The CT scout view: does it need to be routinely reviewed as part of the CT interpretation?

OBJECTIVE: The objective of our study was to determine whether the CT scout view should be routinely reviewed by comparing diagnostic information on the scout view with that provided by the correlative CT study. MATERIALS AND METHODS: Two radiologists blinded to history and CT findings reviewed retrospectively 2032 scout views. All cases with major findings (defined as any abnormality that would prompt additional diagnostic tests or require management) were correlated with the CT study, other imaging study, or medical record when necessary by a third radiologist to determine the validity of the scout view finding and whether the finding was identifiable on the current CT study. RESULTS: Major findings were identified in 257 (13%, reader 1) and 436 (23%, reader 2) of cases. Most major findings were confirmed (69-78%) or refuted (13-16%) by the CT study. However, 15 (6%, reader 1) and 48 (11%, reader 2) of the major findings were not included in the CT FOV, of which five (2%, reader 1) and 21 (5%, reader 2) constituted a missed pathologic finding. The most common one was cardiomegaly detected on a nonchest CT scout view. Additional pathologic findings included fracture, metastasis, avascular necrosis or subluxation of the humeral head, dilated bowel, and thoracic aortic dilatation. The most common false-positive finding was cardiomegaly. CONCLUSION: In a small percentage of cases, review of the CT scout view will disclose significant pathologic findings not included in the CT FOV. The results of this study support the routine inspection of the scout view, especially for the detection of pathologic findings in anatomic regions not imaged by CT.

Functional müllerian tissue within the conus medullaris generating cyclical neurological morbidity in an otherwise healthy female.

PURPOSE: Endometriosis is a common disease; however, ectopic müllerian tissue within the spine is a rare entity with the potential for producing significant neurological compromise. There are several postulated etiologies for this phenomenon, and only a few case reports are available in the world literature. Knowledge of this rare phenomenon is of paramount importance, since early diagnosis can lead to lessened neurological morbidity. METHODS: In this manuscript, we present a case report, discuss gynecological and neurosurgical perspectives relating to the treatment strategies for managing this entity, and propose an alternative explanation for such an occurrence from a neurogenetic standpoint. RESULTS: We present a case of spinal müllerianosis within the conus medullaris which was managed symptomatically for several years with an intracystic drain and subcutaneous reservoir. Over the years, it became clear that there was a cyclical presentation to her clinical malady, which at times was severe. Ultimately, she required surgical resection which aided in her diagnosis and subsequent treatment. CONCLUSION: Intraspinal müllerianosis is a rare location for an otherwise common disease in women and has the potential to create significant neurological morbidity by creating a mass lesion. Although the exact etiology remains unclear, the histogenic theories of embryologic origin appear most plausible. Treatment strategies for this condition may include hormonal therapy, obstetrical surgery, or open spinal surgery. This unusual and poorly understood disease should be considered in the differential diagnosis for intraspinal lesions presenting with hemorrhage in the clinical context of cyclical neurological symptoms.

The iPad as a mobile device for CT display and interpretation: diagnostic accuracy for identification of pulmonary embolism.

Recent software developments enable interactive, real-time axial, 2D and 3D CT display on an iPad by cloud computing from a server for remote rendering. The purpose of this study was to compare radiologists' interpretative performance on the iPad to interpretation on the conventional picture archive and communication system (PACS). Fifty de-identified contrast-enhanced CT exams performed for suspected pulmonary embolism were compiled as an educational tool to prepare our residents for night call. Two junior radiology attendings blindly interpreted the cases twice, one reader used the PACS first, and the other interpreted on the iPad first. After an interval of at least 2 weeks, the cases were reinterpreted in different order using the other display technique. Sensitivity, specificity, and accuracy for identification of pulmonary embolism were compared for each interpretation method. Pulmonary embolism was present in 25 patients, ranging from main pulmonary artery to subsegmental thrombi. Both readers interpreted 98 % of cases correctly regardless of display platform. There was no significant difference in sensitivity (98 vs 100 %, p = 1.0), specificity (98 vs 96 %, p = 1.0), or accuracy (98 vs 98 %, p = 1.0) for interpretation with the iPad vs the PACS, respectively. CT interpretation on an iPad enabled accurate identification of pulmonary embolism, equivalent to display on the PACS. This mobile device has the potential to expand radiologists' availability for consultation and expedite emergency patient management.

Gastric pneumatosis: the role of CT in diagnosis and patient management.

Gastric pneumatosis is rare, with causes ranging from benign to lethal. The purpose of this pictorial essay is to present a series of cases of gastric pneumatosis, review the causes, and demonstrate how computed tomography (CT) can help guide management. A range of primary gastric pathology can cause air in the wall of the stomach. However, gastric pneumatosis may reflect intraabdominal pathology arising from other hollow viscera, with indicators of the extragastric etiology on CT.

Torsional strength estimates of femoral diaphyses with endosteal lytic lesions: dual-energy X-ray absorptiometry study.

Pathologic fracture is a significant problem for individuals with metastatic bone disease. Current guidelines for prophylactic internal fixation are neither reliable nor easily applied. The purpose of this study was to validate dual-energy X-ray absorptiometry (DXA) as an accurate method for estimating torsional bone strength of diaphyseal bone with endosteal lytic lesions. Endosteal lesions of varying sizes were simulated in the diaphyses of 12 adult cadaveric femurs. Unaltered contralateral femurs served as matched controls. Machined lesions ranged from 3 to 6.5 cm in length, 1 to 3 cm in width, 15 to 48 cm(2) in elliptical area, with 10% to 100% removal of the cortical thickness. Morphology and density data obtained from DXA images were used to estimate torsional strength. All femora were mechanically tested to failure in torsion. Physically measured torsional strength was not significantly correlated to lesion elliptical area (r = 0.542, p > 0.05) or percentage cortical thickness removed (r = 0.257, p > 0.05). Measured torsional strength was significantly correlated to DXA-based torsional strength estimates (r = 0.855, p < 0.01). Lesion size alone did not correlate with the strength of bones with simulated endosteal lytic lesions. In contrast, calculations based on DXA (morphology, density) did correlate with torsional strength. This is the first step in the development of a DXA-based tool for objectively estimating bone strength in the presence of endosteal lytic lesions.

Improved demonstration of cartilage narrowing in the knee joint using standing PA flexed radiographs.

OBJECTIVE: To compare standing PA flexed (SPAF) knee radiographs of the knees with standing full-extension AP(SAP) radiographs for demonstration of narrowing of the articular cartilage of the knee joint and the presence and size of osteophytes and to determine if sclerosis is a predictor of the severity of joint space narrowing. DESIGN: 220 knees in 110 consecutive patients visiting the orthopaedic clinic with knee pain and having both SPAF radiographs and SAP radiographs at the same visit were evaluated by a musculoskeletal radiologist for cartilage narrowing in the knee joint using a scale 0-3 with 0= normal and 3= bone on bone. Osteophytes were also graded 0-3 and sclerosis as present or absent. PATIENTS: The subjects were patients of one of the authors (C.A.J) who ordered both types of radiographs on most of his patients. RESULTS: In 47% of knees the SPAF radiograph showed narrowing more severe than the SAP radiograph. In 5% the SAP view showed narrowing more severe than the SPAF view. In the medial compartment the SPAF view showed significantly larger osteophytes than the SAP view. The osteophyte size difference was not significant in the lateral compartment. If sclerosis was present on the AP view, there was a greater than 80% chance that the SPAF view would show greater narrowing. CONCLUSION: The SPAF radiograph frequently shows more cartilage narrowing in the knee joint than does the SAP view. It is valuable for routine use or when the clinical severity of arthritis in the knee joint seems to be greater than that demonstrated on the AP standing view. Sclerosis on the SAP view makes it especially likely that the SPAF view will show greater cartilage narrowing.

Retained surgical item identification on imaging studies: a training module for radiology residents.

PURPOSE: Many hospitals experience one or more retained surgical item events per year, with risk of patient morbidity and medicolegal consequences. We hypothesized that the confidence and performance of the radiologist would be enhanced by prior training in retained surgical item detection and by prior exposure to commonly employed surgical instruments and devices. METHODS: A training module for radiology residents was created through literature review, expert consultation, and imaging of commonly employed surgical instruments and devices. A survey assessing resident command of background knowledge, policy, and image-based retained surgical item questions was created. Additionally resident confidence for hospital policy and retained surgical item identification was assessed. A pre-module survey and confidence questionnaire were administered to first- through fourth- year residents. For one month, the training module was available online for independent review. Subsequently, a post-module survey and confidence questionnaire were completed by participants. T tests were performed to evaluate pre- and posttest means for survey performance and confidence questions. RESULTS: Mean post-module survey performance significantly improved compared with pre-module performance. Mean confidence levels for ability to incidentally identify a retained surgical item on a radiograph obtained for another indication and current understanding of the institution's policy regarding retained surgical items were also significantly increased. CONCLUSION: The knowledge base, diagnostic performance, and confidence of radiology residents were significantly enhanced by online teaching module training in retained surgical item detection.

Clinical and radiographic outcomes following traumatic Grade 3 and 4 carotid artery injuries: a 10-year retrospective analysis from a Level 1 trauma center. The Parkland Carotid and Vertebral Artery Injury Survey.

OBJECT: Screening, management, and follow-up of Grade 3 and 4 blunt carotid artery injuries (BCAIs) remain controversial. These high-grade BCAIs were analyzed to define their natural history and establish a rational management plan based on lesion progression and cerebral infarction. METHODS: A retrospective review of a prospectively maintained database of all blunt traumatic carotid and vertebral artery injuries from August 2003 to April 2013 was performed, and Grade 3 and 4 BCAIs were identified. The authors define Grade 3 injuries as stenosis of the vessel greater than 50%, or the development of a pseudoaneurysm, and Grade 4 injuries as complete vessel occlusion. Demographic information, imaging findings, number of images obtained per individual, length of radiographic follow-up examination, radiographic outcome at end of follow-up period, treatment(s), and documentation of ischemic stroke or transient ischemic attack (TIA) were recorded. RESULTS: Fifty-three Grade 3 BCAIs in 44 patients and 5 Grade 4 BCAIs in 5 patients were identified and had available follow-up information. The mean follow-up duration for Grade 3 BCAIs was 113 days, and the mean follow-up for Grade 4 BCAIs was 78 days. Final imaging of Grade 3 BCAIs showed that 53% of cases were radiographically stable, 11% had resolved, and 11% were improved, whereas 25% had radiographically worsened. In terms of treatment, 75% of patients received aspirin (ASA) alone, 5% received various medications, and 2% received no treatment. Eighteen percent of the patients in the Grade 3 BCAI group underwent endovascular intervention, and in all of these cases, treatment with ASA was continued after the procedure. Final imaging of the Grade 4 BCAIs showed that 60% remained stable (with persistent occlusion), whereas the remaining arteries improved (with recanalization of the vessel). All patients in the Grade 4 BCAI follow-up group were treated with ASA, although in 1 patient treatment was transitioned to Coumadin. There were 3 cases of cerebral infarction that appeared to be related to Grade 3 BCAIs (7% of 44 patients in the Grade 3 group), and 1 case of stroke that appeared to be related to a Grade 4 BCAI. All identified cases of stroke developed soon after hospital admission. CONCLUSIONS: Although the posttraumatic cerebral infarction rate may be overestimated, the results of this study suggest that the Grade 3 and 4 BCAIs carry the highest stroke risk of the blunt cerebrovascular injuries, and those infarctions were identified on or shortly after hospital admission. Despite a 40% recanalization rate in the Grade 4 BCAI group and an 89% rate of persistent pseudoaneurysm in the Grade 3 BCAI group, follow-up imaging showed progressive worsening without radiographic improvement in only a small number of patients, and these findings alone did not correlate with adverse clinical outcome. Follow-up protocols may require amending; however, further prospective studies are needed to make conclusive changes as they relate to management.

Clinical and radiographic outcomes following traumatic Grade 1 and 2 carotid artery injuries: a 10-year retrospective analysis from a Level I trauma center. The Parkland Carotid and Vertebral Artery Injury Survey.

OBJECT: Proper screening, management, and follow-up of Grade 1 and 2 blunt carotid artery injuries (BCIs) remains controversial. These low-grade BCIs were analyzed to define their natural history and establish a rational management plan based on lesion progression and cerebral infarction. METHODS: A retrospective review of a prospectively maintained database of all blunt traumatic carotid and vertebral artery injuries treated between August 2003 and April 2013 was performed and Grade 1 and 2 BCIs were identified. Grade 1 injuries are defined as a vessel lumen stenosis of less than 25%, and Grade 2 injuries are defined as a stenosis of the vessel lumen between 25% and 50%. Demographic information, radiographic imaging, number of imaging sessions performed per individual, length of radiographic follow-up, radiographic outcome at end of follow-up, treatment(s) provided, and documentation of ischemic stroke or transient ischemic attack were recorded. RESULTS: One hundred seventeen Grade 1 and 2 BCIs in 100 patients were identified and available for follow-up. The mean follow-up duration was 60 days. Final imaging of Grade 1 and 2 BCIs demonstrated that 64% of cases had resolved, 13% of cases were radiographically stable, and 9% were improved, whereas 14% radiographically worsened. Of the treatments received, 54% of cases were treated with acetylsalicylic acid (ASA), 31% received no treatment, and 15% received various medications and treatments, including endovascular stenting. There was 1 cerebral infarction that was thought to be related to bilateral Grade 2 BCI, which developed soon after hospital admission. CONCLUSIONS: The majority of Grade 1 and 2 BCIs remained stable or improved at final follow-up. Despite a 14% rate of radiographic worsening in the Grade 1 and 2 BCIs cohort, there were no adverse clinical outcomes associated with these radiographic changes. The stroke rate was 1% in this low-grade BCIs cohort, which may be an overestimate. The use of ASA or other antiplatelet or anticoagulant medications in these low-grade BCIs did not appear to correlate with radiographic injury stability, nor with a decreased rate of cerebral infarction. Although these data suggest that these Grade 1 and 2 BCIs may require less intensive radiographic follow-up, future prospective studies are needed to make conclusive changes related to treatment and management.

Clinical and radiological outcomes following traumatic Grade 3 and 4 vertebral artery injuries: a 10-year retrospective analysis from a Level I trauma center. The Parkland Carotid and Vertebral Artery Injury Survey.

OBJECT: Grade 3 and 4 blunt vertebral artery (VA) injuries may carry a different natural course from that of lower-grade blunt VA injuries. Proper screening, management, and follow-up of these injuries remain controversial. Grade 3 and 4 blunt VA injuries were analyzed to define their natural history and establish a rational management plan based on lesion progression and cerebral infarction. METHODS: A retrospective review of a prospectively maintained database of all blunt traumatic carotid and vertebral artery injuries from August 2003 to April 2013 was performed, and Grade 3 and 4 blunt VA injuries were identified. Grade 3 injuries were defined as stenosis of the vessel greater than 50% or the development of a pseudoaneurysm, and Grade 4 injuries were defined as complete vessel occlusion. Demographic information, radiographic imaging findings, number of imaging sessions performed per individual, length of radiographic follow-up, radiographic outcome at end of follow-up, treatment(s) provided, and documentation of ischemic stroke or transient ischemic attack were recorded. RESULTS: A total of 79 high-grade (Grade 3 and 4) blunt VA injuries in 67 patients were identified. Fifty-nine patients with 66 high-grade blunt VA injuries were available for follow-up. There were 17 patients with 23 Grade 3 injuries and 42 patients with 43 Grade 4 injuries. The mean follow-up duration was 58 days for Grade 3 and 67 days for Grade 4 blunt VA injuries. Repeat imaging of Grade 3 blunt VA injuries showed that 39% of injuries were radiographically stable, 43% resolved, and 13% improved, while 1 injury radiographically worsened. Repeat imaging of the Grade 4 blunt VA injuries showed that 65% of injuries were radiographically stable (persistent occlusion), 30% improved (recanalization of the vessel), and in 2 cases (5%) the injury resolved. All Grade 3 injuries that were treated were managed with aspirin or clopidogrel alone, as were the majority of Grade 4 injuries. There were 3 cerebral infarctions thought to be related to Grade 4 blunt VA injuries, which were likely present on admission. All 3 of these patients died at a mean of 13.7 days after hospital admission. No cerebral infarctions directly related to Grade 3 blunt VA injuries were identified. CONCLUSIONS: The majority of high-grade blunt VA injuries remain stable or are improved at final follow-up. Despite a 4% rate of radiographic worsening in the Grade 3 blunt VA injury group and a 35% recanalization rate in the Grade 4 blunt VA injury group, there were no adverse clinical outcomes associated with these radiographic changes. No cerebral infarctions were noted in the Grade 3 group. A 7% stroke rate was identified in the Grade 4 blunt VA injury group; however, this was confined to the immediate postinjury period and was associated with 100% mortality. While these data suggest that these high-grade vertebral artery injuries may require less intensive radiographic follow-up, future prospective studies are needed to make conclusive changes related to treatment and management.

Hormonal Therapy of Prostatic Cancer.

The principle goal of hormonal therapy in the treatment of prostatic cancer, as Huggins suggested in 1941, is the suppression of androgenic stimuli. Consequently, the treatment of advanced prostatic cancer has consisted of orchiectomy, estrogen administration, antiandrogen therapy, adrenalectomy or hypophysectomy, or a combination of some of these. Although the three VACURG studies are subject to several valid criticisms, they provide the best available information to date. In summary, these studies report 1) patients with low stage disease who are treated with estrogen (diethylstilbestrol 5 mg/day) have a higher death rate, mainly cardiovascular, than men not receiving estrogen and 2) in patients with high stage disease, delayed hormonal therapy is as effective as early hormonal therapy. Castration appears to be as effective as treatment with estrogens or a combination of the two and does not evoke the untoward side-effects of estrogen administration. Although subjective improvement has been observed following adrenal or pituitary ablation, the duration of response is usually short, and consequently these procedures are used infrequently now. Experience with the use of antiandrogens is even more limited. Efforts must continue to develop means of predicting hormonal responsiveness. If receptor measurements prove to be an accurate means for predicting the hormonal responsiveness of prostatic cancer, as they have in breast cancer, then our current plan of treatment will need modification. In those men who are unlikely to respond to hormonal therapy, early chemotherapy should be instituted.

Chemotherapy Programs of the National Prostatic Cancer Project (NPCP).

Results of the first nationally randomized trial of the National Prostatic Cancer Project revealed a demonstrable advantage for chemotherapy in the management of advanced disease (Stage D in relapse from endocrine therapy). Both cyclophosphamide and 5-Fluorouracil showed improved activity over standard therapy. A second trial for patients previously irradiated, with less tolerance to myelosuppressive agents, revealed an advantage for estramustine phosphate and streptozotocin over standard therapy. Subsequently completed trials have revealed activity for prednimustine and imidazole carboxamide (DTIC). Trials currently underway for newly-diagnosed Stage D and for Stage D disease clinically stable to diethylstilbestrol (DES) show promising activity for DES combined with cyclophosphamide. Current trials with single agents in advanced disease are comparing methyl-CCNU and hydroxyurea with cyclophosphamide; another is evaluating estramustine phosphate and vincristine alone and in combination. The use of chemotherapy in earlier staged patients as adjuvants to definitive surgery or irradiation is underway in two clinical trials, where the effect of cyclophosphamide and estramustine phosphate as long-term therapies is compared with no additional treatment.

Use of phase imaging in atomic force microscopy for measurement of viscoelastic contrast in polymer nanocomposites and molecularly thick lubricant films.

Phase contrast microscopy, using an atomic force microscope, is used to detect and quantify changes in composition across polymer nanocomposites and molecularly thick lubricated surfaces. The technique takes advantage of the contrast in viscoelastic (viscous energy dissipation) properties of the different materials across the surface. Some materials, especially polymers, are found to display viscoelastic behavior. For such materials, the strain response lags the stress by a phase angle that is characteristic of the material. In tapping (or intermittent contact) mode, phase angle contrast is found to be highly dependent on vibration amplitude and mean tip-to-sample distance (setpoint). Phase angle contrast seems to be a stronger function of viscoelastic properties at relatively high vibration amplitude and low mean tip-to-sample distance. In this regime the effects of sample deformation, and thus viscoelastic properties, are dominant. In these contrast images, low phase angle corresponds to materials with low viscoelastic properties. This technique was used to find fairly reproducible phase angle contrast for polyethylene terephthalate (PET) films with embedded ceramic particles, metal particle (MP) magnetic tape, and Si(100) with a nonuniform Z-15 lubricant film. Very little correlation is found between phase angle images and friction force images for PET films with embedded ceramic particles and MP tape; phase angle images give information that cannot be obtained from topography or friction images. A numerical vibration model verifies that viscoelastic properties are dominant for high vibration amplitude and low mean tip-to-sample distance. For these conditions, the model also verifies that low phase angle corresponds to low viscoelastic properties.

A unifying theory for the multifactorial origin of cerebellar tonsillar herniation and hydrocephalus in osteopetrosis.

OBJECT: Osteopetrosis is a rare congenital metabolic bone disease. There are very few reports in the literature associating cerebellar tonsillar herniation (CTH) and hydrocephalus requiring neurosurgical attention. The authors present cases of osteopetrosis requiring neurosurgical intervention from their practice and offer a detailed account of the literature. METHODS: A retrospective review was conducted at the authors' institution, and all children with osteopetrosis requiring neurosurgical attention were identified. Medical charts and radiographic studies were reviewed. Data including age at presentation, sex, symptoms at presentation, age at follow-up, the presence of any neurological comorbidities, and surgical procedures performed were recorded. RESULTS: Four patients were identified as having osteopetrosis requiring neurosurgical attention at the authors' institution between January 1, 2005, and January 1, 2014. There were 3 females and 1 male with an average age at presentation of 11.1 years; patients were observed for a mean of 4.4 years. All of the patients were identified as harboring jugular foraminal stenosis and CTH. Seventy-five percent of these patients developed hydrocephalus, and in those cases a triventricular pattern of dilation was noted. One patient developed syringomyelia. Three of the 4 patients underwent neurosurgical procedures. Cerebrospinal fluid diversion was performed in 2 patients via a ventriculoperitoneal shunt in one case and an endoscopic third ventriculostomy (ETV) in the other. The former patient required a proximal revision at 2 years for bony overgrowth at the site of the bur hole. Two patients underwent a suboccipital decompression. In patients undergoing CSF diversion, there was improvement in ventricle size. CONCLUSIONS: Variable degrees of hindbrain crowding and/or CTH are mentioned throughout the literature, suggesting that this entity is nearly always present in this patient population. The progressive triventricular hydrocephalus seen in these cases results from a complex combination of both communicating and noncommunicating pathology, which may depend on the type of osteopetrosis, age at presentation, and the presence and degree of venous collateralization, and it appears that the hydrocephalus is more prevalent and more likely to be treated in infants and in the younger, school-aged population. The acquired hindbrain fullness in conjunction with the triventricular pattern of hydrocephalus has kept the authors enthusiastic regarding the use of ETV in these complicated cases.

Clinical and radiological outcomes following traumatic Grade 1 and 2 vertebral artery injuries: a 10-year retrospective analysis from a Level 1 trauma center.

OBJECT: Screening of blunt vertebral artery (VA) injuries has increased since research has shown that they occur at a higher incidence than originally reported. Grade 1 and 2 injuries are the most common form of blunt VA injury. Proper screening, management, and follow-up of these injuries remain controversial. In this report, imaging, progression, treatment, and outcomes of Grade 1 and 2 blunt VA injuries were analyzed to better define their natural history and to establish a rational management plan based upon their risk of progression and cerebral infarct. METHODS: A retrospective review of all blunt traumatic carotid artery and VA injuries from December 2003 to April 2013 was performed. For the purposes of this report, focus was given to Grade 1 and 2 VA injuries. Grade 1 injuries were defined as a vessel lumen stenosis of less than 25%, and Grade 2 injuries were defined as vessel lumen stenosis between 25% and 50%. Demographic information, radiological imaging, number of images performed per individual, length of radiological follow-up, radiological outcome at the end of follow-up, treatment provided, and documentation of stroke or transient ischemic attack were recorded. RESULTS: One hundred eighty-seven Grade 1 and 2 VA injuries in 143 patients were identified. Of these 143 patients, 120 with 152 Grade 1 or 2 blunt VA injuries were available for follow-up. The mean duration of follow-up was 40 days. Repeat imaging showed that 148 (97.4%) Grade 1 or 2 blunt VA injuries were stable, improved, or resolved on final follow-up imaging. Seventy-nine patients (66%) were treated with aspirin, whereas 35 patients (29%) received no treatment. The remaining patients were treated with other antiplatelet agents or anticoagulant medication. Neuroimaging demonstrated 2 cases (1.7%) with posterior circulation infarcts that were believed to be related to their blunt VA injuries, both of which occurred during the initial hospitalization and within the first 4 days after injury. CONCLUSIONS: Although follow-up imaging showed progressive worsening without radiological improvement in only a small number of patients with low-grade blunt VA injuries, these findings did not correlate with adverse clinical outcome. The posttraumatic cerebral infarction rate of 1.7% may be overestimated, and the use of acetylsalicylic acid or other antiplatelet or anticoagulant medication did not correlate with radiological changes or rate of cerebral infarction. While these data suggest the possibility that these low-grade VA injuries may not require treatment or follow-up, future prospective studies are needed to make conclusive changes related to management.

Assessment of common nonsteroidal anti-inflammatory medications by whole blood aggregometry: a clinical evaluation for the perioperative setting.

OBJECTIVE: To help define the perioperative risk related to commonly used non-aspirin NSAIDs with whole blood platelet aggregometry. METHODS: Twelve healthy volunteers were recruited. Two cyclooxygenase (COX)-1 inhibitors (ibuprofen and naproxen) and two COX-2 inhibitors (meloxicam and celecoxib) were administered, and daily whole blood platelet aggregometry studies were obtained until studies showed no platelet inhibition. Aspirin was studied at the conclusion of the study. RESULTS: Ibuprofen had no inhibitory effect on platelet aggregation in all women and no inhibitory effect in 83% of men at 24 hours. All platelet function had returned to normal at 48 hours. The inhibitory effect of naproxen on platelets was absent at 48 hours in 83% of the women and 50% of men. By 72 hours all platelet studies had returned to normal. Meloxicam and celecoxib did not cause any overall inhibitory effect on platelet aggregation. CONCLUSIONS: Ibuprofen and naproxen have a mild inhibitory effect on platelet aggregation compared with aspirin and this effect is undetectable by 48 hours and 72 hours, respectively. Meloxicam and celecoxib show essentially no inhibitory effect on platelet aggregation. These findings suggest that there is little bleeding risk related to platelet aggregation at 24 hours in patients who take COX-2 inhibitors and at 72 hours for those who take COX-1 inhibitor medications.

The Parkland Protocol's modified Berne-Norwood criteria predict two tiers of risk for traumatic brain injury progression.

As a basis for venous thromboembolism (VTE) prophylaxis after traumatic brain injury (TBI), we have previously published an algorithm known as the Parkland Protocol. Patients are classified by risk for spontaneous progression of hemorrhage with chemoprophylaxis regimens tailored to each tier. We sought to validate this schema. In our algorithm, patients with any of the following are classified "low risk" for spontaneous progression: subdural hemorrhage ≤8 mm thick; epidural hemorrhage ≤8 mm thick; contusions ≤20 mm in diameter; a single contusion per lobe; any amount of subarachnoid hemorrhage; or any amount of intraventricular hemorrhage. Patients with any injury exceeding these are "moderate risk" for progression, and any patient receiving a monitor or craniotomy is "high risk." From February 2010 to November 2012, TBI patients were entered into a dedicated database tracking injury types and sizes, risk category at presentation, and progression on subsequent computed tomgraphies (CTs). The cohort (n=414) was classified as low risk (n=200), moderate risk (n=75), or high risk (n=139) after first CT. After repeat CT scan, radiographic progression was noted in 27% of low-risk, 53% of moderate-risk, and 58% of high-risk subjects. Omnibus analysis of variance test for differences in progression rates was highly significant (p<0.0001). Tukey's post-hoc test showed the low-risk progression rate to be significantly different than both the moderate- and high-risk arms; no difference was noted between the moderate- and high-risk arms themselves. These criteria are a valid tool for classifying TBI patients into two categories of risk for spontaneous progression. This supports tailored chemoprophylaxis regimens for each arm.

Does isolated traumatic subarachnoid hemorrhage merit a lower intensity level of observation than other traumatic brain injury?

Evidence is emerging that isolated traumatic subarachnoid hemorrhage (ITSAH) may be a milder form of traumatic brain injury (TBI). If true, ITSAH may not benefit from intensive care unit (ICU) admission, which would, in turn, decrease resource utilization. We conducted a retrospective review of all TBI admissions to our institution between February 2010 and November 2012 to compare the presentation and clinical course of subjects with ITSAH to all other TBI. We then performed descriptive statistics on the subset of ITSAH subjects presenting with a Glasgow Coma Score (GCS) of 13-15. Of 698 subjects, 102 had ITSAH and 596 had any other intracranial hemorrhage pattern. Compared to all other TBI, ITSAH had significantly lower injury severity scores (p<0.0001), lower head abbreviated injury scores (p<0.0001), higher emergency department GCS (p<0.0001), shorter ICU stays (p=0.007), higher discharge GCS (p=0.005), lower mortality (p=0.003), and significantly fewer head computed tomography scans (p<0.0001). Of those ITSAH subjects presenting with a GCS of 13-15 (n=77), none underwent placement of an intracranial monitor or craniotomy. One subject (1.3%) demonstrated a change in exam (worsened headache and dizziness) concomitant with a progression of his intracranial injury. His symptoms resolved with readmission to the ICU and continued observation. Our results suggest that ITSAH are less-severe brain injuries than other TBI. ITSAH patients with GCS scores of 13-15 demonstrate low rates of clinical progression, and when progression occurs, it resolves without further intervention. This subset of TBI patients does not appear to benefit from ICU admission.

Suboccipital decompression during posterior cranial vault remodeling for selected cases of Chiari malformations associated with craniosynostosis.

OBJECT: The optimal management of Chiari malformations in the setting of craniosynostosis is not well established. In this report the authors describe their outcomes with the combined technique of simultaneous suboccipital decompression (SOD) during posterior cranial vault remodeling (PCVR). METHODS: A retrospective review was performed of all patients undergoing PCVR and simultaneous SOD. Demographic data, diagnosis, imaging studies, operative intervention, and clinical follow-up were evaluated. RESULTS: Thirty-four patients were identified as having undergone a simultaneous PCVR/SOD for Chiari malformation associated with craniosynostosis. Eighty-eight percent of these patients had syndromic, multisutural craniosynostosis, and the remaining patients had unilateral lambdoid craniosynostosis. There were no postoperative complications as a direct result from this combined procedure. Two patients required a subsequent direct approach for decompression of the Chiari malformation. The interval between these subsequent surgeries was 3 years and 19 months. CONCLUSIONS: Chiari malformations are commonly associated with syndromic, complex craniosynostosis and isolated lambdoid craniosynostosis. In appropriately selected patients, a combined posterior cranial vault enlargement and SOD of the foramen magnum is associated with a low complication rate and appears to be an effective procedure.

The A1-A2 diameter ratio may influence formation and rupture potential of anterior communicating artery aneurysms.

BACKGROUND: Specific morphological factors contribute to the hemodynamics of the anterior communicating artery (AComA). No study has examined the role of the A2 segment on AComA aneurysm presence and rupture. OBJECTIVE: To examine the possibility that the ratio between A1 and A2 segments (A1-2 ratio) represents an independent risk factor for presence and rupture of AComA aneurysms (AComAAs). METHODS: A retrospective review of an institutional aneurysm database was performed; patients with ruptured and unruptured AComAAs were identified. Two control groups were selected: group A (posterior circulation aneurysms) and group B (patients without intracranial aneurysms or other vascular malformations). Measurements of A1 and A2 diameters were obtained from digital subtraction angiography (64.1% of 3-D rotational digital subtraction angiography), and the A1-2 ratio calculated. RESULTS: From January 2009 to April 2011, 156 patients were identified (52 AComAAs, 54 control group A, and 50 control group B). Mean age at the time of presentation was 56.09 years. Compared with both control groups, patients with AComAAs had greater A1 diameter (P < .01) and A1-2 ratio (P < .001) and smaller A2 diameter (P < .01). The A1-2 ratio correlated positively with the presence of AComAAs (P < .001). Ruptured AComAAs were smaller than unruptured ones (5.91 mm vs 9.25 mm, P = .02) and associated with a higher A1-2 Ratio (P = .02). The presence of a dominant A1 did not predict AComAA rupture (P = .15). The A1-2 ratio correlated positively with the presence of ruptured AComAAs (P = .04). CONCLUSION: A1-2 ratio correlates positively with the presence and rupture of AComAAs and may facilitate treatment decision in cases of small, unruptured AComAAs.