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BackgroundDuring the Coronavirus disease (COVID-19) pandemic, countries implemented border control and quarantine measures to reduce transmission. The Alberta Border Testing Pilot Program (ABTPP) allowed international travellers entering Alberta to reduce their quarantine period following two negative COVID-19 tests. We evaluated participant experiences with the ABTPP and implementation.MethodWe used a parallel convergent mixed-methods design to explore participant experiences through electronic web-based questionnaires (n = 21,089; n = 13,839) and semi-structured telephone interviews (n = 30). We evaluated implementation through three staff focus groups (n = 11). We analysed questionnaires using descriptive statistics and analysed interviews using inductive and deductive thematic analysis. We deductively coded focus group data using the 2009 Consolidated Framework for Implementation Research (CFIR).ResultsQuestionnaires indicated minimal issues with registration forms (91.7%), symptom reports (95.5%), and COVID-19 testing (95.7%). Most respondents (95.1%) expressed willingness to participate in the ABTPP again. Interviews revealed three themes related to participant experience: program efficiency, clarity of information, and requisite effort. Focus groups identified key implementation facilitators including the single health information system, strong stakeholder partnerships, and good communication across partnerships. Barriers included program complexity, implementation timeline, and evolving external context.DiscussionParticipants reported high satisfaction with the ABTPP. Border testing programs should have high efficiency, require low effort, and use messaging that is clear and consistent. The effective implementation of border testing programs may be facilitated by strong leadership, adaptability, automated components, good communication, and simple technology. Learnings from participants and staff may help improve the implementation of border control programs for future pandemics or other emergencies.ConclusionsThe ABTTP was a novel border control measure during the COVID-19 pandemic. Our evaluation of both participant and staff experiences demonstrated high levels of traveller satisfaction and identified areas for improvement that can inform the development of future border control measures.

A distinction is often made between two traditions of British Conservative thought: the paternalist “one nation/middle way” tradition, and the more libertarian one that is associated with Margaret Thatcher. Typically, this distinction is mapped onto the ideas that Conservatives hold about equality. While “one nation” Conservatives condone some forms of redistribution, their libertarian counterparts, it is argued, do not. This article reassesses this distinction by comparing the political thinking of two representatives of the two traditions: Harold Macmillan and Margaret Thatcher. Comparing Macmillan and Thatcher’s views on equality, it is argued, is inappropriate as a way of distinguishing between their respective ideologies. Instead, we should draw a distinction between the way that Macmillan and Thatcher arrived at their views about equality. On his part, Macmillan adopted a triadic logic. By conceiving of a “middle way”, he defined his conservatism in relation to the dangerous “extremes” of free market capitalism and state socialism. Thatcher, by contrast, adopted a dyadic logic. Instead of locating herself between two “extremes”, she employed a series of binary distinctions to establish her conception of conservatism. Freedom was preferred to equality; the market was preferred to the state, and so on. The article explores the implications of these differing logics, and it concludes if we are to identify different variants of conservatism, we should be just as concerned with their modes of negation as we are with the affirmative claims they make about concepts like equality.

Abstract Background Advanced physiotherapist-led services have been embedded in specialist orthopaedic and neurosurgical outpatient departments across Queensland, Australia, to ameliorate capacity constraints. Simulation modelling has been used to inform the optimal scale and professional mix of services required to match patient demand. The context and the value of simulation modelling in service planning remain unclear. We aimed to examine the adoption, context and costs of using simulation modelling recommendations to inform service planning. Methods Using an implementation science approach, we undertook a prospective, qualitative evaluation to assess the use of discrete event simulation modelling recommendations for service re-design and to explore stakeholder perspectives about the role of simulation modelling in service planning. Five orthopaedic and neurosurgical services in Queensland, Australia, were selected to maximise variation in implementation effectiveness. We used the consolidated framework for implementation research (CFIR) to guide the facilitation and analysis of the stakeholder focus group discussions. We conducted a prospective costing analysis in each service to estimate the costs associated with using simulation modelling to inform service planning. Results Four of the five services demonstrated adoption by inclusion of modelling recommendations into proposals for service re-design. Four CFIR constructs distinguished and two CFIR constructs did not distinguish between high versus mixed implementation effectiveness. We identified additional constructs that did not map onto CFIR. The mean cost of implementation was AU$34,553 per site (standard deviation = AU$737). Conclusions To our knowledge, this is the first time the context of implementing simulation modelling recommendations in a health care setting, using a validated framework, has been examined. Our findings may provide valuable insights to increase the uptake of healthcare modelling recommendations in service planning.

The axis deer (Axis axis) was imported from Germany and introduced into Brijuni in 1911. Brijuni are a group of islands in the Adriatic Sea along the western coast of the southern peak of the Istrian Peninsula in the Republic of Croatia. In 1983 the area was declared a National Park. The objective of this paper was to research the adaptation of the axis deer to living conditions on the islands. Observation has shown that on the Brijuni islands the axis deer lives in herds comprising 10 to 30 individuals. The youngest male deer seeking access to does was four years old, while at the age of fi ve they started roaring. Deer fi ghts are not frequent during roaring period. The natural grazing rhythm is disturbed by the vast number of tourists. The calving periods of the axis deer during the year indicate three well-pronounced ruts, namely January to February, July-August and October-November. They also show that oestrus occurs soon after calving in most of the females. Gestation period of does is 7 to 7.8 months. 85% of the does on the Brijuni Islands produce their offspring in the warmer part of the year, between 1 March and 31 September. The population of the axis deer in the area of the Brijuni National Park is stable, rather numerous (about 100 individuals) and well acclimatized, and as such it presents reproductive material suitable to populate enclosed hunting grounds and big game farms.

Dean Blevins1,2,3, Bridget Morton4, Rene McGovern5,61South Central Mental Illness Research, Education, and Clinical Center (SC-MIRECC), Central Arkansas Veterans Healthcare System; 2University of Arkansas for Medical Sciences; 3University of Phoenix, Little Rock Campus, Little Rock, AR; 4Northeast Missouri Health Network, Kirksville, MO; 5A.T. Still University/Kirksville College of Osteopathic Medicine, Kirksville, MO; 6Case Western Reserve University, Cleveland, OHAbstract: The purpose of this evaluation was to explore the collaborative nature of partners in a rural mental health program for the elderly, and to test an adapted method of assessing the collaborative process. Sixteen collaborative partners were interviewed to explore ratings of collaboration across 6 domains identified as critical to participatory research. Results indicate that the context of rural Missouri and uniqueness of the program necessitated an approach to collaboration that began with a top-down approach, but greater community responsibility developed over time. Partners recognized the efforts of the program’s directors to seek input. Most were satisfied with their roles and the degree of success achieved by the program, although several wanted to have more input in the future in some domains, but not in others. Interviews revealed numerous barriers to achieving sustainability. Methods to improve the assessment of collaboration are discussed and areas for improvement are offered.Keywords: community-based participatory research, elderly, mental health, older adults, rural

The aim of this study was to determine the outcome of dogs with soft tissue sarcoma (STS) within the region of the ischiatic tuberosity (ITSTS) treated surgically. This was a multi-institutional retrospective study. Fifty-two dogs met the inclusion criteria, which were: histologically confirmed STS in the region of the IT treated with surgical resection between March 1st, 2009 and March 1st, 2021 with a minimum follow-up time of 6 months. Data collected included patient signalment, preoperative diagnostics, surgical intent/method, surgical complications, histopathology, margins, outcome and cause of death. Statistical analyses were performed to determine significant factors in the treatment and prognosis of ITSTS. Overall survival time (OST) and disease progression were negatively associated with tumour grade, while recurrence was positively associated with grade and incomplete margins. Of the 52 included dogs, there were 24 grade I, 20 grade II and 7 grade III tumours. Forty dogs had reported histopathologic margins of which 26 were reported to be complete and 14 were incomplete. OST and progression-free survival was not reached for tumours graded as I or II and was 255 and 268 days respectively, for grade III. Median time to recurrence was not reached for tumours excised with complete margins and was 398 days for those with incomplete margins. The surgical complication rate was 25%. ITSTS was not found to be a unique clinical entity in dogs as tumour behavior, treatment recommendations, and prognosis were similar to STS in other locations, with overall outcome and prognosis influenced by histologic grade and margins. While surgical complications were common, none resulted in significant morbidity or mortality., (© 2022 John Wiley & Sons Ltd.)

Objectives: To investigate the effect of breed as a risk factor associated with humeral condylar fracture in skeletally immature dogs in the UK., Materials and Methods: Retrospective study of dogs under 12 months of age that were presented with humeral condylar fracture to three specialist referral centres between 2015 and 2018. Data retrieved from medical records included breed, age, gender, neuter status, affected limb, fracture configuration and aetiology of the fracture. Breed population percentages were compared with those recorded by the UK Kennel Club., Results: Of the 115 dogs with 118 fractures, French bulldogs (41%) and English springer spaniels (15%) were overrepresented: humeral condylar fractures were more commonly diagnosed in French bulldogs (odds ratio = 5.86) and English springer spaniels (odds ratio = 5.66) compared with mixed-breed dogs. Lateral condylar fractures occurred in 70% of cases, with medial condylar fractures and Y/T fractures accounting for 9% and 21%, respectively. Median age at the time of fracture was 4 months (range 2 to 10 months)., Clinical Significance: French bulldogs and English springer spaniels were identified as being at potentially increased risk of humeral condylar fracture in skeletally immature dogs., (© 2020 British Small Animal Veterinary Association.)

A 21 wk old, 2 kg neutered male domestic shorthair presented with a 24 hr history of acute-onset severe nonambulatory tetraparesis with no known inciting cause. Neurologic examination revealed a C1-C5 myelopathy. Computed tomography of the vertebral column and thorax revealed incomplete ossification of the C2 and C3 vertebrae and lung bullae. After 4 wk of conservative management, the client reported a return to normal ambulation with reluctance to jump up. To the authors' knowledge, this is the first report of a feline case of incomplete ossification of cervical vertebrae. The cervical malformations outlined in this report are differentials to consider in cases of acute-onset tetraparesis in cats.

Study Design: Correlation of locations of sacral insufficiency fractures is made to regions of stress depicted by finite element analysis derived from biomechanical models of patient activities., Objective: Sacral insufficiency fractures occur at consistent locations. It was postulated that sacral anatomy and sites of stress within the sacrum with routine activities in the setting of osteoporosis are foundations for determining patterns for the majority of sacral insufficiency fractures., Summary of Background Data: The predominant vertical components of sacral insufficiency fractures most frequently occur bilaterally through the alar regions of the sacrum, which are the thickest and most robust appearing portions of the sacrum instead of subjacent to the central sacrum, which bears the downward force of the spine., Methods: First, the exact locations of 108 cases of sacral insufficiency fractures were catalogued and compared to sacral anatomy. Second, different routine activities were simulated by pelvic models from CT scans of the pelvis and finite element analysis. Analyses were done to correlate sites of stress with activities within the sacrum and pelvis compared to patterns of sacral insufficiency fractures from 108 cases., Results: The sites of stress depicted by the finite element analysis walking model strongly correlated with identical locations for most sacral and pelvic insufficiency fractures. Consistent patterns of sacral insufficiency fractures emerged from the 108 cases and a biomechanical classification system is introduced. Additionally, alteration of walking mechanics and asymmetric sacral stress may alter the pattern of sacral insufficiency fractures noted with hip pathology (P = 0.002)., Conclusion: Locations of sacral insufficiency fractures are nearly congruous with stress depicted by walking biomechanical models. Knowledge of stress locations with activities, cortical bone transmission of stress, usual fracture patterns, intensity of sacral stress with different activities, and modifiers of walking mechanics may aid medical management, interventional, or surgical efforts.

We report the imaging features of 4 cases of patients with papillary tumor of the pineal region, a tumor newly recognized in the 2007 World Health Organization "Classification of Tumors of the Nervous System." In each case, the tumor was intrinsically hyperintense on T1-weighted images with a characteristic location in the posterior commissure or pineal region. The pathologic hallmarks of the tumor are discussed, including a possible explanation for the MR imaging characteristics in our cases.

Background and Purpose: Dissection and retraction of the sylvian fissure can cause venous insufficiency and may be an important contributor to postoperative edema or hemorrhage after clipping of a middle cerebral artery (MCA) aneurysm. The incidence of changes in the superficial middle cerebral vein (SMCV) and adjacent veins and whether such changes increase the amount of edema or hemorrhage on postoperative CT is the focus of this study., Methods: Pre- and postoperative angiograms of 100 consecutive patients with MCA aneurysms treated by craniotomy and clipping were compared to determine the postoperative incidence of changes involving the SMCV. CTs from the normal and abnormal postoperative venous groups were compared to determine the amount of edema or presence of parenchymal hemorrhage., Results: Postoperatively, 31 (31%) SMCVs were altered, 20 to a minor or moderate degree. Eleven cases were pronounced. In 9 (9%) cases, the SMCV was completely obscured or failed to fill on postoperative angiography. More edema (observer 1, P < .0002; observer 2, P < .0006) and small brain parenchymal hemorrhages (observer 1, P < .00003; observer 2, P < .00001) were found on the postoperative CT images of the group whose SMCVs were altered than those that were unchanged., Conclusions: Neurosurgeons and neuroradiologists should be attentive to changes in the SMCV and adjacent venous structures to optimize outcomes of procedures involving the sylvian fissure.

An 18-year-old female patient with unilateral hearing loss underwent evaluation with CT and MR imaging. A partially ossified, enhancing lesion in the bony labyrinth, with replacement of adjacent structures, was identified. Surgical biopsy revealed a meningioma arising primarily within the bony labyrinth. To our knowledge, this entity has not been previously described.

Imaging the skull base after surgery can be challenging because anatomic structures may have been destroyed by an underlying process or removed at surgery. Foreign substances may be introduced to fill a void left by tumor resection, for hemostasis, and to repair dural defects. Previous imaging studies must be available for comparison to understand the characteristics of an underlying lesion. By following the progression of a lesion on subsequent imaging studies, the nature of treatment-related changes and residual or recurrent pathology is best realized.

Conventional angiography has lost its preeminence as a screening tool for extracranial carotid artery disease. Similarly, conventional angiography may be at the crossroads for its use as a presurgical planning study for carotid endarterectomy. This article discusses angiographic techniques and atherosclerotic carotid artery disease involving the carotid bifurcation. Special emphasis is placed in discussing the role of angiography in the recent large prospective trials evaluating endarterectomy for carotid artery disease.

Rationale and Objectives: The authors determine the reliability of centralized versus noncentralized (site-based) measurement of angiographic stenosis of patients enrolled into the multicenter, prospective, Asymptomatic Carotid Atherosclerosis Study by angiographic studies., Methods: Percent agreements and correlations of 244 masked and prospectively interpreted angiograms were calculated for comparison of centralized and noncentralized readers measuring the percent carotid stenosis from the same angiographic studies. Univariate summary statistics for differences in percent stenoses were calculated for these readings., Results: Agreement between readings were 88.5% and 91.8% with kappa statistics of 0.77 and 0.73 for > or = 60% and > or = 80% stenosis, respectively, for comparison of 33 centers to the designated central reader. Comparison between the designated central reader and a second central reader derived percent agreements of 85.0% and 86.5% with kappa statistics of 0.69 and 0.41 for > or = 60% and > or = 80% stenoses, respectively, for arteries selected from the original group. Hence, agreement was slightly better between the enrolling centers and the designated central reader than between the two central readers., Conclusions: Both centralized and noncentralized (site-based) methods of angiographic measurement of stenosis are equally reliable for large, prospective, masked, multicenter trials when quality control measures are instituted to ensure uniform application of eligibility criteria.

Facial and skull base trauma can cause clinically significant epistaxis. Optimal evaluation and treatment require knowledge of the pertinent vascular and skull base anatomy. We describe a patient with extensive skull base injury and epistaxis in whom CT revealed a fracture through the roof of the nasopharynx and arteriography showed injury to the pterygovaginal (pharyngeal) artery. The fracture was successfully treated with transarterial particulate embolization.

Purpose: To evaluate the results of balloon angioplasty of 17 stenoses resulting from intracranial atherosclerosis and vasculitis., Methods: Seventeen skull-base and intracranial lesions were dilated with a microballoon angioplasty catheter., Results: Initially, 16 of the 17 stenoses showed improvement at angiography. Moderate residual stenosis was found in 2 of 12 atherosclerotic lesions, both in the distal vertebral artery. Angioplasty in 1 of 12 atherosclerotic lesions caused worsening of the stenotic site, also in the distal V4 region of the vertebral artery. All but one of the patients improved clinically. However, all five lesions caused by acute vasculitis progressed to occlusion after initial improvement., Conclusion: Intracranial percutaneous transluminal angioplasty is a viable nonsurgical option for the treatment of atherosclerotic vascular insufficiency, but it may not be as successful in treating lesions caused by vasculitis in the acute phase.

We report a case of a carotid-cavernous fistula through a persistent trigeminal artery with endovascular treatment, and discuss the Saltzman classification of persistent trigeminal artery anatomy and its importance in treatment of this lesion.

Objective: This article focuses on an unusual cross-sectional imaging pattern of a deep developmental venous anomaly (DVA). Since these anomalies are nonpathologic, they must not be interpreted as a disease that requires further costly workup and potentially injurious procedures (cerebral angiography)., Materials and Methods: Two women aged 19 (Case 1) and 30 (Case 2) years sought medical evaluation for severe headaches. Both patients underwent CT, MRI, and conventional cerebral angiography. Case 1 also underwent MR venography., Results: The diagnosis of an unusual DVA in Case 1 was confirmed only after conventional catheter angiography and a follow-up MR venogram. In Case 2 the diagnosis was inferred based upon the CT, MRI, and conventional angiography results and the marked similarity to Case 1. The presumptive diagnosis in Case 2 would not have been made with confidence without the prior experience of managing Case 1., Conclusion: DVAs (venous angiomas) are extreme variations in the pattern of intracranial venous drainage. These two case reports highlight an unusual pattern of this benign entity. Individuals interpreting cross-sectional imaging studies should be cognizant of this pattern.

The purpose of this article is to report on the safety and effectiveness of brain arteriovenous malformation (AVM) embolization for two series of patients, of which one was treated with particulate embolization and the other with acrylic embolization. Sixty-five consecutive patients from embolization logs and patient records from 1988 to 1993 were reviewed. AVMs were routinely treated with particulate embolization early in the review (1988-1991), and after a transition period, the technique was changed to acrylic embolization for the remainder of the study period (1992-1993). All patients were treated with the ultimate goal of complete AVM obliteration. AVMs were embolized and resected, if possible, and if unresectable, they were reduced in size with embolization and radiated. The course of treatment for each patient was reviewed. The effectiveness at the end of treatment was analyzed for the ability to resect the AVM and, if unresectable, the ability to reduce the AVM to radiation size. Additionally, the safety of each embolization technique was evaluated in the context of comprehensive care, in terms of the safety of the procedure itself, the surgical resection after embolization, and the outcome at the end of comprehensive treatment. This article outlines the safety and effectiveness of acrylic and particulate embolization at a single institution. The ability to surgically resect an AVM after embolization and to reduce nidus size with acrylic was at least comparable with that with particulate embolization. Comprehensive complication rates were lower after acrylic embolization and were heavily influenced by a decreased number of surgical complications in the acrylic series. These data support the need to conduct a randomized prospective clinical trial to compare the relative safety and effectiveness of the two methods of embolization.

Intraarterial thrombolysis for acute cerebrovascular occlusion has achieved recanalization at a 50-90% rate. Clinical outcome has been unpredictable. The authors sought to test the hypothesis that intrathrombus administration of recombinant tissue plasminogen activator (rt-PA) would improve recanalization rate and to assess the possibility that clinical outcome would be predicted by the extent of collateral flow. Seven patients with acute cerebrovascular occlusion (less than six hours in 6, twenty-four hours in 1) were treated with intrathrombus rt-PA at 1 mg/minute. Examinations were scored on a five-point motor scale. Collateral flow was assessed angiographically. Vessels recanalized in 5 patients, 3 of whom had good outcomes. Vessels failed to recanalize in 2 patients, 1 of whom had good outcome. Good collateral flow was evident in all 4 patients with good outcome and in none of those with poor outcome. Intrathrombus administration of rt-PA is technically feasible. Favorable clinical outcome is more likely in the presence of good collateral flow. In the absence of good collateral flow, ultra-early intervention may be necessary.

Purpose: To evaluate the clinical efficacy, cost-effectiveness, and safety of presurgical devascularization of meningiomas., Methods: Matched samples of embolized and nonembolized groups of meningiomas were compared. The study variables for clinical efficacy were estimated blood loss, number of transfusions, surgical resection time, and length of hospitalization. The cost-effectiveness was evaluated by adjusting all hospital costs to 1991 dollar amounts, and adding additional embolization costs and fees to the hospital cost totals for the embolized group. A qualitative comparison of complications was made., Results: All dependent variables evaluating the clinical efficacy of the procedure (estimate blood loss, 533 cc versus 836 cc; number of transfusions, 0.39 units versus 1.56 units; surgical resection time, 305.8 minutes versus 337.5 minutes; and length of hospitalization, 10.6 days versus 15.0 days) displayed trends of higher means in the nonembolized group; however, only the estimated blood loss and number of transfusions variables were significant. The cost-effectiveness of the procedure was not statistically significant. The mean cost was $29,605 for the embolized group and $38,449 for the nonembolized group. There were three major and nine minor complications in the nonembolized group and zero major and six minor complications in the embolized group. There were four additional minor complications caused by the embolization procedure., Conclusion: Endovascular devascularization of meningiomas is beneficial for large meningiomas because it diminishes the necessity of intraoperative transfusions and decreases blood loss. The additional day of hospitalization, emolization costs, and costs of complications do not conversely increase treatment costs. There were no major complications or adverse long-term effects caused by the embolization procedure.

Purpose: To examine the incidence of neurologic complications associated with modern cerebral angiography and to assess patient characteristics associated with an increased risk of complications., Methods: One thousand consecutive cerebral angiographic procedures were evaluated prospectively. Examinations were performed using transfemoral catheterization and film-screen methods. For purposes of this trial, a neurologic complication was defined as any new focal neurologic deficit or change in mental status occurring during the angiogram or within the following 24 hours. Patients were evaluated during and at the completion of angiography. Follow-up evaluations were performed on the day of and the day after angiography., Results: There were a total of 10 neurologic complications within 24 hours of angiography, 5 of which were persistent. Onset of 5 of the deficits occurred during angiography, the other 5 (3 persistent) were delayed. All complications occurred in patients being evaluated for stroke/transient ischemic attack or (in one case) asymptomatic bruit. A higher average age, longer average procedure time, and greater volume of radiographic contrast was noted in these patients than in the study population., Conclusion: Cerebral angiography was associated with a 1% overall incidence of neurologic deficit and a 0.5% incidence of persistent deficit. All complications occurred in patients presenting with a history of stroke/transient ischemic accident or carotid bruit, which may reflect the difficulty of performing angiography in this population at risk for atherosclerotic changes.

The refinement in the intravascular techniques has revolved upon the development of new material and a better understanding of neurophysiology. Access has become less of a limitation, and more emphasis is now placed on getting the job done: closing a fistula, obliterating a malformation, or filling an aneurysm. Embolic materials available have greatly changed according to the indication at hand. The focus now is on the specific uses for the agent instead of toxicity or dose-response trials.

Purpose: To compare the clinical efficacy of a dual-echo fast spin-echo imaging technique, SHARE (share-view acquisition using repeated echoes), with conventional long-repetition-time spin-echo imaging., Methods: Conventional spin-echo and SHARE fast spin-echo MR images of the brain were acquired in 50 randomized patients and interpreted separately in conjunction with the T1-weighted images. All images were reviewed independently by two neuroradiologists who were blinded to the clinical history and previous interpretations., Results: The diagnoses rendered for the spin-echo and SHARE images were concordant in 48 of the 50 subjects (96%) by the first reader and in all 50 cases (100%) by the second reader. SHARE images were acquired in one-fourth of the imaging time yet image contrast, quality, and sensitivity to long T2 lesions were comparable. The SHARE technique was less sensitive to hemorrhagic residua., Conclusions: SHARE is a viable time-saving alternative to the conventional long-repetition-time pulse sequence. Although SHARE images are not as sensitive to magnetic susceptibility effects, the time saved using this technique could be used to perform a gradient-echo sequence when indicated.

Twelve patients with a high suspicion of brain metastases by previous clinical or radiologic examinations were studied in a phase III investigation with magnetic resonance (MR) imaging at 1.5 T after a bolus intravenous injection of 0.1 mmol/kg gadoteridol followed at 30 minutes by a second bolus injection of 0.2 mmol/kg gadoteridol. All lesions were best demonstrated (showed greatest enhancement) at the 0.3-mmol/kg (cumulative) dose, with image analysis confirming signal intensity enhancement in the majority of cases after the second gadoteridol injection. More lesions were detected with the 0.3-mmol/kg dose than with the 0.1-mmol/kg dose, and more lesions were detected with the 0.1-mmol/kg dose than on precontrast images. In this limited clinical trial, high-dose gadoteridol injection (0.3-mmol/kg cumulative dose) provided improved lesion detection on MR images specifically in intracranial metastatic disease.

Purpose: To assess the degree and regional pattern of first-pass brain enhancement using dynamic MR imaging., Materials and Methods: Ultrafast MR imaging (1.06-second acquisition time per image) was performed in 19 healthy subjects following a bolus IV injection of a gadolinium contrast agent; 36 patients with suspected pathology were studied using the same protocol., Results: Calculated percent blood volumes were 4.9% for right cortical gray matter, 4.8% for left cortical gray matter, and 2.6% for white matter. Subtraction images were obtained that depicted the first pass "blood pool" pattern of enhancement (gray and white matter) which was significant., Conclusion: Preliminary evidence suggests utility for cerebral "blood pool" imaging, especially if reduced image acquisition times can be achieved.

We describe a rapid MR imaging technique, applying functional analysis to images obtained during the tissue transit of injected contrast material into the cerebral circulation, which has potential for assessment of the altered hemodynamics in cerebral ischemia. This technique utilized turbo-FLASH imaging maximizing the T1 relaxivity properties of gadopentetate dimeglumine with positive contrast enhancement.

In this phase III study, 411 adult patients with suspected intracranial or spinal disease underwent magnetic resonance (MR) imaging before and after intravenous injection of 0.1 mmol/kg gadoteridol (gadolinium 1,4,7-tris [carboxymethyl]-10-[2'-hydroxypropyl]-1,4,7,10-tetraazacyclododecane+ ++). MR images were evaluated by a single unblinded reader at each of 27 sites; the diagnosis was confirmed with one of nine imaging or surgical procedures within 8 weeks before or after MR imaging. After injection, no clinically significant changes were noted in laboratory values, physical examination, or vital signs. Adverse clinical events possibly or probably associated with injection of gadoteridol were seen in 18 of 411 patients (4.4%); the most common were dysgeusia and mild nausea, and all abated without residual effects. MR images enhanced with gadoteridol in patients with confirmed disease provided more diagnostic information than unenhanced images in 128 of 175 brain examinations (73.1%) and 93 of 137 spinal examinations (67.9%). A change in diagnosis because of additional information from contrast-enhanced images was considered likely in 63 of 214 cranial and 54 of 161 spinal studies.

The authors present the case of a child with a predominantly unilateral craniofacial fibrous dysplasia and a substantial redirection of internal carotid blood flow to the dysplastic bone. The case illustrates the advantages of using multiple imaging modalities in the evaluation of this disorder. CT showed the diagnostic findings of fibrous dysplasia and demonstrated the extent of bony involvement. MRI showed the extent and vascularity of the intradiploic fibrous mass and best demonstrated the distortion of underlying cerebral structures. Tc-99m HM-PAO brain scintigraphy demonstrated adequate ipsilateral cerebral perfusion, thereby excluding any significant cerebral "steal."

MRI of the spine and its contents is fast becoming the study of choice over CT myelography for the evaluation of spinal pathology. MRI is able to generate sagittal and coronal images in addition to axial images, to image the entire spine, and to produce a myelogramlike picture. These capabilities give MRI a distinct advantage over CT myelography not only because no intrathecal contrast injection is needed but also because intramedullary lesions, edema, and syrinx may be differentiated from each other by conventional, noncontrast, spin-echo MRI. This article reviews the current philosophies regarding contrast-enhanced MRI with gadopentate dimeglumine in the evaluation of the spine and its contents. It will provide an imaging strategy and approach to evaluation, briefly discuss spin-echo and gradient-echo pulse sequences, and give contrast indications focusing on disorders that benefit from the use of injected, intravenous gadopentate dimeglumine. Potential imaging artifacts related to spin-echo and gradient-echo imaging pertinent to imaging of the spine will also be discussed.

The findings at magnetic resonance (MR) imaging in a group of 36 pathologically verified supratentorial gliomas were analyzed and compared with the biopsy diagnoses (a) to determine whether MR imaging could be used to classify astrocytic-series tumors into a three-tiered system of low-grade astrocytoma, anaplastic astrocytoma, and glioblastoma multiforme; and (b) to evaluate MR imaging features that may aid in this classification. The MR characteristics evaluated were crossing of the midline, edema, tumor signal heterogeneity, hemorrhage, border definition, cyst formation or necrosis, and mass effect. The statistically significant MR characteristics (positive predictors) were mass effect (P = .0000) and cyst formation or necrosis (P = .0512). The MR accuracy rate approached that of neuropathologic diagnosis, which is subject to sampling errors. MR imaging may serve as an adjunct in case management when the clinical course and MR findings appear to be at odds with the neuropathologic diagnosis.

The chest radiographs of 10 babies who developed an abrupt diffuse pulmonary parenchymal opacification in conjunction with pulmonary hemorrhage, pulmonary edema, or pneumonia as a complication of hyaline membrane disease were reviewed. The chest radiographs of these 10 babies were compared to five radiographs obtained with various degrees of expiration in four babies with uncomplicated hyaline membrane disease. The comparison indicates that analysis of air bronchograms facilitates discrimination of pulmonary opacification due to filming in expiration from pathologic diffuse parenchymal opacification in babies with hyaline membrane disease. Expiration produces constriction and centralization of air bronchograms. Alveolar filling processes are associated with distension and peripheral extension of air bronchograms.