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BACKGROUND AND PURPOSE: Endovascular options for therapy for patients with vasospasm after SAH include angioplasty and intra-arterial vasodilator infusion. Preliminary studies of the effects of the calcium channel antagonist verapamil on angiographic vasospasm have yielded mixed and/or qualitative results. In this study, improvement in angiographic vasospasm after intra-arterial verapamil administration is demonstrated with quantitative, blinded methods. MATERIALS AND METHODS: This retrospective observational case series includes 12 patients with vasospasm after SAH who collectively received 16 treatments with intra-arterial verapamil during a 2-year period at our institution. The exclusion criterion was concurrent treatment with angioplasty. Blinded reviewers quantitatively evaluated angiograms from each patient and/or treatment after presentation with SAH and before and after intra-arterial treatment of vasospasm. RESULTS: Patients were treated with intra-arterial verapamil for vasospasm 9 ± 4 days after SAH with a range from 1 to 16 days. For the 34 arterial distributions treated, the segment with the worst angiographic vasospasm from each arterial distribution averaged 51 ± 13% stenosis, which improved to 29 ± 18% stenosis (P < .001). There was no significant difference in treatment effect in proximal arterial segments, which may be amenable to angioplasty, compared with distal segments (P > .05). There was no significant difference in treatment effect in arterial segments previously subjected to angioplasty compared with other segments (P > .05). CONCLUSIONS: Intra-arterially administered verapamil improves angiographic vasospasm after SAH when administered at 10 ± 3 mg per arterial distribution. Optimal dose, infusion rate, and retreatment interval remain to be determined. Randomized controlled trials are needed to prove efficacy in the treatment of clinical vasospasm.

BACKGROUND AND PURPOSE: Thromboembolic events are the most common complications of elective coil embolization of cerebral aneurysms. Administration of oral clopidogrel and/or aspirin could lower the thromboembolic complication rate. MATERIALS AND METHODS: Records over a 10-year period were reviewed in a retrospective cohort study. For 369 consecutive elective coil embolization procedures, 25 patients received no antiplatelet drugs, 86 received antiplatelet drugs only after embolization, and 258 received antiplatelet drugs before and after embolization. RESULTS: Symptomatic thromboembolic complications (transient ischemic attack or stroke within 60 days) occurred in 4 (16%) of 25 when no antiplatelet drugs were given, in 2 (2.3%) of 86 when antiplatelet drugs were administered only after embolization, and in 5 (1.9%) of 258 when antiplatelet drugs were administered before and after embolization. The lower symptomatic thromboembolic complication rate in the patients who received any antiplatelet therapy was statistically significant ( P = .004). Clots were visible intraprocedurally in 5 (4.5%) of 111 when no antiplatelet drugs were administered before procedures and in 4 (1.6%) of 258 when they were ( P value not significant). None of the 9 was symptomatic postprocedurally, but 7 were lysed or mechanically disrupted. Extracerebral hemorrhagic complications occurred in 0 (0%) of 25 when no antiplatelet drugs were given and in 11 (3.2%) of 344 when they were ( P value not significant). CONCLUSION: Oral clopidogrel and/or aspirin significantly lowered the symptomatic thromboembolic complication rate of elective coil embolization of unruptured cerebral aneurysms. There were trends toward a lower rate of intraprocedural clot formation in patients given antiplatelet drugs before procedures and a higher hemorrhagic complication rate in patients given antiplatelet drugs. Benefits of antiplatelet therapy appear to outweigh risks.

Background and purposePerimesencephalic subarachnoid hemorrhage (PSAH) is not consistently defined in the existing literature. The purpose of this study was to test the inter-observer variability and specificity for non-aneurysmal subarachnoid hemorrhage (SAH) of an anatomic definition of PSAH.MethodsMedical records of all patients who underwent catheter angiography for evaluation of non-traumatic SAH between July 2002 and April 2012 were reviewed. Patients with anterior circulation aneurysms were excluded. Three blinded reviewers assessed whether each admission CT scan met the following anatomic criteria for PSAH: (1) center of bleeding located immediately anterior and in contact with the brainstem in the prepontine, interpeduncular, or posterior suprasellar cistern; (2) blood limited to the prepontine, interpeduncular, suprasellar, crural, ambient, and/or quadrigeminal cisterns and/or cisterna magna; (3) no extension of blood into the Sylvian or interhemispheric fissures; (4) intraventricular blood limited to incomplete filling of the fourth ventricle and occipital horns of the lateral ventricles (ie, consistent with reflux); (5) no intraparenchymal blood.Results56 patients with non-aneurysmal SAH and 50 patients with posterior circulation or posterior communicating artery aneurysms were identified. Seventeen (16%) of the 106 admission CT scans met the anatomic criteria for PSAH. No aneurysm was identified in this subgroup. Inter-observer agreement was excellent with κ scores of 0.89–0.96 and disagreement in 2.8% (3/106) of cases.ConclusionsOur anatomic definition of PSAH correlated with a low risk of brain aneurysm and was applied with excellent inter-observer agreement.

There is limited data on outcomes of mechanical thrombectomy for pediatric stroke using modern devices. In this study, we report two cases of pediatric acute ischemic stroke treated with mechanical thrombectomy, both with good angiographic result (TICI 3) and clinical outcome (no neurological deficits at 90 days). In addition, we conducted a literature review of all previously reported cases describing the use of modern thrombectomy devices. Including our two cases, the aggregate rate of partial or complete vessel recanalization was 100% (22/22), and the aggregate rate of favorable clinical outcome was 91% (20/22). This preliminary evidence suggests that mechanical thrombectomy with modern devices may be a safe and effective treatment option in pediatric patients with acute ischemic stroke. Disclosures T. Madaelil: None. A. Kansagra: None. C. Derdeyn: None. D. Cross: None. C. Moran: 2; C; Medtronic Neurovascular.

Background and purpose Flow diversion is an established technique to treat unruptured intracranial aneurysms not amenable to standard endovascular or microsurgical techniques. The suitability of flow diverting devices (FDD) to treat ruptured aneurysms is less clear. Materials and methods An in-depth search of multiple electronic publication databases was performed for reports describing ruptured intracranial aneurysms treated by flow diversion. Clinical and radiological characteristics, interventional details, and outcomes were pooled and analyzed in aggregate. Results The pooled cohort comprised of 126 patients with a mean age of 52.6 ± 12.5 years. Mean Hunt Hess/World Federation of Neurosurgical Societies grading scale at presentation was 2.2 ± 1.2. Treated aneurysms were located in the anterior circulation in 64% (81/126) cases and 36% (45/126) in the posterior circulation. Five distinct aneurysm morphologies were present, including dissecting (28%, 35/125), fusiform (9.6%, 12/125), giant (3.2%, 4/125), blister (37.6%, 47/125), and saccular (21.6%, 27/125) types. Favorable clinical outcome (defined as Modified Rankin Scale (mRS) = 0−2 or Glasgow Outcome Scale (GOS) = 4−5) was achieved in 81.5% (101/124) of treated patients. Unfavorable clinic outcome (defined by mRS = 3−6 or GOS = 1−3) occurred in 18.5% (23/124) of patients. Clinically significant hemorrhagic complications occurred in 5.5% (7/126) of cases, the majority of which were due to aneurysm re-rupture (4.8%; 6/126). Aneurysm size greater than 2cm was associated with a greater risk of re-rupture when compared to aneurysms smaller than 2 cm (p = 0.001). Aneurysm size greater than 7 mm was associated with more unfavorable clinical outcomes (p = 0.03). Conclusion For ruptured aneurysms not amenable to other treatment strategies, the use of flow diversion may allow for reasonably high rates of good clinical outcomes, particularly in small aneurysms. There was a risk of re-rupture in these aneurysms, especially those larger than 2 cm. Disclosures T. Madaelil: None. C. Moran: 2; C; Medtronic Neurovascular. D. Cross: None. A. Kansagra: None.

Interventional neuroradiology continues to play an increasing role in the treatment of intracranial aneurysms, the treatment of vasospasm related to subarachnoid hemorrhage, and the treatment of vascular malformations and fistulae of the brain and spine. New techniques for aneurysm embolization are examined, such as detachable coil systems, as are reports of intracranial angioplasty and superselective papaverine infusion for vasospasm following aneurysm rupture. Results of investigations of arteriovenous malformation embolizations and recent analyses of risk factors associated with arteriovenous malformations are discussed. New approaches to tumor embolization are presented, and there are new data on angioplasty for cerebral atherosclerotic disease. Local fibrinolytic therapy in the treatment of patients with acute intracranial arterial or venous sinus thrombosis is evaluated.

Object. The goal of this study was to determine whether a hospital's volume of subarachnoid hemorrhage (SAH) cases affects mortality rates in patients with SAH. For certain serious illnesses and surgical procedures, outcome has been associated with hospital case volume. Subarachnoid hemorrhage, usually resulting from a ruptured cerebral aneurysm, yields a high mortality rate. There has been no multistate study of a diverse set of hospitals to determine whether in-hospital mortality rates are influenced by hospital volume of SAH cases. Methods. The authors conducted an analysis of a retrospective, administrative database of 16,399 hospitalizations for SAH (9290 admitted through emergency departments). These hospitalizations were from acute-care hospitals in 18 states representing 58% of the US population. Both univariate and multivariate analyses were used to assess the case volume—mortality rate relationship. The authors used patient age, sex, Medicaid status, hospital region, data source year, hospital case volume quartile, and a comorbidity index in multivariate generalized estimating equations to model the relationship between hospital volume and mortality rates after SAH. Patients with SAH who were treated in hospitals in which low volumes of patients with SAH are admitted through the emergency department had 1.4 times the odds of dying in the hospital (95% confidence interval 1.2–1.6) as patients admitted to high-volume hospitals after controlling for patient age, sex, Medicaid status, hospital region, database year, and comorbid conditions. Conclusions. Patients with a diagnosis of SAH on their discharge records who initially presented through the emergency department of a hospital with a high volume of SAH cases had significantly lower mortality rates. Concentrating care for this disease in high-volume SAH treatment centers may improve overall survival.

Summary: This case illustrates rapid aneurysm enlargement, presumably due to altered hemodynamics resulting from endovascular treatment of aneurysms on the same artery. We postulate that increased hemodynamic force directed to the inflow zone of the posterior communicating artery aneurysm was caused by the treatment of the two ophthalmic artery aneurysms. Originally, many of the flow vectors may have been directed into the larger ophthalmic segment aneurysm, located on the outside of the curve of the internal carotid artery. After treatment, flow may have been directed more smoothly around the carotid siphon and into the posterior communicating artery aneurysm.

BACKGROUND AND PURPOSE: Fibrinolysis with local intraarterial urokinase infusion for basilar artery thrombosis has been associated with a low rate of spontaneous symptomatic cerebral hemorrhage, even when patients have been treated late in the course of symptoms. Because urokinase is presently unavailable in the United States, this study was undertaken to determine the frequency of spontaneous cerebral hemorrhage in basilar artery fibrinolysis performed with tissue plasminogen activator (tPA). METHODS: In a retrospective review of our initial experience with cerebral fibrinolysis for acute stroke using intraarterial tPA, four cases of basilar thrombosis were identified. Doses of the fibrinolytic agent and heparin, angiographic findings, clinical courses, and bleeding complications for these patients were determined. These results were compared with those from a prior study of 20 similar consecutive patients treated with urokinase. RESULTS: Symptom duration before treatment was unlimited. Intraarterial doses of tPA were 20 to 50 mg. Patients received full systemic anticoagulation with heparin. Complete basilar artery recanalization was achieved in 75% of patients. Two patients treated with tPA had angioplasty and stent placement for related high-grade stenosis. Spontaneous symptomatic cerebral hemorrhage occurred in three (75%) of the four tPA-treated patients and in three (15%) of the 20 urokinase-treated patients. CONCLUSION: The cerebral hemorrhage complication rate for intraarterial fibrinolysis with tPA was very high in cases of basilar artery thrombosis at the doses we used. Protocol adjustments should be considered.

We sought to identify the initial MR findings of herpes simplex encephalitis in infants and young children.MR imaging findings of herpes encephalitis in infants and young children appear to differ from those seen in neonates, older children, and adults. Appreciation of this MR imaging pattern coupled with a strong clinical suspicion of herpes helps to ensure the correct diagnosis is made.

BACKGROUND AND PURPOSE: This study was undertaken to examine the relationship between collateral flow and outcome after local intraarterial thrombolytic treatment for basilar artery thrombosis. METHODS: Twenty-four patients with symptomatic basilar thrombosis were treated with intraarterial urokinase. Angiograms at the time of treatment were analyzed to characterize collateral flow. The number of posterior communicating arteries (PCoAs) and the degree of collateral filling of the basilar artery were then compared with symptom duration before treatment, with Glasgow Coma Scale (GCS) score at the time of treatment, with 90-day modified Rankin score, and with 90-day survival status. RESULTS: Of the 20 patients who had carotid artery injections at the time of the thrombolytic procedure, two had no PCoA, eight had one PCoA, and 10 had two PCoAs. Nine had no collateral opacification of the basilar artery, six had collateral opacification of the distal basilar artery, and five had collateral opacification of the distal and proximal basilar artery. Ninety-day survival was 38%; 25% of patients had good neurologic outcomes. No correlation was found between the number of PCoAs and symptom duration, pretreatment GCS score, survival, or neurologic outcome. Duration of symptoms before treatment was longer in patients with collateral flow to the basilar artery. Basilar artery collateral flow did not correlate with survival, but it did correlate with neurologic outcome for the 12 patients with middle or distal basilar artery thrombus in whom collateral flow to the basilar artery was assessed (83% with collateral flow had good neurologic outcomes, but only 17% without collateral flow had good outcomes). All six patients with proximal basilar artery thrombus in whom collateral flow was assessed died, independent of the collateral flow observed. CONCLUSION: In symptomatic acute basilar artery thrombosis, neurologic outcome was better after intraarterial thrombolysis in patients who had collateral filling of the basilar artery, except in cases of proximal basilar thrombosis. Patients with collateral filling of the basilar artery also tolerated longer symptom duration.

PURPOSE: Intraarterial papaverine infusions are performed to reverse cerebral arterial vasospasm resulting from subarachnoid hemorrhage, but such infusions may lead to increases in intracranial pressure (ICP). This study was undertaken to determine when ICP monitoring is indicated during papaverine treatment. METHODS: Seventy-eight vessels were treated in 51 sessions in 28 patients with symptomatic vasospasm. ICP, papaverine doses, and infusion rates were recorded during treatment sessions. The procedural data, Hunt and Hess scores, Fisher grades, Glasgow Coma Scale scores, and ages for all subjects were reviewed and analyzed retrospectively. RESULTS: Baseline ICP ranged from 0 to 34 mm Hg. With typical papaverine doses of 300 mg per territory and infusion times ranging from 5 to 60 minutes per vessel, ICP increases above baseline during papaverine infusion ranged from 0 to 60 mm Hg. Significant (> or = 20 mm Hg) ICP increases during therapy were observed even in patients with low baseline ICP and with papaverine infused at the slowest rate. Patients with a baseline ICP of more than 15 mm Hg were much more likely to have significant ICP increases than were patients with a baseline ICP of 0 to 15 mm Hg. Hunt and Hess scores, Fisher grades, age, and Glasgow Coma Scale scores on admission and immediately before treatment did not correlate with ICP increases during papaverine infusion. Patients with ICP increases of more than 10 mm Hg during therapy were more likely to experience adverse clinical events than were patients with ICP increases of < or = 10 mm Hg. Reduction in the rate of papaverine infusion, or termination of infusion, resulted in reversal of drug-induced ICP elevation. CONCLUSION: ICP monitoring during intraarterial papaverine infusions for cerebral vasospasm is recommended for all patients and is particularly important for patients with elevated baseline ICP. Continuous ICP monitoring facilitates safe and time-efficient drug delivery.

To correlate the size and location of intracranial aneurysm with the need to reposition the aneurysm clip after intraoperative angiography.In 199 consecutive patients with 234 clipped intracranial aneurysms, 273 intraoperative angiographic studies were retrospectively reviewed. Aneurysm size and location, determined with preoperative angiographic and surgical reports, were correlated with the frequency of clip repositioning because of parent- or branch-vessel compromise or unexpected residual aneurysm.Findings from intraoperative angiograms resulted in clip repositioning in 46 of 273 (16.8%) studies. Clip repositioning was statistically significantly less frequent with aneurysms of the posterior communicating (three of 52 [5.7%] studies) and anterior choroidal (none of 12 studies) arteries. High rates of clip repositioning were found in aneurysms of the superior hypophyseal artery (seven of 18 [38.9%] studies), superior cerebellar artery (three of five [60.0%] studies), and bifurcation of the internal carotid artery (three of nine [33.3%] aneurysms). In 98 conventional follow-up angiographic studies, seven (7%) false-negative cases with unsuspected aneurysm neck remnant were found.The rate of clip repositioning in aneurysms of the posterior communicating or anterior choroidal arteries was less than that at other locations (P.05). Intraoperative angiography may not be necessary when aneurysms are at these two locations.

PURPOSE: To identify factors that predict survival and good neurologic outcome in patients undergoing basilar artery thrombolysis. METHODS: Over a 42-month period, 20 of 22 consecutive patients with angiographic proof of basilar artery thrombosis were treated with local intraarterial urokinase. Brain CT scans, neurologic examinations, symptom duration, clot location, and degree of recanalization were analyzed retrospectively. RESULTS: Overall survival was 35% at 3 months. Survival in patients with only distal basilar clot was 71%, while survival in patients with proximal or midbasilar clot was only 15%. At 3 months, 29% of patients with distal basilar clot and 15% of patients with proximal or midbasilar clot had good neurologic outcomes (modified Rankin score of 0 to 2 and Barthel index of 95 to 100). Complete recanalization was achieved in 50% of patients; 60% of those survived and 30% had good neurologic outcomes. Of patients with less than complete recanalization, only 10% survived. Neither duration of symptoms before treatment (range, 1 to 79 hours), age (range, 12 to 83 years), nor neurologic status at the initiation of treatment (Glasgow Coma Scale score range, 3 to 15) predicted outcome. Pretreatment CT findings (positive or negative for related ischemic changes) did not predict outcome or hemorrhagic transformation. CONCLUSION: The single best predictor of survival after basilar thrombosis and intraarterial thrombolysis was distal clot location. Complete recanalization favored survival. Radiologically evident related infarctions, advanced age, delayed diagnosis, and poor pretreatment neurologic status did not predict poor outcome and therefore should not be considered absolute contraindications for intraarterial thrombolysis in patients with basilar artery thrombosis.

PURPOSE: To measure the mean cerebral circulation time (CCT) in patients with symptomatic vasospasm stemming from subarachnoid hemorrhage and to determine any change after papaverine treatment. METHODS: We studied 27 patients who received intraarterial papaverine from November 1992 to August 1995 to determine the CCT in 59 carotid territories. CCT was measured from the first image in which contrast was seen above the supraclinoid internal carotid artery to the peak filling of parietal cortical veins. Angiograms at the time of presentation were examined in 19 of the 27 patients. A control population of 19 patients (30 carotid territories) was also studied. RESULTS: The mean CCT on presentation was 6.8 seconds +/- 1.1. The prepapaverine mean CCT was 6.1 seconds +/- 1.2. The immediate postpapaverine mean CCT was 3.8 seconds +/- 0.8. CCT decreased in 58 of 59 territories treated with papaverine; the mean change was -35.7%. In eight of these patients, CCT rose on the following day to 6.1 seconds +/- 1.1. In the control group, mean CCT was 5.9 seconds +/- 0.8. The mean CCT in patients with subarachnoid hemorrhage was slightly prolonged on presentation relative to that in control subjects. CONCLUSION: Intraarterial papaverine produces a consistent decrease in CCT in patients with vasospasm.

While performing carotid angiography in a 76-year-old man, we found that the right internal carotid artery repeatedly opened and closed during the examination. The patient experienced no related neurologic events. The explanation, confirmed at surgery, was that a flap associated with an atherosclerotic plaque had acted as a ball valve.

Thrombosis of the superior sagittal sinus may result in significant morbidity and recently up to 20% mortality. Primary treatment has consisted of anticoagulation and methods for controlling increased intracranial pressure. The development of interventional neuroradiologic techniques has enabled infusion of thrombolytics at the clot. We describe a woman with a cerebral haemorrhage due to a thrombosed superior sagittal sinus. Her decreased level of consciousness and increasing hemiparesis prompted direct thrombolytic therapy (urokinase). Flow was restored in the occluded sinus, but an acute expansion of the haematoma an hour after conclusion of the infusion resulted in temporary worsening of her neurologic deficits. Although the ultimate outcome was satisfactory, the possibility of further intracranial bleeding must be balanced against the risk of death with conservative therapy.

A 31-year-old man with pulmonary tuberculosis who did not have human immunodeficiency virus had massive epistaxis from a giant petrous internal carotid artery pseudoaneurysm. Endovascular trapping of the aneurysm was performed, curing the epistaxis. MR showed multiple enhancing brain lesions that resolved with additional antituberculous drug therapy.

Purpose Intracranial arterial stenosis is one cause of ischemic stroke. A two-step procedure using one specific angioplasty balloon (Gateway®) and one specific self-expanding stent (Wingspan®) was inferior to best medical management in a recent trial (SAMMPRIS), partly due to a greater than expected complication rate in its interventional arm. There are other devices that can be used to dilate stenotic cerebral arteries in a one-step approach. If complications are fewer and long-term results are favorable, treatment by dilation with such devices may achieve superiority over best medical management in patients who are medically refractory. Drug-eluting balloon-mounted stents (DES) can be deployed in a one-stage procedure in stenotic intracranial arteries and are less prone to re-stenosis than bare-metal stents, though there is some concern about late in-stent thrombosis. Long-term outcomes of intracranial DES treatment have not been previously studied. We report the long-term follow-up of 10 patients treated with DES for symptomatic intracranial arterial stenosis refractory to medical management. Methods From 2003 to 2007, 10 patients (mean age, 58.9 years) with intracranial arterial stenosis that remained symptomatic (recurrent TIA or stroke) despite medical therapy were treated with DES. Twelve Cipher balloon-expandable stents were deployed, with 2 of the 10 patients receiving two stents each due to the presence of multiple high-grade lesions. Four lesions required pre-dilation with balloon angioplasty using the Maverick® system. Medical records were reviewed for demographic information, procedural details, complications, and follow-up imaging results. Telephone interviews were performed in August, 2011, to assess for new stroke or TIA, disability according to the modified Rankin Scale (mRS), and compliance with anti-platelet medications. Results Stenotic lesions were located in the internal carotid artery in six patients, the middle cerebral artery in one patient, the vertebral artery in two patients, and both a vertebral artery and the basilar artery in one patient. All 12 stents were successfully deployed. A mean stenosis of 81.5±13.3% was reduced to 7.1±16.3%. In 1 patient with 99% stenosis of the left ICA, the lesion could not be reduced to Conclusion The safety and long-term efficacy of DES in preventing recurrent stroke in symptomatic patients with high-grade intracranial arterial stenosis who are refractory to medical management is promising and should encourage further study of that intervention for that patient subgroup. Competing interests R Gottumukkala: None. Y Kadkhodayan: None. A Mazumdar: None. C Moran: EV3, Stryker, Codman. C Derdeyn: W.L Gore and Associates. nFocus, Pulse therapeutics. D Cross: None.

We identified 53 patients with non-neoplastic cysts of the pineal gland. In contrast to patients with pineal neoplasms, pineal cysts are usually asymptomatic. They infrequently obstruct the aqueduct to cause hydrocephalus or compress the tectum to produce the neuro-ophthalmologic signs of dorsal midbrain dysfunction. Obstructive hydrocephalus was present in only five patients (9.4%); three of them showed clinical signs of Parinaud's syndrome. CT and MRI typically reveal a cystic mass that averages 1.6 cm in anteroposterior (A-P) diameter with calcification at the periphery and faint rim-like contrast enhancement. Sagittal MRI is the most useful diagnostic test because it shows the anatomic relationship of the cyst to the aqueduct. The mass may compress the tectum and distort the proximal aqueduct; occasionally a large cyst may occlude the aqueduct. All patients with obstructive hydrocephalus had cysts greater than 2.0 cm in A-P diameter. Nine patients had suboccipital craniotomy. In all of them, the cysts contained clear fluid and were easily removed. We advocate conservative management with clinical observation of these benign lesions that may be developmental variants of normal pineal gland.

Uterine contractions in 8 nonpregnant and 13 pregnant mares were studied using ultrasonography. A 1-min video tape recording was made of longitudinal real-time images of the uterine body. An overall uterine contractile activity score (0 = no or minimal activity to 4 = maximal activity) was assigned to each video tape segment. There was a day effect (P less than .01) and an interaction (P less than .01) of reproductive status X day. Uterine activity scores were highest on d 14 to d 18 (d 0 = day of ovulation) for nonpregnant mares and on d 10 to d 14 for pregnant mares. Uterine activity scores on d 10, d 12, and d 14 were greater (P less than .02) for pregnant mares (2.5 +/- .3, 3.1 +/- .3, and 3.2 +/- .1, respectively) than for nonpregnant mares (1.2 +/- .3, 1.5 +/- .3, and 2.6 +/- .3). Uterine activity scores for six pregnant and five nonbred jennies were assigned daily from d 0 to d 24. There were main effects of reproductive status and day (P less than .01) and an interaction of status X day (P less than .01). Uterine activity scores for pregnant jennies were highest on d 13 and d 14 and then declined. In the nonbred jennies, scores were highest on d 14 to d 20. The mean score on d 13 was greater (P = .05) in pregnant jennies (2.8 +/- .2) than in nonbred jennies (1.9 +/- .5).(ABSTRACT TRUNCATED AT 250 WORDS)

Uterine contractions in 8 nonpregnant and 13 pregnant mares were studied using ultrasonography. A 1-min video tape recording was made of longitudinal real-time images of the uterine body. An overall uterine contractile activity score (0 = no or minimal activity to 4 = maximal activity) was assigned to each video tape segment. There was a day effect (P less than .01) and an interaction (P less than .01) of reproductive status X day. Uterine activity scores were highest on d 14 to d 18 (d 0 = day of ovulation) for nonpregnant mares and on d 10 to d 14 for pregnant mares. Uterine activity scores on d 10, d 12, and d 14 were greater (P less than .02) for pregnant mares (2.5 +/- .3, 3.1 +/- .3, and 3.2 +/- .1, respectively) than for nonpregnant mares (1.2 +/- .3, 1.5 +/- .3, and 2.6 +/- .3). Uterine activity scores for six pregnant and five nonbred jennies were assigned daily from d 0 to d 24. There were main effects of reproductive status and day (P less than .01) and an interaction of status X day (P less than .01). Uterine activity scores for pregnant jennies were highest on d 13 and d 14 and then declined. In the nonbred jennies, scores were highest on d 14 to d 20. The mean score on d 13 was greater (P = .05) in pregnant jennies (2.8 +/- .2) than in nonbred jennies (1.9 +/- .5).(ABSTRACT TRUNCATED AT 250 WORDS)

To evaluate Doppler ultrasound (US) as a screening modality before arteriography for extracranial carotid artery disease.The net benefit in stroke reduction from screening with Doppler US was calculated on the basis of literature estimates of disease prevalence, risk reduction data, and locally validated sensitivities and specificities for detection of carotid artery stenosis and occlusion in 215 patients.Screening a symptomatic population demonstrated a net stroke reduction. Screening asymptomatic populations with a 20% prevalence ofor = 60% stenosis also yielded a net stroke reduction. Screening low-prevalence (5%) asymptomatic populations produced a small benefit, which was lost if arteriographic or surgical complications increased slightly. Arteriographic confirmation of the US diagnosis of occlusion produced a small benefit only in the symptomatic population.Screening symptomatic and high-prevalence asymptomatic populations with US reduces stroke. Increased arteriographic or surgical complication rates reduce the benefit of screening in any population.