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David G Piepgras

Publications and source records attributed to David G Piepgras.

At least 19 recordsLinked to original sources
PubMed2006

Surgical anatomy of dural defects in spontaneous spinal cerebrospinal fluid leaks.

OBJECTIVE: Spontaneous intracranial hypotension is typically caused by a spontaneous spinal cerebrospinal fluid (CSF) leak. The configuration of the related dural defects can be complex. We describe our experience with the surgical anatomy of these defects. METHODS: Thirteen consecutive patients with spontaneous spinal CSF leaks who underwent surgical exploration at Mayo Clinic between 1994 and 2003 were studied. All patients' records, imaging studies, detailed intraoperative findings, and outcomes were reviewed. RESULTS: There were four men and nine women with an average age of 40 years (range, 12-62 yr). Preoperative imaging studies revealed a single site of CSF leak in eight patients, two sites in three patients, and multiple sites in two patients. Intraoperatively, the exact site of leakage could not be found in four patients. Among the other nine patients, primary closure of a meningeal diverticulum was achieved in one patient. Significant regional attenuation of the dura prevented primary repair of the leak site in eight patients. Muscle, fibrin glue, and Gelfoam (Upjohn Co., Kalamazoo, MI) soaked in patient's own blood were commonly used to pack the epidural space in an attempt to seal the site of the leak. Ligation of two nonappendicular nerve roots allowed closure of the leak in one of these patients. Postoperatively, resolution of symptoms occurred in eight patients, significant improvement was noted in three patients, and only transient resolution in two. The mean duration of follow-up was 20.5 months. CONCLUSION: Surgery for closure of spontaneous spinal CSF leaks may not be straightforward. Even when extradural CSF leakage is discovered preoperatively by imaging studies, it may not always be possible to identify the exact site of the leakage intraoperatively. Furthermore, the anatomy of the dural defects may be complex and not amenable to primary closure. In such cases, the use of adjuvant techniques during surgical exploration may be effective.

Adolescent↗
PubMed2005

Resident duty hours reform: results of a national survey of the program directors and residents in neurosurgery training programs.

OBJECTIVE: The new Accreditation Council for Graduate Medical Education (ACGME) requirements regarding resident work hours have been implemented since July 2003. Neurological surgery training programs have been especially affected because of the limited number of residency positions and the residents' long duty hours. The perceptions of program directors and residents may provide important insight into the evolution of new guidelines for improvement of resident training. METHODS: We conducted a nationwide survey of 93 program directors and 617 residents to characterize their perceptions regarding the changes in their training programs related to compliance with the ACGME requirements. The survey was conducted from July through September 2003 using electronic mail. RESULTS: The response rates were 45% and 23% among the program directors and residents, respectively. Most programs offered one (37%) or two (38%) resident training positions per year. Although 92% of programs had implemented the ACGME work hours requirements before or since July 2003, 8% had not yet implemented these guidelines. Sixty-eight percent of program directors indicated employment of ancillary health care professionals to fulfill the ACGME duty hours reform; 84% (95% confidence interval [CI], 64-94%) thought that this practice has not limited the residents' clinical experience. Eleven percent of respondents (18 of 164 respondents) who provided Level I trauma coverage were unable to maintain compliance with the ACGME guidelines. Ninety-three percent (95% CI, 89-96%) of all respondents thought that the work hour reform has had a negative impact on the continuity of patient care. Fifty-five percent (95% CI, 46-63%) of the residents and only 33% (95% CI, 20-50%) of the program directors thought that the ACGME requirements are likely to result in improved American Board of Neurological Surgery written test scores. Twenty-nine percent (95% CI, 22-37%) of the residents and 17% (95% CI, 8-32%) of the program directors thought that resident attendance at national conferences would increase. Similarly, although 46% (95% CI, 37-54%) of residents perceived that these work hour limitations would facilitate residents' research/publication-related activities, only 21% (95% CI, 11-37%) of program directors agreed. Forty-one percent (95% CI, 33-49%) of the residents and 74% (95% CI, 58-86%) of the program directors perceived that the chief residents operate on fewer complex cases since the institution of the ACGME duty hour guidelines. Seventy-five percent of residents think they are less familiar with their patients. Overall, 61% (95% CI, 53-69%) of the residents and 79% (95% CI, 63-89%) of the program directors noted that the ACGME guidelines have had a negative effect on their training programs. CONCLUSION: On the basis of their early experience, the majority of the residents and program directors think that the ACGME duty hour guidelines have had an adverse effect on continuity of patient care and resident training. The effects of these guidelines on neurosurgery programs should be carefully monitored, because more sophisticated solutions may be needed to address house staff fatigue. Strategies to enhance the educational content of the residents' work hours and to preserve continuity of patient care are necessary.

Data Collection↗
PubMed2005

Survival of cardiac arrest after aneurysmal subarachnoid hemorrhage.

OBJECTIVE: Survival of cardiac arrest (CA) after aneurysmal subarachnoid hemorrhage (SAH) is poorly characterized. We analyzed the clinical course and outcome of patients who survived resuscitation for CA after aneurysmal SAH. METHODS: Medical records of all patients with acute SAH treated at Mayo Clinic between 1990 and 1997 were reviewed. Three hundred five consecutive patients with angiographically proven aneurysmal SAH presenting within 7 days of ictus were analyzed. CA was defined as a pulseless state, documented by medical personnel, for which resuscitation was performed. Outcome was measured with the Glasgow Outcome Scale score at longest follow-up (mean, 16 mo). RESULTS: Data from 11 patients (3.6%) who had 14 episodes of CA were analyzed. Six patients had CA before reaching the hospital and were successfully resuscitated. Nine of 14 CA episodes occurred at hemorrhage or rehemorrhage. No patient with in-hospital CA failed to be resuscitated. Overall mortality in patients who had CA (46%) was higher than that of patients without CA (15%; P = 0.019). Outcome for all patients who had CA (mean Glasgow Outcome Scale score, 2.5) was worse than for patients without CA (mean Glasgow Outcome Scale score, 3.9; P = 0.005). However, half of the survivors of CA after SAH were living independently with limited deficit at longest follow-up. CONCLUSION: Most cases of CA occur at the time of initial or recurrent SAH. Resuscitation for in-hospital CA is likely to be successful. Although CA after aneurysmal SAH is associated with significantly higher mortality, the outcome of survivors of CA is not worse than that for other patients after aneurysmal SAH.

Adult↗
PubMed2005

Subarachnoid hemorrhage: neurointensive care and aneurysm repair.

Aneurysmal subarachnoid hemorrhage (SAH) is often a neurologic catastrophe. Diagnosing SAH can be challenging, and treatment is complex, sophisticated, multidisciplinary, and rarely routine. This review emphasizes treatment in the intensive care unit, surgical and endovascular therapeutic options, and the current state of treatment of major complications such as cerebral vasospasm, acute hydrocephalus, and rebleeding. Outcome assessment in survivors of SAH and controversies in screening of family members are discussed.

Angioplasty↗
PubMed2004

Extracranial thrombotically active carotid plaque as a risk factor for ischemic stroke.

CONTEXT: Recent studies suggest that factors other than the degree of carotid stenosis are involved in ischemic stroke pathogenesis, especially modifications of plaque composition and related complications. OBJECTIVE: To examine the role of carotid plaque rupture and thrombosis in ischemic stroke pathogenesis in patients undergoing carotid endarterectomy, excluding those with possible cardiac embolization or with severe stenosis of the circle of Willis. DESIGN, SETTING, AND PATIENTS: A total of 269 carotid plaques selected from an Interinstitutional Carotid Tissue Bank were studied by histology after surgical endarterectomy between January 1995 and December 2002. A total of 96 plaques were from patients with ipsilateral major stroke, 91 plaques from patients with transient ischemic attack (TIA), and 82 plaques from patients without symptoms. MAIN OUTCOME MEASURES: Differences in the frequency of thrombosis, cap rupture, cap erosion, inflammatory infiltrate, and major cardiovascular risk factors between study groups. RESULTS: A thrombotically active carotid plaque associated with high inflammatory infiltrate was observed in 71 (74.0%) of 96 patients with ipsilateral major stroke (and in all 32 plaques from patients operated within 2 months of symptom onset) compared with 32 (35.2%) of 91 patients with TIA (P < .001) or 12 (14.6%) of 82 patients who were without symptoms (P < .001). In addition, a fresh thrombus was observed in 53.8% of patients with stroke operated 13 to 24 months after the cerebrovascular event. An acute thrombus was associated with cap rupture in 64 (90.1%) of 71 thrombosed plaques from patients with stroke and with cap erosion in the remaining 7 cases (9.9%). Ruptured plaques of patients affected by stroke were characterized by the presence of a more severe inflammatory infiltrate, constituted by monocytes, macrophages, and T lymphocyte cells compared with that observed in the TIA and asymptomatic groups (P = .001). There was no significant difference between groups in major cardiovascular risk factors. CONCLUSION: These results demonstrate a major role of carotid thrombosis and inflammation in ischemic stroke in patients affected by carotid atherosclerotic disease.

Aged↗
PubMed2004

A pilot study of dendroaspis natriuretic peptide in aneurysmal subarachnoid hemorrhage.

OBJECTIVE: Hypovolemia after aneurysmal subarachnoid hemorrhage (SAH) may be mediated by natriuretic peptides and can further impair cerebral perfusion in dysautoregulated and vasospastic arterial territories. Dendroaspis natriuretic peptide (DNP), derived from the venom of Dendroaspis augusticeps, the Green Mamba snake, has recently been discovered in human plasma and atrial myocardium. There is no information regarding the presence or putative role of this peptide in patients with aneurysmal SAH. METHODS: A sensitive and specific DNP radioimmunoassay was performed on venous blood samples obtained on post-SAH Days 1, 3, and 7 from 10 consecutive SAH patients (cases) and randomly from 9 healthy volunteers (controls). Clinical and laboratory data, including daily serum sodium concentration and fluid balance, were collected prospectively up to 7 days after the ictus. RESULTS: Increase in plasma DNP levels occurred in five (63%) of eight patients who had DNP levels measured on Days 1 and 3 (mean increase, 29%). An increase in DNP level was significantly associated with development of a negative fluid balance (P = 0.003) and hyponatremia (P = 0.008). Three (75%) of the four patients who developed cerebral vasospasm during this study experienced an increase in DNP levels from Days 1 to 3. CONCLUSION: The present study is the first to find a significant association between elevated levels of DNP, a new member of the natriuretic peptide family, and the development of diuresis and natriuresis in patients with aneurysmal SAH. Our findings warrant further investigation by means of a large-scale, prospective, case-control study.

Adult↗
PubMed2004

Serum magnesium levels as related to symptomatic vasospasm and outcome following aneurysmal subarachnoid hemorrhage.

INTRODUCTION: Recent evidence suggests that magnesium may be neuroprotective in the setting of cerebral ischemia, and therapeutic magnesium infusion has been proposed for prophylaxis and treatment of delayed ischemic neurological deficit (DIND) resulting from vasospasm in patients with aneurysmal subarachnoid hemorrhage (SAH). We studied the association between serum magnesium levels, the development of DIND, and the outcomes of patients with SAH. METHODS: We studied 128 consecutive patients with aneurysmal SAH treated at our institution between 1990 and 1997 who had a serum magnesium level measured at least once during the acute phase of their hospitalization. Delayed ischemic neurological deficit was defined as severe (major focal deficit or coma), moderate (incomplete focal deficit or decreased sensorium without coma), or none. RESULTS: There was no significant difference in mean, minimum, or maximum serum magnesium levels between patients with and without DIND (1.93, 1.83, 2.02 versus 1.91, 1.84, 1.97 mg/dL, respectively). Similarly, no difference was found in mean serum magnesium levels among patients with severe (1.94 mg/dL), moderate (1.92 mg/dL), or no DIND (1.91 mg/dL). Analyses of serum magnesium levels before (0-4 days following SAH), during (4-14 days following SAH), and after (greater than 14 days following SAH) the period of highest risk for vasospasm revealed no association with the development or severity of DIND. Permanent deficit or death resulting from vasospasm and Glasgow Outcome Scale score at longest follow-up were similarly unaffected by serum magnesium levels overall or during any time interval. Forty (31.5%) patients were hypomagnesemic (less than 1.7 mg/dL) during hospitalization, but no difference in outcome (p = 0.185) or development of DIND (p = 0.785) was found when compared to patients with normal (1.7-2.1 mg/dL) or high (greater than 2.1 mg/dL) magnesium serum levels. CONCLUSION: We identified no relationship between serum magnesium levels and the development of DIND or outcome following aneurysmal SAH. Based on these data, magnesium supplementation to normal or high-normal physiological ranges seems unlikely to be beneficial for DIND resulting from vasospasm. However, no inference can be made regarding the value of therapeutic infusion of magnesium to supraphysiological levels.

Adult↗
PubMed2004

Cost of treating high-risk symptomatic carotid artery stenosis: stent insertion and angioplasty compared with endarterectomy.

OBJECT: Definitive data characterizing the safety and efficacy of carotid angioplasty with stent placement (CAS) for symptomatic, occlusive carotid artery (CA) disease require further refinements and standardization of techniques as well as large prospective studies on a par with the North American Symptomatic Carotid Endarterectomy Trial (NASCET). Despite the absence of such data, many surgeons have performed angioplasty and stent placement in patients with clinical or anatomical features known to add significant perioperative risk and capable of disqualifying the patients from participation in NASCET: There exists no cost analysis comparing high-risk endarterectomy with percutaneous angioplasty and stent insertion. METHODS: Forty-five patients (29 men and 16 women) with high-risk, symptomatic CA stenosis have been treated with CAS at the authors' institution since 1996. Indications for this procedure included symptomatic recurrent stenosis following CA endarterectomy (CEA), active coronary disease, high CA bifurcation, and severe medical comorbidities. A longstanding CEA computer database was screened for control patients with similar risk factors; 391 patients (276 men and 115 women) were identified. Actual cost data, duration of hospital stay, and relevant clinical data from the time of treatment until hospital discharge were collected in each patient. The median total cost of CAS was dollar 10,628, whereas that for CEA was dollar 10,148 (p = 0.495). CONCLUSIONS: In patients with high-risk, NASCET-ineligible CA stenosis there was no overall statistically significant cost difference between CEA and CAS. Given that there may not be a cost advantage for either procedure, procedural risk, efficacy, and durability should be key factors in determining the optimal treatment strategy.

Aged↗
PubMed2004

Influence of aspirin on outcome following aneurysmal subarachnoid hemorrhage.

OBJECT: Previous studies have indicated an increased incidence of death in patients with subarachnoid hemorrhage (SAH) who are currently receiving anticoagulation therapy. The significance of previous aspirin use in patients with SAH is unknown. The authors analyzed the effects of prior aspirin use on clinical course and outcomes following aneurysmal SAH. METHODS: The medical records of 305 patients with angiogram-confirmed aneurysmal SAH who consecutively presented to our institution between 1990 and 1997 within 7 days of ictus were analyzed. Twenty-nine (9.5%) of these patients had a history of regular aspirin use before onset of the SAH. The Glasgow Outcome Scale (GOS) was used to measure patient outcome at the longest available follow up. Aspirin users were older on average than nonusers (59 years of age compared with 53 years; p = 0.018). The mean admission Hunt and Hess grades of patients with and without aspirin use were similar (2 compared with 2.3; p = 0.51). Two trends, which did not reach statistical significance, were observed. 1) The rebleeding rate in aspirin users was 14.3%, compared with a 4.7% rebleeding rate in nonusers (p = 0.06). 2) Permanent disability from vasospasm was less common among aspirin users (23% compared with 50%; p = 0.069). Outcomes did not differ between aspirin users and nonusers (mean GOS Score 3.83 compared with GOS Score 3.86, respectively; p = 0.82). CONCLUSIONS: Despite trends indicating increased rebleeding rates and a lower incidence of permanent disability due to delayed ischemic neurological deficits, there was no significant effect of previous aspirin use on overall outcome following aneurysmal SAH. Based on these preliminary data, the presence of an intracranial aneurysm is not a strict contraindication to aspirin use.

Adult↗
PubMed2004

Pathogenesis, natural history, and treatment of unruptured intracranial aneurysms.

Unruptured intracranial aneurysms (UIAs) are a major public health issue. These lesions have become increasingly recognized in recent years with the advent of advanced cerebral imaging techniques. Epidemiological evidence from multiple sources suggests that most intracranial aneurysms do not rupture. Therefore, it is desirable to identify which UIAs are at greatest risk of rupture when considering which to repair. It is important to compare size-, site-, and group-specific natural history rates with size-, site-, and age-specific morbidity and mortality associated with UIA repair because increased natural history risk often is associated with increased risk of aneurysm repair. Patient age is crucial in decision making because of its major effect on operative morbidity and mortality; however, it does not substantially affect natural history. The effect of age is most notable in patients about 50 years of age and older for open surgery and about 70 years of age and older for endovascular procedures. In general, rupture risk is lowest for patients in asymptomatic group 1 (no history of subarachnoid hemorrhage) with UIAs less than 7 mm in diameter in the anterior circulation. Surgical morbidity and mortality are most favorable for asymptomatic patients younger than 50 years who have UIAs less than 24 mm in diameter in the anterior circulation and no history of ischemic cerebrovascular disease. Endovascular morbidity and mortality may be less age dependent, and this could favor endovascular procedures, particularly in patients aged 50 to 70 years. An important issue is determining immediate vs long-term risk regarding treatment effectiveness and durability. This issue emphasizes the importance of long-term follow-up in patients after surgical and endovascular procedures.

Adult↗
PubMed2004

Evaluation and management of transient ischemic attack and minor cerebral infarction.

After immediate intervention for cerebral infarction or transient ischemic attack (TIA), the primary goal is secondary prevention of future cerebral ischemia and prevention of complications related to the initial ischemic event. The goals of the diagnostic evaluation are to (1) determine potential contributing mechanisms (cardioembolic, large-vessel disease of the extracranial and intracranial vessels, small-vessel disease, coagulation defects, and cryptogenic), (2) identify contributing risk factors (hypertension, hyperlipidemia, tobacco use, diabetes), and (3) complete the evaluation in a cost-effective and safe manner. We provide a sequential approach to the diagnostic evaluation of cerebral infarction or TIA to optimize diagnostic yield of testing, minimize cost and potential harm to the patient, and provide information that will change management. This systematic approach focuses on 6 important questions: (1) Are the symptoms consistent with a cerebral infarction or TIA (versus nonischemic pathology)? (2) Where does the ischemic event localize? (3) What etiologies and mechanisms of cerebral infarction and TIA are possible? (4) What is the prevalence of each potential etiology? (5) What treatments are available for this etiology? (6) What tests and studies are useful to evaluate this etiology?

Adult↗
PubMed2003

Current neurosurgical indications for saphenous vein graft bypass.

OBJECT: Vascular bypass is performed in neurosurgery for a variety of pathological entities, including extracranial atherosclerotic disease, extra- and intracranial aneurysms, and tumors involving the carotid artery (CA) at the skull base or cervical regions. Creation of an interposition saphenous vein graft (SVG) is the typical method of choice when the superficial temporal artery is not an option. METHODS: One hundred thirty consecutive patients treated with SVG between July 1988 and December 2002 at the Mayo Clinic were studied. A total of 130 procedures were performed in 130 patients. The indications were intracranial aneurysm in 51 patients (39%), CA occlusive disease in 36 (28%), extracranial CA aneurysm in 17 (13%), tumors involving the cervical CA in 11 (8%), vertebral artery occlusive disease in eight (6%), and other indications in six patients (5%). Among patients treated for intracranial aneurysms, 43 harbored giant aneurysms (> 25 mm in widest diameter) whereas the remaining eight patients harbored aneurysms that were large (15-25 mm in widest diameter). Among patients with CA occlusive disease, high-grade stenosis at the CA bifurcation was present in 29 and CA occlusion was demonstrated in seven. CONCLUSIONS: The use of SVG bypass remains a valuable component of the neurosurgical armamentarium for a variety of pathological entities. Despite a general trend toward decreased use because of improved endovascular technology, surgical facility with this procedure should be maintained.

Aneurysm↗
PubMed2003

Development of a pontine cyst after endovascular coil occlusion of a basilar artery trunk aneurysm: case report.

OBJECTIVE AND IMPORTANCE: Cyst formation within the brain parenchyma after endovascular coil occlusion of an intracranial aneurysm is a previously undescribed occurrence. We describe a 70-year-old woman who presented with a symptomatic pontine cyst 1 year after uncomplicated stenting and Guglielmi detachable coil occlusion of an unruptured basilar artery trunk aneurysm. CLINICAL PRESENTATION: A 70-year-old woman presented with an episode of transient dysequilibrium and gait difficulty. Magnetic resonance imaging and cerebral angiography demonstrated a 15-mm distal basilar artery trunk aneurysm. Endovascular stenting and coil occlusion of the aneurysm were performed without technical complications. One year after the initial treatment, the patient developed progressive dysarthria, dysphagia, diplopia, and left hemiparesis. A large pontomesencephalic cyst adjacent to the coiled basilar aneurysm was identified on magnetic resonance imaging scans. INTERVENTION: A subtemporal craniotomy and decompression of the pontomesencephalic cyst were performed. The patient's symptoms of brainstem dysfunction improved temporarily but recurred within 2 months, necessitating reoperation for cyst drainage and placement of a cyst-peritoneal shunt. CONCLUSION: Intra-axial cyst formation after stenting and endovascular occlusion of an intracranial aneurysm is an unusual occurrence and should be considered in the differential diagnosis of new neurological deficits after endovascular treatment. The pathophysiological mechanism of cyst formation in this case is not known.

Aged↗
PubMed2003

Symptomatic vasospasm and outcomes following aneurysmal subarachnoid hemorrhage: a comparison between surgical repair and endovascular coil occlusion.

OBJECT: The authors studied patients with aneurysmal subarachnoid hemorrhage (SAH) to determine whether the incidence of symptomatic vasospasm or overall clinical outcomes differed between patients treated with craniotomy and clip application and those treated by endovascular coil occlusion. METHODS: The authors reviewed 415 consecutive patients with aneurysmal SAH who had been treated with either craniotomy and clip application or endovascular coil occlusion at a single institution between 1990 and 2000. Three hundred thirty-nine patients underwent surgical clip application procedures, whereas 76 patients underwent endovascular coil occlusion. Symptomatic vasospasm occurred in 39% of patients treated with clip application, 30% of patients treated with endovascular coil occlusion, and 37% of patients overall. Compared with patients treated with clip application, patients treated with endovascular coil occlusion were more likely to suffer acute hydrocephalus (50 compared with 34%, p = 0.008) and were more likely to harbor aneurysms in the posterior circulation (53 compared with 20%, p < 0.001). Logistic regression models controlling for patient age, admission World Federation of Neurosurgical Societies (WFNS) grade, acute hydrocephalus, aneurysm location, and day of treatment revealed that, among patients with an admission WFNS grade of I to III, endovascular coil occlusion carried a lower risk of symptomatic vasospasm (odds ratio [OR] 0.34, 95% confidence interval [CI] 0.14-0.8) and death or permanent neurological deficit due to vasospasm (OR 0.28, 95% CI 0.08-1) compared with craniotomy and clip application. Similar models revealed no difference in the likelihood of a Glasgow Outcome Scale score of 3 or less at the longest follow-up review (median 6 months) between treatment groups (OR 0.58, 95% CI 0.28-1.21). CONCLUSIONS: Patients with better clinical grades (WFNS Grades I-III) at hospital admission were less likely to suffer symptomatic vasospasm when treated by endovascular coil occlusion, compared with craniotomy and clip application. Nevertheless, there was no significant difference in overall outcome at the longest follow-up examination between the two treatment groups.

Adolescent↗
PubMed2003

Hemangiopericytoma of the confluence of sinuses and the transverse sinuses. Case report.

The authors describe the case of a 38-year-old man with progressive headache and blurred vision related to a hemangiopericytoma located exclusively in the confluence of sinuses (CoS) and in the transverse sinuses bilaterally. They believe this is the first report in which a hemangiopericytoma of the dural sinuses has been described without any intradural component. Although the diagnosis was not suspected preoperatively, a gross-total resection of the tumor with restoration of sinus patency was achieved to relieve the symptoms. This diagnosis should be included in the preoperative differential diagnosis of a tumor of the CoS. Successful resection can be achieved in these cases.

Adult↗