Magnetic resonance of the brain: the optimal screening technique

Magnetic resonance (MR) images and computed tomograms of 25 patients with head trauma were compared. MR proved to be superior in many ways for demonstrating extracerebral as well as intracerebral traumatic lesions. Isodense subdural hematomas, which present a diagnostic dilemma on CT images were clearly seen on MR, regardless of their varying CT densities. In a case of epidural hematoma, the dura mater was shown directly as nearly devoid of signal on MR. Direct coronal images provided excellent visualization of extracerebral collections along the peritentorial space and subtemporal area. In a patient with intracerebral hematoma, CT failed to demonstrate residual parenchymal changes in a 3-month follow-up study, but MR clearly depicted the abnormalities. The superiority of MR over CT was also well illustrated in a patient with post-traumatic osteomyelitis of the calvarium.     

The diagnostic significance of posttraumatic sphenoid sinus effusions: correlation with head computed tomography

In review of 1544 patients with both head computed tomography (CT) examinations and skull radiographs, 150 patients were found to have a history of acute head trauma. Twenty-nine of these patients had sphenoid sinus effusions. Ninety-three percent (27/29) of those cases had abnormal CT examinations, as compared with 48% (58/121) of cases without sphenoid effusions. Of the patients with sphenoid effusions, 31% (9/29) had intracerebral hematomas, 24% (7/29) had extracerebral hematomas, 13% (4/29) had pneumocephalus, and 13% (4/29) had cerebral edema. We conclude that the presence of posttraumatic sphenoid sinus effusion on the skull radiograph is a sensitive sign for intracranial damage and serves as an emergent indication for head CT.     

Privately insured medical patients are more likely to have a head CT

Previous studies suggest overuse disparity of head computed tomography (CT) in white pediatric trauma patients with minor head injuries. Our study is meant to determine if race or insurance status impacts the probability of obtaining head CT in patients with a Glasgow Coma Scale (GCS)?=?15. Using the 2008–2010 National Hospital Ambulatory Medical Care Survey for Emergency Departments (NHAMCS) database, the following variables were analyzed: race, emergency medical services (EMS) arrival, triage category, admission status, gender, age, and insurance status. Patients with injuries were excluded. All patients included had GCS?=?15. In univariate analysis, head CT is more likely to be obtained for patients in the following categories: Medicare insured, private insurance, Medicaid insured, and self-pay, EMS arrival, triage category immediate, and age >75 years. In logistic regression, race (white vs. black) was no longer significant, but there was disparity based on insurance status with privately insured patients more likely to receive a head CT (OR?=?1.683, 95 % CI?=?1.255–2.259). After controlling for the above inclusion variables and focusing on patients less likely to need CT (non-traumatic with GCS?=?15), privately insured patients were more likely to receive a head CT compared with uninsured. Race alone was not associated with an increased probability of receiving a head CT.     

颅内海绵状血管瘤的CT和MRI诊断

目的:探讨脑内与脑外海绵状血管瘤的CT和MRI表现及诊断价值.方法:搜集45例颅内海绵状血管瘤的CT和MRI影像资料进行分析,MRI检查45例,CT检查30例,其中脑内型海绵状血管瘤42例,脑外型海绵状血管瘤3例,均经手术病理证实.结果:脑内型海绵状血管瘤可位于脑内任何部位,单发病灶多见,无明显占位效应,周围无或轻度水肿.CT检查的全部病例呈稍高及混杂密度影27例,增强扫描大都无强化;MRI检查T2 WI表现为"桑葚状"混杂高信号,周围有云絮状低信号环,增强后病灶仅少数轻度强化.脑外型病灶位于中颅窝鞍旁,MRI呈类似哑铃形或类圆形较均匀的稍长T1明显长T2信号,增强扫描呈明显均匀强化.结论:脑内与脑外型海绵状血管瘤的CT和MRI表现具有一定特征,MRI优于CT像,特别是MRI的T2 WI像有助于明确诊断.     

非创伤性股骨头坏死0期临床诊断标准的建立及相关临床研究

目的 探讨股骨头坏死0期临床诊断标准的建立,并通过临床应用验证其准确性和临床价值.方法 回顾性分析临床非创伤性股骨头坏死患者258例,建立非创伤性股骨头坏死0期临床诊断标准,并根据该标准进行临床对照研究.结果 所建立标准的灵敏度、特异度、准确度分别为93.7%、86.4%、89.7%.临床应用研究显示给予预防性治疗(干预组)的患者,其股骨头坏死发生率明显低于无干预组(34.2% vs 84.9%,P＜0.01).结论 确立了非创伤性股骨头坏死0期临床诊断标准,有助于早期发现股骨头坏死,具有重大的临床应用价值;同时发现对0期非创伤性股骨头坏死应用多种预防性综合措施进行干预,治愈率较高,能有效降低股骨头坏死的发病率.     

Diagnostic imaging of subarachnoid hemorrhage

Subarachnoid hemorrhage is characterized by the extravasation of blood into the spaces covering the central nervous system which are filled with cerebrospinal fluid. The leading cause of non-traumatic subarachnoid hemorrhage is rupture of an intracranial aneurysm. Computed tomography (CT) scanning of the head should be the first examination performed in any patient with suspected subarachnoid hemorrhage. The characteristic appearance of extravasated blood is hyperdense. Head CT scanning can also demonstrate intraparenchymal hematomas, hydrocephalus and cerebral edema and can help predict the site of aneurysm rupture.     

Efficacy of computed tomography of the head in changing patient care and health costs: a retrospective study.

Detailed analysis of all neurologic and neurosurgical admissions at Johns Hopkins Hospital for 6 months prior to the second 6 months after installation of a CT head scanner was undertaken in an attempt to identify the effect CT had on health care decisions, costs, and morbidity. Data showed decreased cost of more than $2,000 per patient and shorter length of stay by 7 days in patients with extracerebral collections, and more than $2,500 and 8 days reduction in patients with tumors after CT was in use. A group matched by computer for age, diagnosis, and physician showed decreased costs of more than $2,000 and shortened stay by more than 3 days per hospitalization. Increased costs were shown in patients with cerebrovascular disease after CT. Change in method of workup with fewer invasive studies for all patients (P less than .001) and significant increases in cost of diagnostic workup were demonstrated (P less than .001). There was no change in morbidity and mortality between the two groups. These data suggest that CT of the head may reduce cost and length of hospitalization in certain patient groups and frequently alters patient workup.     

Magnetic resonance imaging in acute head injury

Using cardiorespiratory monitoring and support equipment compatible with a low field (0.15 T) system, magnetic resonance imaging (MRI) of patients suffering acute head injuries proved to be both feasible and safe. An abnormality was demonstrated by magnetic resonance imaging in 46 of 50 patients examined within 7 days of head injury using T2 weighted (SE2200/80) and T1 weighted (IR2000/600/40) multislice sequences. IN contrast, computed tomography (CT) demonstrated abnormalities in only 31 of the 50 patients. Intracranial extracerebral space-occupying collections of blood were well shown by magnetic resonance imaging which provided especially clear definition in the posterior fossa, subtemporal and subfrontal regions. Magnetic resonance imaging was more sensitive to cerebral abnormalities associated with traumatic unconsciousness and detected parenchymal lesions both in patients in coma and in those who had lost consciousness for only a few minutes. Lesions seen with MRI but not with CT included non-haemorrhagic contusions and abnormalities thought to reflect shearing injuries of white matter and intracerebral vessels. Magnetic resonance imaging is an effective alternative to CT; the additional information it can provide should be valuable in increasing the understanding of the early effects and late consequences of a head injury.     

Computed tomographic follow-up of cranio-cerebral injuries in children

38 children with moderate and severe head injuries had CT follow-ups. On initial scans combined lesions dominated over diffuse (diffuse swelling, subarachnoid haemorrhage) and focal lesions (focal swelling, contusions). Contusion showed up until the 6th day after the accident. Two cases of focal lesions could be demonstrated only after intravenous contrast. Up to 40% of the children developed hypodense extracerebral accumulations. Long-term CT follow-ups showed ventricular (84%) and sulcal enlargement (63%) as well as hypodense parenchymal lesions (50%). Combined and diffuse lesions showed a correlation of initial scans and long-term follow-up which could not be demonstrated in case of focal lesions.     

Role of noncontrast head CT in the assessment of vascular abnormalities in the emergency room

Noncontrast CT of the head is a widely used noninvasive investigation for a variety of acute and chronic neurological conditions. Since CT head without contrast is usually the first and often the only investigation in the emergency room for many neurological symptoms, it is imperative to detect subtle vascular changes, which in many patients can be life-saving. The vascular abnormalities may present with increased density and/or size of the vessels, filling defects, and be associated with parenchymal and bony changes. In this article, we present examples of several vascular pathologies which can be identified on the noncontrast CT of the head, and learn imaging and interpretation techniques to help recognize what often are nebulous changes. While some of the findings are diagnostic by themselves and others subtle, any suspicious abnormality should be followed with dedicated vascular imaging such as CT/MR angiogram, venogram, or catheter angiogram for confirmation and better characterization.     

CT对非创伤性急腹症的诊断价值

目的　探讨CT对非创伤性急腹症的诊断价值及合理选用CT检查。方法　回顾分析 3 19例非创伤性急腹症的腹部CT征象。结果　CT检查有阳性者共 2 2 6例 ,阳性率为 70 .84% ,其中泌尿系疾病 63例 ,胆系疾病 62例 ,胰腺疾病 41例 ,胃肠道疾病3 7例 ,其它 2 3例。随着年龄的增长CT发现疾病的阳性率越高。结论　CT对非创伤性急腹症的检查具有诊断价值     

新生儿及婴儿脑外间隙正常演变的CT表现

目的：研究婴儿及新生儿正常脑外间隙的演变过程，以便与病理改变相鉴别。材料和方法：选择因呼吸道感染引起发热，惊厥行头颅ＣＴ检查，而又无阳性发现的９５名２岁以下儿童，将其分为５组，分别测量其额前间隙、纵裂及脑沟。结果：２岁以内小儿脑外间隙的演变过程呈小→大→小的特点，即新生儿脑外间隙较小，２～１２个月的婴儿脑外间隙明显增宽，以２～６个月最宽，以后又逐渐缩小。结论：２～１２个月的婴儿存在较明显的脑外间隙属正常现象，不应误为病理改变。     

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.     

影像学检查在非创伤性急腹症诊断中的临床应用价值比较研究

目的：探讨不同影像学检查方法在非创伤性急腹症诊断中的应用价值,为临床实践中影像学检查的合理选择提供依据。方法回顾性分析135例诊断明确,临床资料完整的非创伤性急腹症病例的腹部X线片、超声、CT等影像资料,统计不同影像学检查对非创伤性急腹症的符合率。结果135例非创伤性急腹症中, X线片的符合率23．7％;超声符合率为32．6％;CT的符合率为87．4％。其中X线片在诊断肠梗阻、消化道穿孔中符合率分别为74．2％、68．8％;超声在胆系结石诊断中的符合率为65．4％;CT则在整体急腹症诊断符合率具有明显优势,三者差异有统计学意义（χ2=504．11,P＜0．05）。结论合理使用影像学检查技术能有效提高非创伤性急腹症的诊断符合率,使急腹症患者得到及时、准确、有效的治疗,减少并发症的发生。     

Cerebral perfusion deficit masked by Paget's disease of skull

Prominent extracerebral perfusion on an emission angiogram of the head in a patient with Paget's disease of the skull masked an underlying intracerebral perfusion deficiency, due to occlusion of the left middle cerebral artery.     

Chronic focal fibrosing pancreatitis: detection by MRI.

The study of a 70-year-old woman with fibrosing pancreatitis, an uncommon variety of chronic pancreatitis, presenting as a discrete solid mass in the head of the pancreas, is reported. CT and US were non-diagnostic while ERCP and MR detected a focal anomaly. This case report stresses the sensitivity of MR in some pancreatic pathologies.     

Comparative sensitivity of CT scans, radiographs and radionuclide bone scans in detecting metastatic calvarial lesions

CT scans of 100 patients with histologically diagnosed extracerebral neoplasms were reviewed and compared with either radionuclide bone images or skull radiographs. The results of this correlative study indicate that CT scans are more sensitive than skull radiographs in detecting corresponding calvarial lesions; conversely, radionuclide bone scans appear to be more sensitive than CT in detecting similar lesions.     

Value of abdominal CT in the emergency department for patients with abdominal pain

The purpose of our study is to demonstrate the value of CT in the emergency department (ED) for patients with non-traumatic abdominal pain. Between August 1998 and April 1999, 536 consecutive patients with non-traumatic abdominal pain were entered into our study. Using a computer order entry system, physicians were asked to identify: (a) their most likely diagnosis; (b) their level of certainty in their diagnosis; (c) if they thought CT would be normal or abnormal; (d) their treatment plan (prior to knowledge of the CT results); and (e) their role in deciding to order CT. This information was correlated with each patient's post-CT diagnosis and subsequent management. Pre- and post-CT diagnoses were concordant in 200 of 536 (37%) patients. The physicians' certainty in the accuracy of their pre-CT diagnosis was less than high in 88% of patients. Prior to CT, the management plan included hospital admission for 402 patients. Following CT, only 312 patients were actually admitted; thus, the net impact of performing CT was to obviate the need for hospital admission in 90 of 536 (17%) of patients with abdominal pain. Prior to CT, 67 of 536 (13%) of all patients would have undergone immediate surgery; however, following CT only 25 (5%) actually required immediate surgery. Among patients with the four most common pre-CT diagnoses (appendicitis, abscess, diverticulitis, and urinary tract stones) CT had the greatest impact on hospital admission and surgical management for patients with suspected appendicitis. For patients with suspected appendicitis, CT reduced the hospital admission rate in 28% (26 of 91) of patients and changed the surgical management in 40% (39 of 91) of patients. Our study demonstrates the advantage of performing abdominal CT in the ED for patients with non-traumatic abdominal pain. Electronic Publication     

Lymph node pathology. Benign proliferative, lymphoma, and metastatic disease

The evaluation of cervical lymph nodes is one of the main indications for performing CT and MR imaging of the neck. Imaging may be done for evaluation of an unknown neck mass, but more commonly the neck is imaged to evaluate potential metastasis from a known mucosal malignancy. CT and MR imaging characteristics of both malignant and nonmalignant nodal diseases are reviewed and the differential diagnosis of nodal pathologies for specific imaging findings are discussed. A recently proposed imaging-based nodal classification for metastatic nodal diseases from head and neck cancer is also described.     

CT and MR of the brain in glutaric acidemia type I: a review of 59 published cases and a report of 5 new patients.

PURPOSETo identify a pattern of findings on CT or MR of the brain in glutaric acidemia type I typical enough to permit a correct diagnosis.METHODSClinical history and findings and brain CT and MR results in 59 previously reported patients (MR in 12) and in 5 new patients (all examined with MR and 3 also with CT) were reviewed.RESULTSIn half the patients macrocephaly was present, and in half the onset was acute, often following infection and mimicking encephalitis. Although brain atrophy or hypoplasia was found in 61% and white matter changes in 51% of the patients, open opercula (usually very widely open) and often also wide cerebrospinal fluid spaces anterior to the temporal lobes were seen in 93%. Basal ganglia lesions, presenting as volume loss and high T2 signal in the caudate head and often also the lentiform nucleus bilaterally, were found in 44% and extracerebral fluid collections in 7 of 64 patients.CONCLUSIONThe finding of very widely open opercula suggests glutaric acidemia type I, and if combined with basal ganglia lesions is almost pathognomonic, especially in a child with macrocephaly.