Clinical and angiographic results of endosaccular coiling treatment of giant and very large intracranial aneurysms: a 7-year, single-center experience

OBJECTIVE

To evaluate whether the objectives of surgical treatment, i.e., prevention of aneurysmal rebleeding, relief of aneurysmal mass effect, and prevention of embolic complications, are met by endosaccular coiling treatment applied to giant and very large wide-necked aneurysms.

METHODS

Thirty patients with 31 giant or very large aneurysms were considered to show unacceptable risk/benefit ratios for open surgery and were treated using the Guglielmi detachable coil (GDC) method between 1992 and 1998.

RESULTS

With endosaccular GDC treatment, 73.3% of the population experienced excellent to good recoveries (Glasgow Outcome Scale scores of 4 or 5), with a 13.3% procedure-related morbidity rate and a 6.7% procedure-related mortality rate. Two hemorrhaging episodes occurred after GDC treatment (annual bleeding rate, 2.5%; 2 hemorrhaging episodes/79.2 patient-yr). Symptoms related to aneurysmal mass effect were improved for 45.5% of the patients presenting with signs of neural compression. Among 23 patients with 24 aneurysms who were available for angiographic follow-up assessment, complete or nearly complete occlusion was observed for 17 aneurysms (71%; angiographic follow-up period, 24.3 +/- 19.6 mo, mean +/- standard deviation). A single total embolization served as definitive treatment for only 12.5% of the giant aneurysms and 31% of the very large aneurysms.

CONCLUSION

Endosaccular GDC treatment of giant and very large aneurysms was accomplished with procedure-related morbidity and mortality rates comparable to those for open surgery performed by experts. However, because coil stability was unsatisfactory, we suggest that the GDC method should currently be reserved for individuals who are considered poor candidates for open surgery.

Gross and microscopic histopathological findings in aneurysms of the human brain treated with Guglielmi detachable coils

OBJECT

The histopathological characteristics of aneurysms obtained at autopsy or surgery 3 days to 54 months after being treated with Guglielmi detachable coils (GDCs) were assessed.

METHODS

Seventeen aneurysms were obtained at autopsy and one was removed at surgery. Fourteen were examined histologically with the coils in situ. Naked coils embedded in an unorganized thrombus were found in those aneurysms that had been treated with coils within 1 week earlier. An incomplete replacement of the intraluminal blood clot by fibrous tissue and a partial membranous covering at the aneurysm orifice were observed in those aneurysms that had been treated with coils between 2 and 3 weeks prior to examination. One small aneurysm treated 6 weeks before harvesting showed formation of an endothelium-lined layer of connective tissue at the orifice. Collagen-rich vascularized tissue surrounding the coils was found in an aneurysm removed at surgery 54 months after coil implantation. Interestingly, six (50%) of 12 aneurysms (two small, three large, and one giant) that had been deemed 100% occluded on initial angiography showed tiny open spaces between the coils at the neck on gross examination.

CONCLUSIONS

Endothelialization of the aneurysm orifice following placement of GDCs can occur; however, it appears to be the exception rather than the rule. In large aneurysms the process of intraaneurysm clot organization seems to be delayed and incomplete; tiny open spaces between the coils and an incomplete membranous covering in the region of the neck are frequently encountered. Further longitudinal studies are required to establish the spectrum of healing profiles that may direct our efforts in modifying the GDC system to produce a more stable long-term result.

Extracerebral organ dysfunction and neurologic outcome after aneurysmal subarachnoid hemorrhage

OBJECTIVE

To analyze the influence of extracerebral organ system dysfunction after aneurysmal subarachnoid hemorrhage (SAH) on mortality and neurologic outcome.

DESIGN

Observational study with retrospective data extraction.

SETTING

Neurosurgical intensive care unit (NICU) at a primary level university hospital, supervised and staffed by both members of the Clinic of Neurosurgery and the Clinic of Anesthesiology and General Intensive Care.

PATIENTS

Two hundred forty-two patients treated for intracranial aneurysm rupture within 7 days of the most recent SAH.

INTERVENTIONS

Routine neurosurgical interventions for obliteration of the ruptured aneurysm (microsurgery, Guglielmi Detachable Coils embolization) and for treatment of posthemorrhagic hydrocephalus (ventriculostomy, cerebrospinal fluid shunt implantation).

MEASUREMENTS AND MAIN RESULTS

Respiratory, renal, hepatic, cardiovascular, and hematologic organ system functions were evaluated both individually and in aggregate by using a modified version of the Multiple Organ Dysfunction (mMOD) score. Of 1,452 organ system functions assessed in 242 patients during their NICU stay, 714 organ system functions were intact (cerebral: 0, extracerebral: 714), 556 organ systems had mild-to-moderate dysfunctions (mMOD scoremax 1-2 for the affected organ system; cerebral: 153, extracerebral: 403), and 182 organ systems failed (mMOD scoremax 3 for the affected organ system; cerebral: 89, extracerebral: 93). Severity of extracerebral organ system dysfunctions correlated with the degree of neurologic impairment (Hunt and Hess [H&H] score) in a graded fashion. Similarly, the chance to develop systemic inflammatory response syndrome (SIRS) during the NICU stay increased with increasing admission H&H grade. The incidence of SIRS and septic shock was 29% and 10.3%, respectively. The mortality rate was 40.2% in patients with SIRS and 80% for patients suffering septic shock. Seventy-seven percent of extracerebral organ system failures (OSFs) occurred in conjunction with SIRS: 51% of respiratory OSFs, 97% of renal OSFs, 100% of hepatic OSFs, 96% of cardiovascular OSFs, and 73% of hematopoietic OSFs. Both CNS dysfunction and extracerebral organ system dysfunctions were significantly related to neurologic outcome. The probability of unfavorable neurologic outcome significantly increased with both decreasing cerebral perfusion pressure (CPP) and increasing severity of extracerebral organ dysfunction.

CONCLUSION

Aneurysmal SAH and its neurologic sequelae accounted for the principal morbidity and mortality in the current series. Development of extracerebral organ system dysfunction was associated with a higher probability of unfavorable neurologic outcome. Systemic inflammation (SIRS) and secondary organ dysfunction were the principal non-neurologic causes of death.

Treatment of basilar artery bifurcation aneurysms by using Guglielmi detachable coils: a 6-year experience

OBJECT

The authors retrospectively analyzed the results of their 6-year experience in the treatment of basilar artery (BA) bifurcation aneurysms by using Guglielmi detachable coils (GDCs).

METHODS

This analysis involved 45 BA tip aneurysms in 16 men and 29 women who ranged in age from 23 to 78 years (mean 50 years). Seventy-five percent of the aneurysms had ruptured and 25% remained unruptured. Of the group whose aneurysms hemorrhaged, 14 patients were Hunt and Hess Grade I or II and 20 were Hunt and Hess Grades III to V; 32 patients were treated within 2 weeks of their subarachnoid hemorrhage (SAH). Initially, treatment with GDCs was limited to poor-grade high-risk patients who refused surgery or patients in whom surgery proved unsuccessful. Later in the study, good-grade patients with narrow-necked aneurysms were also treated using GDCs. The length of clinical follow up ranged from 1 to 72 months (average 27.4 months) in the 37 surviving patients. In 33 of the 45 aneurysms treated with coil placement, good to excellent results were achieved. There were 12 poor results (27%) including one in a patient from the non-SAH group who suffered a thrombotic complication due to an underlying vasculitis. Eight deaths were recorded in this group of 45 patients. One of these deaths was caused by a complication related to anesthesia, one by unknown causes, and six resulted from complications of the disease. One patient rebled on the 2nd day after the endovascular procedure. The mortality and permanent morbidity rates directly related to the intervention were 2.2% and 4.4%, respectively. Angiographic studies obtained immediately postintervention demonstrated 99 to 100% occlusion in 30 (67%) of the aneurysms; nine (20%) were more than 90% occluded; and six (13%) were less than 90% occluded by the GDCs. Follow-up angiograms were obtained in 31 patients between 2 and 72 months after coil placement. Nineteen (61%) of the follow-up angiograms revealed stable results (that is, no change from initial treatment). Twelve of the 31 showed coil compaction, but only eight of these lesions could accept additional coils. In large aneurysms recanalization was seen in 57%, and some of the larger lesions required as many as four embolizations (mean 1.7) to achieve optimal occlusion. When small-necked aneurysms were analyzed as a subset, a stable angiographic result was seen in 92%.

CONCLUSIONS

Use of GDCs led to excellent clinical and angiographic results in the majority of patients with BA tip aneurysms included in this limited follow-up study. Rebleeding was encountered in one of the 34 previously ruptured BA aneurysms treated with GDCs, and no hemorrhages have been documented in the 11 unruptured aneurysms treated with GDCs in this series. Long-term follow-up studies are necessary before it is possible to compare adequately the treatment of aneurysms with coil placement to the gold standard of aneurysm clipping.

Chronic shunt-dependent hydrocephalus after early surgical and early endovascular treatment of ruptured intracranial aneurysms

OBJECTIVE

The goal of this study was to document the influence of the treatment method (early surgery versus early endovascular treatment) on the development of chronic shunt-dependent hydrocephalus in a series of 242 patients treated within 7 days after aneurysmal subarachnoid hemorrhage (SAH).

METHODS

The following parameters were prospectively recorded in a computerized database and retrospectively analyzed for association with chronic shunt-dependent hydrocephalus: 1) Hunt and Hess grade, 2) Fisher computed tomographic grade, 3) incidence of repeat SAH, 4) aneurysm location, and 5) treatment method (early surgery versus early endovascular treatment).

RESULTS

Forty of 187 patients (21.4%) who survived the SAH and its neurological and/or medical sequelae underwent definitive shunting for treatment of chronic hydrocephalus. The rate of shunt dependency was positively correlated with a higher Hunt and Hess grade (P < 0.001), a higher Fisher computed tomographic grade (P = 0.003), the occurrence of intraventricular hemorrhage (P < 0.001), repeat SAH (P = 0.003), and aneurysms arising at the anterior communicating artery (P < 0.001).

CONCLUSION

The results of the present study indicate that the treatment method used does not affect the risk of the later development of chronic shunt-dependent hydrocephalus (early surgery, 23.2% [29 of 125]; early endovascular treatment, 17.7% [11 of 62]; P = 0.45).

Evaluation of cerebral vasospasm after early surgical and endovascular treatment of ruptured intracranial aneurysms

OBJECTIVE

To document the influence of the treatment modality (early surgery versus early endovascular treatment) on measures of cerebral vasospasm in a nonrandomized series of 156 patients treated within 72 hours of aneurysmal subarachnoid hemorrhage.

METHODS

The following parameters were prospectively collected in a computerized data base and retrospectively analyzed for association with vasospasm-related ischemic infarctions: 1) Hunt and Hess (H&H) grade, 2) Fisher grade, 3) highest mean cerebral blood flow velocity (CBFVMAX) and maximum percent change in mean CBFV (%deltaCBFV) as recorded by transcranial Doppler ultrasound, 4) incidence of repeat subarachnoid hemorrhage, 5) incidence of delayed ischemic neurological deficits, 6) incidence of delayed ischemic infarctions, and 7) Glasgow Outcome Scale score.

RESULTS

Forty-one patients (26.3%) suffered ischemic infarctions. The ischemic infarction rate was correlated with higher H&H grade (P = 0.002), higher Fisher grade (P = 0.05), higher CBFVMAX (P < 0.001) and %deltaCBFV (P = 0.01), occurrence of repeat subarachnoid hemorrhage, occurrence of delayed ischemic neurological deficits, and endovascular treatment (P = 0.02).

CONCLUSION

The infarction rate was higher with endovascular treatment versus surgery (37.7 versus 21.6%), as a result of a skewed Fisher Grade 4 infarction pattern in the endovascular treatment group versus the surgery treatment group (66.7 versus 24.5%). We suspect that unremoved subarachnoid/intracerebral clots contributed to the higher infarction rate with endovascular treatment. When patients with Fisher Grade 4 and H&H Grade V were excluded from analysis, the difference in infarct incidence between the treatment groups no longer reached statistical significance (Fisher Grades 1-3, P = 0.49; H&H Grades I-IV, P = 0.96).

Diagnostic and therapeutic approaches to carotid body tumors. Review of 24 patients

OBJECTIVE

To determine the clinical characteristics of carotid body tumors to define better a standardized proceeding in the management of carotid body tumors.

DESIGN

Retrospective survey. Duration of postoperative follow-up was 4 months to 16 years (median, 57 months).

SETTING

Institutional, tertiary care medical center.

PATIENTS

Consecutive sample of 24 patients (10 men and 14 women) with 28 carotid body tumors treated in the University of Vienna (Austria) General Hospital in 35 years.

INTERVENTIONS

Surgical resection, preoperative embolization.

MAIN OUTCOME MEASURES

Initial signs, duration of symptoms, extension of the tumors, methods of investigations, and treatment modality, with special respect to the operative technique.

RESULTS

Doppler color flow imaging and angiography provided essential mainstays for definite diagnosis. Computed tomography and magnetic resonance imaging contributed additional information about tumor extension. Nineteen patients (79%) underwent surgical resection of 22 tumors, 8 (42%) after preoperative embolization. There were no perioperative deaths. Hemiplegia occurred in 1 patient, and cranial nerve palsy occurred in 5 patients. Tumor recurrence was observed in 3 patients. Five patients refused surgery or tumors were unresectable.

CONCLUSIONS

Our standard diagnostic procedure consists of establishing diagnosis by Doppler color flow sonography, angiography for detailing the vascularization of the tumor, and selective embolization to enable safer surgery with less bleeding. Early surgery is recommended to minimize major risks.

Pulmonary function and radiographic abnormalities related to neurological outcome after aneurysmal subarachnoid hemorrhage

OBJECT

This observational study is based on a consecutive series of 207 patients with aneurysmal subarachnoid hemorrhage who were treated within 7 days of their most recent bleed. The purpose of the study was to evaluate the effect of respiratory failure on neurological outcome.

METHODS

Pulmonary function was assessed by determination of parameters describing pulmonary oxygen transport and exchange, by using composite scores for quantification of lung injury (lung injury score [LIS]) and mechanical ventilator settings (PIF score). Pulmonary function was related to the Hunt and Hess (H & H) grade assigned to the patient at hospital admission (p < 0.001). The pattern and time course of lung injury differed significantly between patients with H & H Grade I or II, Grade III, and Grade IV or V. Hunt and Hess grade, Fisher computerized tomography grade, intracranial pressure, cerebral perfusion pressure, LIS, ratio of PaO2 to the fraction of inspired oxygen (FiO2), and the ratio of the alveolar-minus-arterial oxygen tension difference (AaDO2) to FiO2 were related to neurological outcome (p < 0.001). The LIS on the day of maximum lung injury remained an independent predictor of outcome (p = 0.01) in a stepwise logistic regression analysis. The probability of poor neurological outcome significantly increased with both decreasing cerebral perfusion pressure and increasing severity of lung injury.

CONCLUSIONS

The overall mortality rate was 22.2% (46 of 207 patients). Subarachnoid hemorrhage and its neurological sequelae accounted for the principal mortality in this series. Medical (nonneurological and nontreatment-related) complications accounted for 37% of all deaths. Systemic inflammatory response syndrome with associated multiple organ dysfunction syndrome was the leading cause of death from medical complications. The authors conclude that respiratory failure is related to neurological outcome, although it is not commonly the primary cause of death from medical complications.

Preoperative embolization of hypervascular skull base tumors

The purpose of the present study is to review the results and complications of preoperative embolization of hypervascular skull base tumors at a neurosurgical center with a team of neurosurgeons cross-experienced in the application of both microsurgery and endovascular techniques. One hundred and twenty-eight endovascular approaches were performed in 66 patients treated for skull base meningiomas (n = 41), paragangliomas of the temporal bone (n = 18), and juvenile nasopharyngeal angiofibromas (n = 7). One death and 2 permanent disabilities were attributable to endovascular therapy. These complications occurred early in our experience (1982-1989) and were related to thromboembolic events rather than complications of transcatheter embolization itself. Our current standard is to perform transfemoral superselective embolizations with either finely corpuscular embolizing substances (PVA particles) or cyanoacrylates (NBCA) under local anesthesia. Using this protocol no embolization-related complications have occurred over the last 9 years. We thus conclude that preoperative embolization of hypervascular skull base tumors can be accomplished safely with the endovascular techniques now available.

Early Clinical Outcome of Patients with Ruptured Cerebral Aneurysms Treated by Endovascular (GDC) or Microsurgical Techniques

Over the past 3.5 years 220 patients with aneurysmal subarachnoid hemorrhage were treated in the Department of Neurosurgery University of Vienna Medical School using either endovascular techniques (Guglielmi Detachable Coils) or open craniotomy with aneurysm clipping.

A retrospective analysis was undertaken to assess whether any difference in outcome could be correlated with the treatment choice.

The patients were stratified as to 1) Hunt and Hess grade at time of treatment, 2) method of treatment, and 3) clinical outcome at 2–4 weeks following treatment.

The outcomes in this population of patients were consistent with recent published series regardless of whether the aneurysms were treated with microvascular surgery or endovascular surgery.

There was a trend toward better outcome in a relatively small sub-group of patients presenting as Hunt and Hess grade III who were treated by the endovascular method. Guglielmi detachable coils have been available for a relatively short time, and although early results are promising, the ultimate long-term efficacy of the coils will have to be assessed.

Long-term functional effects of aneurysmal subarachnoid haemorrhage with special emphasis on the patient's view

Although physical and emotional dysfunction appears to be quite frequent even among independent survivors of aneurysmal subarachnoid haemorrhage (SAH), these symptoms may easily be missed on routine follow-up examinations. To assess the long-term functional effects of SAH and to outline possible treatment approaches, a cross-sectional study using multidimensional measures of relevant areas of function was performed on 40 independent survivors. After an average follow-up period of 22 months, patients were selected and enrolled following a pre-designed protocol. The comprehensive test battery consisted of subjective and objective measures of physical, psychological and social function and relationships between the different levels of assessment were calculated. We found a considerable proportion of cognitive, emotional and physical dysfunction in this sample, but on the subjective level, the majority of the patients stated satisfaction with life in general. Mild cognitive dysfunction was frequently missed and causes distress in the family. Mild to moderate depression was underdiagnosed, although such an emotional dysfunction influences working capacity and quality of life. Referral to rehabilitation centers appears to be restricted to patients with severe impairments. Our results help to alert the neurosurgeon to these possible symptoms and show the urgent need for a prospective, interdisciplinary and multidimensional follow-up of SAH survivors.

Preoperative embolization of intracranial meningiomas: a 17-years single center experience

The purpose of the present report is to review the evolution of endovascular therapy at our center as utilized for the preoperative embolization of intracranial meningiomas over a 17-years period (1982-1998). This study is based upon a consecutive series of 63 patients who underwent preoperative embolization of intracranial meningiomas. Total or subtotal angiographic devascularization of the tumor parenchyma was accomplished in 38 patients (60.3%) who had tumors with either an external carotid artery supply only (n = 30) or with contributions from the cavernous carotid artery, ophthalmic artery, vertebral artery, or pial feeders which were feasible for selective embolization (n = 8). Partial tumor embolizations were attained in the remaining 25 patients (39.7%) because 1. the remanent feeders were considered easily accessible to surgical control in the early stages of dissection, 2. the feeding branches were inaccessible for a microcatheter approach, or 3. superselective microcatheter positions allowing for safe embolization without reflux of embolic material into physiological branches were not achieved. Overall, 97 of 126 tumor feeders identified angiographically were catheterized to selective embolization (77%). Three embolization related complications occurred early in our experience (1982-1989) using techniques which no longer meet standards of treatment. In light of the remarkable evolution of endovascular techniques over the 17-years study period, however, we conclude that preoperative embolization of intracranial meningiomas can be performed safely with the endovascular tools currently available.

GDC-system embolization for brain aneurysms - location and follow-up

GDC (Guglielmi detachable coil)-embolization for the treatment of brain aneurysms was first published by Guglielmi in 1991 and has become an integral part of the treatment strategy for cerebral aneurysms in many places around the world. Low morbidity and mortality rates are set against the limited possibilities of aneurysm neck occlusion, especially in large necked aneurysms. Depending on the architecture and on the kind of coil distribution, recanalization of the neck is more or less frequent. Nevertheless, rebleeding rates are low. In our series of 211 brain aneurysms from March 1992 to June 1994, 74 (35%) patients underwent GDC-embolization. 4 patients received combined treatment (GDC-embolization and subsequent surgery). Follow-up angiography was performed on 41 patients (55%) at periods of 6, 12, and 24 months (mean follow-up 8 months). To demonstrate the results in a graphic display, the aneurysms were grouped according to location and size. The analysis of the follow-up results shows the highest occlusion stability in aneurysms of the basilar tip, followed by aneurysms of the PICA origin, the basilar trunk and the PCA. Less stability was obtained in aneurysms of the PCom followed by MCA, Acom and aneurysms of the internal carotid (C1, ophthalmic). Aneurysms of the posterior circulation show generally better results than those located in the anterior circulation. This makes (in combination with the increased surgical difficulties of aneurysms in the posterior fossa) the GDC-treatment especially useful for posterior circulation aneurysms.

Extensive facial vascular malformations and haemangiomas: a review of the literature and case reports

We present 6 selected cases of extensive facial vascular anomalies extending to the skull base or actually involving it. These patients are compared with other cases in the literature. The spontaneous course of these vascular lesions is different and so variable treatment modalities are suggested depending on the age of the patient and the type of lesion. In young children, haemangiomas are common and spontaneous involution is characteristic. Conservative treatment in the sense of a wait-and-see approach is thereby favoured if there is no urgent indication such as involvement of essential structures, e.g. blockage of an orifice as demonstrated in one case or complications such as excessive bleeding. Vascular malformations most commonly appear in adults, there is no tendency to spontaneous involution and resection is usually necessary, especially in arteriovenous malformations. Nowadays, preoperative superselective embolization is recommended to minimize intraoperative blood loss. Superselective embolization is the treatment of choice in cases of a-v fistulae. Proximal ligation of the supplying arteries should be avoided because this may make embolization more difficult, and may be responsible for the common occurrence of rapid revascularization.

Treatment of post-traumatic carotico-cavernous fistulae using electrolytically detachable coils: technical aspects and preliminary experience

We treated six patients with post-traumatic cavernous carotid fistulae by electrothrombosis using Guglielmi's new electrolytically detachable coils. The transarterial endovascular route was chosen in five and the transvenous in one case. Exophthalmos, chemosis and/or an audible bruit disappeared immediately after therapy or in the following month in all patients suffering from these symptoms. Third and sixth cranial nerve palsies resolved in three of four patients. Clinical results were excellent in three, good in two and fair in one. In this last patient massive thrombosis of an enormously dilatated superior ophthalmic vein occurred after treatment of a giant longstanding fistula, leading to unilateral visual impairment and increased sixth nerve palsy. In our first patient the intracavernous carotid artery was occluded by balloons after coil embolisation because of improper coil position and the fear of possible thromboembolic events. Angiographic cure was demonstrated in all cases by angiograms 1-6 months after therapy. The characteristics of these new coils are easy use, manoeuvreability and retrievability. They conform ideally to the shape of the vessel lumen to be obliterated and produce practically no trauma to the vessel walls. Furthermore, they can be positioned in the sinus close to the orifice of the fistula. In the last two cases partial occlusion of the fistula was sufficient to initiate the process of complete thrombosis, and delayed, complete occlusion was observed after 1 month. In our opinion this new device is not only a major contribution to treatment of intracranial aneurysms, but may also improve the results of treatment of carotico-cavernous fistulae.

False aneurysms of the intracavernous carotid artery--report of 7 cases

We present 7 cases of false intracavernous carotid artery aneurysms. Four occurred after trauma and three were caused iatrogenically. Two of the latter occurred in patients with pituitary adenomas, one after transsphenoidal microsurgery and the other after yttrium [YI90] seed implantation into the sella. The third iatrogenic aneurysm was seen shortly after transcavernous tumour surgery. In five of our seven patients massive, delayed, life-threatening epistaxis was the leading symptom. All traumatic cases were associated with immediate unilateral blindness or blurred vision and with skull base fractures. One of these had a concomitant carotid cavernous fistula. Treatment of choice of our 5 recent cases was permanent balloon occlusion of the intracavernous carotid artery at the level of the lesion. Collateral circulation was evaluated prior to definitive carotid occlusion using a balloon test occlusion. During the balloon test adequate collateral circulation was defined as symmetric angiographic filling of both hemispheres. Awake patients were neurologically examined continuously. In unconscious patients transcranial Doppler sonography, electroencephalographic and somatosensory evoked potential monitoring was used in addition. Intra-operative heparin administration was not reversed with protamin. A postoperative continuous heparin infusion was not found necessary. In our two early cases this technique was not available: In the first case we accomplished aneurysm occlusion by a surgically introduced Fogarty balloon catheter. Our second patient needed surgical trapping of the involved carotid after early unsuccessful attempts of selective aneurysm occlusion. After treatment no further epistaxis occurred. Follow-up angiography showed persistent aneurysm occlusion. The results were excellent in 5 cases and good in 1 case. One patient with bilateral lesions suffered a stroke after occlusion of the second, remaining carotid artery, despite functioning bilateral extra-intracranial bypasses. Four years later there is a mild dysphasia still present in this patient. The mean follow-up time was 75.6 months.

Histopathological findings in experimental aneurysms embolized with conventional and thrombogenic/antithrombolytic Guglielmi coils

We studied the short- and long-term histological responses induced by conventional and modified electronically detachable coils (GDCs) in experimental aneurysms. Eighteen carotid bifurcation aneurysms were produced microsurgically in rabbits. Six animals each were treated either with conventional or with GDCs coated with a mixture of tissue-thromboplastin to enhance intra-aneurysmal thrombus formation and of plasminogen activator inhibitor type-1 (PAI-1) in inhibit intra-aneurysmal clot fibrinolysis. Six served as untreated controls. Follow-up angiograms were obtained immediately and at 3, 6, 9, 12, 17, and 24 weeks after embolization prior to sacrifice of the animals. All aneurysms were studied macroscopically and histopathologically with the coils in situ. Five of six control aneurysms remained patent. Endovascular occlusion rates between > 90% and 100% were achieved in nine of twelve coiled aneurysms. Follow-up angiography demonstrated recanalization and coil compaction in 5 of them. Gross and microscopic histopathological examination revealed a membrane covering the orifice, intra-aneurysmal scar formation, and development of a neo-intima in both treatment groups at 17 and 24 weeks postembolization. The granulation tissue response appeared to be equally distributed in aneurysms treated with either uncoated or coated coils. Further quantitative morphometric studies are needed to prove if a thrombogenic/antithrombolytic coil-coating might be of value in providing a more enduring anatomic result after GDC-treatment of human brain aneurysms.

Endothelial lesions after temporary clipping. A comparative study

The effect of temporary clipping on the arterial endothelium of rats was examined with scanning electron microscopy. The opening pressure of four Heifetz clips was modified by changing the springs. Four different clip forces (20, 35, 45, and 65 gm), four periods of clipping (10, 30, 60, and 180 minutes), and three vessel diameters (smaller than 1 mm, 1.1 to 1.3 mm, and 1.4 to 2 mm) were compared. Different grades of endothelial damage were observed. On gross examination the damage involved a detachment of endothelium and the adherence of platelets to the subendothelial tissue. The duration of clipping seemed to be of more importance than the clip force, whereas the vessel diameter had no recognizable influence.

Comparative analysis between epidural (Gaeltec) and subdural (Camino) intracranial pressure probes

The new fiberoptic Camino system has recently been introduced for clinical intracranial pressure (ICP) monitoring. We compared the subdural Camino system with the well-established epidural Gaeltec system in both in vitro and clinical conditions. In the in vitro experiments the intracranial vault was simulated by a tightly closed, fluid-filled box (0.9% sodium chloride) with the two probes inside. We simulated pulsating waveforms with a jet ventilator. No difference between the simulated curve patterns and values could be detected. In the clinical studies, both probes were implanted in 10 patients who had either head injuries, subarachnoid hemorrhage, or intracerebral hemorrhage. The in vivo comparison revealed no significant difference between the two systems in the recorded pressures in group 1 (ICP less than 20 mm Hg). The subdurally placed Camino probe showed insignificantly lower ICP values than did the extradural Gaeltec probe. Although group 2 (ICP greater than 20 mm Hg) waveforms were nearly identical, significant differences (p less than 0.01) in pressure measurements (systolic, diastolic, and mean) occurred (Camino, 18 +/- 3 mm Hg; Gaeltec, 27 +/- 3 mm Hg). Correlation coefficients for mean ICP values were 0.82 in group 1 and 0.49 in group 2. Problems with the Camino probe were usually mechanical and occurred in 2 patients. The problems were either easy to recognize or manifested as an ostensibly pathologic curve. No infection occurred with either system during or following implantation. The dissimilar characteristics of the two probes can be ascribed to their different extradural and subdural implantation sites. The Gaeltec probe was more durable over the period of implantation, which averaged 98 hours and ranged from 44 to 298 hours.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of sufentanil on intracranial pressure in neurosurgical patients

The effects of sufentanil on intracranial pressure, mean arterial pressure, cerebral perfusion pressure and heart rate were studied in 20 neurosurgical intensive care unit patients. Epidural intracranial pressure probes were implanted in patients who suffered head injury, intracerebral haemorrhage or underwent tumour resection. Sufentanil was given intravenously in sequential doses of 0.5, 1.0 and 2.0 micrograms/kg. Fifteen minutes elapsed after each dose. The patients were allocated to either group 1 (baseline intracranial pressure less than 20 mmHg) or group 2 (baseline intracranial pressure greater than 20 mmHg). Intracranial pressure did not change significantly in either group. Therefore the falls in mean arterial pressure with the highest dose in both groups and with 1.0 micrograms/kg in group 2, closely reflect corresponding reductions in cerebral perfusion pressure. As sufentanil in itself exerts no effects on intracranial pressure, concomitant haemodynamic changes are the critical factor for an adequate cerebral perfusion pressure.

Homologous controlled-viscosity fibrin for endovascular embolization. Part I. Experimental development of the medium

The author used a two-component adhesive (homologous fibrinogen and thrombin) to develop a medium with controllable rate and extent of setting and coagulation. After mixing with the radiopaque substance metrizamide, the material meets the criteria postulated for an endoarterial embolization medium: variable and controllable viscosity, elasticity after setting, absence of toxicity, radio-opacity, and adequate sterilizability. After setting, the fibrin medium is a clear, solid, but soft elastic substance clearly visible on the X-ray film even in fine structures.

Evolution of different therapeutic strategies in the treatment of cranial dural arteriovenous fistulas--report of 30 cases

30 cases of cranial dural arteriovenous fistuals, treated between 1983 and 1992, are reported. Twelve presented with an aggressive clinical course including intracranial haemorrhage, progredient neurological deficit, medically intractable seizures, and cerebellar symptoms. The other 18 patients had a more benign clinical presentation with audible bruit, exophthalmus, chemosis, and cranial nerve dysfunction. One of the latter had symptoms of pseudotumour cerebri due to sinus occlusion with contralateral sinus stenosis. The most common location was at the transverse sinus, followed by the cavemous sinus, the tentorial ring, and the orbita. Four vessel angiography verified the diagnosis and demonstrated all fistulas, mainly supplied by branches of the external carotid artery. 16 of 18 benign lesions were treated by endovascular therapy alone. Two recent patients received adjuvant stereotactic radiosurgery. Among these 18 patients 2 remained untreated, one because of spontaneous fistula thrombosis prior to therapy and one because of poor medical condition. 12 of 16 treated benign dural fistulas were partially occluded. In 6 of them spontaneous fistula thrombosis occurred during the following months. Total endovascular obliteration was achieved in the remaining 4 patients. 7 of 12 aggressive fistulas were embolized only, one of them having additional radiosurgery. Two of them were totally obliterated and five partially. Surgery was performed in the remaining 5 aggressive fistulas. Complete microsurgical excision was achieved in 2 and partial in further two, who presented initially with a life-threatening intracerebral clot. In one early case ligation of the external carotid artery was done, which is now obsolete. Over all 20 of 28 treated patients became asymptomatic or improved clinically. 3 of the remaining 8 patients were unchanged, two deteriorated despite therapy, and 3 worsened after therapy. All of the latter complications occurred early in our series due to thromboembolic events during the procedure. One surgical patient suffered from a new facial nerve palsy postoperatively. Follow up time in all treated patients was between 1 and 139 months with a mean of 48,3 months.

Experimental bifurcation aneurysm: a model for in vivo evaluation of endovascular techniques

An experimental aneurysm model for in vivo testing of endovascular techniques is described. The aneurysm is produced surgically in the neck of the rabbit by partial anastomosis of the left to the right common carotid artery, thus creating an arterial bifurcation. Subsequently, a venous pouch is sutured into the artificial bifurcation. The size of the arteries, coagulation profile and hemodynamic features in this aneurysm model closely mimic human conditions. Surgical technique and our preliminary experience with this model are discussed.

Recurrent aneurysmal subarachnoid haemorrhage: bleeding pattern and incidence of posthaemorrhagic ischaemic infarction

This report is based on a consecutive series of 162 patients with aneurysmal subarachnoid haemorrhage (SAH), including 22 patients (14%) with recurrent SAH, who were treated within 72 h after the most recent bleed. Of the 22 patients with recurrent haemorrhage: 68% were in poor clinical condition (Hunt & Hess grade 4-5); 73% presented with intracerebral haemorrhage (ICH); 41% developed delayed ischaemic infarctions from chronic arterial spasm; 14% made a good recovery, while 41% died. Of the 140 patients with a single bleed: 34% were in poor clinical condition (Hunt & Hess grade 4-5); 33% presented with ICH; 22% developed delayed ischaemic infarctions; 53% made a good recovery, while 19% died. Our results suggest that a high incidence of intracerebral haemorrhage in conjunction with a more severe course of chronic arterial spasm substantially contributes to the high morbidity and mortality associated with recurrent SAH. In poor grade patients not suitable for acute open surgery, endovascular treatment should receive consideration for the prevention of early rebleeding.