Dural carcinomatosis: MR demonstration

A case of pachymeningeal carcinomatosis is presented in which CT evaluation revealed an extraaxial, heterogeneous density over the left cerebral convexity. The finding was believed to be consistent with subdural hematoma, empyema, or meningeal thickening. Magnetic resonance evaluation demonstrated a similar crescentic lesion that was of intermediate signal intensity on both T1- and T2-weighted images. This was thought to be uncharacteristic of either subdural hematoma or empyema. The T2-weighted image showed CSF interposed between the cerebrum and the lesion, limiting the abnormality to the dura or subdural space.     

MR Imaging of Shaken Baby Syndrome Manifested as Chronic Subdural Hematoma

Shaken baby syndrome (SBS) is a form of child abuse that can cause significant head injuries, of which subdural hematoma (SDH) is the most common manifestation. We report the MRI findings of chronic SDH in three cases of SBS, involving two-, three- and eight-month-old babies. The SDH signal was mostly low on T1-weighted images and high on T2-weighted images, suggesting chronic SDH. In chronic SDH, a focal high signal on T1-weighted images was also noted, suggesting rebleeding. Contrast-enhanced MRI revealed diffuse dural enhancement.     

Diffusion-weighted MRI of subdural and epidural empyemas

We reviewed diffusion-weighted images (DWI) from eight patients with subdural and four with epidural empyemas to assess the possibility of differentiating between these lesions by DWI. The signal intensities of the empyemas on DWI, and maps of the apparent diffusion coefficient (ADC) were analysed in seven patients. In seven of the eight patients with subdural empyema, the lesions appeared as areas of high signal. The ADC maps confirmed that these areas were the result of restricted diffusion. (In the remaining patient, the lesion showed a mixture of high and low signal.) The epidural empyemas contained areas of low signal in all four patients; part of the empyema was isointense or gave high signal in two. DWI may be an adjunct to conventional sequences for differentiating between subdural and epidural empyemas.     

Chest sonography. Differentiation of pulmonary consolidation from pleural disease

Ultrasonography was used to evaluate 53 patients with equivocal juxta-diaphragmatic and/or lateral densities in chest radiographs. An air bronchogram, fluid bronchogram, and scattered echogenic foci due to residual air in the consolidated lung parenchyma were used as US criteria of pulmonary parenchymal consolidation. One or more of these signs were observed in 39 patients with a clinical or bacteriologic diagnosis of pneumonia. The US air bronchogram was seen in 32 of the 39 patients (82%), the fluid bronchogram in 37 patients (94%) and the scattered echogenic foci in 30 (77%). In 14 patients, pleural effusion was diagnosed sonographically and verified by aspiration of fluid. The final diagnoses in these cases were pulmonary tuberculosis in 11 patients, staphylococcal empyema in 2, and tuberculous empyema in one patient. It is concluded that US criteria provide a useful differentiation of pulmonary parenchymal consolidation from pleural effusion.     

The predictive value of computed tomography and Haemophilus influenzae capsular antigen in subdural fluid collections

A study was made of 52 patients with Haemophilus influenzae type B meningitis complicated by subdural collections of fluid to determine which of these collections were sterile (effusions) and which infected (empyema). This differentiation is important for the treatment which differs in the two conditions. Cranial computed tomography (CT) alone was not as reliable as the combination of CT associated with detection of Haemophilus influenzae capsular antigen, in accurately predicting if a subdural fluid collection was infected, or had a high probability of becoming infected.     

Focal angiographic abnormalities with subdural empyema

Summary Thirteen patients with subdural empyema underwent arteriography preoperatively and three were restudied postoperatively. Arterial vascular changes were found in nine cases and consisted of localized or diffuse arterial irregularities. In two cases the arterial changes resolved with effective therapy. These arterial changes are similar in appearance and response to therapy to those noted with meningitis; however, in this series they were shown to have occurred in seven cases with subdural empyema but without associated meningitis. Therefore, subdural empyema alone may cause localized or diffuse arterial irregularities.     

Subdural empyema in adult with recent SARS-CoV-2 positivity case report

Intracranial abscess, including subdural empyema, is a rare central nervous system infectious disease and diagnosis is often delayed due to patient presentation with non-specific neurologic findings. Here we report a 65-year-old male with a recent past medical history of SARS-CoV-2 infection who presented with three weeks of escalating headache in whom MRI imaging revealed a subdural empyema. He subsequently underwent two craniectomies, which resulted in eradication of the abscess and clinical improvement. This report highlights a potential link between SARS-CoV-2 infection and this patient''s development of subdural empyema, which has not been documented elsewhere in the literature.     

Strangulation in child abuse: CT diagnosis

The central nervous system is commonly affected in child abuse. Between April 1985 and July 1986 three infants were identified in whom the primary mode of injury had been strangulation. In each case computed tomography (CT) demonstrated a large cerebral infarction confined to vascular territories associated with small subdural hematomas. There was no history or visible evidence of significant head trauma. Autopsy of one infant confirmed the presence of a hemispheric infarct, thin subdural hematoma, and an area of subintimal hemorrhage in the carotid artery ipsilateral to the infarct. The remaining two patients survived with residual hemiparesis. CT findings of a large cerebral infarction with an associated subdural hematoma in an infant without a history of a significant trauma should suggest the possibility of child abuse and may be the primary manifestation of abuse in some patients.     

Diffusion-weighted MR imaging of subdural empyemas in children

BACKGROUND AND PURPOSE: Subdural empyema (SDE), an infection of the subdural space, occurs most often in pediatric patients as a complication of meningitis, sinusitis, or otitis media. Diffusion-weighted imaging (DWI) has been used in the past to investigate intracerebral infections. The purpose of this study was to determine the signal intensity characteristics of SDE on DWIs as well as the corresponding apparent diffusion coefficient (ADC) maps. METHODS: MR studies of 10 patients with SDEs were retrospectively reviewed. Included were routine sequences and DWI, which consisted of an axial single-shot echo-planar spin-echo sequence (TR/TE, 4000/110) with b values of 0, 500, and 1000 s/mm(2). Signal-intensity characteristics on routine MR images and DWIs were evaluated. In seven patients, ADC values of the lesions were calculated by using two b values. Follow-up imaging study was performed in seven patients. RESULTS: In nine patients, the empyema was hyperintense on DWIs. In the remaining patient, the empyema showed mixed hyperintensity and hypointensity. ADC values were lower than those of normal cortical gray matter and much lower than those of reactive subdural effusions. In all seven patients with persistent clinical signs of infection, the empyemas were hyperintense on follow-up DWIs. CONCLUSION: SDE had high signal intensity on DWIs and low signal intensity on ADC maps, with an ADC value lower than that of the normal cortical gray matter. Diffusion MR imaging can be valuable in distinguishing SDE from effusion and in the follow-up of subdural collections.     

Cranial epidural empyema with osteomyelitis caused by actinomyces, CT, and MRI appearance

Actinomycosis is an uncommon cause of intracranial infection. Epidural empyema represents about 6% of CNS actinomycotic lesions. A case of an epidural empyema with parietal bone osteomyelitis caused by Actinomyces israelii is presented. Relevant neuroimaging features were bone erosions and a multiloculated collection with annular contrast enhancing on CT. Postoperative MRI revealed extensive involvement of the neighbor dura, falx, and subdural space. MRI was crucial to follow-up the response to antibiotic treatment.     

Diagnosis of extracerebral fluid collections by computed tomography.

The computed tomography scans of 90 patients with extracerebral fluid collections were reviewed. Epidural hematomas, acute, subacute, and chronic subdural hematomas, convexity subarachnoid hemorrhages, subdural hygromas, and one epidural empyema were seen. The CT findings were analyzed and correlated with the time elapsed since injury (when known) and the results of radionuclide scans (when available). The overall accuracy of CT in detecting extracerebral fluid was 90% with no acute hemorrhages missed. In subacute and chronic subdural collections, six CT scans were false negative in whole or in part. Three false positive interpretations were made and are discussed.     

Sonography of intracranial infection in infants and children

Summary Congenital and acquired infections of the central nervous system (CNS) pose a significant threat to the developing brain, even in the face of appropriate medical treatment. During the past five years, a number of reports have described the ultrasound features of intracranial infection, including echogenic sulci, extra-axial fluid collections, ventricular enlargement, calcifications, abnormal parenchymal echogenicity, abscess formation, cystic degeneration of the brain parenchyma, intraventricular echogenicity, ventricular septations and irregularity and prominence of the ventricular walls. These features permit ultrasound diagnosis of intracranial infection and help to guide decisions affecting patient management.     

Supratentorial arachnoid cyst and associated subdural hematoma: neuroradiologic studies

CT and MR images of 8 patients with supratentorial arachnoid cyst complicated by subdural hematoma were studied and compared with those of 8 patients who developed nontraumatic subdural hematoma without arachnoid cyst. Of the 8 patients with supratentorial arachnoid cyst, CT and MR disclosed temporal bulging and/or thinning of the temporal squama in all 6 patients with middle fossa arachnoid cysts, and the thinning of the calvaria was evident in another patient with a convexity cyst. Calvarial thinning at the site corresponding to interhemispheric arachnoid cyst was clearly depicted on coronal MR images. In contrast, none of the 8 young patients with nontraumatic subdural hematoma without arachnoid cyst had abnormal calvaria. Temporal bulging and thinning of the overlying calvaria were identified as diagnostic CT and MR features of arachnoid cyst with complicating intracystic and subdural hemorrhage. Radiologists should be aware of this association and should evaluate the bony structure carefully. Correspondence to: M. Ochi     

改良大骨瓣开颅个体化外减压术治疗重型颅脑损伤伴急性硬膜下血肿

目的 分析改良大骨瓣开颅个体化减压术对重型颅脑损伤伴急性硬膜下血肿治疗效果和手术方法. 方法 回顾性分析2007年7月-2010年6月采用改良大骨瓣开颅个体化减压术治疗重型颅脑损伤伴急性硬膜下血肿患者81例(治疗组)与2004年7月-2007年6月采用标准外伤大骨瓣减压治疗同样的患者65例(对照组)的治疗效果. 结果 伤后6个月GOS评估法判定其疗效:治疗组良好(5分)21例,中残(4分)19例,重残(3分)24例,植物生存(2分)5例,死亡(1分)12例(P＜0.01),预后较好(良好/中残)占49%(P＜0.05),预后较差或差(重残/植物生存/死亡)占51%;对照组良好(5分)12例,中残(4分)9例,重残(3分)22例,植物生存(2分)3例,死亡(1分)19例,预后较好占32%,预后较差占68%.治疗组并发术后颅内血肿、硬膜下积液明显少于对照组(P＜0.05).结论 改良大骨瓣开颅个体化减压术治疗重型颅脑损伤伴急性硬膜下血肿有较好疗效,能有效降低大骨瓣减压术后并发症的发生.     

Differential diagnosis of subdural effusions

Although x-ray computerized tomography facilitates the diagnosis of intracranial disorders, differentiation of the lesions like extracerebral effusions is often unsatisfactory. Epidural and acute subdural haematoma shown as hyperdensity in CT requires an emergency neurosurgical operation, so that differentiation of these hyperdense effusions may not be required. But the discrimination of the effusions shown as hypodensity in CT (chronic subdural haematoma, subdural hygroma, subdural empyema as well as arachnoid cysts) is urgent because of the different treatment of these effusions. The clinical differentiation is hampered by unspecific neurologic symptoms and the lack of adequate laboratory tests. Some aspects facilitating the diagnostic decision are presented. Recent magnetic resonance (MR) studies promise further progress in differentiating between subdural effusions.     

Acinar cell carcinoma of the pancreas ultrasonography and computed tomography findings

The radiologic findings in two cases of acinar cell carcinoma of the pancreas are described. Sonographic findings were a midrange echogenic mass with heterogeneity, containing some small- and medium-sized low echogenic areas suggesting necrosis. Ultrasonic through-transmission was good. Computed tomography findings were a well-defined, hypodense, large mass having an enhancing, thin capsule. There were multiple small- and medium-sized irregular low-density areas suggesting necrosis. Small punctate calcific foci were present in one case. With these characteristics, acinar cell carcinoma can be distinguished from the locally invasive common adenocarcinoma of the pancreas, but the differentiation from some other less common pancreatic tumors remains difficult.     

CT scan and surgery in subdural empyema: a case report

A high index of suspicion is required to pick up cases of subdural empyema in clinical practice. CT scan may be normal in the initial stages. Early neurosurgical intervention is desirable to reduce mortality and morbidity in this condition.     

Oleothorax: expanding pleural lesion

Oleothorax is a method of therapy for pulmonary tuberculosis that was largely abandoned in the 1950s. Its purpose was to cause collapse of the adjacent lung by mechanical means. In the absence of either reactivation of tuberculosis or the development of an empyema, an oleothorax may expand to such an extent as to cause respiratory distress and require removal. The mechanism for this expansion is the stimulation of pleural fluid production by the oil. It is also thought that it may act in a manner similar to a chronic subdural hematoma. This expansion may occur after the oleothorax has been stable for many years, and frequently it is asymptomatic. Four patients were reviewed: one in whom the expansion was so great as to cause respiratory distress, one in whom the enlargement was less rapid and asymptomatic, and two with longstanding oleothoraces in whom the enlargement was more subtle.     

Localisation of intracranial EEG electrodes using three dimensional surface reconstructions of the brain

Subdural strip electrodes or intracerebral electrodes are used to localise epileptic foci, which is imperative in epilepsy surgery. The precise positioning of the subdural electrodes, which is performed via a bore-hole, is difficult. Therefore their location in relation to the gyri and sulci has to be determined by radiological techniques. In this study, a three-dimensional (3D) MRI technique was used for the localisation of intracranial EEG electrodes in 17 patients suffering from severe epilepsy. A 3D gradient echo sequence with slices of 1 mm thickness was required for the assessment of the gyral anatomy of the brain surface. A short repetition time of 30 ms leads to diagnostic image quality and to an acceptable measurment time of about 15 min. Postprocessing with 3D surface reconstruction was performed using a Sun workstation. Three-dimensional reconstruction allows a more precise registration of the localisation of the EEG elctrodes and the simultaneous display of the adjacent brain structures. The incorrect placement of intracranial electrodes was readily detected in 3 patients. Three-dimensional MRI with 3D surface reconstruction proved superior for the assessment of electrocorticogram electrode localisation compared with two-dimensional imaging and CT. Correspondence to: K. Bootsveld     

Subdural empyema: CT findings

CT scans in 49 patients with surgically proven subdural empyema were evaluated. The empyemas were crescentic or lentiform extra-axial hypodense collections (density approximating that of cerebrospinal fluid) with prominent, sharply etched medial rim enhancement. Enhancement of the adjacent cerebral cortex was identified in many cases. Mass effect was always present and in 10 cases so extensive that it overshadowed a small extra-axial collection. CT allowed for precise localization of the lesion, including contiguous or isolated involvement of the interhemispheric subdural space. Mortality was 12% (6/49 cases), a marked improvement when compared with mortality figures obtained prior to the advent of CT (40%). CT findings indicative of involvement of the adjacent parenchyma via retrograde thrombophlebitis with resultant infarction and/or abscess formation were associated with poor prognosis. Improvement in prognosis since the advent of CT is the direct result of early accurate diagnosis and timely intervention.