CNS imaging findings associated with Parry-Romberg syndrome and en coup de sabre: correlation to dermatologic and neurologic abnormalities.

INTRODUCTION: Parry-Romberg syndrome (PRS) and en coup de sabre (ECS) are variants of morphea. Although numerous findings on central nervous system (CNS) imaging of PRS and ECS have been reported, the spectrum and frequency of CNS imaging findings and relation to cutaneous and neurologic abnormalities have not been fully characterized. METHODS: We retrospectively reviewed patients younger than 50 years at our institution over a 16-year interval who had clinical diagnosis of PRS and ECS by a skin or facial subspecialist. Two neuroradiologists evaluated available imaging and characterized CNS imaging findings. RESULTS: Eighty-eight patients with PRS or ECS were identified (62 women [70.4 %]; mean age 28.8 years). Of the 43 patients with CNS imaging, 19 (44 %) had abnormal findings. The only finding in 1 of these 19 patients was lateral ventricle asymmetry; of the other 18, findings were bilateral in 11 (61 %), ipsilateral to the side of facial involvement in 6 (33 %), and contralateral in 1 (6 %). Sixteen patients had serial imaging examinations over an average of 632 days; 13 (81 %) had stable imaging findings, and 3 (19 %) had change over time. Of six patients with progressive cutaneous findings, five (83 %) had stable imaging findings over time. Among the 23 patients with clinical neurologic abnormality and imaging, 12 (52 %) had abnormal imaging findings. All seven patients with seizures (100 %) had abnormal imaging studies. CONCLUSIONS: In PRS and ECS, imaging findings often are bilateral and often do not progress, regardless of cutaneous disease activity. Findings are inconsistently associated with clinical abnormalities.

Emerging trends in the volume and format of outside examinations submitted for secondary interpretation.

OBJECTIVE: The purpose of this article is to describe the trends of secondary interpretations, including the total volume and format of cases. MATERIALS AND METHODS: This retrospective study involved all outside neuroradiology examinations submitted for secondary interpretation from November 2006 through December 2010. This practice utilizes consistent criteria and includes all images that cover the brain, neck, and spine. For each month, the total number of outside examinations and their format (i.e., hard-copy film, DICOM CD-ROM, or non-DICOM CD-ROM) were recorded. RESULTS: There was no significant change in the volume of cases (1043 ± 131 cases/month; p = 0.46, two-sided Student t test). There was a significant decrease in the volume of hard-copy films submitted, with the mean number of examinations submitted per month on hard-copy film declining from 297 in 2007 to 57 in 2010 (p < 0.0001, Student t test). This decrease was mirrored by an increase in the mean number of cases submitted on CD-ROM (753 cases/month in 2007 and 1036 cases/month in 2010; p < 0.0001). Although most were submitted in DICOM format, there was almost a doubling of the volume of cases submitted on non-DICOM CD-ROM (mean number of non-DICOM CD-ROMs, nine cases/month in 2007 and 17 cases/month in 2010; p < 0.001). CONCLUSION: There has been a significant decrease in the number of hard-copy films submitted for secondary interpretation. There has been almost a doubling of the volume of cases submitted in non-DICOM formats, which is unfortunate, given the many advantages of the internationally derived DICOM standard, including ease of archiving, standardized display, efficient review, improved interpretation, and quality of patient care.

Frequency of eye deviation in stroke and non-stroke patients undergoing head CT.

BACKGROUND AND PURPOSE: Although conjugate eye deviation (CED) on head CT has been described in patients with acute stroke, the incidence in other patient groups remains unknown. The aim of this study was to determine the frequency of eye deviation on head CT in non-stroke patients compared to patients with acute stroke symptoms. MATERIALS AND METHODS: Three groups of patients were identified retrospectively: emergency department (ED)/inpatients undergoing head CT for non-stroke symptoms (group 1), stroke patients receiving intravenous tPA (group 2), and stroke patients undergoing intra-arterial therapy (group 3). The presence on head CT of CED, lone eye deviation (LED), and skew deviation (SD) and the angle of deviation were recorded. The NIHSS score was recorded for groups 2 and 3. RESULTS: CED was present in 17 (14%) of 120 Group 1 patients, 17 (36%) of 47 group 2 patients, and 28 (50%) of 56 Group 3 patients (p < 0.0001). Mean deviation of CED in groups 1, 2, and 3 was 19(o) (range 7-36(o)), 25(o) (range 6-67(o)), and 27(o) (range 11-56(o)), respectively (p = 0.024). LED was seen in 42 (35%) of group 1, 7 (15%) of Group 2, and 2 (4%) of group 3 patients (p < 0.0001). There was no significant difference in SD among groups (p = 0.37). CED was associated with a higher National Institutes of Health Stroke Scale (NIHSS) score among stroke patients (p = 0.0008). CONCLUSION: CED is common in patients with acute stroke. Such deviation may be seen in non-stroke patients, but less commonly and with lesser degrees of deviation.

Superficial siderosis associated with an iatrogenic posterior fossa dural leak identified on CT cisternography.

Superficial siderosis refers to hemosiderin deposition along the pial surface of the brain and spinal cord. It results from chronic and repetitive low-grade bleeding into the subarachnoid space. Dural tears are a common cause of superficial siderosis. Although such tears typically occur in the spine, dural tears can also occur in the posterior fossa. In many cases, posterior fossa dural tears are iatrogenic, and patients may present with neuroimaging evidence of postoperative pseudomeningoceles. We present a case of superficial siderosis caused by a persistent posterior fossa dural leak. The patient presented with superficial siderosis 30 years after a Chiari I malformation repair. A pinhole-sized dural tear was identified preoperatively using computed tomography cisternography. The dural defect was successfully repaired. An additional small tear that was not seen on imaging was also identified at surgery and successfully repaired.

The Central Dot Sign : A Specific Post-gadolinium Enhancement Feature of Intramedullary Spinal Cord Metastases.

PURPOSE: Peripheral enhancement characteristics on magnetic resonance imaging (MRI), namely the rim and flame signs, are specific for intramedullary spinal cord metastases (ISCM) compared to primary cord masses. The study compared the frequency of a novel finding-the central dot sign-in ISCMs versus primary intramedullary masses. METHODS: In this study 45 patients with 64 ISCMs and 64 control patients with 64 primary intramedullary cord masses were investigated and 2 radiologists blinded to lesion type independently evaluated MR images for the presence of a central dot sign: a punctate focus of enhancement in/near the center of an enhancing intramedullary mass. The frequency of this sign in the two patient groups was compared. RESULTS: A total of 63 enhancing ISCMs in 44 patients and 54 enhancing primary cord masses in 54 patients were included. The central dot sign was identified in 6% (4/63) of enhancing ISCMs in 9% (4/44) of patients and in none (0/54) of the enhancing primary cord masses (p = 0.038, per patient). The specificity for diagnosing ISCMs among spinal cord masses was 100%. The central dot sign was present in the axial plane only in two ISCMs and in the axial and sagittal planes in two ISCMs. The two ISCMs harboring the central dot sign also demonstrated both the previously described rim and flame signs, and two also demonstrated the rim sign alone. CONCLUSION: The central dot sign is not sensitive but highly specific for ISCMs compared to primary spinal cord masses. The rim and/or flame signs may or may not be concurrently present in ISCMs.

e-ASPECTS software improves interobserver agreement and accuracy of interpretation of aspects score.

INTRODUCTION: There is increased interest in the use of artificial intelligence-based (AI) software packages in the evaluation of neuroimaging studies for acute ischemic stroke. We studied whether, compared to standard image interpretation without AI, Brainomix e-ASPECTS software improved interobserver agreement and accuracy in detecting ASPECTS regions affected in anterior circulation LVO. METHODS: We included 60 consecutive patients with anterior circulation LVO who had TICI 3 revascularization within 60 minutes of their baseline CT. A total of 16 readers, including senior neuroradiologists, junior neuroradiologists and vascular neurologists participated. Readers interpreted CT scans on independent workstations and assessed final ASPECTS and evaluated whether each individual ASPECTS region was affected. Two months later, readers again evaluated the CT scans, but with assistance of e-ASPECTS software. We assessed interclass correlation coefficient for total ASPECTS and interobserver agreement with Fleiss' Kappa for each ASPECTS region with and without assistance of the e-ASPECTS. We also assessed accuracy for the readers with and without e-ASPECTS assistance. In our assessment of accuracy, ground truth was the 24 hour CT in this cohort of patients who had prompt and complete revascularization. RESULTS: Interclass correlation coefficient for total ASPECTS without e-ASPECTS assistance was 0.395, indicating fair agreement compared, to 0.574 with e-ASPECTS assistance, indicating good agreement (P < 0.01). There was significant improvement in inter-rater agreement with e-ASPECTS assistance for each individual region with the exception of M6 and caudate. The e-ASPECTS software had higher accuracy than the overall cohort of readers (with and without e-ASPECTS assistance) for every region except the caudate. CONCLUSIONS: Use of Brainomix e-ASPECTS software resulted in significant improvements in inter-rater agreement and accuracy of ASPECTS score evaluation in a large group of neuroradiologists and neurologists. e-ASPECTS software was more predictive of final infarct/ASPECTS than the overall group interpreting the CT scans with and without e-ASPECTS assistance.

Brain Herniation into Arachnoid Granulations: Clinical and Neuroimaging Features.

BACKGROUND/PURPOSE: Brain herniation into presumed arachnoid granulations (BHAG) is an increasingly recognized entity. Though it has previously been described as isointense to brain matter on magnetic resonance imaging (MRI), we have encountered 21 cases in our clinical practice, many of which have signal abnormality in the herniated or adjacent parenchyma. We performed a systematic analysis on these cases to further understand the clinical significance. METHODS: This is a retrospective analysis of cases collected from our clinical MRI practice. Each case was evaluated for location, size, lobe of origin, associated signal abnormality, symptoms, and the presence or absence of intracranial hypertension. RESULTS: Twenty-one cases of BHAG identified in 16 patients. Seven cases (7/21, 33%) demonstrated signal abnormality in the herniated or underlying parenchyma. On serial imaging, the size of herniation either fluctuated (2/10, 20%) or stayed the same (8/10, 80%). The associated signal abnormalities increased (1/5, 20%), decreased (1/5, 20%), or remained stable (3/5, 60%). Four patients (4/16, 25%) had signs/symptoms that could be associated with the BHAG. Ten patients (10/16, 63%) had either imaging findings or clinical signs that could be associated with intracranial hypertension. CONCLUSION: In contrast to previously reported cases, our study demonstrates that BHAG can be associated with MRI signal abnormalities of the herniated and adjacent brain. Symptoms are typically absent, though may be present in a small subset of patients, regardless of the presence of signal change or encephalomalacia of the involved brain. Indirect evidence of intracranial hypertension is present in a majority of patients but completely lacking in others.

The effects of changes in utilization and technological advancements of cross-sectional imaging on radiologist workload.

RATIONALE AND OBJECTIVES: To examine the effect of changes in utilization and advances in cross-sectional imaging on radiologists' workload. MATERIALS AND METHODS: All computed tomography (CT) and magnetic resonance imaging (MRI) examinations performed at a single institution between 1999 and 2010 were identified and associated with the total number of images for each examination. Annual trends in institutional numbers of interpreted examinations and images were translated to changes in daily workload for the individual radiologist by normalizing to the number of dedicated daily CT and MRI work assignments, assuming a 255-day/8-hour work day schedule. Temporal changes in institutional and individual workload were assessed by Sen's slope analysis (Q = median slope) and Mann-Kendall test (Z = Z statistic). RESULTS: From 1999 to 2010, a total of 1,517,149 cross-sectional imaging studies (CT = 994,471; MRI = 522,678) comprising 539,210,581 images (CT = 339,830,947; MRI = 199,379,634) were evaluated at our institution. Total annual cross-sectional studies steadily increased from 84,409 in 1999 to 147,336 in 2010, representing a twofold increase in workload (Q = 6465/year, Z = 4.2, P < .0001). Concomitantly, the number of annual departmental cross-sectional images interpreted increased from 9,294,140 in 1990 to 94,271,551 in 2010, representing a 10-fold increase (Q = 8707876/year, Z = 4.5, P < .0001). Adjusting for staffing changes, the number of images requiring interpretation per minute of every workday per staff radiologist increased from 2.9 in 1999 to 16.1 in 2010 (Q = 1.7/year, Z = 4.3, P < .0001). CONCLUSIONS: Imaging volumes have grown at a disproportionate rate to imaging utilization increases at our institution. The average radiologist interpreting CT or MRI examinations must now interpret one image every 3-4 seconds in an 8-hour workday to meet workload demands.

Traumatic anterior cervical pseudomeningocele causing intracranial hypotension successfully treated with blood patch: case report.

Cervical pseudomeningocele is a rare complication of trauma. It develops when an extradural collection of cerebrospinal fluid (CSF) develops after a dural breach. The authors present the unusual case of a 33-year-old man with progressive headache, neck pain, mental status changes, and cardiopulmonary instability after polytrauma sustained from a motorcycle-versus-deer collision, without improvement during a 5-day hospitalization. Magnetic resonance imaging revealed a collection of CSF anterior to the cervical thecal sac compatible with an anterior cervical pseudomeningocele. A nontargeted epidural blood patch was performed with subsequent resolution of the patient's symptoms. Anterior cervical pseudomeningoceles are usually asymptomatic; however, these lesions can cause orthostatic headaches, neck pain, and cardiopulmonary compromise, as it did in the featured patient. Pseudomeningoceles should be included in the differential diagnosis for posttrauma patients with progressive neurological decline or postural headache, and blood patch may be an effective minimally invasive treatment.

Vertebral body infarct and ventral cauda equina enhancement: two confirmatory findings of acute spinal cord infarct.

Two valuable confirmatory MRI findings of acute spinal cord infarct are highlighted and discussed: concomitant vertebral body infarct and ventral cauda equina nerve root enhancement.

Thyroid acropachy: report of 40 patients treated at a single institution in a 26-year period.

Thyroid acropachy is an extreme manifestation of autoimmune thyroid disease. It presents with digital clubbing, swelling of digits and toes, and periosteal reaction of extremity bones. It is almost always associated with ophthalmopathy and thyroid dermopathy. During a 26-yr period at our institution, of 178 patients with thyroid dermopathy, 40 had acropachy. Clubbing associated with thyroid dermopathy (pretibial myxedema) was seen in 35 patients. Clubbing usually was not a patient complaint and was noted only by clinical observers. Four of eight patients with hand and extremity radiographs had periosteal reaction. Seven had associated extremity and joint pain; this pain was absent at long-term follow-up. Half of the patients required systemic corticosteroid therapy, 53% required transantral or transfrontal orbital decompression for severe ophthalmopathy, and 18% had the elephantiasic form of dermopathy. Cigarette-smoking rates were 81% for women and 75% for men (mean, 28 pack-years). All 13 patients who had thyroid-stimulating Ig measurement had high titers. Long-term follow-up (median, 12.5 yr) revealed that acropachy was not a complaint in follow-up visits or questionnaires. The data suggest that thyroid acropachy is an indicator of severity of ophthalmopathy and dermopathy. It is a source of clinical concern only if dermopathy is persistent and severe.

Dermopathy of Graves' disease (pretibial myxedema): long-term outcome.

Little is known about the long-term outcome of patients with thyroid dermopathy, an extrathyroidal manifestation of Graves' disease. Also, it is not known to what degree treatment promotes remission of the lesions. The present report supplies information on the natural course of mild, untreated and severe, treated thyroid dermopathy. In this study, we report on the outcomes of 178 patients seen at our institution between January 1969 and November 1995 with thyroid dermopathy who were followed up for an average of 7.9 yr. Nonpitting edema was the most prevalent form of dermopathy (43.3%), and the pretibial area was the region most commonly involved (99.4%). The majority of patients with dermopathy had ophthalmopathy (97.0%). Topical corticosteroids were the most commonly used treatment (53.9%). Patients with milder forms of dermopathy (40.4%) did not receive any therapy for dermopathy. Twenty-six percent of the patients experienced complete remission, 24.2% had moderate improvement (partial remission), and 50.0% had no or minimal improvement of their dermopathy at last follow-up. Patients who did not receive therapy experienced a significantly (P = 0.03) higher rate of complete remission (34.7%) than those who received local therapy (18.7%), although the combined complete and partial remission rates were not significantly different for the treated and untreated groups (P = 0.3). However, the treated and untreated groups were not comparable because our practice is to use therapy for more extensive and severe cases. All five cases of elephantiasis were in the treatment group and were less likely to have remission because of the severity of their skin condition. Patients receiving treatment were more likely to have dermatologic consultation and histologic diagnosis (P < 0.001). The beneficial effect of topical corticosteroid therapy on long-term remission rates remains to be determined.

Ventilation tube removal: does treatment affect perforation closure?

OBJECTIVE: The study goal was to determine whether treatment of the tympanic membrane at the time of ventilation tube (VT) removal affects closure of the perforation. STUDY DESIGN: We conducted a retrospective chart review and telephone follow-up of children who underwent VT removal from 1995 through 1998. RESULTS: Among 109 patients (162 ears; 58% male), the mean age at VT removal was 6.7 years. Most VTs (59%) were T-tubes, and most (91%) were removed because of prolonged retention (mean 2.3 years). After VT removal, 111 ears (69%) received treatment, most commonly (44%) with 25% trichloroacetic acid (TCA). At the latest follow-up, 151 of the ears (93%) had healed without additional treatment. Treatment failure occurred more frequently in ears not initially treated with TCA (TCA 3% failure, other treatment 13%, no treatment 8%) and in ears with VTs removed because of otorrhea. CONCLUSIONS: Most perforations healed. TCA may promote closure, but a large randomized clinical trial is needed to eliminate physician bias.

Increasing neuroradiology exam volumes on-call do not result in increased major discrepancies in primary reads performed by residents.

BACKGROUND AND PURPOSE: A common perception is that increased on-call workload leads to increased resident mistakes. To test this, we evaluated whether increased imaging volume has led to increased errors by residents. MATERIALS AND METHODS: A retrospective review was made of all overnight neuroradiology CT exams with a primary resident read from 2006-2010. All studies were over-read by staff neuroradiologists next morning. As the volume is higher on Friday through Sunday nights, weekend studies were examined separately. Discrepancies were classified as either minor or major. "Major" discrepancy was defined as a discrepancy that the staff radiologist felt was significant enough to potentially affect patient care, necessitating a corrected report and phone contact with the ordering physician and documentation. The total number of major discrepancies was recorded by quarter. In addition, the total number of neuroradiology CT studies read overnight on-call was noted. RESULTS: The mean number of cases per night during the weekday increased from 3.0 in 2006 to 5.2 in 2010 (p<0.001). During the weekend, the mean number of cases per night increased from 5.4 in 2006 to 7.6 in 2010 (p<0.001). Despite this increase, the major discrepancy rate decreased from 2.7% in 2006 to 2.3% in 2010 (p=0.34). CONCLUSION: Despite an increase in neuroradiology exam volumes, there continues to be a low major discrepancy rate for primary resident interpretations. While continued surveillance of on-call volumes is crucial to the educational environment, concern of increased major errors should not be used as sole justification to limit autonomy.

Benign fibrous dysplasia on [(11)C]choline PET: a potential mimicker of disease in patients with biochemical recurrence of prostate cancer.

We present the case of a 74-year-old male with biochemical recurrence of prostate cancer who underwent [(11)C]choline PET/CT. The PET/CT demonstrated an intense focus of uptake within the skull base that was initially felt to potentially represent metastatic disease. Subsequent evaluation with MRI and dedicated thin-section CT revealed this area to be benign fibrous dysplasia of the bone. The focal uptake on PET/CT with [(11)C]choline in benign fibrous dysplasia represents a potential mimicker of metastatic disease. Due to recognizing this benign process, our patient was able to avoid systemic treatment and/or focal radiation and was treated with cryotherapy for biopsy-proven local recurrence within the prostate bed. While benign fibrous dysplasia can demonstrate increased radiotracer uptake on other modalities (i.e., bone scintigraphy, FDG PET/CT), its appearance on [(11)C]choline PET/CT has been largely overlooked in the literature. With the increasing use of [(11)C]choline PET/CT for biochemical recurrent prostate cancer evaluation, it is important to understand this potential mimicker of disease.

Intramuscular dirofilariasis mimicking an orbital metastasis in a patient with breast cancer.

We present the unusual case of a 74 year-old female with a history of breast cancer who presented with acute painless orbital swelling and vertical diplopia. MRI revealed a focal enhancing mass within the superior rectus muscle. As the concern for metastatic disease was high, surgical biopsy was performed and revealed an unusual mimicker of metastatic disease, the parasitic infection dirofilariasis.

Diffusion-weighted imaging for cholesteatoma evaluation.

Computed tomography (CT) has long been considered the optimal imaging technique for the detection of cholesteatomas. However, this modality often lacks specificity, particularly in patients with an absence of definite bony erosion or a history of surgical excision. Several investigators have proposed magnetic resonance imaging with diffusion-weighted imaging (DWI) as a means of diagnosing the presence and extent of cholesteatomas, particularly when CT results are equivocal. The rationale for the use of DWI is that cholesteatomas demonstrate restricted diffusion and granulation tissue does not. In this retrospective study, we review our experience with 12 patients who had undergone DWI for evaluation of a mass in the middle ear, mastoid, or petrous apex. Ten of these patients had previously undergone middle ear surgery, 8 for cholesteatoma resection. On DWI, 9 patients demonstrated restricted diffusion. Of these, 8 patients underwent surgical resection, and all were found to have had a cholesteatoma. Of the 3 patients who had not demonstrated restricted diffusion on DWI, 2 did not undergo surgery and the other was found to have only chronic inflammation at surgery. Based on our limited experience, we believe that DWI can be useful in confirming the diagnosis of cholesteatoma. Moreover, it may alter patient management, particularly in patients whose previous tympanoplasty/mastoidectomy does not allow for an adequate clinical inspection of the middle ear cavity.

Hepatitis C-associated osteosclerosis: a case report.

A 38-year-old man presented for evaluation of severe pain in his lower limbs of 16 months' duration. Radiographs showed diffuse bony sclerosis involving the axial and appendicular skeleton with marked cortical thickening in the diaphyseal regions of the long bones. Iliac crest biopsy revealed abundant sclerotic bone. The patient was diagnosed with hepatitis C secondary to intravenous drug use 20 years earlier, and the bony findings and clinical symptoms attributed to hepatitis C-associated osteosclerosis (HCAO). Little is known about the natural history of this disease; however, we discuss the patient's clinical course over 15 years.