Cerebral aneurysmal arteriopathy in an adult patient with acquired immunodeficiency syndrome

In adult patients with acquired immunodeficiency syndrome (AIDS), cerebral arteritis usually takes the form of arterial wall thickening, stenosis, and occlusion, leading to cerebral ischemia and infarction. Aneurysms and intracranial hemorrhage are much less commonly associated with cerebral vasculitis. For reasons not entirely clear, this form is seen more often in pediatric patients infected with human immunodeficiency virus. We report an adult patient with cerebral aneurysmal arteriopathy who presented shortly after his AIDS-defining illness in a setting of severe immune suppression and high viral load.

Utilization of glutamate/creatine ratios for proton spectroscopic diagnosis of meningiomas

INTRODUCTION

Our purpose was to determine the potential of metabolites other than alanine to diagnose intracranial meningiomas on proton magnetic resonance spectroscopy (MRS).

METHODS

Using a 1.5-T MR system the lesions were initially identified on FLAIR, and T1- and T2-weighted images. Employing standard point-resolved spectroscopy (PRESS) for single voxel proton MRS (TR 1500 ms, TE 30 ms, 128 acquisitions, voxel size 2 x 2 x 2 cm, acquisition time 3.12 min), MR spectra were obtained from 5 patients with meningiomas, from 20 with other intracranial lesions, and from 4 normal controls. Peak heights of nine resonances, including lipid, lactate, alanine, NAA (N-acetylaspartate), beta/gamma-Glx (glutamate + glutamine), creatine, choline, myo-inositol, and alpha-Glx/glutathione, were measured in all spectra. The relative quantity of each metabolite was measured as the ratio of its peak height to the peak height of creatine.

RESULTS

Relative quantities of alpha-Glx/glutathione, beta/gamma-Glx, and total Glx/glutathione were significantly elevated in meningiomas compared to the 20 other intracranial lesions and the normal control brains. Alanine was found in four of five meningiomas, but lactate partially masked the alanine in three meningiomas. None of the other lesions or control brains showed an alanine peak. The one meningioma with no alanine and the three others with lactate had elevated Glx.

CONCLUSION

While alanine is a relatively unique marker for meningioma, our results support the hypothesis that the combination of glutamate/creatine ratios and alanine on proton MRS is more specific and reliable for the diagnosis of meningiomas than alanine alone.

Embolic stroke complicating Staphylococcus aureusendocarditis circumstantially linked to rectal trauma from foreign body: a first case report

Background

Diagnostic and therapeutic instrumentation of the lower gastrointestinal tract has been reported to result in bacteremia and endocarditis. No such case has been reported in persons with a history of rectal foreign body insertion despite its potential for greater trauma.

Case presentation

A 58-year-old male was admitted with confusion and inability to speak. His past history was notable for hospitalization to extract a retained plastic soda bottle from the rectosigmoid two years prior. On examination, he was febrile, tachycardic and hypotensive. There was an apical pansystolic murmur on cardiac examination. He had a mixed receptive and expressive aphasia, and a right hemiparesis. On rectal examination he had perianal erythema and diminished sphincter tone. Magnetic resonance imaging of the brain showed infarction of the occipital and frontal lobes. Transesophageal Echocardiography of the heart revealed vegetations on the mitral valve. All of his blood culture bottles grew methicillin sensitive Staphylococcus aureus. He was successfully treated for bacterial endocarditis with intravenous nafcillin and gentamicin. The rectum is frequently colonized by Staphylococcus aureus and trauma to its mucosa can lead to bacteremia and endocarditis with this organism.

In the absence of corroborative evidence such as presented here, it is difficult to make a correlation between staphylococcal endocarditis and anorectal foreign body insertion due to patients being less than forthcoming

Conclusion

There is a potential risk of staphylococcal bacteremia and endocarditis with rectal foreign body insertion. Further studies are needed to explore this finding. Detailed sexual history and patient counseling should be made a part of routine primary care.

Intracranial meningeal disease: comparison of contrast-enhanced MR imaging with fluid-attenuated inversion recovery and fat-suppressed T1-weighted sequences

BACKGROUND AND PURPOSE

Contrast-enhanced fluid-attenuated inversion recovery (FLAIR) imaging has been reported to have higher sensitivity for detecting leptomeningeal disease compared with contrast-enhanced T1-weighted MR imaging. The purpose of this study was to compare contrast-enhanced T1-weighted MR images with fat suppression to contrast-enhanced FLAIR images to determine which sequence was superior for depicting meningeal disease.

METHODS

We reviewed MR images of 24 patients (35 studies) with a variety of meningeal diseases. The MR imaging protocol included contrast-enhanced T1-weighted MR images with fat suppression (FS) and contrast-enhanced fluid-attenuated inversion recovery (FLAIR) images that were reviewed by three neuroradiologists and were assigned a rating of positive, equivocal, or negative for abnormal meningeal enhancement. The two sequences were compared side by side to determine which better depicted meningeal disease.

RESULTS

Abnormal meningeal enhancement was positive in 35 contrast-enhanced T1-weighted MR images with FS and in 33 contrast-enhanced FLAIR studies. In the first group, which had the T1-weighted sequence acquired first (21 of 33 studies), contrast-enhanced T1-weighted images with FS showed superior contrast enhancement in 11 studies (52%), inferior contrast enhancement in six studies (29%), and equal contrast enhancement in four studies (19%) compared with the contrast-enhanced FLAIR images. In the second group, which had the FLAIR sequence acquired first (12 of 33), contrast-enhanced T1-weighted images with FS showed superior contrast enhancement in seven studies (58%), inferior contrast enhancement in two studies (17%), and equal contrast enhancement in three studies (25%).

CONCLUSION

Contrast-enhanced T1-weighted MR imaging with FS is superior to contrast-enhanced FLAIR imaging in most cases for depicting intracranial meningeal diseases.

Intracranial spread of Merkel cell carcinoma through intact skull

We report an unusual case of Merkel cell carcinoma presenting as a frontal scalp mass with apparent invasion into underlying brain parenchyma through grossly intact calvaria. Despite wide local excision, craniectomy, intracranial tumor resection, and postoperative adjuvant irradiation, widespread systemic metastases resistant to chemotherapy developed, and the patient died 9 months after surgery. This case report confirms that Merkel cell carcinoma of the head and neck, already known to be an aggressive tumor, has the capacity for rapid intracranial extension. We propose that in this case, the mechanism of intracranial metastasis was via communicating veins rather than through bone destruction or systemic metastasis. Appropriate preoperative imaging should be carried out to define the extent of this tumor when it is adjacent to the skull. We found contrast-enhanced magnetic resonance imaging to be superior to computed tomography for defining soft tissue extent and marrow space involvement within underlying bone.

Polycythemia mimicking venous sinus thrombosis

Venous sinus thrombosis is a relatively uncommon disorder that frequently is associated with confusing clinical findings and delayed diagnosis. Patients are often screened with unenhanced CT, and CT findings may be subtle and may include hyperattenuation of cerebral veins or venous sinuses secondary to intracranial thrombosis. This hyperattenuation may be mimicked by polycythemia, as shown in this case.

Balamuthia amebic encephalitis: radiographic and pathologic findings

The radiographic findings of two patients (one, a rare survivor) with meningoencephalitis caused by Balamuthia mandrillaris are presented with pathologic correlation.

Does tongue size differ between patients with and without sleep-disordered breathing?

OBJECTIVES/HYPOTHESIS

To determine whether there is a difference in the tongue size of patients with and without sleep-disordered breathing (SDB) and to evaluate whether tongue volume correlates with body mass index (BMI), neck circumference, age, Epworth Sleepiness Scale score, or apnea-hypopnea index (AHI).

STUDY DESIGN

Nineteen patients (9 with SDB; 10 without SDB) were enrolled in this prospective study.

METHODS

All patients completed a sleep questionnaire including the Epworth Sleepiness Scale and underwent a physical examination, portable sleep study, and magnetic resonance imaging (MRI) study. An examiner masked to the patients' disease status measured tongue volume from the MRI films.

RESULTS

There was a trend for patients with SDB to have a larger tongue volume than patients without SDB (P = .065). Tongue volume only positively correlated with BMI (P = .005) and neck circumference (P = .013), but there was no correlation with age (P = .23) or AHI (P = .40).

CONCLUSIONS

There is a statistical trend for patients with SDB to have larger tongue size compared with non-SDB patients, but tongue size is independent of AHI and correlates significantly with BMI and neck circumference. We interpret these findings to suggest that variations in tongue size alone cannot account for disease severity and may simply reflect the larger body habitus often seen in patients with SDB.

Unsuspected and unrelated pathology noted on limited computed tomographic scans of the paranasal sinuses and temporal bone

Modern imaging includes many studies performed to examine limited fields of view (i.e., paranasal sinus studies). These studies are frequently retrospectively coned to the limited field of view and are often examined only at one window and level setting. However, classic radiology teaching demands that all irradiated structures be examined by a qualified physician; for examples, on an intravenous pyelogram the examiner should look at not only the kidneys, ureters, and bladder, but also the bones, soft tissues, and gas patterns. This article illustrates unsuspected intracranial pathology noted on computed tomographic examinations of the paranasal sinuses and temporal bones.

Lack of clinically significant gross structural abnormalities in MRIs of older patients with schizophrenia and related psychoses

The authors examined the reports of MRI brain studies of 69 patients with DSM-III-R-diagnosed psychotic disorders (30 early-onset and 24 late-onset schizophrenia patients and 15 with other psychoses) and 41 normal comparison subjects. Participants' ages ranged from 45 to 87 years. A qualitative rating scheme determined type and severity of clinically detectable abnormalities, including volume loss, infarcts, lacunae, and white matter hyperintensities. In this clinically well-characterized sample, the vast majority of the MRIs were within normal limits. There were no significant differences between psychosis patients and normal comparison subjects or between early-onset and late-onset schizophrenia patients in frequency, type, or severity of gross structural abnormalities. The results indicate that late-onset schizophrenia and related disorders can exist without clinically significant gross structural abnormalities in the brain.

Cervical and lumbar MRI in asymptomatic older male lifelong athletes: frequency of degenerative findings

OBJECTIVE

The athletic activity of the adult U.S. population has increased markedly in the last 20 years. To evaluate the possible long-term effects of such activity on the cervical and lumbar spine, we studied a group of asymptomatic currently very active lifelong male athletes over age 40 (41-69 years old, av. age 53).

MATERIALS AND METHODS

Nineteen active, lifelong male athletes were studied with MRI and the results compared with previous imaging studies of other populations. An athletic history and a spine history were also taken.

RESULTS

Evidence of asymptomatic degenerative spine disease was similar to that seen in published series of other populations. Degenerative changes including disk protrusion and herniation, spondylosis, and spinal stenosis were present and increased in incidence with increasing patient age. In this group, all MRI findings proved to be asymptomatic and did not limit athletic activity.

CONCLUSION

The incidence of lumbar degenerative changes in our study population of older male athletes was similar to those seen in other populations.

Metallic spinal artifacts in magnetic resonance imaging

STUDY DESIGN

The magnetic resonance artifact susceptibility of traces of surgical aluminum, titanium, and stainless steel in a human spine model was investigated. Metallic filings were deposited in noncontiguous disc spaces in five human thoracic spines before magnetic resonance imaging with spin echo and gradient echo sequences.

OBJECTIVES

Spin echo and gradient echo sequences were used for quantitate and compare void artifact produced by commonly used surgical metals. This was compared to a liquid paraffin control.

SUMMARY OF BACKGROUND DATA

No significant susceptibility artifact was seen with any metal in all spin echo sequences, including T1 (TR 600, TE 12), T2 (TR 2000, TE 30), proton density (TR 2000, TE 80), and fast T2 scanning (TR 3800, TE 96, Ef).

METHODS

Sagittal magnetic resonance imaging permitted void artifact quantification and comparison between different metallic alloys. Two neuroradiologists, working on a blinded basis, evaluated all data and rated the void susceptibility artifact on a scale of 1 (least) to 4 (greatest).

RESULTS

In general, the magnitude of an imaging artifact during magnetic resonance imaging correlated with the magnetism of the metal. Nickel, found in a larger concentration in 316L than in 304 stainless steel, decreases the magnetic resonance artifact of specific metals because of its ability to stabilize iron in a non-magnetic state. Therefore, the 316L stainless steel yielded less artifact production than 304 stainless steel on gradient echo imaging.

CONCLUSION

If upon gradient echo imaging in the postoperative period significant artifact production is noted, stainless steel deposition should be suspected as the causative agent. In this situation, spin echo techniques should be the first approach for attempting optimal visualization of the spinal cord and soft tissue structures.

MR detection of white matter disease of the brain in patients with HIV infection: fast spin-echo vs conventional spin-echo pulse sequences

OBJECTIVE

Although fast spin-echo images and slower spin-echo images have similar contrast characteristics, the two techniques have not yet been shown to be equivalent in all aspects of brain imaging. To determine if the two sequences are equivalent, we compared detection of white matter lesions, image quality, and artifact degradation on fast spin-echo and spin-echo proton density-weighted and T2-weighted MR images of the brain in prospectively selected patients who were seropositive for HIV.

SUBJECTS AND METHODS

Fast spin-echo and spin-echo MR images of the brain were obtained in 153 consecutive subjects. The images were reviewed independently by three experienced neuroradiologists. The size, number, and location of white matter lesions were compared for the two techniques. Image quality, motion artifact, CSF flow artifact, and gray-white matter differentiation were graded on a five-point scale.

RESULTS

No statistical difference was found in gray-white matter differentiation. Overall image quality, CSF flow artifacts, and motion artifacts were slightly worse on the fast spin-echo images (p < .05). Although some variability existed in the detection of lesions less than 5 mm in diameter, the differences was small, and all larger lesions were detected by both techniques. Agreement between fast spin-echo and conventional spin-echo techniques was nearly exact with respect to characterizing findings in brain as either normal or abnormal.

CONCLUSIONS

Fast spin-echo and spin-echo MR of the brain produce images of similar quality and show white matter lesions equally well. These results support the replacement of slower, conventional spin-echo pulse sequences with faster fast spin-echo sequences.

Enlargement of the superior thyroid artery: an unusual cause for a cervical bruit

An enlarged superior thyroid artery with increased blood flow to a large benign adenomatous goiter was found to be the cause of a bruit in the region of the right carotid bifurcation. We have not been able to find mention of this cause for a cervical bruit in the literature.

Computed tomographic evaluation of metatases to the orbit

The computed tomographic (CT) findings in 22 patients with metastases to the orbit were evaluated. All the metastases appeared to be unilateral on CT. Sixty-eight percent of the patients showed evidence of aggressive adjacent bone destruction. Sixty-eight percent of the patients had intracranial metastatic disease, 46% had direct intracranial extension of the tumor, and 23% had CT evidence of separate intracranial metastases. Fifty-nine percent of the orbital metastases were extraconal, 19% were intraconal, and 19% were both intraconal and extraconal; one case of metastases to the globe was detected. All 13 patients examined before and after contrast showed evidence of enhancement.

The false sulcus: an early sign of intracranial mass

The importance of asymmetry of the cerebral sulci in detecting intracranial mass lesions in the hemisphere where the mass compresses the sulci has been emphasized. Occasionally, the hemisphere that appears to have the large sulci is, in fact, the abnormal side. The apparent large sulci representing early white matter edema are often the earliest computed tomography manifestation of an intracranial mass.

Case report: nonspecificity of multiple lytic skull lesions in the computed tomography evaluation of a cancer patient

The case presented emphasizes the complimentary nature of isotope scanning, CT, and skull radiography in the detection and evaluation of lytic skull lesions. We feel that, if the CT diagnosis of metastatic skull disease is going to change the patient's prognosis and/or therapy, a confirmatory examination, preferably isotope scanning should be undertaken. If the CT and isotope studies are contradictory, skull radiographs may be helpful, the calvarium may be biopsied, or re-examined after an appropriate clinical interval. Multiple lytic areas on a skull CT examination may well represent metastases, but a more benign cause, as illustrated in the case presented, should be considered and ruled out before therapy is instituted.

Computed tomographic evaluation of depressed skull fractures and associated intracranial injury

Thirty-three patients with depressed skull fractures examined by cranial computed tomography were reviewed. CCT not only reveals the vast majority of depressed skull fractures but also reveals underlying hematoma and contusions, delineates the depressed fragment or fragments, and estimates the degree of intracerebral mass effect present. Scans may be grossly abnormal in patients who do well clinically. Thus, while CT findings are important in guiding proper therapy, the clinical status of the patient upon admission has far more prognostic value than the CT findings.

Renal devitalization using 95 per cent ethyl alcohol

Preoperative embolization of renal arteries with solid material before nephrectomy is a standard procedure for the treatment of renal cell carcinoma. However, it often is difficult to use these materials and sometimes special equipment is required. We have used 95 per cent ethyl alcohol in 3 patients to devitalize kidneys with tumors. Our results show 95 per cent ethyl alcohol to be safe, effective and easy to use. When combined with epidural anesthesia alcohol embolization is well tolerated by the patient, and its destructive effect is complete and limited to the selected organ.

Computed tomography of orbital trauma

Ten cases of trauma to the orbit and orbital region are presented to illustrate the efficacy of computed tomography in the radiologic evaluation of these injuries. CT was able to detect subarachnoid hemorrhage, retrobulbar hematoma, orbital cellulitis, foreign bodies, intraglobal and intraorbital air, dislocated lens, blowout, and tripod fractures in these patients.

Postembolic colonic infarction

From a total of 23 cases from five hospitals, acute colonic mucosal necrosis developed in three patients following transcatheter embolotherapy for colonic hemorrhage. Although embolic therapy for lower gastrointestinal bleeding is associated with appreciable risk, these risks are less than those of emergency operation for hemorrhage. The alternative transcatheter therapeutic modality, vasopressin infusion, is often associated with continued or recurrent hemorrhage, is relatively contraindicated in patients with coronary disease, and produces numerous complications. Transcatheter embolotherapy is recommended for patients with colonic bleeding who have a contraindication to vasopressin administration, who are refractory to vasopressin, or who rebleed following treatment with vasopressin.

Raeder syndrome associated with lesions of the internal carotid artery

The authors describe 3 patients with Raeder syndrome who also had lesions of the internal carotid artery in the region of the ascending sympathetic chain. One patient apparently had weakening of the artery wall, caused by extension of inflammatory disease, with hemorrhage brought on by exertion; another patient had a psuedoaneurysm possibly related to biopsy or irradiation, while a third had an aneurysm which may have been caused by a carotid artery dissection at the time of a whiplash injury many years earlier.

Computed tomographic illustration of cavum vergae

This paper presents 3 examples of cavum vergae, a normal variant in cranial computed tomography (CCT) and pneumoencephalography. The CCT appearance of cavum vergae is illustrated in both axial and coronal planes, and the means of distinguishing cavum vergae from cavum velum interpositum and cystic lesions of the third ventricle by reference to normal anatomical landmarks is discussed.

CT of intracranial metastases with skull and scalp involvement

Twenty-eight persons with contiguous intracranial skull, and often extracranial metastatic disease are reported. These lesions comprised 7.6% of a series of 250 consecutive patients with intracranial metastatic disease. Only three of 28 patients had other intracranial lesions and only seven of 28 patients has other skull lesions demonstrable on computed tomography (CT). Carcinoma of the prostate and breast, multiple myeloma, and neuroblastoma are especially likely to appear in this manner. All metastases enhanced. The bone destruction was so pervasive that in 19 of the patients it was obvious at routine CT settings. In the nine other patients, it could be clearly seen only at bone settings (high window and level). The CT demonstration of an enhancing intracranial mass involving the skull and often the scalp is highly suggestive but not diagnostic of a metastatic lesion.

Computed tomography of a cranial wooden foreign body

Wooden foreign bodies have surprisingly low attenuation coefficients and can be difficult to discern on computed tomography when located in the paranasal sinuses or retroorbital fat unless using either a "measured mode" or statistical analysis. A case is presented of a wooden pool cue inserted into a patient's nostril and sinus that illustrates this point.

Intraventricular metastases demonstrated by cranial computed tomography

Intraventricular metastases from extracranial tumors are uncommon. Cranial computed tomography provides a uniquely noninvasive method to diagnose such metastases. However, enhanced intraventricular metastases may mimic normal enhancement of the choroid plexus.