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Purpose: To review our experience using MR angiography to assess the cerebral vasculature after aneurysmal treatment with Guglielmi detachable coils (GDCs)., Methods: Forty three-dimensional time-of-flight MR angiographic studies were performed in 23 patients after endovascular aneurysmal therapy with GDCs. Digital subtraction angiographic (DSA) studies were evaluated retrospectively for the following findings: parent artery patency, branch vessel patency, residual flow within the aneurysm, and residual aneurysmal neck. The MR angiographic examinations were inspected for the same findings, as well as for the degree of signal loss surrounding the coil mass. Clinical histories were reviewed to determine the impact of MR angiographic findings on therapy., Results: Patency status of the parent artery was correctly identified on 25 of 26 MR angiographic examinations with DSA confirmation. Thirty-four of 37 patent branch vessels were identified by MR angiography. Residual neck was correctly identified in seven studies of six aneurysms, with no false-negative or false-positive results. Intraaneurysmal flow was correctly identified in five of eight studies of six aneurysms with residual flow shown by DSA. Artifact and hemorrhage mimicked residual flow in two of 18 MR angiographic studies of aneurysms with no residual flow shown by DSA. In eight patients, MR angiography provided clinically useful information that affected therapy., Conclusions: MR angiography can identify flow within an aneurysm after treatment with GDCs as well as in the adjacent parent and branch vessels. This technique may be a useful adjunct to DSA in some clinical situations.

Purpose: To determine the effect of proximal flow arrest on the frequency and timing of distal embolic events during occlusion of the common femoral artery with detachable coils., Methods: Twenty-three complex fibered platinum coils were delivered into 10 common femoral arteries without proximal flow arrest. The arteries were continuously monitored for flow and embolic events by Doppler sonography during delivery and for at least 10 minutes after delivery of each coil. Thirty-four coils were delivered into 6 arteries after proximal flow arrest by inflation of a nondetachable balloon. After balloon deflation, each artery was monitored by Doppler sonography for 10 minutes., Results: In the 10 arteries occluded without flow arrest, 87 events (8.7 per artery) occurred, of which 47 were embolic and 40 were indeterminate. In the 6 arteries with flow arrest, the number of emboli detected was 3 (0.5 per artery). Embolic events occurred only if there was residual flow. In those arteries that were occluded when the flow-arrest balloon was deflated, no emboli were detected., Conclusions: Proximal flow arrest virtually eliminates the risk of distal emboli during arterial occlusion with detachable fibered coils. The use of fibered coils, in conjunction with proximal flow arrest, allows for safe arterial occlusion when detachable balloons are not available or their use is not feasible.

Three patients with vertebrobasilar junction aneurysms and associated fenestration were treated with Guglielmi detachable coils. The structure and hemodynamics of fenestrations may account for their frequent association with aneurysms. The complex hemodynamics of these aneurysms requires evaluation of both vertebral arteries. One treatment complication occurred but resulted in no deficit. All patients have returned to normal activity and remain healthy at 14 to 46 months.

The major causes of mortality and morbidity in patients surviving the rupture of a saccular aneurysm are subsequent bleeding and vasospasm. The purpose of this study was to evaluate the influence of early treatment of ruptured aneurysms with Guglielmi detachable coils on the incidence of subsequent bleeding. Thirteen patients were treated within 72 hours of initial aneurysm rupture with Guglielmi detachable coils. Excluding three patients who died 2, 4, and 12 weeks after initial hemorrhage, all others have been followed up for intervals between 6 and 36 months (mean, 16 mo). None of these have had either clinical or radiographic evidence of subsequent bleeding. Assuming that there is a 30% incidence of subsequent bleeding in conservatively (nonsurgically) treated patients, the 0% subsequent bleed rate observed in this subgroup was significant at a P value of 0.01. Only one procedure-related complication occurred in this series, and 9 of 13 (69%) aneurysms were 100% occluded at the time of initial treatment. All aneurysms were at least 90% occluded at the end of initial treatment. In addition to reducing the risk of subsequent bleeding, early treatment facilitated the institution of an aggressive approach for management of both vasospasm and increased intracranial pressure. Patient outcome, as measured by the Glasgow Outcome Scale, was good in 9 of 13 (69%), poor in 1 of 13 (8%), and death in 3 of 13 (23%) patients. The results of this study suggest that early Guglielmi detachable coil treatment of ruptured aneurysms may be effective in reducing the incidence of subsequent bleeding and can be performed with a low incidence of complications.(ABSTRACT TRUNCATED AT 250 WORDS)

Goodpasture's syndrome rarely affects children. Therefore, we present our experience in a young boy whose pulmonary hemorrhage was dramatically resolved by three plasma exchanges. We believe the hemorrhage was caused primarily by acute capillaritis. He received cytoxan and steroids and a series of plasma exchanges which removed/suppressed his anti-glomerular basement membrane (anti-GBM) antibody production. However, after a year, his renal function did not return, and he required renal transplantation and continues to do well.

This study compares differences in the cellularity and levels of CD34 positive cells in bone marrows from patients treated with G-/GM-CSF prior to harvest and marrows from untreated patients. The average volume of marrow aspirated was 1302mL in the untreated group containing an average of 2.6 x 10(10) nucleated cells, while an average volume of 1147mL of marrow was aspirated from patients treated with GM-/G-CSF prior to harvest which contained an average of 5.6 x 10(10) nucleated cells. Analysis of these marrows by flow cytometry revealed a higher percentage of CD34 positive cells within the lymphoid gate of marrow specimens from patients receiving GM-/G-CSF as compared with their untreated counterparts (21.4% vs. 9.1%). All patients receiving GM-/G-CSF prior to harvest were also given G-CSF subcutaneously (5 micrograms/kg/day) following the infusion of autologous marrow after high dose myelosuppressive chemotherapy and the duration of neutropenia (AGC < 500/mm3) in this group was shortened, an average of 12 days as compared to 24 days in untreated patients. This decreased duration of neutropenia is similar to that reported in patients receiving GM-/G-CSF only after transplantation (Lieschke & Burgess, 1992). Further studies are needed to determine whether the administration of GM-/G-CSF prior to bone marrow harvest is clinically beneficial.

A canine model of terminal aneurysms using a venous pouch surgical technique is described. This model mimics the anatomy and hemodynamics of some types of carotid and basilar tip aneurysms. This technique produces aneurysms 15 x 21 mm in size. The aneurysms have been used to investigate the hemodynamics and treatment of terminal aneurysms.

The authors investigate a modification of the Gugliemi detachable coil. They have developed a rabbit model and coating technique to test differences in thrombogenicity of platinum coils with a variety of polyurethanes.

A microcatheter foreign body retrieval device is described and its first two clinical applications are presented. The device functions identically to larger loop snare retrievers. It permits access to small vessels and was successful in its first clinical applications.

A new retrieval device for use in small vessels was evaluated in a canine model. Retrieval was attempted on 25 coils, three silicone balloons, and five catheter and guide wire fragments placed in the renal, pulmonary, hepatic, brachiocephalic, subclavian, carotid, and maxillary arteries. This was successful in 91% (30/33). The snare could also be selectively placed in the vertebral and proximal basilar arteries.

Purpose: To evaluate and compare the deliverability, positioning, stability, and effectiveness of aneurysm occlusion and the incidence of parent-artery thrombosis of two different types of platinum coils, using a canine carotid aneurysm model., Methods: 29 experimental canine carotid aneurysms (19 lateral, 6 bifurcation, and 4 terminal) were constructed and treated with complex-shaped fibered platinum coils and simple curved nonfibered platinum Guglielmi detachable coils (GDCs)., Results: Fibered complex coils were stable, producing 38% complete aneurysm occlusion and 61% average reduction in aneurysm lumen size but resulting in 19% parent artery occlusions. GDC coils were stable, producing 31% complete aneurysm occlusion and 95% average reduction in aneurysm lumen size with no parent-artery occlusions., Conclusions: GDC coils produced an average reduction in aneurysm lumen size of 95% without any associated parent-artery occlusions. There were no delayed migrations of GDC coils. The ability to remove, reposition, and detach a coil was the most significant feature of the GDC coil.

A rare anomalous origin of the posterior inferior cerebellar artery arising from the internal carotid artery is described. The embryologic explanation postulated is the persistence of a primitive communicating vessel (presegmental artery) between the anterior and posterior circulation.

In a multicenter study, 120 patients with intracranial aneurysms presenting a high surgical risk were treated using electrolytically detachable coils and electrothrombosis via an endovascular approach. The results of treatment in patients with posterior fossa aneurysms (42 patients with 43 aneurysms) are presented. The most frequent clinical presentation was subarachnoid hemorrhage (24 cases). The clinical follow-up periods ranged from 1 week to 18 months. Complete aneurysm occlusion was obtained in 13 of 16 aneurysms with a small neck and in four of 26 wide-necked aneurysms. A 70% to 98% thrombosis of the aneurysm was achieved in 22 of 26 aneurysms with a wide neck and in three of 16 small-necked aneurysms. One aneurysm could not be treated due to a technical complication. Two cases required postprocedural surgical clipping of a residual aneurysm. One patient (originally in Hunt and Hess Grade V) experienced procedural rupture of the aneurysm requiring an emergency parent artery occlusion. He eventually died 5 days later. Another patient (originally in Grade IV) had coil migration and posterior cerebral artery territory ischemia. A third patient developed a permanent neurological deficit (hemianopsia) after complete occlusion of a wide-necked basilar bifurcation aneurysm. One patient, harboring an inoperable giant basilar bifurcation aneurysm, died from aneurysm bleeding 18 months after partial occlusion. Overall morbidity and mortality rates related to treatment were 4.8% (two cases) and 2.4% (one case), respectively (2.6% and 0% if considering only patients in Hunt and Hess Grades I, II, and III). It is suggested that this technique is a viable alternative in the management of patients with posterior fossa aneurysms associated with high surgical risk. Longer angiographic and clinical follow-up study is necessary to determine the long-term efficacy of this recently developed endovascular occlusion technique. Close postoperative angiographic and clinical monitoring of patients with wide-necked subtotally occluded aneurysms is mandatory to check for potential aneurysmal recanalization, regrowth, and rupture.

Purpose: To study the flow of blood in aneurysms., Methods: A canine model was used to study the hemodynamics of lateral, bifurcation, and terminal aneurysms with angiography and color Doppler techniques., Findings: Flow within experimental aneurysms, although not laminar, is seldom if ever turbulent, but rather is highly predictable, varying primarily according to the relationship of the aneurysm to its parent artery., Conclusions: These studies support earlier in vitro work and provide further evidence that not all aneurysms share similar stresses. A more complete understanding of these hemodynamic features will be useful in the establishment of criteria that allow recognition of those aneurysms that are more or less likely to rupture, to grow, or to thrombose.

Purpose: To investigate the hemodynamic characteristics of lateral carotid artery aneurysms in a canine model and to determine their influence on coils and balloons., Materials and Methods: Forty aneurysms were created in fourteen dogs and their hemodynamic characteristics and influence on coils and balloons were evaluated with angiography and color Doppler pre- and postplacement. Twenty aneurysms were treated with coils, eight with balloons, and 12 aneurysms served as controls., Results: The aneurysms demonstrated three distinct zones of flow: 1) an inflow zone entering at the distal aspect of the aneurysm ostium, 2) an outflow zone exiting at the proximal ostium, and 3) a central slow flow vortex. The inflow zone is a determining factor in the placement and stability of coils and balloons placed within the aneurysm and in the thrombosis of an aneurysm. The force of the inflow is considerable and can alter the shape of coils and displace both coils and balloons positioned within the aneurysm., Conclusions: Coils and balloons need to be of shapes and sizes that do not conform to the inflow and outflow zones. Filling the aneurysm and blocking or displacing the inflow zone can produce thrombosis of an aneurysm with preservation of the parent artery.

We report a case with pathologic correlation that demonstrates the magnetic resonance imaging characteristics of spinal pachymeningitis. Contrast enhanced T1-weighted images clearly demonstrated the thickened contrast enhancing meninges in a patient with progressive radiculomyelopathy who had both clinical and imaging evidence of progression of disease.

This study was designed to investigate the thrombogenicity, inflammatory response, and endothelial response to the presence of sterilized, 1-French polyethylene catheters implanted into the arterial system and subcutaneous tissues of 18 rats and two dogs. At time periods ranging from 1 week to 6 months, repeat angiography was done, the animals sacrificed, and the tissues containing the catheter removed for histologic study. In the subcutaneous tissues the catheter became encased in a very thin (less than 0.5 mm) coating of fibrous tissue with no evidence of inflammation. In large vessels, the catheter at all time periods appeared identical both angiographically and histologically to that at the time of implantation. In small to medium-sized vessels a slight increase in vessel size (25% increase in diameter of the rat iliac) was observed angiographically. On histologic evaluation, there was evidence of myointimal hypertrophy, which was asymmetrically placed, centered around the position of the catheter. There was no evidence of thrombi or of incorporation of the catheter itself into the hypertrophic tissue. In dogs and rats, an implanted 1-French polyethylene catheter is well tolerated: the animals showed no evidence of thrombotic, thromboembolic, or inflammatory complications. Myointimal hypertrophy was observed in small to medium-sized arteries, which is of unknown significance.

Patients with intracranial arteriovenous malformations (AVM) can expect significant mortality (15% to 20%) and morbidity (20% to 30%) over a 15-year to 20-year period. Recent advances in interventional neuroradiology, neurosurgery, neuroanesthesia, and stereotactic radiotherapy provide the opportunity to obliterate many of these lesions that were untreatable previously. The overall risk from treatment is estimated to be less than 50% that associated with untreated AVMs. For these reasons, it is important for the diagnostic radiologist to understand the diagnosis, natural history, treatment choices, and risks associated with patients with intracranial AVMs.

The rate of engraftment after autologous bone marrow transplantation (ABMT) is extremely variable and largely unpredictable. To identify factors influencing engraftment, we studied 35 patients with refractory germ cell tumors undergoing high-dose chemotherapy with carboplatin (900-2000 mg/m2) and etoposide (1200 mg/m2) with bone marrow rescue. Prior to the initiation of chemotherapy, bone marrow sufficient for two marrow infusions was harvested (range 0.86-4.82 x 10(8) nucleated cells per kg). All 35 patients received half of the collected bone marrow 3 days after the last dose of chemotherapy; 23 responders received a second round of the same chemotherapy followed by infusion of the second half of the bone marrow. Eighteen patients could be compared for the two transplant episodes. The "rate of engraftment" was defined as the unweighted mean of four parameters: 1) the number of days until the absolute granulocyte count surpassed 0.2 x 10(9)/liter, 2) the number of days until the absolute granulocyte count surpassed 0.5 x 10(9)/liter, 3) the number of days until the last platelet transfusion, and 4) the number of days until the reticulocyte count surpassed 25 x 10(9)/liter. No significant correlation was found between rate of engraftment and such factors as the number of nucleated cells per kg infused, the dose of chemotherapy, extent of prior chemotherapy, tumor response to the high-dose chemotherapy, age of the patient, or the days of granulocytopenic fever (all p greater than 0.20). In contrast, a close correlation was found for the number of units of platelets (p = 0.005) and red blood cells (p = 0.006) transfused following each of the two transplants. There was no significant difference between rate of engraftment after first and second transplantation. Comparison of these data with the results obtained in reported ABMT with separate harvests suggests that the characteristics of the infused marrow determine the rate of engraftment after ABMT. This model of repeated transplantation could provide an important tool for assessing the therapeutic efficacy of hematopoietic growth factors.

The objectives of this study were to investigate the consistency, patency, and natural history of a vein graft canine aneurysm model and to determine the effectiveness of various coil designs on inducing aneurysm thrombosis. Twenty-one sacculuslike aneurysms were created in mongrel dogs by anastomosing a vein pouch to the common carotid artery. The model produced wide-neck aneurysms with 100% patency. The canine vein graft aneurysm provided an excellent model for the evaluation of endovascular devices. Three types of specially designed platinum coils were placed in the aneurysms: those with simple curves, those with complex curves, and those with flower petal curves and silk fibers. These coils were placed by the endovascular route by means of microcatheters. Flower petal coils with silk fibers were effective in producing thrombosis of the aneurysms, suggesting that coils of the appropriate design may be useful in the endovascular treatment of aneurysms. The other coil designs evaluated, those with simple and complex curves without silk fibers, demonstrated insufficient thrombogenicity and spatial stability.

In an attempt to identify possible adverse effects of CNS prophylaxis (cranial radiation and intrathecal chemotherapy), we examined hypothalamic-pituitary function in 23 patients with acute lymphocytic leukemia (ALL). Of 18 patients who had received both cranial radiation and intrathecal chemotherapy, nine had abnormally low growth hormone responses to insulin-induced hypoglycemia (less than 7.0 ng/ml). Seven of the nine patients with abnormally low growth hormone responses also manifested ventricular dilatation on computed tomography (CT) brain scans, whereas only one of the nine patients with normal growth hormone responses demonstrated this CT scan finding (P = 0.015). The remaining patients, who had not received cranial radiation, had normal growth hormone responses and normal CT scans. There is significant correlation between ventricular dilatation on CT and abnormally low peak growth hormone responses following CNS prophylaxis in ALL.

The authors present a case of congenital bronchopulmonary foregut malformation with pulmonary artery blood supply and pulmonary venous drainage in a five-month-old boy.

A fatal rupture of a large paraophthalmic aneurysm 11 months following treatment with detachable balloons is described. This case illustrates the potential consequences of incomplete aneurysm obliteration with endovascular techniques and emphasizes the need for adequate posttreatment evaluation when this method is used for aneurysm therapy.

This study was designed to further assess the capabilities of MR as a tool for the diagnostic evaluation of patients with giant intracranial aneurysms, to determine MR's ability to define the degree of thrombosis present within giant aneurysms before and after treatment with balloon occlusion, and to delineate the MR characteristics of both spontaneous and induced thrombus within giant aneurysms. Nine patients with unclippable intracranial aneurysms treated by parent artery occlusion with detachable balloons were evaluated with MR, angiography, and CT. Pretreatment and posttreatment MR studies were evaluated for their ability to (1) define the size, configuration, and anatomic relationships of an aneurysm; (2) detect and characterize thrombus within an aneurysm; and (3) determine if treatment successfully caused complete aneurysm thrombosis. MR imaging does not replace angiography in either the pretreatment or the posttreatment evaluation of patients with giant intracranial aneurysms. Thrombus formation and dissolution is a complex, dynamic process. Active thrombus in incompletely thrombosed aneurysms differs from isolated organizing thrombus in completely thrombosed aneurysms. Induced and spontaneous thrombi differ in mechanisms of formation and in composition; their MR characteristics are also different. Reduction in mass effect is common after complete thrombosis of giant intracranial aneurysms.

The authors present a case of the sudden onset of hemiplegia in an eight-year-old boy secondary to a dissecting aneurysm of the right internal carotid artery and middle cerebral artery.

Seventy-one patients having clinical laboratory findings consistent with multiple sclerosis (MS) were imaged with a 1.5 tesla MR instrument using multiple spin echo sequences (TR = 2,000 ms and TE = 30, 60, 90, 120 ms). Multiple spin echo is a sensitive method for detecting MS lesions. Sixty-seven patients (94%) demonstrated lesions consistent with MS. With the exception of those located in the cortex, optic nerve and chiasm the lesions detected correlated with pathologic data. Lesions of the cerebral hemispheres, corpus callosum and cerebellum were generally multiple while lesions of the brain stem and optic tracts were generally singular. The majority of the lesions were associated with the white matter tracts of the cerebral hemispheres and brain stem.

Metastatic neoplasms to the thyroid that become clinically apparent are rare, but a patient that presents with a thyroid nodule and a history of a prior malignancy elsewhere (especially a renal neoplasm) should be thought to have a metastatic nodule first and a nodule of thyroid origin second. This report describes a 66-year-old woman who presented with a large symptomatic thyroid nodule and a history of a right nephrectomy for renal carcinoma two years previously.

Similar methods for measuring bone density using quantitative computed tomography have been proposed by Cann and Genant and by Firooznia et al. This study was done to evaluate the long-term reproducibility of quantitative computed tomography in the clinical setting. An anthropomorphic phantom was evaluated over an 18-month interval. A variation of +/- 2.2% was obtained, substantiating that quantitative computed tomography can be done in a reproducible manner over an extended time interval.

This communication presents our experience with eight patients who were initially evaluated as having normal cerebral computed tomographic (CT) scans. Follow-up scans ranging from 2 to 9 months later showed interval appearance of large contrast enhancing mass producing lesions. All eight of these patients turned out to have glioblastoma multiforme. This phenomenon of "false-negative" CT does not seem to be dependent on the type of equipment used or the age of the patient. Negative CT should not dissuade radiologists and clinicians from believing that a patient with appropriate symptoms and signs does indeed harbor a brain tumor.