Biomedical subjects

M C Wallace

Publications and source records attributed to M C Wallace.

At least 55 records · Page 3Linked to original sources

PubMed1997

Quality of life of stroke in younger individuals. Utility assessment in patients with arteriovenous malformations.

BACKGROUND AND PURPOSE: Patients with arteriovenous malformations are younger individuals who are at risk of a stroke or have experienced one. Our objective was to determine these patients' perceptions of quality of life with a stroke by eliciting utility values. METHODS: Utility values were obtained with the standard gamble technique. Utilities are a holistic, quality of life measure between 0 and 1. We evaluated the patients' current health state and written descriptions of major and minor stroke. RESULTS: Thirty-one consecutive outpatients participated. The mean age was 37 years (range, 18 to 57 years). Approximately 65% had suffered a stroke, of which 55% were major. Approximately 61% had a persistent deficit. The mean utilities were 0.45 for major stroke (95% confidence interval [CI], 0.33 to 0.56; range, 0.00 to 1.00), 0.81 for minor stroke (95% CI, 0.75 to 0.88; range, 0.30 to 1.00), and 0.81 for current health (95% CI, 0.73 to 0.89; range, 0.01 to 1.00). Subgroup analyses by demographic and clinical characteristics showed no significant differences. However, in both those patients who had never had a stroke and those who had survived a major stroke, values for the major stroke scenario were clustered at the two extremes. Among those with a current deficit, 79% preferred their own health state to that of the stroke scenario that was similar in severity. CONCLUSIONS: Younger people who have had a stroke or are at risk demonstrate wide variations in their perception of quality of life. Furthermore, patients tend to be more risk averse with their own lives than with theoretical scenarios. We suggest tailoring medical decision making to individual preferences.

Adolescent↗

PubMed1997

Multilevel anterior cervical corpectomy and fibular allograft fusion for cervical myelopathy.

This study was conducted to determine the safety and efficacy of multilevel anterior cervical corpectomy and stabilization using fibular allograft in patients with cervical myelopathy. Thirty-six patients underwent this procedure for cervical myelopathy caused by spondylosis (20 patients), ossified posterior longitudinal ligament (four patients), trauma (one patient), or a combination of lesions (11 patients). The mean age (+/- standard deviation) of the patients was 58 +/- 10 years and 30 of the patients were men. The mean duration of symptoms before surgery was 30 +/- 6 months and 11 patients had undergone previous surgery. Prior to surgery, the mean Nurick grade of the myelopathy was 3.1 +/- 1.4. Seventeen patients also had cervicobrachial pain. Four vertebrae were removed in six patients, three in 19, and two in 11 patients. Instrumentation was used in 15 cases. The operative mortality rate was 3% (one patient) and two patients died 2 months postoperatively. Postoperative complications included early graft displacement requiring reoperation (three patients), transient dysphagia (two patients), cerebrospinal fluid leak treated by lumbar drainage (three patients), myocardial infarction (two patients), and late graft fracture (one patient). One patient developed transient worsening of myelopathy and three developed new, temporary radiculopathies. All patients achieved stable bone union and the mean Nurick grade at an average of 31 +/- 20 months (range 0-79 months) postoperatively was 2.4 +/- 1.6 (p < 0.05, t-test). Cervicobrachial pain improved in 10 (59%) of the 17 patients who had preoperative pain and myelopathy improved at least one grade in 17 patients (47%; p < 0.05). Twenty-six surviving patients (72%) were followed for more than 24 months and stable, osseous union occurred in 97%. These results show that extensive, multilevel anterior decompression and stabilization using fibular allograft can be achieved with a perioperative mortality and major morbidity rate of 22% and with significant improvement in pain and myelopathy.

Aged↗

PubMed1997

Cerebral cavernous malformations: natural history and prognosis after clinical deterioration with or without hemorrhage.

Despite recent studies of the natural history of cavernous malformations, there remains significant uncertainty concerning hemorrhage rates and the importance of lesion location. Controversy arises over varying definitions of "hemorrhage." What is ultimately important to the patient is the occurrence of a neurological event, which may or may not be associated with radiologically documented hemorrhage, as well as the chance of recovery after such an event. The purpose of this study was to determine the rates of occurrence and sequelae of neurological events in 173 patients referred to our vascular malformation clinic with cavernous malformations. All patient data were entered into a database. The mean age at presentation for the 173 patients was 37.5 years. The lesion location was deep (brainstem, cerebellar nuclei, thalamus, or basal ganglia) in 64 patients (37%) and superficial in 109 (63%). Thirty-one patients (18%) had multiple lesions. Disease presentation was due to seizures in 62 patients (36%), hemorrhage in 44 (25%), focal neurological deficit without documented hemorrhage in 35 (20%), headache alone in 11 (6%), and incidental findings in 21 patients (12%). The results obtained in the 110 patients eligible for follow-up review were used to derive information on the rates of hemorrhage and neurological events. An interval event (neurological deterioration) required both symptoms and signs. The total mean follow-up period was 46 months, the majority (65%) of which was prospective. There were 18 interval events in 427 patient-years of follow-up review, for an overall annual event rate of 4.2%. Location was the most important factor for predicting interval event occurrence, with significantly higher rates for deeply located (10.6%/year) compared with superficially located lesions (0%/year) (p = 0.0001). Of patients suffering a neurological event, only 37% had complete resolution of their deficits. This largely prospective study indicates that deep cavernous malformations carry a worse prognosis than superficial lesions with respect to annual rates of neurological deterioration. The alarming rate of adverse clinical events occurring in patients with deep lesions is punctuated by the fact that less than one-half of them recover fully during long-term follow-up review.

Adult↗

PubMed1997

Spinal epidural arteriovenous fistula with intramedullary reflux. Case report.

A spinal epidural arteriovenous fistula with secondary reflux into the perimedullary veins is a rare entity. The authors present such a case with a discussion of its pathophysiology and treatment. The mechanism for formation of a spinal dural arteriovenous fistula is outlined based on the anatomical substrates in this region.

Aged↗

PubMed1996

Cerebral ischemia alters the regional hippocampal expression of the rat m1 muscarinic acetylcholine receptor gene.

We investigated the dynamics of the gene expression of the m1 subtype of muscarinic cholinergic receptor in the rat hippocampus following transient global ischemia. This receptor represents the dominant phosphoinositide linked muscarinic receptor in the hippocampus, and is recognized to modulate various aspects of neuronal activity in the hippocampus. Our results demonstrate that following severe transient global ischemia, m1 receptor expression is altered in the hippocampus in a time dependent manner. Expression levels declined in the dentate gyrus within 3 h of insult, reached minimal levels by 6 h, and then slowly recover to control levels. Expression levels in the CA1 and CA3 decreased as well, but did not reach minimal levels until 24 h post-insult. By day 3, expression levels in all regions except CA1, where vulnerable neurons began to drop out, had returned to control levels. These results demonstrate that transient alterations in the gene expression levels for the m1 muscarinic receptor occur in all subfields of the hippocampus following transient forebrain ischemia.

Animals↗

PubMed1996

Accumulation and extrusion of permeant Ca2+ chelators in attenuation of synaptic transmission at hippocampal CA1 neurons.

The effects of extracellularly applied membrane-permeant Ca2+ chelators on field excitatory postsynaptic potentials were determined in the hippocampal CA1 region of rat brain slices. Field excitatory postsynaptic potentials in slices perfused with 0.05-50 microM bis-(-O-aminophenoxy)-ethane-N,N,N,N,-tetraacetic acid acetoxymethyl (BAPTA-AM) for 15 min were reversibly attenuated by 10-45% in a concentration-dependent manner. Attenuation occurred earlier at higher concentrations of BAPTA-AM, thus indicating that the rate of accumulation of BAPTA salt was concentration dependent. Antidromically evoked responses and presynaptic volleys were unaffected by BAPTA-AM. Attenuation of the field excitatory postsynaptic potentials by BAPTA-AM was temporarily eliminated by repetitive stimulation at 1 Hz, suggesting saturation of the chelator's Ca(2+)-binding capacity. The amplitude of field excitatory postsynaptic potentials was unaffected by similar applications of 5'5-dinitro-BAPTA-AM, a low Ca(2+)-affinity BAPTA analogue, and EGTA-AM (5 or 50 microM), a chelator with slow Ca(2+)-binding kinetics, suggesting a dependence of the BAPTA-AM effect on fast Ca2+ binding and high Ca2+ affinity. BAPTA-AM concentrations as low as 0.05 microM were effective provided application was prolonged to 40 min. Probenecid (1 mM), an anion transport inhibitor, accelerated the onset and significantly enhanced the BAPTA-mediated synaptic attenuation caused by low concentrations of BAPTA-AM. These data show that even very low extracellular concentrations of BAPTA-AM can profoundly affect synaptic transmission provided that sufficient chelator accumulates presynaptically. The effectiveness of BAPTA-AM can be increased by procedures which inhibit chelator extrusion.

Animals↗

PubMed1996

The validity of classification for the clinical presentation of intracranial dural arteriovenous fistulas.

A number of classification schemes for intracranial dural arteriovenous fistulas (AVFs) have been published that claim to predict which lesions will present in a benign or aggressive fashion based on radiological anatomy. We have tested the validity of two proposed classification schemes for the first time in a large single-institution study. A series of 102 intracranial dural AVFs in 98 patients assessed at a single institution was analyzed. All patients were classified according to two grading scales: the more descriptive schema of Cognard, et al. (Cognard) and that recently proposed by Borden, et al. (Borden). According to the Borden classification, 55 patients were Type I, 18 Type II, and 29 Type III. Using the Cognard classification, 40 patients were Type I, 15 Type IIA, eight Type IIB, 10 Type IIA+B, 13 Type III, 12 Type IV, and four Type V. Intracranial hemorrhage (ICH) or nonhemorrhagic neurological deficit was considered an aggressive presenting clinical feature. A total of 16 (16%) of 102 intracranial dural AVFs presented with hemorrhage. Eleven of these hemorrhages (69%) occurred in either anterior cranial fossa or tentorial lesions. When analyzed according to the Borden classification, none (0%) of 55 Type I intracranial dural AVFs, two (11%) of 18 Type II, and 14 (48%) of 29 Type III intracranial dural AVFs presented with hemorrhage (p < 0.0001). After exclusion of visual or cranial nerve deficits that were clearly related to cavernous sinus intracranial dural AVFs, nonhemorrhagic neurological deficits were a feature of presentation in one (2%) of 55 Type I, five (28%) of 18 Type II, and nine (31%) of 29 Type III patients (p < 0.0001). When combined, an aggressive clinical presentation (ICH or nonhemorrhagic neurological deficit) was seen most commonly in intracranial dural AVFs located in the tentorium (11 (79%) of 14) and the anterior cranial fossa (three (75%) of four), but this simply reflected the number of higher grade lesions in these locations. Aggressive clinical presentation strongly correlated with Borden types: one (2%) of 55 Type I, seven (39%) of 18 Type II, and 23 (79%) of 29 Type III patients (p < 0.0001). A similar correlation with aggressive presentation was seen with the Cognard classification: none (0%) of 40 Type I, one (7%) of 15 Type IIA, three (38%) of eight Type IIB, four (40%) of 10 Type IIA+B, nine (69%) of 13 Type III, 10 (83%) of 12 Type IV, and four (100%) of four Type V (p < 0.0001). No location is immune from harboring lesions capable of an aggressive presentation. Location itself only raises the index of suspicion for dangerous venous anatomy in some intracranial dural AVFs. The configuration of venous anatomy as reflected by both the Cognard and Borden classifications strongly predicts intracranial dural AVFs that will present with ICH or nonhemorrhagic neurological deficit.

Adolescent↗

PubMed1995

C1-C2 posterior cervical fusion: long-term evaluation of results and efficacy.

Posterior wiring techniques are the most commonly used methods of achieving C1-C2 arthrodesis. Recently, transarticular screw fixation and interlaminar clamping have been advocated to achieve more secure fixation. A retrospective review of patients undergoing C1-C2 fusion for nonneoplastic disease was undertaken at the University of Toronto Hospital, with the aim of determining the long-term outcome of the selected procedures. Thirty-two patients underwent 36 procedures from 1986 to 1992, with a mean follow-up of 4.7 +/- 2.2 years (range, 2.0-8.0 yr). The most common disease processes were odontoid fracture (18 patients), transverse atlantal ligament injury (5 patients), os odontoideum (5 patients), and rheumatoid C1-C2 instability (3 patients). Thirty-one Gallie fusions, one Brooks-Jenkins fusion, two transarticular screw fusions, and two Halifax clamp applications were performed. Six (19%) of Gallie/Brooks-Jenkins fusions failed. These occurred with os odontoideum (three patients), Type II odontoid fracture (two patients), and transverse atlantal ligament injury (one patient). All transarticular screw and Halifax clamp procedures resulted in successful fusions. Two procedures (6%) resulted in new neurological deficit; both of these patients underwent posterior wiring for os odontoideum. This study suggests that Type II odontoid fractures may be successfully managed by a posterior wiring technique alone. Rheumatoid C1-C2 instability may be managed by posterior wiring supplemented with halo immobilization. Transarticular screw fixation has several potential advantages as a technique for C1-C2 arthrodesis and, in particular, may be appropriate for os odontoideum that had a high failure rate (75%) with conventional posterior wiring, even when this was supplemented with halo bracing.

Adolescent↗

PubMed1995

Neutral red staining for the assessment of acute outcome in rat focal cerebral ischemia models.

Neutral red staining was evaluated as an acute outcome assessment method in rat models of cerebral ischemia by comparison with histological infarction volume. Fischer 344 rats (n = 48) were used in three different models of middle cerebral artery (MCA) occlusion: proximal MCA occlusion (n = 16), distal MCA occlusion followed by ipsilateral common carotid artery (CCA) occlusion (distal MCA/CCA occlusion, n = 15), and MCA occlusion with an intravascularly introduced 4-0 nylon suture (intravascular MCA occlusion, n = 17). At 1 hour, 2 hours, and 4 hours after MCA occlusion, animals were injected with 2.5 ml of 4% neutral red solution via the femoral vein, and then sacrificed. Proximal MCA occlusion caused a neutral red defect volume in the cortex which correlated well with histological infarction volume at 4 hours (r = 0.88, p < 0.05), and in the caudate which correlated well with infarction volume at 4 hours (r = 0.94, p < 0.01). Distal MCA/CCA occlusion caused a neutral red defect volume in the cortex lager than the histological infarction volume (4 hrs: 88.6 +/- 11.8 vs. 74.3 +/- 17.4 mm3, p < 0.05) but closely correlated with the infarction volume at 4 hours (r = 0.81, p < 0.05). Intravascular MCA occlusion caused a neutral red defect volume in only two of 17 animals after 1-4 hours, which correlated well with the absence of histological evidence of infarction. Neutral red staining is a simple method for assessing the acute outcome of focal cerebral ischemia as early as 4 hours after the onset, in an appropriate model of cerebral ischemia.

Animals↗

PubMed1995

Pathological effects of angioplasty on vasospastic carotid arteries in a rabbit model.

To define the pathological effects of angioplasty on vasospastic arteries, 36 rabbits underwent angiography and induction of vasospasm by placement of blood-filled (vasospasm groups) or empty (control group) silastic sheaths around the cervical carotid arteries. Two (Day 2) or 7 days (Day 7) later, angiography was repeated and one carotid artery in each animal was dilated by balloon angioplasty. The rabbits were sacrificed 1 day, 7 days, or 3 to 4 weeks after angioplasty. Significant vasospasm developed after placement of silastic sheaths with blood (mean reductions in diameter 39% +/- 6% at Day 2 and 48% +/- 5% at Day 7). Arterial narrowing was less apparent in the control groups at Day 2 (24% +/- 7%). Angioplasty performed on Day 2 significantly increased arterial diameters of vasospastic arteries (50% +/- 7%; p < 0.05) but not those of control arteries (10% +/- 6%, p > 0.05). Angioplasty performed on Day 7 increased the arterial diameters by a similar degree (47% +/- 13%, not significant). Arteries remained dilated after angioplasty, although there was significant vasospasm 7 days after angioplasty when angioplasty was performed on Day 2. Blinded, semiquantitative histopathological study of the arteries showed that 3 to 4 weeks after angioplasty, there was significant endothelial proliferation and a trend for thinning of the tunica media. There were no significant changes in control arteries subjected to angioplasty. Angioplasty was not associated with significant arterial fibrosis as measured by hydroxyproline content (analysis of variance). The increase in endothelial proliferation and decrease in the thickness of the tunica media suggest that, in the rabbit model, angioplasty damages endothelial and smooth-muscle cells. This may be the basis for the observation that vasospastic arteries do not reconstrict after angioplasty.

Analysis of Variance↗

PubMed1994

Bilateral third cranial nerve palsies in association with a ruptured anterior communicating artery aneurysm.

Third cranial nerve palsy occurring in a patient with an intracranial aneurysm is typically unilateral and associated with an internal carotid-posterior communicating or distal basilar artery aneurysm. In this report a patient with bilateral third cranial nerve palsies associated with rupture of an anterior communicating artery aneurysm is described. Raised intracranial pressure without brain herniation and compression of the third nerves within the perimesencephalic cisterns by focal subarachnoid clot are suggested as possible underlying mechanisms of the palsies, which showed complete recovery at 4 months after the hemorrhage and subsequent early aneurysm repair.

Carotid Artery, Internal↗

PubMed1994

Surgical referral for carotid artery stenosis--the influence of NASCET. North American Symptomatic Carotid Endarterectomy Trial.

A retrospective review was undertaken of 139 consecutive patients with presumed carotid artery stenosis referred to a vascular neurosurgeon. The review period included three years prior and one year subsequent to the publication of the North American Symptomatic Carotid Endarterectomy Trial (NASCET) preliminary results showing surgery to be superior to best medical therapy for patients with symptomatic, high grade (> 70% linear diameter) carotid stenosis. The aims of this analysis were to determine any changes in the referral pattern following the NASCET publication (post-NASCET), and to examine the use and reliability for surgical decision making of pre-referral carotid artery imaging. Patient referral rate increased markedly post-NASCET, particularly from neurologists. There was a trend for more post-NASCET referrals to be for high grade stenosis and fewer referrals to be for intermediate grade (30-69% linear diameter) stenosis, although continued referral of patients with intermediate grade stenosis is desirable as randomization into NASCET continues for this group of patients. Ninety-six patients (69%) were referred with carotid duplex ultrasonography having been performed. There was poor correlation of these results with angiography, which remains necessary for planning management. A majority of patients (65%) referred to this surgical practice did not come to surgery.

Adult↗

PubMed1994

Mechanism of action and persistence of neuroprotection by cell-permeant Ca2+ chelators.

Cell-permeant Ca2+ chelators such as 1,2-bis-(2-aminophenoxy)ethane- N,N,N',N'-tetraacetic acid acetoxymethyl ester (BAPTA-AM) have been reported to protect neurons in experimental focal cerebral ischemia. However, their in vivo actions are uncertain, and their protective efficacy is proven only in brief cerebral ischemia paradigms. Here we examine their mechanism of action in vitro and duration of efficacy in vivo. Electrophysiological studies were made in CA1 neurons in rat hippocampal slices. When superfused with BAPTA-AM (30-50 microM), CA1 somatic field potential recordings showed attenuation of the population spike amplitude, and intracellular recordings showed reduced excitatory postsynaptic potentials, indicating inhibition of excitatory synaptic transmission. Also, Ca(2+)-dependent accommodation and post-spike-train hyperpolarizations were reduced, indicating Ca2+ chelation hear the internal cell membrane surface. To determine whether Ca2+ chelators reduce the size of cerebral infarction rather than simply delaying its evolution, we studied the effects of BAPTA-AM treatment on infarction size 24 h after permanent middle cerebral artery occlusion. Fischer rats (n = 8 per group) were pretreated with saline, BAPTA-AM (20 mg/kg), or MK-801 (0.5 mg/kg). Infarction volumes in animals treated with BAPTA-AM were reduced by 50.5% compared with controls (p = 0.018), whereas animals treated with MK-801 experienced a statistically insignificant infarct volume reduction (26%; p = 0.27). These data show a persistence of neuroprotection by the Ca2+ chelator at 24 h and indicate that it may act by attenuating synaptic transmission and subplasma membrane Ca2+ excess.

Animals↗

PubMed1994

Peri-operative anticoagulant effects of heparinization for carotid endarterectomy.

The question of whether or not to reverse heparin following carotid endarterectomy is a topic of debate. The potential reduction of the risk of thrombosis at the endarterectomy site with non-reversal has to be measured against a potential increase in the risk of wound haematoma. This study prospectively followed activated clotting time (ACT) of 42 consecutive patients undergoing carotid endarterectomy. A standard heparin dose of 100 units/kg was used, and heparin reversal was employed only if the wound appeared excessively haemorrhagic at the procedure's completion. Heparin was reversed in 11 patients. Following heparin administration, ACT increased to a mean 2.72 +/- 0.09 times baseline (range 1.84-4.07), and fell with time, until at 3 h after heparin administration mean ACT in the non-reversed patients was 1.48 +/- 0.03 times baseline (range 1.1-2.03). There was one postoperative neurological event (2%), a contralateral hemisphere stroke. No patient developed a frank wound haematoma requiring evacuation, although three patients (7% of the total study group, 9% of patients not receiving heparin reversal) developed neck swelling and symptoms of airway compromise, and were intubated. Measurements of ACT suggest that a heparin dose of 100 units/kg achieves an adequate anticoagulant level in the operative and early postoperative phase, when thrombosis is most likely to occur, and is not associated with an increased risk of wound haematoma. If heparin is to be selectively reversed in patients felt to be at high risk of postoperative haematoma, the decision should be based on an objective measurement such as ACT, and not the surgeon's impression of wound haemostasis.

Aged↗

PubMed1994

A novel synapse-associated noncoding RNA.

Synaptic nuclei of innervated muscle transcribe acetylcholine receptor (AChR) genes at a much higher level than extrasynaptic nuclei. To isolate candidate synaptic regulatory molecules responsible for the unique transcriptional potential of synaptic nuclei, we have taken a subtractive hybridization approach. Here, we report the cloning and characterization of a novel synapse-associated RNA, 7H4. 7H4 is expressed selectively in the endplate zone of skeletal muscle and is upregulated during early postnatal development and after denervation. Interestingly, the 7H4 gene has no introns, and yet two different-size RNAs with identical polyadenylated 3' ends are generated. Most intriguingly, the nucleotide sequence does not contain any significant open reading frames, suggesting that 7H4 may function as a noncoding RNA.

Animals↗

PubMed1994

The effect of surgery on the severity of vasospasm.

Intracranial aneurysm surgery performed between 4 and 12 days after subarachnoid hemorrhage (SAH) has been associated with an increased risk of delayed cerebral ischemia and poor outcome compared to surgery performed before or after this time. To investigate whether this increased risk is due to aggravation of vasospasm, the angiograms obtained before and after surgery in 56 patients operated on at various times after aneurysmal SAH were studied. Vasospasm was quantitated by measuring the diameters of intracranial arteries and expressed as the ratio of the diameters of the intracranial arteries to the diameter of the extracranial internal carotid artery. Aggressive surgical clot removal was not performed at surgery. To correct for differences in prognostic factors for vasospasm between patients operated on at different times after SAH, multiple regression analysis was performed using the arterial diameter ratio during vasospasm as the dependent variable and the prognostic factors for vasospasm, including the time of surgery, as independent variables. Equations predicting the severity of vasospasm could be generated using the clinical grade on admission, patient age, and preoperative arterial diameter ratio. The time of surgery had no effect on vasospasm. Cerebral infarction due to vasospasm developed in five (15%) of 34 patients operated on within 3 days after SAH and in four (20%) of 20 operated on between 4 and 12 days after SAH (p = 0.66). A good outcome for these two groups was achieved in 88% and 85%, respectively (p = 1.00). These results suggest that the timing of surgery does not affect the development of vasospasm. Any increased risk of cerebral ischemia associated with surgery performed between 4 and 12 days after SAH is due to factors other than aggravation of vasospasm.

Adult↗

PubMed1994

Rotational angiography assessment of cerebral aneurysms.

PURPOSE: To compare rotational angiography with conventional digital subtraction angiography in the assessment of cerebral aneurysms. METHODS: Conventional digital subtraction angiography and rotational angiography were compared in 57 patients investigated for the preoperative diagnosis of subarachnoid hemorrhage and in 13 patients after surgery. Images were compared for location, visibility of the aneurysmal neck, vascular branch anatomy, projection, size, presence of spasm, and shape of the aneurysm. RESULTS: Rotational angiography was superior to the digital angiogram in assessing aneurysms and vascular anatomy in the following percentage of cases: 12% for location, 46% for the presence of a neck, 32% in the assessment of branch anatomy, 19% for projection, 12% for size, 3.5% for spasm, and 19% for shape. After surgery, rotational angiography more clearly demonstrated the presence or absence of a neck in 69% of the cases. CONCLUSIONS: Rotational angiography often allows better visualization of vascular anatomy and therefore improves the angiographic assessment of aneurysms when compared with conventional digital subtraction angiography, making it an excellent adjunct in the investigation of subarachnoid hemorrhage. The lack of subtraction artifacts from the surgical clips and multiple angles of view also allow better assessment of the presence or absence of a residual neck in postoperative cases.

Angiography, Digital Subtraction↗

PubMed1994

Percutaneous transluminal angioplasty for cerebral vasospasm after subarachnoid hemorrhage.

OBJECTIVE: To assess the efficacy of percutaneous transluminal angioplasty. DESIGN: A retrospective case study covering the period January 1990 to December 1992. SETTING: A tertiary-care referral centre. PATIENTS: Thirteen patients, ranging in age from 23 to 57 years, who had suffered an aneurysmal subarachnoid hemorrhage and subsequent symptomatic vasospasm that had not responded to aggressive medical therapy. INTERVENTION: Percutaneous transluminal angioplasty of spastic cerebral arteries MAIN OUTCOME MEASURES: Neurologic improvement (improved level of consciousness or resolution of focal deficit) immediately after angioplasty and functional status at 6 months after angioplasty. RESULTS: Four (31%) patients showed neurologic improvement immediately after angioplasty. At 6 months, 5 (38%) of the 13 were independent, 2 (15%) were dependent (severely disabled), and 6 (46%) had died. Poor clinical grade at the time of angioplasty was associated with a poor outcome. CONCLUSIONS: Percutaneous transluminal angioplasty appears to be a safe procedure that is beneficial in some patients with symptomatic vasospasm refractory to aggressive hypervolemic, hypertensive therapy. The best results likely are obtained in patients of good clinical grade in whom new neurologic deficits have not become established, and angioplasty should not be delayed if medical therapy does not rapidly reverse the symptoms of vasospasm.

Adult↗