Spinal bone marrow necrosis with vertebral compression fracture: differentiation of BMN from AVN.

Bone marrow necrosis (BMN) is a rare malignancy-associated hematologic disorder characterized by necrosis of myeloid and stromal marrow elements with preservation of cortical bone. Overlap between the imaging appearances of BMN and avascular necrosis (AVN) raises the potential for diagnostic confusion. We report a case of BMN presenting with a traumatic multi-level vertebral body collapse, and finding that may potentially confound distinction between the two entities. We discuss important pathophysiologic, clinical, and radiologic differences between BMN and AVN with emphasis on features important in the differential diagnosis.

CT-guided biopsy of focal lesions in patients with multiple myeloma may reveal new and more aggressive cytogenetic abnormalities.

BACKGROUND AND PURPOSE: Cytogenetic abnormalities, especially chromosome 13 deletion, are high-risk factors for multiple myeloma. Attaining the highest detection rates of cytogenetic abnormalities is important to provide accurate prognostic information to the referring oncologist. The purpose of this study was to use CT-guided percutaneous fine-needle aspiration bone biopsy (CT-guided FNA) of MR-detected focal lesions in patients with multiple myeloma to increase identification of abnormal cytogenetics. METHODS: Patients enrolled in two clinical trials for myeloma therapy underwent MR imaging of the entire spine and pelvis. CT-guided FNA biopsy samples obtained from MR-detected focal lesions in these patients were sent for cytogenetic analysis. FNA results were then compared with random bone marrow sampling of the iliac crest done at or near the same time as the FNA to provide the data revealed in this study. RESULTS: Forty-one patients (47 lesions) in one of the trials and 37 patients (38 lesions) in the other trial had biopsies performed. CT-guided FNA revealed cytogenetic abnormalities in 21% of the total patient population and new information in nearly 10% of the patients in one trial and in 20% of those in the other trial. CONCLUSION: CT-guided biopsy of MR-detected focal lesions is a safe technique that can provide important cytogenetic information in a significant number of patients with multiple myeloma not identified during random marrow sampling.

Intrathecal cytotoxic T-cell immunotherapy for metastatic leptomeningeal melanoma.

A 49-year-old patient with primary, recurrent melanoma on the lower extremity developed metastatic leptomeningeal melanoma that did not respond to treatment with radiation therapy or intrathecal interleukin 2 (IL-2). Disease was characterized by neurological symptoms, including loss of hearing, loss of short-term memory, and gait disturbance. CD8+ CTLs were generated in vitro using autologous dendritic cells pulsed with peptides from the melanoma-associated antigens tyrosinase (145-156), Melan-A/MART-1 (26-35), and gp100/Pmel 17 (209-217). The CTLs exhibited up to 74% specific lysis against peptide-pulsed autologous EBV-transformed B cells, with Melan-A-specific CTLs yielding the greatest lytic activity. CD8+ CTLs possessed a type 1 cytokine profile, expressing tumor necrosis factor alpha and IFNgamma but not IL-4. Infusions of CTLs were supported with systemic low-dose IL-2 administration. 111In labeling and computerized gamma imaging were used to monitor the distribution of CTLs up to 48 h after infusion. Intra-arterial delivery via the right carotid artery was followed by redistribution of the CTLs to the lungs, liver, and spleen within 16 h. In contrast, delivery via an indwelling Ommaya reservoir resulted in prolonged retention of CTLs within the brain for at least 48 h after infusion. Marked but transient elevations in tumor necrosis factor alpha, IFN-gamma, and IL-6 in the cerebrospinal fluid were observed within 4 h of CTL infusion. There was no evidence of tumor progression throughout the treatment period, and clinically the patient showed some resolution of neurological symptoms.

Intracranial aneurysms in infants and children.

BACKGROUND: The diagnosis and imaging of pediatric aneurysms has changed since the advent of MR and MRA. OBJECTIVE: To update the literature on pediatric aneurysms and better define the appropriate work-up of childhood aneurysms in 1997. MATERIALS AND METHODS: Retrospective review of 21 children (12 boys, 9 girls) with 25 aneurysms from three institutions over a 20-year period was performed. Imaging studies were mixed and included CT (19 patients), MR (11 patients), MRA (6 patients) and angiography (18 patients). RESULTS: Eighteen of 25 aneurysms were congenital saccular, 6 were mycotic, and 1 was post-traumatic. Of these, 44 % were in the posterior circulation. Nine aneurysms arose from distal arterial branches. Forty percent were large (between 1-2.5 cm) and 16 % were giant (> 2.5 cm). CT and MR showed hemorrhage, and frequently revealed the aneurysms as a focal mass with or without enhancement and flow void. Six children had MRA which revealed aneurysms in four patients. All patients with MRA had corresponding conventional angiography. CONCLUSION: Characteristics of pediatric aneurysms include diversity of type, increased incidence in the posterior fossa, peripheral location, and large size. CT, MR and MRA are useful in the diagnosis with conventional angiography essential for preoperative planning.

MR and CT diagnosis of carotid pseudoaneurysm in children following surgical resection of craniopharyngioma.

We report the cases of two children who underwent CT, MR, MRA and angiography in the diagnosis of postoperative aneurysmal dilatation of the supraclinoid carotid arteries following surgical resection of craniopharyngioma. Craniopharyngiomas are relatively common lesions, accounting for 6-7% of brain tumors in children. They are histologically benign, causing symptoms by their growth within the sella and suprasellar cistern with compression of adjacent structures, especially the pituitary gland, hypothalamus and optic nerves, chiasm, and tracts. Complete surgical resection, particularly of large tumors, is complicated by the fact that the lesions are usually found within the circle of Willis, with displacement and adherence to the adventitia of these vessels [1, 2]. Recent reports in the neurosurgical literature have described aneurysmal dilatation of the supraclinoid internal carotid arteries following aggressive surgical resection of craniopharyngioma [3, 4].

Head and neck MR angiography in pediatric patients: a pictorial essay.

Magnetic resonance (MR) angiography is a new, noninvasive imaging method with well-known uses in adults for the evaluation of carotid disease in the neck and cerebral vasculopathy. MR angiography examinations were prospectively studied in 126 children to evaluate the usefulness of MR angiography of the head and neck in children, as well as to correlate its findings with those of conventional angiography. Eleven patients underwent conventional angiography in addition to MR angiography. MR angiography was performed with commercially available pulse sequences and included two- and three-dimensional time-of-flight and phase-contrast techniques. Indications for MR angiography included evaluation of pathologic conditions (aneurysms and arteriovenous malformations, infarcts, venous sinus thrombosis, brain tumors, and cerebritis), screening examinations in sickle cell disease, and follow-up of extracorporeal membrane oxygenation. MR angiography was found to be a useful, noninvasive diagnostic and screening examination for head and neck and cerebral vascular abnormalities in children and had excellent correlation with conventional angiography.

Prenatal diagnosis of central nervous system abnormalities.

Fetal anomalies have been the subject of innumerable publications both in the prenatal and neonatal literature. This has significantly increased in the last 10 years, mainly because of the advent of high-resolution ultrasound equipment and improvement of scanning techniques. In addition, guidelines issued by professional organizations involved in prenatal diagnosis have encouraged a more universal approach to the imaging and documentation of prenatal findings. The fetal central nervous system is the most frequently investigated organ system, mainly because of its easy accessibility and prominence even in the early stages of embryologic development. The biparietal diameter was the first fetal measurement to be widely used in determining gestational age. As investigators gained more experience, the appearance of ultrasound images achieved the resolution that allows direct comparisons with gross specimens and more recent sophisticated techniques of computed tomography and magnetic resonance imaging. Now endovaginal ultrasound can document early first trimester development and compare it to known embryologic landmarks. Interest in demonstrating the ultrasound counterpart of central nervous system structures in the early stages of development has resulted in a plethora of articles proving the unique ability of ultrasound in imaging the developing fetus. In view of all these developments, the beginning ultrasound specialist is faced with the challenge and responsibility not only of being familiar with the literature but also of the mastery of scanning techniques that allow accurate prenatal diagnosis. It is therefore helpful to review key developmental milestones in embryologic life and correlate them with the corresponding prenatal ultrasound appearance. In addition, the changing appearance of the developing fetus has created a need for a systematic approach in the evaluation of structures so routine protocols can be established. This has been the subject of other publications that allow the novice to draw from the cumulative experience of different centers around the world. It is important to pay attention to the specifics described in the literature when duplicating results in one's laboratory. The frustration of not being able to reproduce results is common, especially when technical limitations prevent imaging under ideal conditions. This is especially true in patients who are first seen in the later third trimester with no prior prenatal care.(ABSTRACT TRUNCATED AT 400 WORDS)

MR findings in childhood gangliogliomas.

Gangliogliomas are uncommon primary brain tumors composed of atypical glial and neuronal cells. These tumors usually occur in children and young adults. They are slow-growing tumors that present with seizures. We have reviewed four cases from our institution and have correlated the magnetic resonance (MR) findings with CT and histology. Two distinct patterns were observed with MR. In three of four patients, ranging in age from 7 to 14 years, MR showed a mass with decreased signal on T1-weighted images (WI) and increased signal on T2WI. The most common CT finding was a hypodense enhancing mass with focal calcifications. The histologic features of these tumors comprised microcysts and hypervascularity. In one of four patients, an infant. MR showed increased signal on T1WI and decreased signal on T2WI. Computed tomography showed a hyperdense nonenhancing mass. Histology demonstrated an increase of hypercellularity with both atypical glial and neuronal components.

MRI in the evaluation of spina bifida patients in the remote period after meningomyelocele repair.

MRI was performed on 22 patients ranging in age from 3 months to 16 years who had closure of their meningomyelocele shortly after birth. These patients had developed new clinical findings suggestive of spinal cord dysfunction. MRI showed low placement of the spinal cord in all 22. Six patients had lipomas, five had diastematomyelia and six had hydromyelia. Four patients had an obviously dysplastic terminal cord.

Craniopharyngioma presenting as a nasopharyngeal mass: CT and MR findings.

Craniopharyngiomas usually arise in the suprasellar or parasellar region. The occurrence of the tumors in other locations is rare and they have to be distinguished from lesions in the suprasellar or sellar region with unusual extension. Thus far, few craniopharyngiomas of infrasellar origin have been described. We report a case in which the tumor presented as a nasopharyngeal mass and CT and magnetic resonance were used for evaluation. Review of the pertinent embryology and literature is also included.

Spine: device to facilitate surface coil MR imaging.

A device was constructed to allow rapid adjustment of the position of a surface coil in magnetic resonance (MR) imaging of the spine. The device consists of two sheets of acrylic plastic and a movable sled. The surface coil is placed on the sled and can be precisely moved superiorly or inferiorly with a cord attached to the sled. The device can save approximately 30 minutes during MR imaging of the entire spine and increases patient comfort and cooperation.

Ocular involvement in mycotic sinusitis caused by Bipolaris.

We examined two patients with unilateral ophthalmologic findings secondary to pansinusitis caused by Bipolaris. Both patients were healthy young men. One patient had a gradual visual loss, whereas the other showed proptosis. Surgical debridement was the primary treatment in both patients. One patient received antifungal therapy, whereas the other was cured with surgery alone.

MR imaging of spinal epidural sepsis.

Four patients with spinal epidural sepsis were evaluated with MR imaging. The lesions were best visualized with spin-echo techniques with long repetition (2000 msec) and long echo (80-100 msec) times. Sagittal and axial images were equally important in defining the extent of the lesions. Comparison with available contrast-enhanced CT scans showed that MR was more definitive in the early demonstration of the abscesses. This early recognition influenced the management greatly and improved the clinical outcome significantly. The findings in our four cases support previous reports that MR is superior to other imaging methods for early recognition and anatomic localization of infectious diseases in patients suspected of having either spinal osteomyelitis or spinal epidural sepsis.

Oculomotor palsy and papilledema with pial-dural arteriovenous malformation.

A 62-year-old man presented with papilledema, a cranial bruit, and a partial left oculomotor nerve palsy. Arteriography revealed a large mixed pial-dural arteriovenous malformation involving the superior sagittal and both transverse sinuses. After the superior part of the malformation was embolized, the patient's papilledema and ocular motility disturbance resolved. The oculomotor disturbance may have been a nonspecific sign of increased intracranial pressure. Cranial auscultation should be performed in all cases of papilledema and cranial nerve palsy.

High-resolution computed tomography in intracranial aneurysms.

High-resolution computed tomography in intracranial aneurysms is a highly valuable procedure. Its indications are as follows: to determine the presence of subarachnoid hemorrhage and to predict the location of aneurysms; to identify and characterize saccular and giant aneurysms; to assess the complications of aneurysm rupture; to evaluate operative maneuvers and postoperative complications. The technique of high resolution computed tomography consists of unenhanced and enhanced 10-mm-thick sections followed by 1.5mm thin sections through suspicious areas. A bolus of 100cc of 60% meglumine diatrizoate is given for the enhanced study. A repeat bolus of 60cc of contrast agent is administered prior to the thin sections. Direct coronal scanning and sagittal/coronal reformatting is frequently used. This review will detail the technique used in this procedure as well as present examples of the major indications listed above. This is the procedure of choice for patients suspected of having had a subarachnoid hemorrhage or harboring an intracranial aneurysm.