Biomedical subjects
Publications and source records attributed to B Richling.
The authors present an electronic database for the documentation and inter-group comparison of patients subjected to microsurgical and/or endovascular therapy of ruptured and unruptured intracranial aneurysms.
OBJECT: Whereas the removal of subarachnoid blood is possible during early-stage aneurysm surgery, this cannot be achieved in aneurysms treated by endovascular means. The levels of potential spasmogens in the cerebrospinal fluid (CSF) in patients receiving endovascular treatment might therefore be higher, with the potential for more severe post-subarachnoid hemorrhage (SAH) vasospasm. METHODS: Serum and CSF concentrations of big endothelin (ET)-1 were serially measured in patients with SAH receiving one of the following treatments: 1) early (within 72 hours of SAH) aneurysm surgical treatment (15 patients), 2) early endovascular treatment (17 patients), or 3) no intervention in the acute phase (12 patients). In patients suffering delayed infarctions higher levels of big ET-1 CSF were demonstrated than in those without infarctions (p = 0.01). In patients in whom surgery was performed in the acute phase lower big ET-1 CSF concentrations were demonstrated than in those who received embolization treatment or no treatment (p = 0.02). Subgroup analysis demonstrated that in patients receiving early endovascular treatment, higher big ET-1 CSF concentrations were revealed than in those undergoing early aneurysm surgery; this was true for patients with (microsurgerytreated, 1.84 +/- 0.83 pg/ml; and embolization-treated 2.19 +/- 0.54 pg/ml) and without (microsurgery-treated 1.76 +/- 0.61 pg/ml; and embolization-treated 2.01 +/- 0.48 pg/ml) delayed infarctions. CONCLUSIONS: Among patients with SAH who received treatment during the acute phase, those undergoing early aneurysm surgery were shown to have lower big ET-1 CSF levels than those receiving embolization and no treatment (that is, the nonsurgical treatment groups). The clinical significance of this finding remains to be established in future clinical trials, because in the present study the trend toward lower levels of big ET-1 CSF in the microsurgically treated group was not paralleled by a lower delayed stroke rate or an improvement in neurological outcome.
Carotid body tumors are rare neoplasms arising from the small chemoreceptor organ in the adventitia of the common carotid bifurcation. Patients with carotid body tumours usually present with a gradually enlarging non-tender anterolateral neck mass. Differential diagnosis includes metastatic lymph nodes, carotid artery aneurysm, salivary gland tumour, branchial cleft cyst, and neurogenic or thyroid tumours. When such a lesion is suspected, a non-invasive Doppler colour flow ultrasonography enables the clinician to arrive at a definite diagnosis. Subsequent arteriography is mandatory, because the finding of an intensely blushing hypervascular mass spreading into the carotid bifurcation further supports the diagnosis and provides accurate preoperative information concerning arterial blood supply. Computed tomography scanning is appropriate to delineate the relation of the tumour to adherent structures, while magnetic resonance tomography demonstrates the relation of the tumour to the adjacent internal jugular vein and the carotid artery. Selective embolization should be performed for safe surgical removal with less bleeding. Early surgery is the treatment of choice and is recommended in order to minimize major risks. Subadventitial resection is the most established technique. Radical resection prevents local recurrence and has the best long-term results. Removal of the internal or common carotid arteries can become mandatory in selected cases of extensive disease. Surgical treatment by an experienced team is associated with considerably low mortality and morbidity.
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.
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.
The endovascular management of brain arteriovenous malformations (AVMs) is a part of the therapeutic AVM strategy. In selected cases, endovascular therapy may lead to a total and permanent cure, but in most cases it will be an adjunctive therapy to microsurgery or radiosurgery. Embolization of brain AVMs is still a technical challenge that requires experience and skill on the part of the physician and requires a further improvement of tools, but it has made brain AVMs curable.
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.
We treated four patients with 3 recurrent and 1 residual aneurysm after surgical clipping by using Guglielmi detachable coils (GDCs). Three subjects presented after a second subarachnoid hemorrhage (SAH) occurring between 10 and 25 years after the first bleeding. Early postoperative angiography of the fourth patient showed an incompletely clipped aneurysm. In three poor grade patients we observed one good outcome, one fair result and one death due to the sequelae of SAH. One good grade patient remained in excellent condition postoperatively. Three aneurysms were totally occluded and in one a more than 90% occlusion was achieved with GDCs. We consider the treatment with GDC a viable alternative to reoperation in all patients with recurrent or residual aneurysms following failed attempt at surgical obliteration.
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.
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.
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).
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.
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.
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.
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.
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).
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.
PURPOSE: We report our experience with 42 patients with 48 cavernous carotid aneurysms, of whom 32 were treated with endovascular techniques and 10 were managed conservatively. METHODS: The 48 aneurysms were divided into two subgroups by location: 23 were at the C-3 portion of the carotid artery (small, saccular aneurysms with an epidural, partly intracavernous location) and 25 originated at the C4-5 segment (large or giant often fusiform aneurysms with a true intracavernous location). Morphologic features in both groups correlated well with differences in clinical presentation and also influenced therapy. Sixteen of the 25 C4-5 aneurysms (all large or giant) were treated by balloon occlusion of the parent artery, four (with narrow necks) were treated with Guglielmi detachable coils (GDCs), and five were not treated (asymptomatic or minimally symptomatic). Twelve of 13 C-3 aneurysms were treated with GDCs. Ten C-3 aneurysms were not treated. RESULTS: Ophthalmoplegia resolved or improved in nine of 12 patients treated with parent artery occlusion. All aneurysms treated by carotid occlusion thrombosed. Twelve of the 17 aneurysms treated with GDCs were 100% filled by the coils, four were 80% to 95% filled, and one was only 40% filled. Seven of the 100% filled aneurysms remained completely occluded, two showed slight coil compaction, and in three, follow-up angiography was not available. Among the incompletely filled aneurysms, two remained unchanged, one showed progressive thrombosis, a fourth revealed coil compaction, and in one, follow-up angiography was not available. One thromboembolic stroke and three transient ischemic attacks occurred perioperatively, for a permanent morbidity of 3.5% and a transient morbidity of 9%. There was no mortality. Mean clinical follow-up was 33 months; mean angiographic follow-up of patients treated with GDCs was 11 months. CONCLUSION: Surgically difficult cavernous aneurysms can be obliterated by embolization with excellent clinical results. Detachable coils have become an important endovascular tool, especially for narrow-necked cavernous aneurysms of the C-3 segment, which can be protected against rupture in the subarachnoid space in most cases.