Rupture of a previously documented asymptomatic aneurysm enhances the argument for prophylactic surgical intervention

doi:10.1016/0090-3019(88)90307-2

Surgical Neurology

Volume 30, Issue 4, October 1988, Pages 321-323

https://doi.org/10.1016/0090-3019(88)90307-2 Get rights and content

Abstract

A case is presented of an incidentally discovered 6-mm aneurysm that was left untreated and subsequently produced a subarachnoid hemorrhage. The patient had no previous history of intracranial hemorrhage from any other source. A case of this type has not been previously documented in the literature. This experience points out the potential for catastrophe in small unruptured aneurysms found in patients without previous subarachnoid hemorrhage. The extremely low operative morbidity for repair of these types of lesions in otherwise healthy individuals would argue strongly for prophylactic surgery in properly selected patients.

References (14)

S Dell
Asymptomatic cerebral aneurysm: assessment of its risk of rupture
Neurosurgery
(1982)
V Eskesen et al.
Clinical features and outcome in 48 patients with unruptured intracranial saccular aneurysms: a prospective consecutive study
Br J Neurosurg
(1987)
O Heiskanen
Risk of bleeding from unruptured aneurysms in cases with multiple intracranial aneurysms
J Neurosurg
(1981)
O Heiskanen et al.
Risk of rupture of a second aneurysm in patients with multiple aneurysms
J Neurosurg
(1970)
JA Jane et al.
The natural history of aneurysms and arteriovenous malformations
J Neurosurg
(1985)
LH Rogers
Intracranial aneurysm size and potential for rupture (letter)
J Neurosurg
(1987)
JL Salazar
Surgical treatment of asymptomatic and incidental intracranial aneurysms
J Neurosurg
(1980)

There are more references available in the full text version of this article.

Cited by (27)

Microsurgical treatment of unruptured intracranial aneurysms. A consecutive surgical experience consisting of 450 aneurysms treated in the endovascular era
2007, Surgical Neurology
Citation Excerpt :
Although earlier reports advocated treating most unruptured IAs, some more recent studies have recommended treating only larger or symptomatic aneurysms because of their more aggressive natural history [5,6,8,10,17,20,21,24,35,36,43,49,56]. Nevertheless, several investigators have described the rupture of small, asymptomatic, and previously unruptured IAs that were being followed without treatment [15,22,23,35,44,48,57,58]. Clearly, unruptured IAs should be treated only if surgical and endovascular complication rates can be kept at very low levels.
With the progressive refinement of endovascular techniques, fewer IAs are being treated with open microsurgery. There is limited information regarding the impact of this trend on the ability of younger neurosurgeons to achieve proficiency in the surgical management of IAs. We describe a consecutive series of patients with unruptured IAs treated by a neurosurgeon initiating a dedicated cerebrovascular practice in the “endovascular era.”
We retrospectively reviewed the records of all patients who had undergone surgical repair of a saccular IA by one neurosurgeon upon completion of neurosurgical training in July 1997 until April 2005. Patients with ruptured IAs were excluded from review.
Of the 1450 patients with IAs treated during this period, 376 underwent microsurgical repair of 450 unruptured IAs. Microsurgical aneurysm neck clipping was possible in most cases, although distal revascularization with proximal occlusion was used in many of the more complicated aneurysms. Major complications occurred in 6 (1.60%) patients, and 1 (0.27%) patient died. At the time of 6-month follow-up, 4 (1.06%) patients were left with a new focal neurologic deficit related to surgery.
Despite the growing role of endovascular therapy in the management of IAs, it is possible for young neurovascular surgeons to achieve acceptable results with open microsurgical treatment of IAs. The factors that were deemed important in achieving success in this series included a collaborative approach with endovascular colleagues, careful surgical judgment, continual reanalysis of personal results, and early support from experienced mentors.
Pathogenesis, natural history, and treatment of unruptured intracranial aneurysms
2004, Mayo Clinic Proceedings
Citation Excerpt :
Another treatment consideration involves the performance of carotid endarterectomy in patients with unruptured aneurysms. At least 139 cases involving endarterectomy in patients with intracranial aneurysms have been reported.98–106 Among 135 patients without reported prior SAH, 5 had subsequent aneurysmal rupture at intervals ranging from 2 days to 10 months after endarterectomy.
Unruptured intracranial aneurysms (UIAs) are a major public health issue. These lesions have become increasingly recognized in recent years with the advent of advanced cerebral imaging techniques. Epidemiological evidence from multiple sources suggests that most intracranial aneurysms do not rupture. Therefore, it is desirable to identify which UIAs are at greatest risk of rupture when considering which to repair. It is important to compare size-, site-, and group-specific natural history rates with size-, site-, and age-specific morbidity and mortality associated with UIA repair because increased natural history risk often is associated with increased risk of aneurysm repair. Patient age is crucial in decision making because of its major effect on operative morbidity and mortality; however, it does not substantially affect natural history. The effect of age is most notable in patients about 50 years of age and older for open surgery and about 70 years of age and older for endovascular procedures. In general, rupture risk is lowest for patients in asymptomatic group 1 (no history of subarachnoid hemorrhage) with UIAs less than 7 mm in diameter in the anterior circulation. Surgical morbidity and mortality are most favorable for asymptomatic patients younger than 50 years who have UIAs less than 24 mm in diameter in the anterior circulation and no history of ischemic cerebrovascular disease. Endovascular morbidity and mortality may be less age dependent, and this could favor endovascular procedures, particularly in patients aged 50 to 70 years. An important issue is determining immediate vs long-term risk regarding treatment effectiveness and durability. This issue emphasizes the importance of long-term follow-up in patients after surgical and endovascular procedures.
Minimal debridement or simple wound closure as the only surgical treatment in war victims with low-velocity penetrating head injuries: Indications and management protocol based upon more than 8 years follow-up of 99 cases from Iran-Iraq conflict
2003, Surgical Neurology
During military conflicts, surviving victims traditionally underwent large enough craniectomy or craniotomy to achieve extensive debridement of the in-driven bone, shell fragments, and debris. Meanwhile, the completely as well as the partially devitalized adjacent brain tissue would also be debrided. This might have led to additional neurologic deficit or lesser degree of recovery of functions.
We studied the efficacy and safety of much more limited or even absence of surgical intervention in a selected group of wartime head-wounded patients. Among 1,150 war victims with penetrating head wounds referred to two major centers affiliated with Tehran University of Medical Sciences during the 8-year period spanning the Iran-Iraq conflict, there were 191 head-wounded patients who underwent either no surgical intervention or a very limited debridement. We have attempted to follow up as closely as possible for more than 8 years. Ninety-nine of them fulfilled the criteria to be included in this series. Close follow-up for development of cerebral infections, functional recovery, or development of new neurologic deficits and epilepsy were performed. At least 3 contrast-enhanced CT scans were taken for each patient. All patients were victims of the battle-field areas with low- to moderate-velocity missile or shell fragment injury. The Glasgow Coma Scale (GCS) scores of the patients were between 8–14 when visited by the first attending neurosurgery staff. The factors considered to be effective in the outcome analysis were the entry point, the number of the in-driven bone fragments, the retained shell fragments, the brain compartments affected, and the paranasal sinus or skull base involvement with or without cerebrospinal fluid (CSF) fistula.
There were 13 unilobar, 44 bilobar, 4 trilobar, 38 transventricular, and 3 skull base lesions. The number of retained metal fragments varied between 1 to 6. The number of retained bone fragments varied between 1 to 5 in 73 victims and more than five chips in other cases. The outcome was good (back to work) in 90 patients and poor (severely disabled) in 4. Five patients died because of severity of brain damage and meningitis. The effect of the different enumerated variables upon the outcome was measured using χ² and Fisher exact test, which was nonsignificant for all of the variables except for the orbitofacial entry point of injury (p = 0.00006).
This study seems to indicate that not only is reoperation for retained bone or shell fragments unnecessary, but surgeons having modern neuroradiological instruments available to detect the proper explanation for changes in GCS of the patients may decide not to proceed with any surgical intervention in a good number of patients. As a result of the “no surgical treatment protocol,” one can preserve cerebral tissue without exposing the patient to undue risk of seizures, infection, or death by leaving behind some or all the in-driven bone and shell fragments.
Surgery of grade "0" aneurysms. Report of 22 cases
2002, Neurocirugia
La hemorragia subaracnoidea por rotura de aneurismas continúa siendo, pese a los avances de la medicina, una enfermedad devastadora, con una mortalidad del 50% en relación con el sangrado inicial. Menos del 30% de los sobrevivientes retornan totalmente a sus tareas habituales.
Los autores presentan una serie de 22 pacientes con aneurismas grado “0”, operados en un período de 6 años, con una mortalidad del 0% y una morbilidad muy baja (menor al 5%).
Se analizan las características de los mismos y se efectúa una revisión bibliográfica, llegándose a la conclusión de que la mayoría de estos aneurismas se deben tratar, ya que los riesgos con cirugía son menores que los inherentes a los de la propia enfermedad, e incluso menores que con la terapia endovascular.
Se piensa que el progreso en el diagnóstico y en el tratamiento de estas malformaciones que no sangraron, logrará reducir la elevada cifra de morbilidad y mortalidad que actualmente presentan tras el sangrado.
Subarachnoid hemorrhage secondary to aneurysms rupture is still a devastating disease, in spite of advances of medical and surgical management. Mortality remains about 50% at the initial event, and less of 30% of survivors recover their previous level. The authors present a series of 22 patients with grade “0”, aneurysms that had not bled, operated on during a six year period, with no mortality and a very low morbidity (less than 5%).
An analysis of the cases and a bibliographic revisión is made, concluding that most of those aneurysms should be treated, for the surgical risks are lower than those of the disease itself, and also lower than those of the endovascular therapy.
lt is believed that the advances in the diagnosis and treatment of unruptured aneurysms will reduce the high morbimortality they cause after the bleeding.
The diameter-cube hypothesis: A new biophysical model of aneurysm rupture
2002, Surgical Neurology
BACKGROUND
Recent discussions on the relationship between intracranial aneurysm diameter and rupture probability have focused on the presence of an apparent critical diameter of 10 mm for aneurysm rupture. Despite the fact that many investigators have argued against the existence of this critical diameter, no one has yet proposed a viable alternative concept. In this report we present a scientifically rigorous alternative concept, that the size-specific rupture probability (RP) of an aneurysm varies as the third power of the aneurysm diameter.
METHODS
We utilized a new biophysical model of aneurysm rupture that predicts the relationship between the size-specific rupture probability of an aneurysm and the diameter (D) to be RP = kD³. We tested this hypothesis against data from two autopsy studies and one large clinical aneurysm study. Subsequently, using this D³ hypothesis and the different size distributions of aneurysms in the study populations, we predicted the variation of cumulative rupture probability (CRP) with diameter for each population.
RESULTS
Data from the autopsy studies supported the diameter-cube hypothesis, with the log-log plots of size-specific rupture probability versus aneurysm diameter from the two autopsy series yielding lines with slopes 3.54 (R² = 0.61, p < 0.12) and 3.05 (R² = 0.98, p << 0.001). Plots of cumulative rupture probability versus diameter were determined to be sensitive to the size distributions of the unruptured aneurysms in the population. Furthermore, none of the CRP plots showed evidence of a critical diameter for aneurysm rupture.
CONCLUSIONS
RP varies as the third power of aneurysm diameter, a relationship that predicts a continuous increase in RP with increasing size rather than the existence of a threshold diameter that separates low- from high-risk aneurysms. Accordingly, all aneurysms have finite risk for rupture and deserve consideration for treatment. Much of the current controversy regarding the relationship between rupture rates and diameter is a result of different size distributions in study populations rather than differences in aneurysm biology.
How to treat incidental cerebral aneurysms: A review of 139 consecutive cases
1995, Surgical Neurology

View all citing articles on Scopus

View full text

Rupture of a previously documented asymptomatic aneurysm enhances the argument for prophylactic surgical intervention

Abstract

Asymptomatic cerebral aneurysm: assessment of its risk of rupture

Neurosurgery

Clinical features and outcome in 48 patients with unruptured intracranial saccular aneurysms: a prospective consecutive study

Br J Neurosurg

Risk of bleeding from unruptured aneurysms in cases with multiple intracranial aneurysms

J Neurosurg

Risk of rupture of a second aneurysm in patients with multiple aneurysms

J Neurosurg

The natural history of aneurysms and arteriovenous malformations

J Neurosurg

Intracranial aneurysm size and potential for rupture (letter)

J Neurosurg

Surgical treatment of asymptomatic and incidental intracranial aneurysms

J Neurosurg