David G. Piepgras
Mayo Clinic
Network
Latest external collaboration on country level. Dive into details by clicking on the dots.
Publication
Featured researches published by David G. Piepgras.
Cancer | 1986
Barbara S. Ducatman; Bernd W. Scheithauer; David G. Piepgras; Herbert M. Reiman; Duane M. Ilstrup
A review was done of 120 cases of malignant peripheral nerve sheath tumor (MPNST) seen during a 71‐year period. Of the 120 patients, 52 were males and 68 were females with a mean age at diagnosis of 35.3 years; 12 patients were younger than 20 years. The series included 62 (52%) patients with neurofibromatosis, 13 (11%) with postradiation sarcomas, and 19 (16%) with metaplastic foci. The incidence of MPNST arising in neurofibromatosis was 4.6% in the current series and 0.001% in the general clinic population. Tumors> 5 cm and the presence of neurofibromatosis adversely affected the prognosis (P <0.05). When both features were present, survival was greatly decreased. Patients with tumor in the extremities did better than those with head or neck lesions. Metaplastic foci or previous radiation at the tumor site did not alter the prognosis. Each tumor was graded 1 to 4 on the basis of cellularity, pleomorphism, mitotic index, and necrosis. No significant correlation was noted between survival and either grade or mitotic rate. Survival was improved when total rather than subtotal resection was done. This was most marked in patients with a small lesion, which may reflect the difficulty in adequately excising large tumors. Adjuvant radiation or chemotherapy did not appear to affect survival. The MPNST is an aggressive uncommon neoplasm, and large tumor size, the presence of neurofibromatosis, and total resection are the most important prognostic indicators.
Circulation | 2000
Joshua B. Bederson; Issam A. Awad; David O. Wiebers; David G. Piepgras; E. Clarke Haley; Thomas G. Brott; George Hademenos; Douglas Chyatte; Robert H. Rosenwasser; Cynthia Caroselli
Aneurysmal subarachnoid hemorrhage (SAH) has a 30-day mortality rate of 45%, with approximately half the survivors sustaining irreversible brain damage.1 On the basis of an annual incidence of 6 per 100 000, ≈15 000 Americans will have an aneurysmal SAH each year. Population-based incidence rates vary considerably from 6 to 16 per 100 000, with the highest rates reported from Japan and Finland.2 3 4 5 Approximately 5% to 15% of stroke cases are secondary to ruptured saccular aneurysms. Although the prevention of hemorrhage has been advocated as the most effective strategy aimed at lowering mortality rates,6 the optimal management of patients with unruptured intracranial aneurysms (UIAs) remains controversial. Management decisions require an accurate assessment of the risks of various treatment options compared with the natural history of the condition. The natural history of UIAs and treatment outcomes are influenced by (1) patient factors, such as previous aneurysmal SAH, age, and coexisting medical conditions; (2) aneurysm characteristics, such as size, location, and morphology; and (3) factors in management, such as the experience of the surgical team and the treating hospital. These many influences have contributed to considerable variability in the reported risks for aneurysmal SAH and the treatment of UIAs. There are no prospective randomized trials of treatment interventions versus conservative management to date, and it is possible that no such studies will be carried out in the future. According to a classification system suggested by Cook et al,7 randomized clinical trials with low likelihoods of false-positive and false-negative errors provide the highest level of evidence (level I) that can be applied to a clinical recommendation. Randomized trials with high likelihoods of false-negative and positive errors provide level II evidence. Level III evidence is generated with nonrandomized concurrent cohort comparisons between contemporaneous patients who did and …
Neurology | 1988
Bahram Mokri; O. W. Houser; B. A. Sandok; David G. Piepgras
Clinical and angiographic features and outcome in 25 patients with spontaneous dissections of the vertebral arteries are described. Most patients were in their fourth or fifth decade of life, and women predominated. Forty-eight percent of the patients were hypertensive. Angiographic evidence of fibromuscular dysplasia was noted in one only. Brainstem ischemic symptoms (usually a lateral medullary syndrome) and ipsilateral occipital headache and neck pain (often preceding but sometimes associated with or following the brainstem ischemic event) were the most common clinical findings. The angiographic features in decreasing order of frequency were luminal stenosis (often irregular and tapered), aneurysm, occlusion, and intimal flap. On follow-up, most of the patients (88%) made complete or very good recoveries. Angiographic abnormalities either subsided or improved in 76%. Multivessel dissection (involvement of both vertebral arteries or one or both vertebral arteries and one or both internal carotid arteries) was noted in about two-thirds of the patients. This tendency of vertebral artery dissections to involve multiple cervicocephalic vessels concurrently, if not simultaneously, implies that four-vessel angiography should be attempted if a vertebral artery dissection is visualized. It also raises the possibility of an underlying arteriopathy that predisposes the vessel to dissection.
Stroke | 1994
Wouter I. Schievink; Virginia V. Michels; David G. Piepgras
Background Heritable disorders of connective tissue are recognized in a small minority of patients with neurovascular diseases. In this report, we review the neurovascular manifestations of four heritable connective tissue disorders: Ehlers‐Danlos syndrome, Marfans syndrome, osteogenesis imperfecta, and pseudoxanthoma elasticum, as well as two other systemic disorders with potential vascular manifestations: neurofibromatosis and polycystic kidney disease. Summary of Review Typical neurovascular complications of Ehlers‐Danlos syndrome are carotid‐cavernous fistulae, intracranial aneurysms, and cervical artery dissections. Arterial dissections and intracranial aneurysms cause the majority of neurovascular symptoms in Marfans syndrome. Neurovascular disease is uncommon in osteogenesis imperfecta, although carotid‐cavernous fistulae and vertebral artery dissections have been reported. Neurovascular disease in pseudoxanthoma elasticum is characterized by intracranial aneurysms and cerebral ischemia caused by premature arterial occlusive disease. Intracranial occlusive arterial disease is the most common neurovascular manifestation of neurofibromatosis, followed by cervical arteriovenous fistulae and aneurysms and intracranial aneurysms. Intracranial aneurysms are the hallmark of polycystic kidney disease. Conclusions Recognition of an underlying generalized connective tissue disorder may be of considerable importance, although marked phenotypic heterogeneity often complicates the diagnosis of these disorders. Conversely, the association of certain neurovascular anomalies with generalized connective tissue disorders and recognition of their basic molecular defect may offer clues to the etiology and pathogenesis of these neurovascular diseases in general. (Stroke. 1994;25:889‐903.)
Neurology | 1995
Wouter I. Schievink; Eelco F. M. Wijdicks; Joseph E. Parisi; David G. Piepgras; Jack P. Whisnant
Article abstract—Some patients with aneurysmal subarachnoid hemorrhage (SAH) never reach the hospital alive (“sudden death”) and, although their numbers are significant, they are not included in most studies of SAH. To clarify the clinical profile of sudden death from aneurysmal SAH, we reviewed the epidemiology and clinicopathologic features of patients with aneurysmal SAH who never reached medical attention. Using the medical record linkage system employed for epidemiologic studies for the population of Rochester, Minnesota, we identified all patients who were diagnosed with aneurysmal SAH between 1960 and 1989. There were 80 women and 33 men with a mean age of 55 years. Of these 113 patients, 13 (12%) died without reaching medical attention. The proportion of those with sudden death remained stable during the study period. In comparing patients with sudden death with those who reached medical attention, the only significant variable was the frequency of posterior circulation aneurysms that was found in 38%, compared with 14% in those who received medical attention (p = 0.042). At autopsy, intraventricular hemorrhage was present in 12 patients (92%) with sudden death, and intracerebral hemorrhage was present in two (15%). Twelve patients (92%) had acute pulmonary edema. In our community, the frequency of sudden death from aneurysmal SAH has not changed during the last three decades in spite of the advances in medical care. The typical clinical profile of sudden death in SAH includes intraventricular hemorrhage, pulmonary edema, and a ruptured posterior circulation aneurysm. Intracerebral hemorrhage is uncommonly associated with sudden death from aneurysmal SAH.
Stroke | 2000
Joshua B. Bederson; Issam A. Awad; David O. Wiebers; David G. Piepgras; E. Clarke Haley; Thomas G. Brott; George Hademenos; Douglas Chyatte; Robert H. Rosenwasser; Cynthia Caroselli
Aneurysmal subarachnoid hemorrhage (SAH) has a 30-day mortality rate of 45%, with approximately half the survivors sustaining irreversible brain damage.1 On the basis of an annual incidence of 6 per 100 000, ≈15 000 Americans will have an aneurysmal SAH each year. Population-based incidence rates vary considerably from 6 to 16 per 100 000, with the highest rates reported from Japan and Finland.2 3 4 5 Approximately 5% to 15% of stroke cases are secondary to ruptured saccular aneurysms. Although the prevention of hemorrhage has been advocated as the most effective strategy aimed at lowering mortality rates,6 the optimal management of patients with unruptured intracranial aneurysms (UIAs) remains controversial. Management decisions require an accurate assessment of the risks of various treatment options compared with the natural history of the condition. The natural history of UIAs and treatment outcomes are influenced by (1) patient factors, such as previous aneurysmal SAH, age, and coexisting medical conditions; (2) aneurysm characteristics, such as size, location, and morphology; and (3) factors in management, such as the experience of the surgical team and the treating hospital. These many influences have contributed to considerable variability in the reported risks for aneurysmal SAH and the treatment of UIAs. There are no prospective randomized trials of treatment interventions versus conservative management to date, and it is possible that no such studies will be carried out in the future. According to a classification system suggested by Cook et al,7 randomized clinical trials with low likelihoods of false-positive and false-negative errors provide the highest level of evidence (level I) that can be applied to a clinical recommendation. Randomized trials with high likelihoods of false-negative and positive errors provide level II evidence. Level III evidence is generated with nonrandomized concurrent cohort comparisons between contemporaneous patients who did and …
Annals of Surgery | 1986
Fredric B. Meyer; Thoralf M. Sundt; David G. Piepgras; Burton A. Sandok; Forbes Gs
Emergency revascularization procedures for patients with acute stroke are controversial. Thirty-four patients with acute internal carotid artery occlusion documented at the time of emergency endarterectomy were analyzed. Before operation, all these patients had profound neurological deficits including hemiplegia and aphasia. There was a 94% success rate in restoring patency. In follow-up, nine patients (26.5%) had a normal neurological exam, four (11.8%) had a minimal deficit, 10 (29.4%) had a moderate hemiparesis, which was improved over their preoperative deficit, 4 (11.8%) remained hemiplegic, and seven (20.6%) died. The natural history of patients with acute carotid occlusion and profound neurological deficits is dismal. In comparison, 13 patients (38%) made a dramatic recovery. The surgical mortality rate compares favorably with the natural history. Good collateral flow was a good prognostic factor, while a simultaneous middle cerebral artery embolus was associated with a poorer prognosis. An emergency carotid endarterectomy may be indicated in selected patients with acute internal carotid artery occlusion with profound neurological deficits. Full preoperative angiography may identify those patients who would benefit from surgical intervention and reduce the operative mortality rate.
Journal of Neurosurgery | 1998
Wouter I. Schievink; Vittorio M. Morreale; John L. D. Atkinson; Fredric B. Meyer; David G. Piepgras; Michael J. Ebersold
OBJECT Spontaneous spinal cerebrospinal fluid (CSF) leaks are an increasingly recognized cause of intracranial hypotension and may require neurosurgical intervention. In the present report the authors review their experience with the surgical management of spontaneous spinal CSF leaks. METHODS Between 1992 and 1997, 10 patients with spontaneous spinal CSF leaks and intracranial hypotension were treated surgically. The mean age of the seven women and three men was 42.3 years (range 22-61 years). Preoperative imaging showed a single meningeal diverticulum in two patients, a complex of diverticula in one patient, and a focal CSF leak alone in seven patients. Surgical exploration in these seven patients demonstrated meningeal diverticula in one patient; no clear source of CSF leakage could be identified in the remaining six patients. Treatment consisted of ligation of the diverticula or packing of the epidural space with muscle or Gelfoam. Multiple simultaneous spinal CSF leaks were identified in three patients. CONCLUSIONS All patients experienced complete relief of their headaches postoperatively. There has been no recurrence of symptoms in any of the patients during a mean follow-up period of 19 months (range 3-58 months; 16 person-years of cumulative follow up). Complications consisted of transient intracranial hypertension in one patient and leg numbness in another patient. Although the disease is often self-limiting, surgical treatment has an important role in the management of spontaneous spinal CSF leaks. Surgery is effective in eliminating the headaches and the morbidity is generally low. Surgical exploration for a focal CSF leak, as demonstrated on radiographic studies, usually does not reveal a clear source of the leak. Some patients may have multiple simultaneous CSF leaks.
Neurology | 1996
Bahram Mokri; Peter L. Silbert; Wouter I. Schievink; David G. Piepgras
Cranial nerve palsy was present in 23 of 190 consecutive adult patients (12%) with spontaneous dissection of the extracranial internal carotid artery.Ten patients (5.2%) had a syndrome of lower cranial nerve palsies (with invariable involvement of cranial nerve XII with or without additional involvement of cranial nerves XI, X, and IX), seven (3.7%) had palsy of cranial nerve V, and five (2.6%) had a syndrome of ocular motor palsies. Palsy of cranial nerve VIII and ischemic optic neuropathy occurred in one patient each. Three patients had dysgeusia without other cranial nerve involvement, presumably due to involvement of the chorda tympani nerve. Headache or face pain (often unilateral) was present in 83% of patients. Other associated manifestations were cerebral ischemic symptoms, bruits, or oculosympathetic palsy. In one patient, cranial nerve palsy was the only manifestation of internal carotid artery dissection, and in another patient, the disease presented only as a palsy of cranial nerve XII and oculosympathetic palsy. In six patients, a syndrome of hemicrania and ipsilateral cranial nerve palsy was the sole manifestation of internal carotid artery dissection. Cranial nerve palsy is not rare in internal carotid artery dissection. Compression or stretching of the nerve by the expanded artery may explain some but not all of the palsies. An alternative mechanism is likely interruption of the nutrient vessels supplying the nerve. NEUROLOGY 1996;46: 356-359
Journal of Vascular Surgery | 1987
Martha M. Reigel; Larry H. Hollier; Thoralf M. Sundt; David G. Piepgras; Frank W. Sharbrough; Kenneth J. Cherry
Neurologic deficits evident when patients initially awaken from surgery are generally due to intraoperative embolization or inadequate cerebral protection in patients with marginal cerebral perfusion; neurologic deficits occurring in the immediate postoperative period are usually related to acute carotid occlusion or embolization. However, in a small subset of patients, transient postoperative neurologic dysfunction seems to be related to a syndrome of cerebral hyperperfusion rather than a lack of adequate cerebral blood flow. This study describes the courses of 10 patients with classic findings of cerebral hyperperfusion syndrome. Typically, this syndrome occurred in patients with longstanding severe chronic cerebral ischemia and occurred after correction of a very high-grade carotid stenosis. Intraoperatively, there was often a dramatic increase in xenon-labeled cerebral blood flows, with postocclusion flows sometimes attaining three to four times baseline levels. Postoperatively, the patients initially did well. However, over the next several days, many of them began to complain of unilateral headache on the operated side and subsequently had seizures. Electroencephalography obtained during this period uniformly revealed periodic lateralizing epileptiform discharges on the side of the brain ipsilateral to the endarterectomy. Although neurologic dysfunction fully resolved in all of the patients in this group, it is possible that intracerebral hemorrhage may occur in some patients with hyperperfusion syndrome. The pathophysiology of this syndrome is believed to be related to preoperative loss of cerebral autoregulatory mechanisms caused by chronic cerebral ischemia.