomas with CT and MRI: A systematic review

Objectives

To systematically review the literature on dating subdural hematomas (SDHs) on CT and MRI scans.

Methods

We performed a systematic review in MEDLINE, EMBASE and Cochrane to search for articles that described the appearance of SDHs on CT or MRI in relation to time between trauma and scanning. Two researchers independently screened the articles, assessed methodological quality and performed data extraction. Medians with interquartile ranges were calculated. Differences were tested with a Mann–Whitney U or Kruskal–Wallis H test.

Results

We included 22 studies describing 973 SDHs on CT and 4 studies describing 83 SDHs on MRI. Data from 17 studies (413 SDHs) could be pooled. There were significant differences between time intervals for the different densities on CT (p < 0.001). Time interval differed significantly between children and adults for iso- and hypodensity (p = 0.000) and hyperdensity (p = 0.046). Time interval did not differ significantly between abused and non-abused children. On MRI, time intervals for different signal intensities on T1 and T2 did not differ significantly (p = 0.108 and p = 0.194, respectively).

Conclusions

Most time intervals of the different appearances of SDHs on CT and MRI are broad and overlapping. Therefore CT or MRI findings cannot be used to accurately date SDHs.     

非典型肺转移瘤的CT表现

目的:分析非典型肺转移瘤的CT表现形式,以提高对本病的诊断准确性。方法:回顾性分析42例经临床、手术及病理证实的非典型肺转移瘤的CT表现,探讨其与原发肿瘤的关系。结果:本组病例显示非典型肺转移瘤CT表现:空洞型转移12例,钙化型转移9例,肺炎型转移8例,孤立型转移6例,转移瘤内支气管充气征5例,自发性气胸2例。结论:肺转移瘤可以表现多种不典型征象,熟悉这些征象对临床诊断和治疗有重要意义。     

False positive appearance of subarachnoid hemorrhage on CT with bilateral subdural hematomas

We describe a patient with bilateral traumatic subdural hematomas in whom CT findings of hyperattenuation in the basal cisterns and subarachnoid spaces falsely suggested superimposed acute subarachnoid hemorrhage.     

Acute bowel ischemia: CT findings

Acute bowel ischemia represents one of the most dramatic abdominal emergencies and, despite the fact it is more and more frequently observed in clinical practice, its mortality rate remains very high. In recent years Computed Tomography (CT) has proved to be a valid diagnostic tool in the evaluation of patients with acute abdominal syndrome and in the visualization of early signs of bowel ischemia. This paper reviews the aetiological and pathophysiological aspects as well as a broad spectrum of CT findings of this clinical condition.     

CT findings of atypical forms of phakomatosis

Summary Three cases with unusual manifestations of phakomatosis are reported. The first two had clinical symptoms of neurofibromatosis but CT disclosed nodular subependymal calcifications as in tuberous sclerosis. The third one presented with cerebral calcifications as found in both tuberous sclerosis and Sturge-Weber syndrome, though he had no clinical symptoms of phakomatosis.     

大脑镰、小脑幕硬膜下血肿的CT诊断价值

大脑镰、小脑幕硬膜下血肿较少见,常与蛛网膜下腔出血、脑膜钙化不易鉴别而漏诊或误诊。本文收集36例大脑镰、小脑幕硬膜下血肿的CT资料结合文献分析如下。1资料与方法36例大脑镰、小脑幕硬膜下血肿中,男25例,女9例,年龄27~67岁,平均48岁。车祸伤31例、建筑工地坠落伤3例、击打