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Spatial intratumor heterogeneity is frequently seen in multiple myeloma (MM) and poses a significant challenge for risk classifiers, which rely on tumor samples from the iliac crest. Because biopsy-based assessment of multiple skeletal sites is difficult, alternative strategies for risk stratification are required. Recently, the size of focal lesions (FLs) was shown to be a surrogate marker for spatial heterogeneity, suggesting that data from medical imaging could be used to improve risk stratification approaches. Here, we investigated the prognostic value of FL size in 404 transplant-eligible, newly diagnosed MM patients. Using diffusion-weighted magnetic resonance imaging with background suppression, we identified the presence of multiple large FLs as a strong prognostic factor. Patients with at least 3 large FLs with a product of the perpendicular diameters >5 cm 2 were associated with poor progression-free survival (PFS) and overall survival (OS; median, 2.3 and 3.6 years, respectively). This pattern, seen in 13.8% of patients, was independent of the Revised International Staging System (RISS), gene expression profiling (GEP)-based risk score, gain(1q), or extramedullary disease (hazard ratio, 2.7 and 2.2 for PFS and OS in multivariate analysis, respectively). The number of FLs lost its negative impact on outcome after adjusting for FL size. In conclusion, the presence of at least 3 large FL is a feature of high risk, which can be used to refine the diagnosis of this type of disease behavior and as an entry criterion for risk-stratified trials., (© 2018 by The American Society of Hematology.)

Objective: We aimed to evaluate the use of 4-dimensional computed tomography (4DCT) for characterization of thyroid nodules., Methods: Our study drew from 100 consecutive patients with primary hyperparathyroidism who underwent 4D parathyroid CT imaging for adenoma localization. Included subjects had tissue sampling of a thyroid nodule within 3 months of 4DCT., Results: Twenty subjects (18 women and 2 men) had thyroid nodules that were pathologically confirmed. Precontrast nodule attenuation was significantly lower in malignant nodules when compared with benign nodules (36 vs 61 HU, P = 0.05). Arterial phase and delayed phase nodule attenuations were not significantly different in malignant and benign nodules (128 vs 144 HU, P = 0.7; 74 vs 98 HU, P = 0.3)., Conclusions: Our initial experience with a small group of patients was unable to support the use of 4DCT for characterizing thyroid nodules; however, precontrast nodule attenuation was significantly lower in malignant nodules when compared with benign nodules.

Epilepsy is very rarely attributed to posterior reversible encephalopathy syndrome (PRES). We report the case of a previously healthy 21-year-old who developed epilepsy with mesial temporal sclerosis following an episode of PRES related to a complicated Cesarean delivery. Neuroimaging at the time of PRES and 3 months after revealed the development of unilateral hippocampal volume loss following resolution of acute PRES-related brain edema. We discuss the incidence and importance of "non-reversible" sequelae of PRES and their implications for patient care.

Posterior reversible encephalopathy syndrome (PRES) is a neurotoxic process that typically occurs in the setting of immune dysregulation. In contrast to the characteristic pattern involving parieto-occipital and posterior frontal regions, predominant involvement of the infratentorial brain occurs in a minority of PRES patients. We examined six patients with infratentorial predominant posterior reversible encephalopathy syndrome (IPPRES) relative to those with typical PRES in terms of clinical factors of toxicity and outcomes. We review the current understanding of PRES pathophysiology. An institutional database of PRES patients was created through an IRB-approved search of the electronic record from 2007 to 2012. MR images were reviewed and classified by two neuro radiologists. Clinical data including laboratory data, blood pressure, and discharge outcome were collected through review of existing electronic medical records. Characteristics of the two groups were compared. Six cases among 80 PRES patients displayed an atypical distribution of signal abnormality predominantly involving the infratentorial brain. In IPPRES patients, signal abnormalities within the supratentorial brain, when present, showed a predominantly central distribution rather than the typical peripheral distribution. IPPRES patients showed higher rates of extreme hypertension, renal dysfunction, abnormal serum calcium, and abnormal serum magnesium relative to typical PRES patients. Outcomes were similar between the two groups. In our small series, IPPRES differs from typical PRES patients not only in the distribution of imaging abnormalities but also in rates of extreme hypertension and several laboratory indices. Despite these differences, clinical outcome in the IPPRES group was similar to that of typical PRES.

We report two cases of posterior reversible encephalopathy syndrome (PRES) occurring in association with supra-therapeutic serum lithium levels. Although the neurologic manifestations of lithium toxicity are well known, this is, to our knowledge, the first report describing a link between lithium toxicity and PRES. We discuss the current understanding of the pathogenesis of PRES and suggest mechanisms by which lithium may play a role in its development., (Copyright © 2014 by the American Society of Neuroimaging.)

The pathophysiology of posterior reversible encephalopathy syndrome (PRES) is incompletely understood; however, an underlying state of immune dysregulation and endothelial dysfunction has been proposed. We examined alterations of serum lactate dehydrogenase (LDH), a marker of endothelial dysfunction, relative to the development of PRES in patients receiving chemotherapy. A retrospective Institutional Review Board approved database of 88 PRES patients was examined. PRES diagnosis was confirmed by congruent clinical diagnosis and MRI. Clinical features at presentation were recorded. Serum LDH values were collected at three time points: prior to, at the time of, and following PRES diagnosis. Student's t-test was employed. LDH values were available during the course of treatment in 12 patients (nine women; mean age 57.8 years [range 33-75 years]). Chemotherapy-associated PRES patients were more likely to be normotensive (25%) versus the non-chemotherapy group (9%). LDH levels at the time of PRES diagnosis were higher than those before and after (p=0.0263), with a mean difference of 114.8 international units/L. Mean time intervals between LDH measurement prior to and following PRES diagnosis were 44.8 days and 51.4 days, respectively. Mean elapsed time between last chemotherapy administration and PRES onset was 11.1days. In conclusion, serum LDH, a marker of endothelial dysfunction, shows statistically significant elevation at the onset of PRES toxicity in cancer patients receiving chemotherapy. Our findings support a systemic process characterized by endothelial injury/dysfunction as a factor, if not the prime event, in the pathophysiology of PRES., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

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.

Sinonasal imaging is performed in 2 major clinical scenarios: inflammatory rhinosinusitis or suspected mass lesion. Rhinosinusitis affects more than 16% of the US population annually. It poses an immense economic burden, accounting for more than 26 million outpatient visits annually and costing more than $4.3 billion annually in direct medical expenses. Most cases of uncomplicated acute and subacute rhinosinusitis are diagnosed clinically and should not require any imaging procedure. CT of the sinuses without contrast is the imaging method of choice in patients with recurrent acute sinusitis or chronic sinusitis. Sinusitis cannot be diagnosed on the basis of imaging findings alone. CT scan findings should be interpreted in conjunction with clinical and endoscopic findings. MRI is currently used for evaluation of sinus disease as a complementary study in cases of aggressive sinus infection with ocular/intracranial complications, potential invasive fungal sinusitis in immunocompromised patients or in the evaluation of a sinonasal mass. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances where evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment., (Copyright © 2013 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Myelopathy is a problem that requires imaging to distinguish among numerous specifically treatable causes. The first priority is to determine mechanical stability after trauma. Next, it is crucial to distinguish intrinsic disease from extrinsic compression-for example, by epidural abscess. Osteophytes or disc extrusions and metastatic compression are the most common causes of extrinsic lesions. Imaging approaches rely on clinical features such as pain, fever, trauma, and pattern of progression. CT is preferred initially in acute trauma and MRI in all other circumstances. Contrast-enhanced MRI is added when tumor or infection is suspected or with slow or stepwise progression, especially when pain is not prominent. Vascular imaging is used when arteriovenous malformation, fistula, or occlusive disease is suspected. Because the treatment of myelopathy is often complex, treatment planning may require more than one imaging study or sequential examination to assess interval change. The ACR Appropriateness Criteria(®) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment., (Copyright © 2012 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Stroke is the sudden onset of focal neurologic symptoms due to ischemia or hemorrhage in the brain. Current FDA-approved clinical treatment of acute ischemic stroke involves the use of the intravenous thrombolytic agent recombinant tissue plasminogen activator given <3 hours after symptom onset, following the exclusion of intracerebral hemorrhage by a noncontrast CT scan. Advanced MRI, CT, and other techniques may confirm the stroke diagnosis and subtype, demonstrate lesion location, identify vascular occlusion, and guide other management decisions but, within the first 3 hours after ictus, should not delay or be used to withhold recombinant tissue plasminogen activator therapy after the exclusion of acute hemorrhage on noncontrast CT scans. MR diffusion-weighted imaging is highly sensitive and specific for acute cerebral ischemia and, when combined with perfusion-weighted imaging, may be used to identify potentially salvageable ischemic tissue, especially in the period >3 hours after symptom onset. Advanced CT perfusion methods improve sensitivity to acute ischemia and are increasingly used with CT angiography to evaluate acute stroke as a supplement to noncontrast CT. The ACR Appropriateness Criteria(®) are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment., (Copyright © 2011 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

An ectopic location of pituitary adenoma is rare. Nasopharyngeal location of ectopic pituitary adenoma has been attributed to remnants of the Rathke pouch. We describe an interesting case of ectopic pituitary adenoma in the setting of partially persistent craniopharyngeal canal. Embryological basis of ectopic pituitary adenoma and craniopharyngeal canal have been discussed.

A 27-year-old pregnant woman reported progressive loss of vision. Brain MRI disclosed an intracranial mass compressing the optic nerves and chiasm with imaging features suggestive of meningioma. Because delivery was imminent, surgical removal was deferred. Within a few days after delivery, the patient noted improvement in vision. Subsequent neuro-ophthalmological evaluations documented almost complete visual recovery within 2 months postpartum. The mass was removed surgically at 10 months postpartum. It was a grade I meningioma with progesterone cell surface receptors. The patient's visual function has remained stable during a follow-up of 14 months. This is the first reported case with full visual function and MRI documentation of spontaneous postpartum visual recovery in a progesterone receptor-positive meningioma compressing the anterior visual pathway.

Intertemporal choice is predicated on the valuation of commodities with respect to delay until their receipt. Subjective value of a future outcome decreases, or is discounted, as a function of that delay (Bickel and Johnson, 2003). Although behavioral studies suggest no difference between the devaluation of real and fictive outcomes, no neuroimaging studies have investigated potential differences in the underlying deliberative process. Here, we compare behavioral and neural correlates of intertemporal valuation of real and hypothetical monetary gains as well as hypothetical losses, which have been posited to involve different mechanisms. Behavioral and neuroimaging sessions were conducted in which participants made intertemporal choice decisions in a gains condition using both real and hypothetical $100 money and in a loss condition using a fictive $100 money. Within-subject comparison of behavioral data revealed no significant difference between levels of discounting across the three conditions. Random-effects analysis of functional magnetic resonance imaging (fMRI) data of each of the three discounting conditions independently revealed significant signal change in limbic (anterior cingulate, striatum, posterior cingulate) and executive functioning areas (lateral prefrontal cortex), whereas a repeated-measures ANOVA failed to detect differences in signal change across the three discounting conditions after correcting for multiple comparisons. These data support a concordance between real and hypothetical conditions from delay-discounting studies and further suggest a congruence of the fMRI blood oxygen level-dependent signal across brain regions associated with the deliberative process of different forms of intertemporal choice.

Purpose: Magnetic resonance imaging (MRI) permits the detection of diffuse and focal bone marrow infiltration in the absence of osteopenia or focal osteolysis on standard metastatic bone surveys (MBSs)., Patients and Methods: Both baseline MBS and MRI were available in 611 of 668 myeloma patients who were treated uniformly with a tandem autologous transplantation-based protocol and were evaluated to determine their respective merits for disease staging, response assessment, and outcome prediction., Results: MRI detected focal lesions (FLs) in 74% and MBS in 56% of imaged anatomic sites; 52% of 267 patients with normal MBS results and 20% of 160 with normal MRI results had FL on MRI and MBS, respectively. MRI- but not MBS-defined FL independently affected survival. Cytogenetic abnormalities (CAs) and more than seven FLs on MRI (MRI-FLs) distinguished three risk groups: 5-year survival was 76% in the absence of both more than seven MRI-FLs and CA (n = 276), 61% in the presence of one MRI-FL (n = 262), and 37% in the presence of both unfavorable parameters (n = 67). MRI-FL correlated with low albumin and elevated levels of C-reactive protein, lactate dehydrogenase, and creatinine, but did not correlate with age, beta-2-microglobulin, and CA. Resolution of MRI-FL, occurring in 60% of cases and not seen with MBS-defined FL, conferred superior survival., Conclusion: MRI is a more powerful tool for detection of FLs than is MBS. MRI-FL number had independent prognostic implications; additionally, MRI-FL resolution identified a subgroup with superior survival. We therefore recommend that, in addition to MBS, MRI be used routinely for staging, prognosis, and response assessment in myeloma.

Multiple myeloma (MM) is a malignant clonal neoplasm of plasma cells of B-lymphocyte origin that commonly results in overproduction of large amounts of monoclonal immunoglobulins. Important advances in the therapeutic management of this disease in the past decade have resulted in higher rates of durable complete remission, prolonged event-free survival, and improved overall survival. Clearer understanding of the effects of abnormal plasma cells on bone has led to therapeutic approaches that help prevent vertebral body fractures. Current imaging technologies and, in particular, survey marrow studies with magnetic resonance (MR) imaging have improved detection of the extent and location of disease in MM patients. In newly diagnosed cases, MR surveys of the axial skeleton accurately demonstrate the extent of disease-diffuse or focal involvement-and the presence of associated compression fractures and cord compression. After treatment, MR images show the effects of treatment and the presence of residual disease. Multiple sites of focal bone lesions detected on MR studies allow a more appropriate choice of biopsy site than the usual random iliac marrow biopsy. Use of MR to determine biopsy sites and computed tomographic guidance for biopsy performance have increased the safety and accuracy of sampling. These biopsies have resulted in increased identification of cytogenetic abnormalities, particularly the presence of chromosome 13 deletion, which is a grave prognostic indicator in MM., (Copyright RSNA, 2004)

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.

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.

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.

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].

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.

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)

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.

The value of digital pulmonary arteriography and balloon-occlusion cineangiography was investigated in 118 selected patients. In one series of 40 patients, digital pulmonary arteriography correctly identified pulmonary emboli in 20 (75%) of 26 positive examinations when interpretation was confined to the first three divisions of the pulmonary artery. In a second series of 78 patients with peripheral radionuclide perfusion scan defects, 40 of whom had pulmonary emboli, adjunctive balloon-occlusion cineangiography demonstrated emboli in four patients not seen on standard selective catheter pulmonary magnification studies with cut films. These two procedures (i.e., digital pulmonary arteriography and balloon-occlusion cineangiography) are important adjuncts to radionuclide perfusion scans and selective catheter pulmonary arteriography in the evaluation of patients with pulmonary emboli.

Vascular malformations of the mediastinum are rare tumors. Computed tomography with dynamic scans was helpful in demonstrating the vascular component of a mediastinal mass presenting in a 10-year-old child.

The present report demonstrates a complication not previously reported secondary to thyroid surgery as a treatment of hyperthyroidism. This complication of a sinus tract extending 6 cm from the thyroid to the skin appeared to be due to a foreign body reaction to the sutures utilized in the operation. This sinus tract which extruded some sutures became infected with Staphylococcus aureus which prevented spontaneous closure. The formation of a sinus tract in the neck after a subtotal thyroidectomy for hyperthyroidism appears to be a much less common complication than the previously reported complications of bilateral abductor vocal fold paralysis, unilateral recurrent nerve paralysis, permanent post-operative hypoparathyroidism and thyroid storm secondary to this surgery, but the true incidence of sinus tract formation after thyroid surgery is unknown at present.

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.

The finding of mature neuroglial tissue in a mass from the head and neck region of a child raises four differential diagnostic possibilities: teratoma, encephalocele, glioma, and heterotopic brain tissue. We present a review of the literature and discuss the clinical, radiographical, and pathological features of a rare nasopharyngeal brain heterotopia in an infant causing upper airway obstruction.

Thin section, high resolution computed tomographic (CT) scans of the lumbar spine produce images that can show herniated intervertebral discs without intravenous or intrathecal contrast enhancement. With this technique, the diagnosis of posterolateral and midline herniation has been greatly facilitated. This communication reports the use of CT discography in the preoperative evaluation of two patients who were shown at discography and proven at operation to have extreme lateral disc herniations.

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.

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.

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.

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.

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.

High-resolution computed tomography (CT) is superior to other imaging modalities in assessing the extent and degree of spinal fractures. The determination of bone fragments within the spinal canal and the detection of posterior neural arch damage are major advantages offered by computed tomography. The addition of intrathecal contrast allows proper assessment of the oftentimes confusing neurologic picture. Plain roentgenograms of the spine are only the initial diagnostic examinations of spinal fractures. Roentgenograms in conjunction with high-resolution CT, performed with or without intrathecal contrast, provide the best evaluation of thoracolumbar spinal fractures.

Computed tomographic myelography (CTM) is the procedure of choice in patients exhibiting spinal manifestations of neurofibromatosis. Due to the lack of specificity of several of the more important plain spine radiographic findings in this disease, CTM may be necessary to distinguish between surgical and nonsurgical entities. CTM will determine the size, shape, and intraspinal extension of posterior mediastinal neural tumors and separate them from the more common thoracic meningoceles. CTM will likewise elucidate the causes of posterior vertebral body scalloping, distinguishing between dural ectasia and neural tumor. CTM will also frequently demonstrate additional asymptomatic lesions at other levels.

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.