Pediatric intracranial aneurysms

Cardiac chamber enlargement and hypertrophy are normal physiologic responses to repetitive endurance exercise activity in human beings and domestic dogs. Whether similar changes occur in wild animals as a consequence of increased activity is unknown. We found that free-ranging gray wolves (Canis lupus, n = 11), the archetypical endurance athlete, have electrocardiographic evidence of cardiac chamber enlargement and hypertrophy relative to sedentary captive gray wolves (n = 20), as demonstrated by significant increases in QRS duration, QT interval, and QT interval corrected for heart rate, a tendency towards increased Q, R, and S wave voltages in all leads, and a significant decrease in heart rate. We conclude that exercise activity level and therefore lifestyle affects physiologic variables in wild animals. An immediate consequence of this finding is that physiologic measurements obtained from a captive wild-animal population with reduced exercise activity level may not accurately reflect the normal physiologic state for free-ranging members of the same species.     

Anatomical and morphological factors correlating with rupture of intracranial aneurysms in patients referred for endovascular treatment

Ambulatory blood pressure (ABP) measurements were performed in a Danish population of 295 males and 275 females aged 19-21 years. Individualised day and night periods were defined from the subjects own recording of bedtime and rising on the day of their ABP measurements. During these individualised periods the ABP values for daytime, night-time and for the whole 24-h period were measured. The mean +/- s.d. values for systolic/diastolic ABP for the whole population were (124+/-11)/(70+/-7) mm Hg in the daytime, (106+/-12)/(60+/-9) mm Hg in the night-time, and (120+/-11)/(68+/-7) mm Hg in the whole 24-h period. Males had a mean systolic ABP of 9 mm Hg and mean diastolic ABP of 5 mm Hg higher than females. In males mean +/- s.d. systolic/diastolic ABP values in the daytime were (129+/-10)/(73+/-7) mm Hg, in the night-time (111+/-12)/(63+/-8) mm Hg, and in the whole 24-h period (125+/-10)/(71+/-7) mm Hg. The corresponding values in females were (119+/-10)/(68+/-6) mm Hg, (103+/-11)/(57+/-8) mmHg, and (115+/-10)/(66+/-6) mm Hg, respectively. In conclusion this study provides sex-specific normal values for ABP in a 19 to 21-year-old age group based on individualised daytime and night-time periods.     

Risk factors for developing multiple sclerosis after childhood optic neuritis

We reviewed the records of all children (younger than 16 years of age) who presented with a diagnosis of optic neuritis (ON) identified through the comprehensive records-linkage system at the Mayo Clinic and identified 94 cases between 1950 and 1988 with a documented history of idiopathic ON. Detailed follow-up information was available on 79 patients, with a median length of follow-up of 19.4 years. Life-table analysis showed that 13% of the 79 patients with isolated ON had progressed to clinically or laboratory-supported definite multiple sclerosis (MS) by 10 years of follow-up, 19% by 20 years, 22% by 30 years, and 26% by 40 years. Gender, age, funduscopic findings, visual acuity, or family history of either ON or MS did not predict the development of MS. The presence of bilateral sequential or recurrent ON increased the risk of developing MS (p = 0.002; hazard ratio = 5.09), whereas the presence of infection within 2 weeks before the onset of ON decreased the risk of developing MS (p = 0.060; hazard ratio = 0.24). This study of childhood ON supports the lower risk of recurrence and progression to MS compared with adults.     

Risk factors for multiple sclerosis: a case-control study in Israel

This case-control study was aimed at identifying environmental risk factors for multiple-sclerosis (MS). Ninety-three Israeli-born MS patients identified in country-wide studies and 94 age- and sex-matched controls were interviewed. The questionnaire covered a large span of factors at ages 0, 10 and onset of the disease, with particular emphasis on socioeconomic status (SES) and sanitary conditions (SAN). A significantly larger percentage of patients reported frequent respiratory educational levels than controls. The SES and SAN at age 10 were also systematically higher among patients, but significance was reached only when the frequencies of conditions indicating extremely low values of SES or SAN were compared. It is possible that the protective effect of low SES or SAN on risk of MS can be detected only when living conditions are well below average, as is frequent in developing countries.     

Histologic and morphologic comparison of experimental aneurysms with human intracranial aneurysms

PURPOSE: Vein pouch aneurysms are the most commonly created experimental lesions in neuroendovascular research. We sought to determine whether an experimental aneurysm that is derived from a pancreatic elastase-digested arterial sac (EDASA) models the histology and morphology of human cerebral aneurysms more accurately than the vein pouch aneurysm does. METHODS: EDASAs were created in the common carotid arteries of four rabbits, and vein pouch aneurysms were created in the common carotid arteries of four pigs. Five recently ruptured human cerebral aneurysms were obtained at autopsy. Identical histologic preparations were made for all specimens, and a vascular pathologist performed blinded histologic analyses. Morphologic dimensions were measured with a micrometer at 40-fold magnification. RESULTS: In each human cerebral aneurysm, there was complete absence of internal elastic lamina and tunica media, and none showed evidence of mural inflammation or neointimal proliferation. Average wall thickness was 51 microm. All vein pouch aneurysms had a well-developed internal elastic lamina and tunica media, and all exhibited profound inflammation and neointimal proliferation. Average wall thickness was 290 microm. EDASAs were devoid of internal elastic lamina, their tunica medias were mildly atrophic, and the sac walls contained only mild inflammation and neointimal proliferation. Average wall thickness was 46 microm. CONCLUSIONS: EDASAs model the morphologic and histologic characteristics of human cerebral aneurysms more accurately than vein pouch aneurysms do.     

Fibromuscular dysplasia and multiple dissecting aneurysms of intracranial arteries. A further cause of Moyamoya syndrome

A 16-year-old boy, who had sudden left-sided hemiplegia, died two weeks following onset of symptoms. A right carotid angiogram showed stenosis at the termination of the internal carotid artery. The middle cerebral artery had a beaded appearance and some of its branches were occluded. A basal "moyamoya" syndrome and transdural anastomoses were present. At autopsy, multiple intracranial dissecting aneurysms were found. Arteries of the body displayed fibromuscular dysplasia (FMD). The relevance of dysplastic changes of intracranial arteries and the relationship to moyamoya syndrome are discussed.     

Pantopaque simulating thrombosed intracranial aneurysms on MRI

A patient is presented in whom iophendylate (Pantopaque) within the basal cisterns closely resembled the appearance on MRI of thrombosed aneurysms of the middle cerebral arteries. The sometimes subtle differences between the appearances on MRI of Pantopaque and aneurysmal clot are discussed to permit accurate diagnosis without resorting to more invasive diagnostic tests, such as cerebral angiography.     

Long-term follow-up study of unruptured intracranial aneurysms

OBJECTIVE: The purpose of this study was to clarify the risk of rupture of unruptured intracranial aneurysms among large groups of patients with various underlying diseases or conditions. METHODS: A long-term follow-up study of unruptured intracranial aneurysms was performed with 360 patients who were treated conservatively during the period from April 1969 to December 1992. RESULTS: Follow-up evaluation (between February and June 1994) could be performed for 234 (65%) of the patients. The underlying diseases included multiple aneurysms with subarachnoid hemorrhage for 60 patients, cerebral infarction for 108, intracerebral hemorrhage for 27, and other diseases for 39. Single aneurysms were present in 171 patients and multiple aneurysms in 63. The mean follow-up period was 75 months (range, 3-270 mo). Of the 234 patients, 132 (56.4%) survived, 59 (25.2%) died because of other diseases, 9 (3.8%) underwent surgery, and 34 (14.5%) showed bleeding from unruptured aneurysms, which was fatal for 18 of the patients. The average annual rupture rate for all patients was 2.3% (subarachnoid hemorrhage, 3.2%; cerebral infarction, 2.2%; intracerebral hemorrhage, 3.2%; other diseases, 3.6%). There were no significant differences among the patients according to underlying disease or aneurysm site. The cumulative rate of bleeding for all patients was 20% at 10 years after diagnosis and 35% at 15 years. The cumulative probability of rupture was significantly higher for the multiple aneurysms than the single aneurysms (P < 0.001). CONCLUSION: The risk of rupture of unruptured aneurysms is high, especially for multiple aneurysms, but there are no significant differences in the risk of rupture according to the underlying disease or the aneurysm location. Radical treatment should be considered for patients with unruptured intracranial aneurysms.     

Screening for intracranial aneurysms in patients with isolated polycystic liver disease

BACKGROUND/PURPOSE: Cloacal exstrophy can now be managed with excellent survival rates and reasonable long-term outcomes with many of these patients living into their late teens and early adulthood. In this report, the authors describe for the first time the association of large ovarian cysts with cloacal exstrophy. METHODS: From 1974 to 1996, 12 patients with cloacal exstrophy have been treated at C.S. Mott Children's Hospital. Massive ovarian cysts developed in four of these. These patients represent the subjects of this study. RESULTS: All four patients have been followed up beyond puberty and massive ovarian cysts have developed, which have caused significant morbidity. Three patients have required surgical intervention. All the patients had reached menarche before the development of the cysts. In all cases, the presentation was severe pelvic pain. Urinary tract obstruction from the large pelvic cysts developed in three of the four. The cysts were bilateral in three of four patients and measured 8 to 10 cm in diameter on ultrasound scan or computed tomography (CT). Cyst aspiration was attempted in two cases and was unsuccessful. Three of the four patients have required bilateral salpingo-oophorectomy. The indications for surgery were uncontrollable pelvic pain in one and urinary obstruction and uncontrollable pelvic pain in two. Surgical findings demonstrated massive thin-walled cysts with essentially no normal ovarian tissue in association with duplicated mullerian structures. The pathology findings were corpus luteal cyst in two and mucinous cystadenoma in one. The fourth patient with an 8- x 10-cm unilateral cyst is being followed up. CONCLUSIONS: The authors have described, for the first time, the association of massive ovarian cysts with cloacal exstrophy. These cysts can lead to severe pelvic pain and urinary tract obstruction. Bilateral oophorectomy has been required in most of these patients.     

CTA-based angle selection for diagnostic and interventional angiography of saccular intracranial aneurysms

Coil embolization is a safe treatment for cerebral aneurysms only if the width of the neck in relation to the fundus of the aneurysm is small. Therefore, accurate visualization of the aneurysmal neck is required both in the diagnostic process and during the intervention. Conventional digital subtraction angiography (DSA) is still the preferred modality for the examination of cerebrovascular abnormalities like aneurysms, but it often does not provide the required morphological characteristics due to the suboptimal selection of projection angles and resulting overprojections of surrounding vasculature. This paper presents a method for performing a computer-assisted calculation of the optimal projection angles for DSA by post-processing computed tomographic angiography (CTA) volume data using ray-casting techniques and a combination of image processing algorithms. By means of phantom studies, retrospective simulations of angiograms, and in vivo applications of calculated optimal viewing angles, it is demonstrated that the proposed method results in better angiographic projections of the neck of saccular aneurysms with small neck-fundus ratio than those acquired at standard angles prescribed by clinical protocols.     

Mortality and morbidity of surgery for unruptured intracranial aneurysms: a meta-analysis

BACKGROUND AND PURPOSE: Greater availability and improvement of neuroradiological techniques have resulted in more frequent detection of unruptured aneurysms. Because prognosis of subarachnoid hemorrhage is still poor, preventive surgery is increasingly considered as a therapeutic option. Elective surgery requires reliable data on its risks. Therefore, we performed a meta-analysis on the mortality and morbidity of surgery for unruptured intracranial aneurysms. METHODS: Through Medline and additional searches by hand, we retrieved studies on clipping of unruptured (additional, symptomatic, or incidental) aneurysms published from 1966 through June 1996. Two authors independently extracted data. We used weighted linear regression for data analysis. RESULTS: We included 61 studies that involved 2460 patients (57% female; mean age, 50 years) and at least 2568 unruptured aneurysms (27% >25 mm, 30% located in the posterior circulation). Mortality was 2.6% (95% confidence interval [CI], 2.0% to 3.3%). Permanent morbidity occurred in 10.9% (95% CI, 9.6% to 12.2%) of patients. Postoperative mortality was significantly lower in more recent years for nongiant aneurysms and aneurysms with an anterior location; the last 2 characteristics were also associated with a significantly lower morbidity. CONCLUSIONS: In studies published between 1966 and 1996 on clipping of unruptured aneurysms, mortality was 2.6% and morbidity was 10.9%. In calculating the pros and cons of preventive surgery, these proportions should be taken into account.     

Complex intracranial aneurysms: combined operative and endovascular approaches

OBJECTIVE: Endovascular management of complex intracranial aneurysms is increasingly being considered as an alternative to standard surgical clipping. However, little attention has been paid to the complementary nature of surgery and endovascular therapy. METHODS: Between September 1992 and May 1997, 12 patients with complex intracranial aneurysms were treated with combined operative and endovascular methods. Seven patients demonstrated subarachnoid hemorrhage (two of Grade II, two of Grade III, and three of Grade IV). Five patients demonstrated unruptured aneurysms, i.e., three giant aneurysms (one vertebrobasilar junction aneurysm, one middle cerebral artery bifurcation aneurysm, and one internal carotid artery-ophthalmic artery aneurysm), one large internal carotid artery-ophthalmic artery aneurysm, and one middle cerebral artery serpentine aneurysm. Management strategies involved either surgery followed by endovascular therapy (S-E; n = 5) or endovascular therapy followed by surgery (E-S; n = 7). S-E paradigms included aneurysm exploration followed by endovascular treatment (S-E1; n = 3), partial aneurysm clipping followed by endovascular aneurysm packing (S-E2; n = 1), and extracranial-to-intracranial bypass followed by endovascular parent vessel occlusion (S-E3; n = 1). E-S paradigms included superselective angiography followed by surgical clipping (E-S1; n = 2), Guglielmi detachable coil partial dome packing followed by delayed surgical clipping (E-S2; n = 2), proximal temporary vessel balloon occlusion followed by aneurysm clipping (E-S3; n = 2), and proximal permanent vessel occlusion followed by surgical aneurysm decompression for mass effect treatment (E-S4; n = 1). RESULTS: Eleven aneurysms (92%) were completely eliminated. The remaining aneurysm was 90% obliterated and remained quiescent at the 34-month follow-up examination, despite presenting with subarachnoid hemorrhage. No patient experienced repeat bleeding (follow-up period, 23+/-28 mo). There were no deaths. One patient achieved a fair outcome (Glasgow Outcome Scale score of III); all other patients experienced excellent outcomes (Glasgow Outcome Scale score of I). In all cases, the aneurysm management paradigm chosen had a positive effect on definitive therapy. CONCLUSION: Several factors can contribute to the complexity of intracranial aneurysms. Management strategies that combine operative and endovascular techniques in a complementary way, for the best possible outcomes for these patients, can be designed accordingly.     

Transcranial power mode Doppler duplex sonography of intracranial aneurysms

Recent events have challenged our health system to increase access to and provide high quality care for patients near the end of life. Simultaneously, Medicare is developing review policies to determine eligibility for hospice patients with select noncancer diagnoses. The purpose of this study was to determine whether the proposed policies met one of their chief goals: accurate identification of patients with a less-than-six-months prognosis. Only 35 percent of 104 patients who died within six months of admission to the hospice used for this study, LifePath Hospice, met the Medicare proposed criteria for hospice eligibility. The median and mean survival time of the sample was 14 and 30 days respectively. Based on this review, it is recommended that Medicare alter their proposed review policies and not limit access to hospice eligible patients who desire and are in need of such services.     

False-negative angiograms in subarachnoid haemorrhage due to intracranial aneurysms

In occupational epidemiology, the need to consider the age factor properly influences the choice of study design and analytical techniques. In most studies, age is viewed as a potential confounder. Age is strongly associated with end points of interest in occupational epidemiology (diseases, physiological characteristics, doses of xenobiotics, etc), but to measure age as a confounder it must be associated with the exposure under study. When the exposure of interest is time related-for example, duration of employment, time since first exposure, cumulative exposure-a strong intrinsic association with age can be anticipated, and age will behave as a (usually strong) confounder. When occupational exposures without a direct relation with age-for example, job, department, type of exposure-are evaluated, the degree and direction of confounding bias cannot be anticipated. Control of the confounding effect of age can be accomplished in the design phase of a study by way of randomisation, restriction, and matching. Randomisation is seldom viable in occupational settings. Restriction is rarely used in the case of age. Matching is often used in a case-control study as a method to increase the study efficiency, but it must be followed by proper matched or stratified analysis. Options for age adjustment in the analysis phase involve stratification and regression methods. In longitudinal studies the modified life table analysis is used to take into account the fact that subjects cross categories of age as the study proceeds. Stability of relative measures of effect over age strata favoured the greater use of relative risks than risk differences. In the presence of effect modification the influence of age should not be eliminated; its interaction with exposure should be explicitly considered.     

Some observations on the microneurosurgical treatment of intracranial aneurysms

This paper reports a retrospective study of the microneurosurgical management of intracranial aneurysm in 133 patients. Good or fair results were obtained in 76%, 12% of patients had a poor result and the mortality was 12%. Major factors which were found to influence the outcome of surgery were: pre-operatively, the Botterell grade of the patient, pre-existing systemic hypertension and the time interval between the last subarachnoid haemorrhage and surgery. Post-operatively, the development of cerebral vasospasm was associated with a poor outcome from surgery. Better results might be obtained from the surgery of intracranial aneurysm by delaying operation to the second week after subarachnoid haemorrhage and by better management of hypertensive patients pre-operatively and patients who develop cerebral vasospasm post-operatively.     

Alpha-1-antitrypsin phenotypes among patients with intracranial aneurysms

A deficiency of alpha 1-antitrypsin has been implicated in the development of arterial aneurysms, including intracranial aneurysms. The authors determined the prevalence of alpha 1-antitrypsin deficiency of different phenotypes in 100 consecutive patients with intracranial aneurysms and compared the distribution of alpha 1-antitrypsin phenotypes to that in the general population (904 people). The study population consisted of 44 men and 56 women with a mean age of 52 years (range 15-81 years). The heterozygous alpha 1-antitrypsin deficiency states (PiMS and PiMZ) were more common in patients (16%) than in the general population (7%), providing an odds ratio of 2.56 (95% confidence interval (CI) 1.32-4.75; p = 0.005). In addition, one patient (1%) was homozygous for the deficient allele (PiZZ) compared to an expected number of 0.015, providing an odds ratio of 67.0 (95% CI 2.0-363.3; p = 0.015). These findings lead the authors to suggest that the heterozygous and homozygous alpha 1-antitrypsin deficiency states are genetic risk factors for the development of intracranial aneurysms.     

Double microcatheter technique for detachable coil treatment of large, wide-necked intracranial aneurysms

We describe a technique used to treat two patients with large, wide-necked aneurysms during the past 2 years. In the initial attempts at embolization, evidence of coil instability within the aneurysm or significant impingement of coil loops on the parent artery was observed. Advancement of a second microcatheter into the aneurysm allowed two coils to be braced across the aneurysmal neck before the detachment of either coil. This technique permitted successful coil treatment in both patients.