Congenital Spinal Cysts: An Update and Review of the Literature.

Congenital spinal cysts are rare and encompass a wide variety of diseases including arachnoid, enterogenous, teratomatous, neurenteric, foregut, bronchogenic, epithelial, ependymal, dermoid, and epidermoid cysts. Here, we elucidate the epidemiology, pathology, pathogenesis, and diagnostic findings of the most common congenital spinal cysts, followed by a discussion of their presentation and treatment options. Differentiating the cause of each lesion is crucial for targeted clinical and surgical management for the patient. Our review describes how arachnoid cysts can be observed, fenestrated, percutaneously drained, or shunted; however, the primary goal for neurenteric, dermoid, and epidermoid cysts is removal. Further, we discuss how patient presentation is dependent on the rate of growth and location of compression on the spinal cord and nerve roots. However, although many of these lesions are discovered incidentally on imaging, the spectrum of possible symptoms include pain, weakness, ataxia, bladder incontinence, and progressive or acute neurologic deficits. We present and review the histology and imaging of a variety of cysts and discuss how although the goal of treatment is resection, the risks of surgery must be considered against the benefits of complete resection in each case.

Functional MRI activation patterns of cerebellum in patients with epilepsy and brain tumors.

Function of cerebellum in control and coordination of motor function has been well established for several years. Recent functional magnetic resonance imaging (MRI) studies reveal activation of cerebellum with memory, speech and language tasks. We hypothesize that during every function in the brain signals are relayed to cerebellum. We seek to analyze cognitive, emotional and social functions of cerebellum in patients with brain tumors and epilepsy utilizing functional Magnetic Resonance Imaging. Fifty-one consecutive adult patients who underwent functional MRI examination were retrospectively analyzed for various activation patterns involving cerebellum. The neuropsychological battery of tasks assessed motor, language, memory, visual and auditory functions. Cognitive ability of all participants was assessed by Montreal cognitive assessment (MOCA). Patterns were analyzed for specific lobes and locations in the cerebellum. We found that simultaneous cerebellar activation is a consistent finding with brain activation during every functional MRI task that we tested except visual task. The patterns of functional MRI cerebellar activation were similar in both patient subgroups and control subjects compared to previously described patterns in normal subjects. Clin. Anat. 32:1053-1060, 2019. © 2019 Wiley Periodicals, Inc.

Differentiation of branchial cleft cysts and malignant cystic adenopathy of pharyngeal origin.

OBJECTIVE: There is an increasing incidence of head and neck cancers that present as neck masses in a nonsmoking nondrinking population. These masses can be confused with benign cystic neck masses. The purpose of this study was to determine imaging criteria to differentiate benign lateral neck cysts from malignant cystic adenopathy. MATERIALS AND METHODS: A retrospective analysis of patients who underwent contrast-enhanced neck CT between July 2003 and July 2011 was performed. Patients were diagnosed with either a branchial cleft cyst or pharyngeal squamous cell cancer. Each examination was reviewed by a neuroradiologist, and, for each cyst or cystic lymph node, the anatomic level in the neck, dimensions, wall thickness, septations, homogeneity, extracapsular spread, calcifications, and fat stranding were recorded. Data analysis was performed using Student t tests and chi-square tests. RESULTS: Twenty-one patients with branchial cleft cysts and 29 patients with squamous cell carcinoma met the inclusion criteria. Significant differences between the groups were found with regard to size, homogeneity, and extracapsular spread. Branchial cleft cysts were found to be larger on the long axis (p < 0.001), short axis (p < 0.001), and height (p < 0.001). They were less likely to have extracapsular spread (p = 0.044) or septations (p = 0.059) and more likely to be homogeneous (p < 0.001). CONCLUSION: Misdiagnosis of malignant cysts in the neck may lead to delay in diagnosis, a violated neck, tumor spillage, and spread. Differences in radiographic criteria can guide clinical decision making in the patient with a neck mass. However, fine-needle aspiration may be necessary to confirm the diagnosis.

Imaging of neonatal brain emergencies: multisequence MRI analysis of pathologic spectrum including diffusion and MR spectroscopy.

The purpose of this pictorial essay is to review the normal neonatal brain MR anatomy and the MR imaging appearances of neonatal brain emergencies and discuss the advantages of individual MR imaging sequences and the clinical implications of utilizing MRI as a problem-solving modality in the neonatal intensive care unit. Here we briefly discuss the normal MR imaging anatomy and myelination pattern and normal MR spectroscopy findings in a neonate. The role of individual MR imaging sequences in evaluating various neonatal abnormalities is being emphasized. For example, the utility of diffusion-weighted imaging for the diagnosis of profound hypoxic-ischemic injury and other forms of hypoxic-ischemic encephalopathies and MR spectroscopy in the diagnosis of metabolic encephalopathies and genetic disorders including aminoacidurias is being presented.

Optimization of patient dose and image quality with z-axis dose modulation for computed tomography (CT) head in acute head trauma and stroke.

The purpose of this study is to retrospectively analyze the effect of z-axis modulation for CT head protocols on patient dose and image quality in patients with acute head trauma and stroke. The study was approved by the Institutional Review Board. We retrospectively evaluated the effect of dose modulation on unenhanced CT head examinations in patients with acute head trauma and stroke. Two series of 100 consecutive studies were reviewed: 100 studies performed without dose modulation, 100 studies performed with z-axis dose modulation. Multidetector 16-section CT was performed sequentially and axial 5-mm-thick slices were obtained from base of skull to vertex. With z-axis dose modulation, the same tube current range was maintained, but a computer algorithm altered the tube current applied to each CT section. For each examination, the weighted volume CT dose index (CTDI (vol)) and dose-length product (DLP) were recorded and noise was measured. Each study was also reviewed for image quality by two independent, blinded readers. The variables (CTDI (vol) and DLP, image quality, and noise) in the two groups were compared by using student t test and Wilcoxon rank-sum test. For unenhanced CT head examinations, the CTDI (vol) and DLP, respectively, were reduced by 35.8% and 35.2%, respectively, by using z-axis dose modulation. Image quality and noise were unaffected by the use of this dose modulation technique (P < 0.004). Utilization of z-axis modulation technique for CT head examination in patients with acute head trauma and stroke offers significant radiation dose reduction while image quality is optimally maintained.

Giant tumefactive perivascular spaces manifesting as chorea bilaterally.

Virchow-Robin (VR) spaces or perivascular spaces (PVSs) of the brain are pial-lined interstitial fluid-filled structures that accompany penetrating arteries and arterioles for a variable distance as they descend into the cerebral substance. VR spaces can be identified on magnetic resonance (MR) images obtained in patients of all ages in many areas of the brain. Infrequently, these become remarkably enlarged, and can assume configurations that may be mistaken for a more clinically significant disease, such as a cystic neoplasm or parasitic infections like cysticercosis. We report the first MR imaging description of a case of giant tumefactive (PVSs) manifesting as chorea bilaterally.

Subtle pathology detection with multidetector row coronal and sagittal CT reformations in acute head trauma.

We sought to analyze retrospectively the advantages of coronal and sagittal reformations obtained with multidetector row computed tomography (CT) in patients with acute head trauma. Multidetector 16-section CT was performed in 200 patients (110 male and 90 female; age range, 3-87 years; mean age, 45 years) with acute head trauma. Scans were performed sequentially, and axial 5-mm-thick slices were obtained from base of skull to vertex. The source data set was reformatted in coronal and sagittal planes, with 2-mm-thick sections at 2-mm intervals. Images were analyzed retrospectively by two independent, blinded readers. The final diagnosis was determined by clinical follow-up. CT imaging abnormalities were detected in 55 out of 200 patients who were scanned for head trauma. Acute traumatic intracranial abnormality was detected on axial scans in 45 patients. Subtle findings were confirmed on coronal and sagittal CT reformations in ten cases, and these were undetected initially on axial CT. Coronal and sagittal reformations confirmed subtle findings in 18.2% (10/55) of the cases (P = 0.001). Indeterminate neuroimaging findings confirmed by coronal and sagittal CT head reformations include tentorial and interhemispheric fissure subdural hemorrhage, subarachnoid hemorrhage, and inferior frontal and temporal lobe contusions. Coronal and sagittal CT head reformations improve the sensitivity and diagnostic confidence in the clinical setting of acute trauma. Overall, coronal and sagittal reformations improved diagnostic confidence and interobserver agreement over axial images alone for visualization of normal structures and in the diagnosis of acute abnormality.

Central nervous system lymphoma characterization by diffusion-weighted imaging and MR spectroscopy.

PURPOSE: The characterization and differentiation of central nervous system (CNS) lymphoma has important diagnostic, therapeutic, and prognostic significance. The purpose of this study is to characterize the diffusion-weighted imaging (DWI) and MR spectroscopic (MRS) findings in CNS lymphoma. MATERIALS AND METHODS: Twenty consecutive patients (male [n= 12], female [n= 8]) with histopathologically proven CNS lymphoma were retrospectively evaluated during this study from July 2005 to April 2007. Patients included immunocompromised (n= 9) and immunocompetent (n= 11) individuals. MR Imaging (pretreatment n= 13), pre- and post-treatment (n= 7) included DWI (n= 20) (b = 1000s/mm2) and ADC (apparent diffusion coefficient) maps of all patients. MRS was performed (n= 10) with PRESS (point-resolved spectroscopy) sequence (multivoxel n= 8, single voxel n= 2) with a TE of 144 msec. All patients were histopathologically confirmed to have lymphoma by biopsy. RESULTS: Areas of restricted diffusion were observed in 90 % (n= 18/20) on pretreatment scans. The diffusion restriction was variable on post-treatment scans. Median metabolite ratios in 10 patients were Cho/Cr- 2.12, NAA/Cho - .49, and NAA/Cr - 1.64. Presence of lactate or lipid was noted in 90 % (n= 9/10). Sites of lesion location were subcortical white matter (n= 6), basal ganglia (n= 4), corpus callosum (n= 3), extra-axial space including cavernous sinus (n= 5), cerebellum (n= 1), and lateral ventricle (n= 1). CONCLUSION: Restricted diffusion is a consistent imaging finding in CNS lymphoma in immunocompetent patients. Spectroscopy is helpful in initial imaging diagnosis and post-treatment surveillance. These lesions are usually paraventricular in location. MR imaging appearances differ among immunocompetent and immunosuppressed individuals in most cases.

CT of colon cancer metastases to the liver using modified RECIST criteria: determining the ideal number of target lesions to measure.

OBJECTIVE: We sought to define the ideal number of target lesions to be measured to assess disease response in patients undergoing chemotherapy for colon cancer metastases to the liver. MATERIALS AND METHODS: Thirty consecutive patients were recruited for this study. Patients were part of a multisite, randomized, double-arm, phase 3 clinical trial involving chemotherapy with an investigational drug for metastatic colon cancer. Patients were recruited from U.S. and international sites. Institutional review board approval was obtained, and informed consent was obtained from all patients. Our study included CT measurements of hepatic metastases. All patients (n = 30) had a minimum of five target lesions in the liver. Target-lesion size was defined by Response Evaluation Criteria in Solid Tumors (RECIST) criteria. We calculated the patient response at 2 months and at 6 months (complete response, partial response, stable disease, and progressive disease) using RECIST. Patient response was calculated based on the percentage increase or decrease at 2 and 6 months in the greatest diameter of the single largest lesion, two large lesions, three large lesions, four lesions, and five lesions, respectively. The concordance between five-target-lesion measurement and lesser numbers of lesions was analyzed using kappa statistics (StatView, 5.0). RESULTS: In 93.33% of patients (n = 28/30), there was agreement on patient response irrespective of the number of measurements made on CT. Of these 30 patients, 47% had a partial response (n = 14/30), 43% had stable disease (n = 13/30), and 10% had progressive disease at 2 months (n = 3/30). At 6 months, 43% had a partial response (n = 13/30), 47% had stable disease (n = 14/30), and 10% had progressive disease (n = 3/30). Agreement in response evaluation between lesion groups for multiple measurements was high, with values of 1.0 for multiple-lesion measurements and 0.88 for single-lesion measurements at 2 months. The concordance values were the same at 6 months. CONCLUSION: In the majority of patients with hepatic metastases of colorectal cancer, measuring the maximal diameter of the single largest lesion yielded the same treatment-response classification as measuring up to five target lesions. This result suggests that it may be possible to reduce the number of lesions measured in clinical trials.

MR imaging of abdominopelvic involvement in neurofibromatosis type 1: a review of 43 patients.

BACKGROUND: Plexiform neurofibromas are a frequent complication of neurofibromatosis type 1. This article discusses MR imaging findings and distribution of plexiform neurofibromas in the abdomen and pelvis. OBJECTIVE: To define the most prevalent patterns of involvement and MR imaging findings in abdominopelvic neurofibromatosis type 1. MATERIALS AND METHODS: We reviewed the MR appearance of abdominopelvic lesions in 23 male and 20 female patients (median age: 16 years) with type 1 neurofibromatosis. The patients were part of a multi-institutional study of 300 patients. Imaging included coronal or sagittal, and axial short tau inversion recovery images. RESULTS: The most common abdominopelvic involvement was in the abdominopelvic wall (n=28, 65%) and lumbosacral plexus (n=27, 63%). Retroperitoneal involvement was frequent (n=15, 35%). Lesions were less often intraperitoneal (21%) (P=0.001). Pelvic disease (n=27, 63%), neural canal involvement (n=18, 42%), and hydronephrosis (n=4, 9%) were also noted. Target-like appearance of plexiform lesions was noted in more than half the patients. CONCLUSION: Abdominopelvic involvement in neurofibromatosis type 1 is primarily extraperitoneal. Although lesions are most prevalent in the abdominopelvic wall and lumbosacral plexus, retroperitoneal and pelvic involvement is common and usually affects important organs. MR imaging added information in the initial and follow-up clinical evaluation of these patients.

Sonographic appearance of a congenital parotid gland hemangiolymphangioma simulating malignancy in an infant.

Congenital hemangiolymphangioma, also called mixed angioma, is a benign tumor that very rarely occurs in the parotid gland. We present a rare case of hemangiolymphangioma of the parotid gland in a 4-month-old boy whose clinical and radiologic presentation simulated malignancy. Gray-scale and color Doppler sonography revealed an enlarged left parotid gland and inhomogeneous hypoechoic and hyperechoic areas scattered throughout the gland. Mild internal vascularity was noted on color Doppler sonographic examination. CT revealed a predominantly fatty mass involving the superficial lobe of the parotid gland. The results of fine-needle aspiration cytology were inconclusive, and total parotidectomy was performed. Histopathologic examination of surgical specimens confirmed a diagnosis of hemangio lymphangioma. The patient recovered well and was free of recurrence at the 6-month follow-up visit. To our knowledge, this case report is the first to describe the findings of congenital hemangiolymphangioma of the parotid gland on sonography and CT. This rare diagnosis should be considered in neonates and infants presenting with a rapidly growing parotid gland tumor suggesting malignancy. Histopathologic examination is necessary to confirm the diagnosis.