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Biomedical subjects

D G Piepgras

Publications and source records attributed to D G Piepgras.

At least 37 records · Page 2Linked to original sources
PubMed2000

Perspectives on training standards in neuroendovascular therapeutics.

Endovascular surgical neuroradiology has become a discipline in its own right, supported by a substantial and growing body of knowledge. In recognition of its emergence as a new field of study and practice, representatives from the two most influential founding disciplines, neurosurgery and neuroradiology, have defined a set of training standards, which ensure that practitioners learn both the procedures and their theoretical foundations.

Education, Medical, Graduate↗
PubMed1999

Absent pachymeningeal gadolinium enhancement on cranial MRI despite symptomatic CSF leak.

CSF leak is recognized to cause orthostatic headaches and diffuse pachymeningeal gadolinium enhancement (DPMGE) on MRI. We report six patients with typical symptoms and documented CSF leaks without DPMGE. Two had normal meninges from the onset; one initially had normal meninges, but subsequently DPMGE developed. In three, the initially noted DPMGE resolved while they were still symptomatic with documented continued CSF leaks. Absent DPMGE does not rule out CSF leak. When clinical manifestations suggest this disorder, additional diagnostic studies should be pursued.

Adolescent↗
PubMed1999

Acute deterioration from thrombosis and rerupture of a giant intracranial aneurysm.

The authors describe a patient with an unusual clinicopathologic picture of giant aneurysmal hemorrhage followed by sudden deterioration due to acute intra-aneurysmal thrombosis and fatal rebleeding. This patient underscores the poor natural history associated with this devastating disease and serves to highlight the dangers inherent in the delayed treatment of these life-threatening lesions.

Female↗
PubMed1998

Management of recurrent meningeal hemangiopericytoma.

BACKGROUND: Meningeal hemangiopericytoma is an uncommon neoplasm with a high propensity for recurrence. The purpose of this study was to analyze the efficacy of different treatment options in patients with recurrent disease. METHODS: The records of all patients with recurrent meningeal hemangiopericytoma treated at the study institution between 1976 and 1996 were reviewed. RESULTS: Thirty-four consecutive patients were studied. The mainstay of treatment was brain surgery in 21 patients (62%); the median time to recurrence from surgery was 12 months. Ten patients (29%) had 20 recurrent central nervous system (CNS) lesions treated by stereotactic radiosurgery. Of these, 3 previously nonirradiated patients (all with lesion size < 25 mm) achieved a complete response, which persisted at a median of 3 years. In 14 lesions (70%) a partial response (PR) occurred with a median duration of 12 months, whereas 3 lesions (15%) remained stable. Two patients with inoperable CNS lesions received external beam radiation therapy and both had PRs lasting 14 and 24 months, respectively. Nine patients (26%) received radiation therapy for metastatic disease. Of these, seven patients remained stable with good symptomatic relief, and two patients experienced tumor progression. Chemotherapy with doxorubicin-containing regimens was administered in 7 patients (21%); there was only 1 PR that lasted 8 months. The median survival from first recurrence was 4.6 years. CONCLUSIONS: Surgical management is important for the successful treatment of patients with recurrent meningeal hemangiopericytoma. Radiosurgery plays a definite role in the treatment of smaller recurrent CNS lesions. Radiation therapy is helpful in the management of inoperable tumors. More effective chemotherapeutic agents are needed.

Adult↗
PubMed1998

Orthostatic headaches caused by CSF leak but with normal CSF pressures.

OBJECTIVE: To report that the syndrome of orthostatic headaches caused by CSF leak can be seen with persistently normal CSF pressures. BACKGROUND: CSF leak or shunt overdrainage is known to cause orthostatic headaches and diffuse pachymeningeal gadolinium enhancement (DPGE), typically associated with unmeasurable or very low CSF pressures. METHODS: Of 40 consecutive patients with orthostatic headaches and DPGE, all had low or unmeasurable CSF pressures, except seven patients who had consistently normal CSF pressures and are thus reported. All had undergone multiple CSF examinations. RESULTS: Two patients had overdraining shunts, and five had documented CSF leaks. One refused treatment, but the other six patients responded to surgical treatment or epidural blood patch with complete resolution of symptoms and related MRI abnormalities. CONCLUSIONS: Some patients with symptomatic CSF leaks may have CSF opening pressures that are consistently within normal limits. In the presence of convincing clinical features and imaging abnormalities, a normal CSF pressure should not discourage the clinician from searching for a source of CSF leak.

Adult↗
PubMed1998

Acquired Chiari I malformation secondary to spontaneous spinal cerebrospinal fluid leakage and chronic intracranial hypotension syndrome in seven cases.

OBJECT: Spontaneous spinal cerebrospinal fluid (CSF) leakage with development of the intracranial hypotension syndrome and acquired Chiari I malformation due to lumbar spinal CSF diversion procedures have both been well described. However, concomitant presentation of both syndromes has rarely been reported. The object of this paper is to present data in seven cases in which both syndromes were present. Three illustrative cases are reported in detail. METHODS: The authors describe seven symptomatic cases of spontaneous spinal CSF leakage with chronic intracranial hypotension syndrome in which magnetic resonance (MR) images depicted dural enhancement, brain sagging, loss of CSF cisterns, and acquired Chiari I malformation. CONCLUSIONS: This subtype of intracranial hypotension syndrome probably results from chronic spinal drainage of CSF or high-flow CSF shunting and subsequent loss of brain buoyancy that results in brain settling and herniation of hindbrain structures through the foramen magnum. Of 35 cases of spontaneous spinal CSF leakage identified in the authors' practice over the last decade, MR imaging evidence of acquired Chiari I malformation has been shown in seven. Not to be confused with idiopathic Chiari I malformation, ideal therapy requires recognition of the syndrome and treatment directed to the site of the spinal CSF leak.

Adult↗
PubMed1998

Surgical treatment of spontaneous spinal cerebrospinal fluid leaks.

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.

Adult↗
PubMed1998

Ruptured giant intracranial aneurysms. Part I. A study of rebleeding.

OBJECT: The present study was conducted to estimate the frequency and timing of rebleeding after initial subarachnoid hemorrhage (SAH) from ruptured giant aneurysms. METHODS: The authors reviewed records of 109 patients who suffered an initial SAH from a giant aneurysm and were treated at the Mayo Clinic between 1973 and 1996. They represented 25% of patients with giant intracranial aneurysms seen at this institution during that 23-year period. Seven of the patients were residents of Rochester, Minnesota, and the rest were referred from other institutions. The aneurysms ranged from 25 to 60 mm in diameter, and 74% were located on arteries of the anterior intracranial circulation. The cumulative frequency of rebleeding at 14 days after admission was 18.4%. Cerebrospinal fluid drainage, cerebral angiography, and delayed aneurysm recurrence were implicated in rebleeding in some of the patients. Rebleeding was not precluded by intraaneurysm thrombosis. Among those who suffered recurrent SAH at the Mayo Clinic, 33% died in the hospital. CONCLUSIONS: Rebleeding from giant aneurysms occurs at a rate comparable to that associated with smaller aneurysms, a finding that should be considered in management strategies.

Adolescent↗
PubMed1998

Ruptured giant intracranial aneurysms. Part II. A retrospective analysis of timing and outcome of surgical treatment.

OBJECT: This retrospective study was made to determine the relationship between surgical timing and outcome in all patients with ruptured giant intracranial aneurysms undergoing surgical treatment at the Mayo Clinic between 1973 and 1996. METHODS: The authors studied 109 patients, 102 of whom were referred from other medical centers. The ruptured giant aneurysms were 25 to 60 mm in diameter. One hundred five of the patients survived the rupturing of the aneurysm to undergo operation, with direct surgery possible in 84% of cases. Excluding delayed referrals, the average time to surgery after admission to the Mayo Clinic was approximately 4 to 5 days. Patients admitted earlier tended to be in poorer condition, often undergoing earlier operation. On average, surgical treatment was administered later for patients with ruptured aneurysms of the posterior circulation than for those with aneurysms in the anterior circulation. Temporary occlusion of the parent vessel was necessary in 67% of direct procedures, with an average occlusion time of 15.5 minutes. Among surgically treated patients, a favorable outcome was achieved in 72% harboring ruptured anterior circulation aneurysms and in 78% with ruptured posterior circulation lesions. CONCLUSIONS: The overall management mortality rate was 21.1%, and the mortality rate for surgical management was 8.6%. The authors believe that because of the technical difficulties and risk of rebleeding associated with ruptured giant intracranial aneurysms, timely referral to and well-planned treatment at medical centers specializing in management of these lesions are essential to effect a more favorable outcome.

Age Factors↗
PubMed1997

Intracranial aneurysms in Marfan's syndrome: an autopsy study.

OBJECTIVE: Marfan's syndrome is a heritable connective tissue disorder that has been associated with intracranial aneurysms. However, the prevalence of intracranial aneurysms in Marfan's syndrome is unknown and pathological studies of affected vessels have not been reported. We therefore examined the neuropathological findings in a group of patients with Marfan's syndrome. METHODS: We identified all patients with Marfan's syndrome in whom postmortem examination had been performed at the Mayo Clinic between 1969 and 1993. RESULTS: Autopsy included examination of the brain in seven patients with Marfan's syndrome (five men and two women with a mean age of 28 yr). Each of two patients had one or more intracranial aneurysms. The first patient, a 32-year-old man who died as a result of aortic dissection, was observed to have an incidental saccular supraclinoid carotid artery aneurysm (7 mm). Microscopic examination of the remainder of the cerebral arteries revealed duplication and fragmentation of the internal elastic lamina. The second patient, a 20-year-old man who died as a result of a subarachnoid hemorrhage, had ruptured saccular supraclinoid carotid artery (3 mm) and anterior cerebral artery (20 mm) aneurysms as well as unruptured fusiform middle cerebral artery (18 mm) and posterior cerebral artery (13 mm) aneurysms. Microscopic examination of the cerebral arteries revealed widespread changes consisting of intimal proliferation, medial degeneration, and fragmentation of the internal elastic lamina. CONCLUSION: These findings confirm an association between Marfan's syndrome and intracranial aneurysms. Microscopic involvement of cerebral arteries in Marfan's syndrome may be variable, even among those with intracranial aneurysms.

Adult↗
PubMed1997

Familial intracranial aneurysms: an autopsy study.

OBJECTIVE: Familial intracranial aneurysms are more common than has been appreciated, but systematic autopsy studies of affected individuals have not been reported. We reviewed the autopsy findings of a group of patients with familial aneurysms to elucidate the nature of the putative underlying arteriopathy. METHODS: Using a computerized diagnostic index, we identified all patients with intracranial aneurysms in whom postmortem examination had been performed at the Mayo Clinic between January 1, 1992, and December 31, 1994. The medical records, radiographic studies, and autopsy findings of these patients were reviewed. RESULTS: Among the 28 patients with intracranial aneurysms, 3 (11%) had one or more first-degree relatives with documented intracranial aneurysms. The mean age of the three patients (two women and one man) was 54 years. Microscopic examination of the vascular system revealed medial changes, consisting of degeneration of elastic fibers and increased ground substance, in the systemic arteries of 2 of the 3 patients with familial aneurysms but in none of the 25 patients with sporadic aneurysms. These nonspecific medial changes involved both common and extracranial internal carotid arteries in one patient and the entire aorta as well as intracranial and common carotid arteries in the other patient. CONCLUSION: These observations suggest that an underlying arteriopathy in patients with familial intracranial aneurysms involves the tunica media and commonly may affect systemic (extracranial) arteries.

Adult↗
PubMed1997

Endovascular treatment of cerebral aneurysms following incomplete clipping.

The authors report their experience using electrolytically detachable coils for the treatment of residual cerebral aneurysms following incomplete surgical clipping. Eight patients were treated for six anterior and two posterior circulation aneurysm remnants. All patients were referred for endovascular treatment by experienced cerebrovascular neurosurgeons at the authors' institution. Patients underwent follow-up angiography immediately after endovascular treatment. In seven of the eight patients, additional follow-up angiographic studies were obtained at periods ranging from 7 weeks to 2 years posttreatment. The latest follow-up angiograms demonstrated that six of the eight aneurysm remnants were 100% occluded, with near-complete occlusion of the other two aneurysm remnants. There was no permanent neurological or non-neurological morbidity or mortality associated with the treatment. There was no incidence of aneurysm hemorrhage during or after treatment. Endovascular treatment of cerebral aneurysm remnants following prior surgical clipping can be accomplished with acceptable morbidity and mortality rates. Endovascular coil occlusion can play an important adjunctive role in the treatment of those aneurysms that have been incompletely obliterated by surgical clipping.

Adult↗
PubMed1997

Endovascular treatment of ruptured posterior circulation aneurysms using electrolytically detachable coils.

The authors report their experience using electrolytically detachable coils for the treatment of ruptured posterior circulation aneurysms. Twenty-six patients with 28 posterior circulation aneurysms were treated. All patients were referred for endovascular treatment by experienced vascular neurosurgeons. Patients underwent follow-up angiography immediately after treatment, 1 to 6 weeks posttreatment, and 6 months posttreatment. Six-month follow-up angiograms obtained in 19 patients with 20 aneurysms demonstrated that 18 (90%) of the 20 aneurysms were 99 to 100% occluded, one aneurysm (5%) was approximately 90% occluded, and one aneurysm (5%) was approximately 75% occluded. The patient with the aneurysm that was approximately 75% occluded needed additional treatment, consisting of parent artery balloon occlusion, and was considered a treatment failure (3.8% of patients). There was one treatment-associated mortality (3.8%) but no treatment-associated serious neurological or nonneurological morbidity in the patient group. There was no recurrent aneurysm rupture during treatment or during the mean 27-month follow-up period. Endovascular treatment of ruptured posterior circulation aneurysms with electrolytically detachable coils can be accomplished with low morbidity and mortality rates. The primary goal of treatment--preventing recurrent aneurysm--can be achieved over the short term. Endovascular coil occlusion will play an important role in the treatment of ruptured posterior circulation aneurysms, particularly if long-term efficacy in preventing recurrent aneurysm hemorrhage can be documented.

Adult↗
PubMed1997

Intra-arterial thrombolysis in acute basilar artery thromboembolism: the initial Mayo Clinic experience.

OBJECTIVE: To investigate the feasibility of intra-arterial thrombolysis in acute basilar artery thrombosis. DESIGN: We reviewed a consecutive series of patients in whom intra-arterial thrombolysis was performed during the period from 1994 to 1996. MATERIAL AND METHODS: Intra-arterial thrombolysis with urokinase was done in an attempt to recanalize the basilar artery in a series of nine patients with basilar artery thrombosis admitted to the neurologic intensive care unit. At the time of initial assessment, all nine patients had major neurologic deficits attributable to brain-stem ischemia, including two patients with locked-in syndrome. RESULTS: Recanalization of the basilar artery system was successful in seven of the nine patients (a range of 2 to 13 hours after the ictus). Failure to recanalize the basilar artery occurred in two patients, who died after progressing to coma. Complete recovery or only minimal neurologic deficits were demonstrated in five of the nine patients. Despite recanalization of the basilar artery, two patients had no major change in their neurologic function, and both ultimately had severe ataxia and were fully dependent on others. A cerebellar hemorrhage occurred in one patient but without clinical worsening. Two patients had a retroperitoneal hematoma. CONCLUSION: Intra-arterial thrombolysis with urokinase in acute basilar artery occlusion resulted in recanalization in seven of the nine patients (78%). Five of the nine patients recovered fully, including two patients who had had locked-in syndrome. In light of the devastating natural course of acute basilar artery occlusion, these initial results are encouraging and indicate that intra-arterial thrombolysis may be a useful emergency treatment, even in patients with prolonged symptoms of ischemia (up to 12 hours).

Adult↗
PubMed1997

Syndrome of orthostatic headaches and diffuse pachymeningeal gadolinium enhancement.

OBJECTIVE: To characterize clinical and imaging features, biopsy findings, etiologic factors, and outcome in the syndrome of intracranial hypotension, headaches, and diffuse pachymeningeal gadolinium enhancement on magnetic resonance imaging (MRI). MATERIAL AND METHODS: We describe our experience with 26 consecutive patients with orthostatic headaches and diffuse pachymeningeal gadolinium enhancement, for all of whom clinical, imaging, and follow-up data were available. For 10 patients who had undergone meningeal biopsy, slide material was also reviewed. RESULTS: The 15 men and 11 women ranged from 24 to 76 years of age. All 26 patients had postural headaches; in 22 patients, the headaches were completely alleviated by recumbency. Nausea or emesis, neck pain, horizontal diplopia, changes in hearing, photophobia, upper limb pains or paresthesias, visual blurring, or dysgeusia was noted in some of the patients. Cardinal MRI features were diffuse pachymeningeal gadolinium enhancement (100%), subdural collections of fluid (69%), and evidence of descent of the brain (62%) that sometimes resembled type I Chiari malformation. Cerebrospinal fluid (CSF) opening pressures were 40 mm or less in only 46%. In three patients, CSF pressures were consistently no less than 90 and as high as 130 mm of water. A variable pleocytosis of 5 or more cells/mm3 was noted in 15 patients (more than 40 cells/mm3 in 4 patients). A variable increase in CSF protein was noted in at least one spinal tap in 23 patients. Six patients had overdraining CSF shunts; CSF leak was documented in another 11 patients. Shunt revision or ligation and surgical correction of the leak led to a resolution of the clinical and MRI abnormalities in all cases thus treated. Improvement occurred with epidural blood patch in four patients. Three of the 12 patients treated supportively have remained symptomatic. Histologically, a thin subdural zone of fibroblasts and thin-walled vessels was noted in an amorphous matrix. Two patients with prolonged symptoms had a more pronounced proliferative reaction. CONCLUSION: The syndrome of low-pressure headaches and pachymeningeal gadolinium enhancement is being recognized with increasing frequency. The source of the CSF leak can be demonstrated in many patients. Meningeal abnormalities are likely attributable to decreased CSF volume and hydrostatic CSF pressure changes. The prognosis is typically good.

Adult↗