International Journal of Vascular MedicineVolume 2012 (2012), Article ID 753596, 19 pagesdoi:10.1155/2012/753596

Review Article

Management of Patients Presenting with Acute Subdural Hematoma due to Ruptured Intracranial Aneurysm

Serge Marbacher, Ottavio Tomasi, and Javier Fandino

Department of Neurosurgery, Kantonsspital Aarau, 5001 Aarau, Switzerland

Received 12 September 2011; Revised 14 November 2011; Accepted 28 November 2011

Academic Editor: Mark Morasch

Copyright © 2012 Serge Marbacher et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract.

Acute subdural hematoma is a rare presentation of ruptured aneurysms. The rarity of the disease makes it difficult to establish reliable clinical guidelines. Many patients present comatose and differential diagnosis is complicated due to aneurysm rupture results in or mimics traumatic brain injury. Fast decision-making is required to treat this life-threatening condition. Determining initial diagnostic studies, as well as making treatment decisions, can be complicated by rapid deterioration of the patient, and the mixture of symptoms due to the subarachnoid hemorrhage or mass effect of the hematoma. This paper reviews initial clinical and radiological findings, diagnostic approaches, treatment modalities, and outcome of patients presenting with aneurysmal subarachnoid hemorrhage complicated by acute subdural hematoma. Clinical strategies used by several authors over the past 20 years are discussed and summarized in a proposed treatment flowchart.

1. Introduction

Rupture of a cerebral aneurysm normally results in subarachnoid hemorrhage (SAH) and is often complicated by intracerebral hematoma (ICH), but only on rare occasions does it cause acute subdural hematoma (aSDH) [1]. Diagnosis of aneurysmal SAH can be difficult in comatose patients in whom loss of conscious due to aneurysm rupture results in or mimics a traumatic brain injury [2]. Determining a differential diagnosis and treatment modalities can further be complicated by the rapid clinical course and the mixture of symptoms due to the ruptured aneurysm and the mass effect of the hematoma.

Rapid decision making is required to treat this life-threatening condition. The majority of patients with aneurysmal SAH and coincidental acute subdural bleeding present in a severe clinical condition, and immediate surgical management is required [2–4]. Decisions to be made include whether preoperative diagnostic studies should precede surgery and whether obliteration of the aneurysm should be performed during hematoma evacuation or in a separate delayed intervention after resuscitation procedures.

The incidence of combined SAH and aSDH varies from 0.5% [5, 6] to 10% [7] in clinical series. The rarity of aneurysmal aSDH makes it difficult to design reliable clinical treatment guidelines. Large systematic series do not exist, and thus treatment decisions are mainly based on personal experience. The aim of this review is to propose a management flow chart and protocol based on published experience with such cases over the past two decades.

2. Materials and Methods

2.1. Search Strategy

The literature was screened for case studies of acute subdural hematoma secondary to ruptured intracranial aneurysm. Articles for this review were identified by MEDLINE PubMed database searches of the literature from January 1990 through December 2009 using the terms “acute subdural hematoma,” “subarachnoid hemorrhage,” and “cerebral aneurysm” (by using the Boolean operator AND) (Table 1). The senior author independently assessed the reproducibility of the search strategy on August 30, 2010, two days after the first author’s search. Cross-references were checked in each eligible article.

Table 1: Search Strategy*.

Search number
Process description
Results

(“key words”)
(no. of articles)

no. 1
Search “cerebral aneurysm”
22944

no. 2
Search “subarachnoid hemorrhage”
17883

no. 3
Search “subdural hematoma”
7732

no. 4
Search #1 AND #2 AND #3
155

no. 5
Search “01/1990–12/2009” AND #4
85

*All searches for this study were performed on August 28, 2010, by the first author and verified by the second author on August 30, 2010. The publication date limits were set to January 1990–December 2009.

2.2. Selection Criteria

Articles were excluded based on title and abstract because they (i) were not written in the English language, (ii) were technical notes or laboratory investigations, or (iii) were not peer-reviewed/original studies. The remaining articles were selected for inclusion if the patients were adults and the single cases or case series provided detailed descriptions of clinical characteristics and patient management.

2.3. Data Acquisition

From selected cases, we extracted the following characteristics and recorded them in a data sheet: age; gender; initial clinical findings, including Glasgow Coma Scale (GCS) [8] score, clinical SAH grade based on the Hunt and Hess (H&H) [9, 10], and the World Federation of Neurological Surgeons (WFNS) [11] classifications; presence of major (aphasia, hemiparesis, or hemiplegia) and minor (cranial nerve palsies) focal neurological deficits, hemodynamic situation at the time of admission; radiological assessment, including computed tomography (CT) scan, CT angiography (CTA), magnetic resonance imaging (MRI), MR angiography (MRA), and digital subtraction angiography (DSA); additional presence of SAH, intracerebral hematoma (ICH); side and size of aSDH and associated midline shift; aneurysm size and location; case management; outcome according to the Glasgow Outcome Scale (GOS), modified Rankin Score (mRS), and Barthel index (BI).

3. Results

The initial search retrieved 85 publications which matched the terms “cerebral aneurysm” AND “subarachnoid hemorrhage” AND “acute subdural hematoma.” 59 publications were excluded after screening of titles and abstracts. This left 26 articles potentially eligible for detailed evaluation. Six articles were not included as they did not match the selection criteria. The remaining 20 articles including 82 cases underwent detailed analysis [2–4, 12–14, 16–26, 28–30]. Characteristics of the 82 cases are summarized in Table 2. Graphs displaying the analyzed data appear in Figure 1.

Table 2: Patient characteristics*.

Series/year of publication
Case no.
Age/sex
Initial clinical findings
Initial diagnostics
SAH
ICH
Side of aSDH
Size of aSDH
MLS
Location of aneurysm
Size of aneurysm
Management (hours from ictus)
Outcome

Watanabe et al. [30]/1991
1
51/m
WFNS 5, GCS 4, decerebrate posture, bilaterally dilated fixed pupils ataxic breath
CT scan
No
No
Lt
—
—
Lt Pcal (ACA)
—
Emergency craniectomy and hematoma evacuation (1 h)
Deceased, GOS 1, mRS 6

Watanabe et al. [30]/1991
2
72/f
WFNS 4, GCS 12, right hemiparesis
CT scan, DSA
Yes
No
Lt
—
—
Rt Pcal (ACA)
—
Clipping (on day 15)
Returned to normal daily life, GOS 5, mRS 1

Watanabe et al. [30]/1991
3
74/f
WFNS 5, GCS 4, decerebrate posture, ataxic breath, dilation of the left pupil
CT scan, DSA failed
Yes
No
Rt
—
—
Lt Pcal (ACA) (found at autopsy)
—
Inoperable
Deceased (3 days after onset), GOS 1, mRS 6

Kamiya et al. [5]/1991
4
67/f
H&H IV, paresis
CT scan, DSA
Yes
No
—
—
—
MCA
30 mm
Craniotomy, hematoma evacuation, and immediate clipping
Vegetative state, GOS 2, mRS 5

Kamiya et al. [5]/1991
5
50/f
H&H III
CT scan, DSA
Yes
Yes
—
—
—
ICA
28 mm
Inoperable because of rerupture on admission
Decubitus and pneumonia, deceased, GOS 1, mRs 6

Kamiya et al. [5]/1991
6
67/f
H&H V, paresis
CT scan, DSA
Yes
Yes
—
—
—
MCA
4 mm
Inoperable
Deceased (on arrival), GOS 1, mRs 6

Kamiya et al. [5]/1991
7
52/f
H&H V
CT scan, DSA
Yes
Yes
—
—
—
Not detected
—
Inoperable
Deceased (on arrival), GOS 1, mRs 6

Kamiya et al. [5]/1991
8
69/f
H&H II
CT scan, DSA
Yes
Yes
—
—
—
Acom
27 mm
Inoperable because of severe spasm on admission
Deceased, GOS 1, mRs 6

Kamiya et al. [5]/1991
9
63/f
H&H II
CT scan, DSA
Yes
No
—
—
—
MCA
4 mm
Craniotomy, hematoma evacuation, and immediate clipping
Good recovery, GOS 5, mRs 1

Kamiya et al. [5]/1991
10
73/m
H&H IV, paresis
CT scan, DSA
Yes
No
—
—
—
Acom
7 mm
Clinical deterioration, no operation impossible
Deceased, GOS 1, mRs 6

Kamiya et al. [5]/1991
11
64/m
H&H V, preoperative rerupture, cardiac failure
CT scan, DSA failed
Yes
No
—
—
—
Not detected
—
Inoperable
Deceased (nonfilling state DSA), GOS 1, mRs 6

Kamiya et al. [5]/1991
12
72/f
H&H IV, paresis
CT scan, DSA
Yes
Yes
—
—
—
Distal ACA
4 mm
Hematoma evacuation and immediate clipping
Good recovery, GOS 5, mRs 1

Kamiya et al. [5]/1991
13
70/m
H&H IV, paresis
CT scan, DSA
Yes
Yes
—
—
—
MCA
6 mm
Hematoma evacuation and immediate clipping
Good recovery, GOS 5, mRs 1

Kamiya et al. [5]/1991
14
72/f
H&H V
CT scan, DSA
Yes
Yes
—
—
—
ICA
4 mm
Inoperable
Deceased (day 1), GOS 1, mRs 6

Kamiya et al. [5]/1991
15
59/m
H&H V
CT scan, DSA
Yes
Yes
—
—
—
MCA
22 mm
Inoperable
Deceased (day 2), GOS 1, mRs 6

Kamiya et al. [5]/1991
16
39/f
WFNS 5, GCS 4, decerebrate posturing, dilation of the right pupil
CT scan, DSA
Yes
Yes
—
—
Moderate to marked
Distal ACA
3 mm
Hematoma evacuation and immediate clipping
Good recovery, GOS 5, mRs 1

Kamiya et al. [5]/1991
17
71/f
H&H III
CT scan, DSA
Yes
Yes
—
—
—
Acom
11 mm
Hematoma evacuation and immediate clipping
Good recovery, GOS 5, mRs 1

Rusyniak et al. [12]/1992
19
74/f
WFNS 5, GCS 4, decerebrate posturing, bilaterally miotic pupils
CT scan, CTA
Yes
Yes
Rt
—
—
Rt ICA-Pcom
—
Hematoma evacuation, immediate clipping
Complete recovery, GOS 5, mRS 1

Ragland et al. [13]/1993
20
27/m
GCS 5 right pupil nonreactive left mydriasis
CT scan, DSA
No
no
Rt
—
Moderate to marked
Acom
20 mm
Hematoma evacuation, Maximal medical treatment
Deceased, GOS 1, mRS 6

O’Sullivan et al. [3]/1994
21
32/m
WFNS 5, GCS 4, bilaterally fixed pupils, hypertensive with bradycardia
CT scan
Yes
—
Lt
—
—
Lt ICA-Pcom
12 mm
Mannitol, without effect on pupillary response (3 h), died before decompression
Deceased, GOS 1, mRS 6

O’Sullivan et al. [3]/1994
22
48/f
WFNS 5, GCS 4, dilated unreactive pupils, unstable cardiopulmonary situation
CT scan, DSA
Yes
Yes
Rt
—
—
Rt ICA-Pcom
15 mm
Manitol, without effect on pupillary response, hematoma evacuation, and clipping of the aneurysm (7 h)
Deceased, GOS 1, mRS 6

O’Sullivan et al. [3]/1994
23
36/f
WFNS 5, GCS 3, bilaterally fixed pupils
CT scan, DSA
Yes
Yes
Rt
—
—
Rt MCA
12 mm
Hematoma evacuation (4 h) and delayed clipping (day 4)
Residual mild left hemiparesis, returned to work as a teacher, GOS 4, mRS 3

O’Sullivan et al. [3]/1994
24
63/f
WFNS 5, GCS 3, dilated unreactive pupils
CT scan, DSA
Yes
—
Rt
—
—
Rt ICA-Pcom
20 mm
Hematoma evacuation (4 h) and delayed clipping (day 7)
Full recovery, returned to normal lifestyle, GOS 5, mRS 1

O’Sullivan et al. [3]/1994
25
62/f
WFNS 3, GCS 14, mild left hemiparesis
CT scan, DSA
Yes
No
Rt
20 mm
—
Rt ICA-Pcom
4 mm
Hematoma evacuation and immediate clipping
Uneventful recovery, returned to normal lifestyle, GOS 5, mRS 1

Nowak et al. [14]/1995
26
52/f
WFNS 5, GCS 3, dilated unreactive pupils, hypertensive crisis (systolic BP 280 mmHg)
CT scan
Yes
No
Rt
—
—
Rt Pcal (ACA)
—
Manitol, emergency hematoma evacuation
Deceased, GOS 1, mRS 6

Nowak et al. [14]/1995
27
45/f
WFNS 1, GCS 15, disturbances of vision
CT scan, DSA
Yes
Yes
Rt
10 mm
—
Rt MCA
—
Hematoma evacuation and clipping (day 1)
Full recovery, returned to normal lifestyle, GOS 5, mRS 1

Nowak et al. [14]/1995
28
49/f
WFNS 5, GCS 3, mild left-sided hemiparesis
CT scan
Yes
—
Rt
—
Marked
Rt MCA
>25 mm
Emergency hematoma evacuation with gluing of the aneurysm
Deceased, GOS 1, mRS 6 (rebleeding)

Nowak et al. [14]/1995
29
63/m
WFNS 5, GCS < 6, right dilated pupil
CT scan, DSA
Yes
—
Rt
—
—
Rt MCA
10 mm
Immediate hematoma evacuation and delayed clipping (week 5)
Full recovery, no serious neurological deficits, GOS 5, mRS 1

Ishibashi et al. [15]/1997
30
54/f
WFNS 1, GCS 15, no neurological deficit
CT scan, DSA
No
No
Lt
—
—
Lt ICA-PCom
—
Craniotomy, hematoma evacuation, and immediate clipping (<24 h)
No neurological deficit, return to normal life, GOS 5, mRS 1

Nonaka et al. [16]/2000
31
52/f
GCS 4, decerebrate rigidity, and left oculomotor paresis
CT scan, DSA
No
No
Lt
—
Moderate to marked
Lt ICA-PCom
10 mm
Craniotomy, hematoma evacuation, and immediate clipping (>24 h)
Full recovery, no neurological deficits, GOS 5, mRS 1

Inamasu et al. [17]/2002
32
68/m
WFNS 2, GCS 14, H&H II
CT scan, DSA
Yes
No
—
<25 cc
<5 mm
Acom
—
Craniotomy, hematoma evacuation, and immediate clipping (6 h)
Good recovery, GOS 5, mRs 1

Inamasu et al. [17]/2002
33
61/f
WFNS 4, GCS 10, H&H IV
CT scan, DSA
Yes
Yes
—
<25 cc
<5 mm
Rt MCA
—
Craniotomy, hematoma evacuation, and immediate clipping (6 h)
Good recovery, GOS 5, mRs 1

Inamasu et al. [17]/2002
34
75/f
WFNS 4, GCS 11, H&H IV
CT scan, DSA
Yes
Yes
—
<25 cc
<5 mm
Lt MCA
—
Craniotomy, hematoma evacuation, and immediate clipping (6 h)
Severe disability, GOS 3, mRS 5

Inamasu et al. [17]/2002
35
28/f
WFNS 5, GCS 5, H&H IV
CT scan,
No
No
Rt
<25 cc
>10 mm
Lt ICA-Pcom (autopsy)
—
Craniectomy and hematoma evacuation
Deceased (5 days after admission), GOS 1, mRS 6

Inamasu et al. [17]/2002
36
53/f
WFNS 5, GCS 4, H&H V, bilaterally dilated pupils
CT scan, DSA
Yes
No
Rt
<25 cc
>10 mm
Rt ICA-Pcom
—
Craniotomy, hematoma evacuation, and clipping
Deceased (3 days after admission due to severe postoperative brain swelling), GOS 1, mRS 6

Inamasu et al. [17]/2002
37
72/f
WFNS 5, GCS 4, H&H V
CT scan,
Yes
No
—
<25 cc
>10 mm
Lt ICA-Pcom (autopsy)
—
Infusions of manitol, burr hole
Deceased, GOS 1, mRS 6

Inamasu et al. [17]/2002
38
53/m
WFNS 5, GCS 5, H&H V
CT scan
Yes
No
—
<25 cc
>10 mm
Unknown
—
Infusions of manitol, burr hole
Deceased, GOS 1, mRS 6

Inamasu et al. [17]/2002
39
47/f
WFNS 5, GCS 4, H&H V
CT scan
Yes
No
—
<25 cc
>10 mm
Unknown
—
Infusions of manitol, burr hole
Deceased, GOS 1, mRS 6

Inamasu et al. [17]/2002
40
70/f
WFNS 5, GCS 4, H&H V
CT scan
Yes
Yes
—
<25 cc
>10 mm
Unknown
—
No response to manitol infusion, conservative treatment
Deceased, GOS 1, mRS 6

Inamasu et al. [17]/2002
41
81/f
WFNS 5, GCS 4, H&H V
CT scan
Yes
No
—
<25 cc
>10 mm
Unknown
—
No response to manitol infusion, conservative treatment
Deceased, GOS 1, mRS 6

Inamasu et al. [17]/2002
42
55/m
WFNS 5, GCS 3, H&H V
CT scan
Yes
No
—
<25 cc
>10 mm
Unknown
—
No response to manitol infusion, conservative treatment
Deceased, GOS 1, mRS 6

Inamasu et al. [17]/2002
43
49/m
WFNS 5, GCS 3, H&H V
CT scan
Yes
No
—
<25 cc
>10 mm
Unknown
—
No response to manitol infusion, conservative treatment
Deceased, GOS 1, mRS 6

Gelabert-Gonzalez et al. [18]/2004
44
68/f
WFNS 5, GCS 4, fixed pupils
CT scan, DSA
Yes
No
Lt
—
—
Lt ICA-Pcom
—
Hematoma evacuation and immediate clipping (4 h)
Mild right-sided hemiparesis, GOS 4, mRS 2

Gelabert-Gonzalez et al. [18]/2004
45
64/f
WFNS 4, GCS 9, dilation of the right pupil
CT scan, CTA
Yes
—
Rt
—
Marked
Lt ICA-Pcom
—
Hematoma evacuation and immediate clipping (28 h)
Full recovery, neurologically intact, GOS 5, mRS 1

Gelabert-Gonzalez et al. [18]/2004
46
41/f
WFNS 5, GCS 4, right oculomotor paresis
CT scan, DSA
Yes
Yes
Lt
—
Marked
Lt ICA-Pcom
—
Hematoma evacuation and immediate clipping (5 h)
Deceased, GOS 1, mRS 6

Gelabert-Gonzalez et al. [18]/2004
47
59/f
WFNS 5, GCS 6, bilaterally fixed pupils
CT scan, DSA
Yes
No
Rt
—
—
Rt ICA
3 mm
Hematoma evacuation and immediate clipping (9 h)
Deceased, GOS 1, mRS 6

Krishnaney et al. [19]/2004
48
42/f
WFNS 2, GCS 14
CT scan, MRI, MRA, DSA
No
No
Bilateral
—
—
Acom
10 mm
Craniotomy, hematoma evacuation and clipping, (6 days)
Uneventful recovery, no neurological deficits, GOS 5, mRS 1

Kim et al. [20]/2005
49
72/f
WFNS 2, GCS 14
CT scan, DSA
Yes
Yes
Rt
6 mm
8 mm
Lt distal ACA
—
Hematoma evacuation and immediate clipping (48 h)
Dysphasia, right hemiparesis, GOS 3, mRS 4

Kim et al. [20]/2005
50
42/m
WFNS 5, GCS 3, bilaterally fixed pupils
CT scan, DSA
Yes
—
Lt
6.5 mm
10 mm
Lt ICA-Pcom
—
Hematoma evacuation and immediate clipping (3 h)
Mild left-sided arm paresis, GOS 4 mRS 3

Marinelli et al. [21]/2005
51
62/f
WFNS 1, GCS 15, complete left third nerve palsy
CT scan, MRI, MRA, DSA
No
No
Lt
—
—
Lt ICA-Pcom
10 mm
Endovascular embolization
Full recovery of left third nerve palsy, GOS 5, mRS 1

Hori et al. [22]/2005
52
57/m
WFNS 2, GCS 13-14, incomplete right oculomotor palsy
CT scan, DSA
No
No
Rt
—
Moderate to marked
Rt MCA
1.5 mm
Hematoma evacuation and immediate clipping
Full recovery, GOS 5, mRS 1

Koerbel et al. [23]/2005
53
62/f
WFNS 4, GCS 10-11, rapid neurological deterioration
CT scan, DSA
No
No
Lt
—
Moderate to marked
Lt ICA-Pcom
5 mm
Hematoma evacuation followed by coiling
Returned to normal lifestyle, GOS 5, mRS 1

Westermaier et al. [4]/07
54
55/f
WFNS 5, GCS 6, anisocoria right
CT scan, DSA
Yes
Yes
Rt
—
—
Rt Acom
—
EVD coiling and hematoma evacuation (24 h)
No formal deficits, mobile for short distance, GOS 4, Barthel 70

Westermaier et al. [4]/07
55
56/f
WFNS 5, GCS 3, MI, bilaterally fixed pupils, cardiopulmonary unstable
CT scan, DSA
Yes
Yes
Rt
—
—
Rt MCA
Large
Repeated infusions of manitol, hematoma evacuation, and immediate clipping (24 h)
Simple communication, left hemiparesis, permanent care, GOS 3, Barthel 20

Westermaier et al. [4]/07
56
55/f
WFNS 5, GCS 3, dilation of the right pupil
CT scan, DSA
Yes
No
Rt
—
—
Rt ICA-Pcom
—
Immediate hematoma evacuation, EVD and delayed coiling (24 h)
Mild left hemiparesis, GOS 4, Barthel 70

Westermaier et al. [4]/07
57
55/f
WFNS 5, GCS < 6, anisocoria right
CT scan, DSA
Yes
No
Rt
—
—
Rt Acom
—
Immediate hematoma evacuation, EVD, and delayed coiling (24 h)
Full recovery, return to work, GOS 5, mRS 1

Westermaier et al. [4]/07
58
43/f
WFNS 5, bilaterally fixed and dilated pupils
CT scan
Yes
No
Lt
—
—
Lt ICA-Pcom
—
Hematoma evacuation followed by coiling
Rt hemiparesis using a wheelchair for longer distances, GOS 3, Barthel 70

Westermaier et al. [4]/07
59
54/f
WFNS 5, GCS 3, dilation of the right pupil, cardiac instability
CT scan, DSA
Yes
—
Rt
—
—
Rt Acom
—
EVD, delayed coiling (24 h), hematoma evacuation three weeks later (burr hole)
Not able to walk, dependent on permanent care, GOS 3, Barthel 0

Westermaier et al. [4]/07
60
42/f
WFNS 5, dilation of the right pupil
CT scan, DSA
Yes
—
Rt
—
—
Rt ICA-Pcom
—
EVD, hematoma evacuation, and immediate clipping
Returned to normal lifestyle, GOS 5, Barthel 100

Westermaier et al. [4]/07
61
55/f
WFNS 5, bilaterally fixed pupils, cyanotic and hypoxic
CT scan
Yes
Yes
Rt
5 mm
4 mm
Rt MCA
14 mm
No therapy as a result of prolonged hypoxia before admission
Deceased, GOS 1, mRS 6

Gilad et al. [24]/2007
62
47/m
WFNS 1, GCS 15, partial left sixth cranial nerve palsy
CT scan, MRI, MRA, DSA
No
No
Tentorium midline
—
—
Intrasellar Acom
13 mm
Coil embolization alone
Uneventful, no neurological deficits, GOS 5, mRS 1

Suhara et al. [25]/2008
63
27/f
WFNS 4, GCS 8
CT scan, DSA
No
No
Rt
—
—
Lt Pcal (ACA)
7 mm
Craniectomy, immediate hematoma evacuation, and delayed clipping (5 days)
Uneventful recovery, no neurological deficits, GOS 5, mRS 1

Nishikawa et al. [26]/2009
64
45/m
WFNS 5, GCS 5, dilated slowly reacting pupils
CT scan, MRI, MRA
No
Yes
Bilateral
—
Moderate to marked
Lt ICA
—
Emergency hematoma evacuation, and clipping
Deceased (cerebral herniation 6 days after admission), GOS 1, mRS 6

Kocak et al. [27]/09
65
68/f
WFNS 5, GCS 6
CT scan, DSA
Yes
No

—
—
Rt ICA bifurcation
—
Patient died during resuscitation
Deceased, GOS 1, mRS 6

Kocak et al. [27]/09
66
53/m
WFNS 2, GCS 14
CT scan, DSA
Yes
No

—
—
Lt Pcom
—
Craniotomy, hematoma evacuation, and immediate clipping
Good recovery, GOS 5, mRs 1

Kocak et al. [27]/09
67
48/f
WFNS 3, GCS 10
CT scan, DSA (after hematoma evacuation)
Yes
No

—
Moderate to marked
Rt Pcom
—
Craniotomy and immediate hematoma evacuation, delayed clipping (6 days)
Severe disability, GOS 3, mRS 5

Kocak et al. [27]/09
68
63/f
WFNS 1, GCS 15
CT scan, DSA
Yes
No

—
—
Lt MCA
—
Craniotomy, hematoma evacuation, and immediate clipping
Good recovery, GOS 5, mRs 1

Kocak et al. [27]/09
69
51/f
WFNS 2, GCS 14
CT scan, DSA
Yes
No

—
—
Acom
—
Craniotomy, SDH evacuation, clipping
Good recovery, GOS 5, mRs 1

Kocak et al. [27]/09
70
72/f
WFNS 4, GCS 8
CT scan, DSA
Yes
Yes

—
Moderate to marked
Rt MCA
—
Craniotomy, hematoma evacuation (aSDH + ICH) and immediate clipping
Deceased, GOS 1, mRS 6

Kocak et al. [27]/09
71
56/f
WFNS 4, GCS 7
CT scan, DSA
Yes
Yes

—
Moderate to marked
Rt MCA
—
Craniotomy, hematoma evacuation (aSDH + ICH), and immediate clipping (6 h)
Deceased, GOS 1, mRS 6

Kocak et al. [27]/09
72
67/m
WFNS 5, GCS 5
CT scan, DSA (after hematoma evacuation)
Yes
No

—
Moderate to marked
Rt Pcom
—
Craniotomy and immediate hematoma evacuation, delayed clipping (8 days)
Severe disability, GOS 3, mRS 5

Kocak et al. [27]/09
73
47/f
WFNS 1, GCS 15
CT scan, CTA, DSA
No
No

—
—
Acom
—
Craniotomy, hematoma evacuation, and immediate clipping
Good recovery, GOS 5, mRs 1

Kocak et al. [27]/09
74
57/f
WFNS 3, GCS 13
CT scan, CTA, DSA
Yes
No

—
—
Lt Pcom
—
Craniotomy, hematoma evacuation, and immediate clipping
Good recovery, GOS 5, mRs 1

Kocak et al. [27]/09
75
46/f
WFNS 4, GCS 12
CT scan, CTA, DSA
Yes
No

—
—
Rt Pcom
—
Craniotomy, hematoma evacuation, and immediate clipping
Severe disability, GOS 3, mRS 5

Marbacher et al. [2]/10
76
44/f
WFNS 5, GCS 3, bilaterally fixed pupils
CT scan, DSA
Yes
No
Rt
15 mm
10 mm
Rt Pcal (ACA)
5 mm
Craniectomy, hematoma evacuation (4 h), and delayed clipping
Full recovery, mild cognitive deficits, GOS 5, mRS 1

Marbacher et al. [2]/10
77
50/f
WFNS 3, GCS 13, mild left-sided hemiparesis
CT scan, CTA
Yes
Yes
Rt
9 mm
23 mm
Rt MCA
11 mm
Craniectomy, hematoma evacuation (12 h), and delayed coiling
Mild left-sided arm paresis, GOS 4, mRS 2

Marbacher et al. [2]/10
78
39/m
WFNS 5, GCS 4, bilaterally fixed pupils
CT scan, CTA
Yes
No
Rt
10 mm
14 mm
Rt ICA-Pcom
5 mm
EVD, craniectomy, hematoma evacuation, and immediate clipping (18 h)
Residual left-sided hemiparesis, GOS 4, mRS 2

Marbacher et al. [2]/10
79
58/f
WFNS 5, GCS 5, dilation of the right pupil
CT scan, CTA
Yes
Yes
Rt
5 mm
4 mm
Rt MCA
14 mm
Craniectomy, hematoma evacuation, and immediate clipping (3 h)
Full recovery, mild cognitive deficits, GOS 5, mRS 1

Marbacher et al. [2]/10
80
45/f
WFNS 5, GCS 4, dilation of the right pupil
CT scan, DSA
Yes
No
Rt
20 mm
18 mm
Rt ICA-Pcom
7 mm
Craniectomy, hematoma evacuation, and immediate clipping (2 h)
Gait ataxia, GOS 4, mRS 3

Marbacher et al. [2]/10
81
68/f
WFNS 1, GCS 15, right oculomotor paresis
CT scan, CTA
Yes
No
Rt
10 mm
6 mm
Rt Distal ICA-Pcom
2 mm
Craniotomy, hematoma evacuation, and immediate clipping (6 h)
Full recovery, no symptoms at all, GOS 5, mRS 0

Marbacher et al. [2]/10
82
27/f
WFNS 5, GCS 3, bilaterally fixed mydriasis, unstable cardiopulmonary condition
CT scan, DSA
Yes
No
Rt
10 mm
7 mm
Rt Pcal (ACA)
12 mm
Craniectomy, hematoma evacuation (1 h)
Deceased, GOS 1, mRS 6

*Summary (characteristics) of 82 cases from 20 clinical case series or case reports of aneurysmal acute subdural hematomas. Abbreviations: SAH = subarachnoid hemorrhage; ICH = intracerebral hemorrhage; aSDH = acute subdural hematoma; MLS = midline shift; mm = millimeter; f = female; m = male; WFNS = World Federation of Neurological Surgeons; GCS = Glasgow Coma Scale; CT = computed tomography; Rt = right; Lt = left; mRS = modified Rankin Score; GOS = Glasgow Outcome Scale; FU = followup; NOS = not otherwise specified; Barthel = Barthel Index; DSA = digital subtraction angiography; MRI = magnetic resonance imaging; MRA = magnetic resonance angiography; MCA = middle cerebral artery; CTA = CT angiography; ICA = internal carotid artery; Pcom = posterior communicating artery; Acom = anterior communicating artery; ACA = anterior cerebral artery; Pcal = pericallosal artery; EVD = external ventricular drainage; MI = myocardial infarction.

(a)

(b)

(c)

(d)

(e)

(f)

(g)

(h)

Figure 1: Data analysis of 82 cases of aneurysmal aSDH*. *Abbreviations: WFNS = World Federation of Neurological Surgeons; CT = computed tomography; DSA = digital subtraction angiography; CTA = CT angiography; MRA = Magnetic resonance angiography; mm = millimeter; Pcom = posterior communicating artery; MCA = middle cerebral artery; Acom = anterior communicating artery; Pcal = pericallosal artery; ICA = internal carotid artery; GOS = Glasgow Outcome Scale.

3.1. Initial Clinical Findings

Most of the patients were admitted with the worst initial clinical SAH grades and with signs of uncal herniation. The distribution according to the WFNS was grade 5 (, 57.3%), grade 4 (, 17.1%), grade 3 (, 7.3%), grade 2 (, 9.8%), and grade 1 (, 9.8%). At admission, signs of uncal herniation, major focal neurological deficits, and minor focal neurological deficits were present in 35 (42.7%), eight (9.8%), and six (7.3%) patients, respectively. Fourteen (17.1%) patients presented in an unstable cardiopulmonary condition (e.g., ventricular arrhythmia, acute heart failure, and sudden pulmonary edema) at the time of admission. Four (4.9%) patients died during resuscitation. One (1.2%) patient was reported to have had prolonged hypoxia.

3.2. Diagnostic Approaches and Radiological Findings

For all patients, the first radiological assessment was a CT scan (, 100%). 68 (82.9%) patients underwent additional DSA, and 11 (13.4%) underwent additional CTA (Figure 2). Four (4.9%) patients underwent MRA prior to surgery. SAH was detected on initial CT scan in 68 (82.9%) patients. There were 13 (15.9%) cases of pure aSDH without associated SAH. 28 (34.1%) patients presented with additional ICH. In 24 (29.3%) patients, the size of the aSDH was reported (mean ± SD: , range: 5–20 mm). A total of 30 (36.6%) patients were reported as presenting with midline shift associated with aSDH (mean ± SD: , range: 4–23 mm). All but six cases (7.3%) of aSDH were documented ipsilateral to the side of the aneurysm. Two cases presented with bilateral aSDH. Aneurysm size was reported in 37 (45.1%) patients (mean ± SD: , range: 1.5–30 mm).

(a)

(b)

(c)

(d)

Figure 2: Illustrative case: Panels (a–d) display axial CT scans with 3D reconstructions showing a right acute subdural hematoma with midline shift after rupture of a giant aneurysm located in the right middle cerebral artery. Panels (a) and (b): noncontrast-enhanced and contrast-enhanced axial CT scan, demonstrating a large aneurysm in the right silvian fissure with surrounding SAH, right-sided aSDH, and uncal herniation. Panel (c) shows a marked midline shift due to the mass effect of the aSDH. Panel (d) depicts the aneurysm with outgoing vessels.

3.3. Aneurysm Localization

In most of the cases, the aneurysm was located in the posterior communicating artery (Pcom) (, 46.6%). The rest of the aneurysms were located in the middle cerebral artery (MCA) (, 23.2%), the anterior communicating artery (Acom) (, 13.4%), the pericallosal artery (Pcal) (, 9.8%), or the internal carotid artery ICA (, 4.9%).

3.4. Treatment Strategies

The treatment strategies included urgent hematoma evacuation (, 72%), surgical aneurysm obliteration in the same procedure as urgent hematoma evacuation (, 50%), delayed clipping (, 12.2%), and delayed coiling (, 7.3%). Eighteen patients (22%) died during resuscitation or did not meet the criteria for undergoing any of the invasive procedures due to cardiopulmonary instability. A total of six (7.3%) patients underwent external ventricular drainage, and ten (12.2%) patients were treated with hyperosmolar therapy.

3.5. Outcome

Half of the patients were reported to have favorable outcomes (GOS 5 and GOS 4, , 47.6%). Poor outcome (GOS 3 and GOS 2) was reported in nine (11%) patients. 32 patients (26.6%) had fatal outcomes (GOS 1). Overall distribution according to the GOS was GOS 5 (, 37.8%), GOS 4 (, 9.8%), GOS 3 (, 9.8%), GOS 2 (, 1.2%), and GOS 1 (, 39%). In 19 (23.2%) out of 32 patients with fatal outcome (GOS 1), the critical status at admission did not allow any surgical or endovascular intervention. Four (4.9%) patients died during resuscitation, two (2.4%) patients died immediately after diagnosis, and one (1.2%) patient received no further therapy as a result of prolonged hypoxia before admission. Most of the 63 patients who met the criteria for invasive treatment achieved good outcomes (GOS 5 and GOS 4, , 69.9%). The distribution of these patients by treatment outcome according to the GOS was GOS 5 (, 49.2%), GOS 4 (, 12.7%), GOS 3 (, 12.7%), GOS 2 (, 1.6%), and GOS 1 (, 20.6%). Patients who suffered aneurysmal aSDH without SAH demonstrated better outcomes (GOS 5, , 69.2%; GOS 1, , 38.5%) than patients who presented with aneurysmal aSDH and SAH (GOS 5, , 31.4%; GOS 4, , 11.4%; GOS 3, , 11.4%; GOS 2, , 1.4%; GOS 1, , 38.6%).

3.6. Outcome Stratified by Therapeutic Strategies (Table 3)

Table 3: Outcome stratified according to therapeutic strategies*.

Patients presenting with rapidly deteriorating neurological condition
Patients presenting without rapidly deteriorating neurological condition

Urgent intervention (<24 h)
Delayed intervention (>24 h)
Urgent intervention (<24 h)
Delayed intervention (>24 h)

Outcome
(%)
Outcome
(%)
Outcome
(%)
Outcome
(%)

GOS 5 + 4
23 (64%)
GOS 5 + 4
6 (25%)
GOS 5 + 4
10 (100%)
GOS 5 + 4
5 (100%)

GOS 3 + 2
5 (14%)
GOS 3 + 2
2 (8%)
GOS 3 + 2
0 (0%)
GOS 3 + 2
0 (0%)

GOS 1
8 (22%)
GOS 1
16 (67%)
GOS 1
0 (0%)
GOS 1
0 (0%)

*Abbreviations: GOS = Glasgow Outcome Scale.

All patients presenting in good clinical condition without rapid neurological deterioration () demonstrated good outcomes (GOS 5 and GOS 4). These outcomes were favorable irrespective of whether hematoma evacuation and aneurysm obliteration were immediate () or delayed (). However, patients with rapidly deteriorating levels of consciousness (including signs of brain herniation) and urgent (<24 h) intervention had a higher likelihood of good outcomes (GOS 5 and GOS 4) than patients with rapid deterioration who had undergone delayed (24 h) treatment (64% versus 25%).

4. Discussion

This meta-analysis of 82 reported cases presenting with aneurysmal aSDH and rapid neurological deterioration revealed that urgent surgical decompression and immediate occlusion of the aneurysm seem to be an acceptable treatment strategy in order to achieve better outcome (GOS 5 and GOS 4 = 64%). Good outcomes are found in patients maintaining stable neurological condition irrespective of whether intervention was immediate or delayed (GOS 5 = 100%). Patients with pure aSDH due to a ruptured aneurysm demonstrated better outcomes than patients who suffered aneurysmal aSDH associated with SAH. Patients in unstable cardiopulmonary condition, with unstable blood pressure and serious ventricular arrhythmias, have the highest risk of unfavorable outcomes. All patients who did not meet the criteria for invasive treatment had fatal outcomes.

Poor clinical presentation per se is not associated with worse outcome. However, the combination of marginal cardiac output and reduced cerebral perfusion and cerebral blood flow due to the mass effect [31] during the acute phase of SAH [32] is likely to result in poor final outcome. Patients presenting in such condition do not meet the criteria for urgent hematoma evacuation, which additionally worsens the likelihood of favorable outcome (GOS 5 and GOS 4 = 25%). Patients in stable hemodynamic condition are suitable for rapid surgical decompression and maximal medical treatment and have a higher chance of recovering in good neurological condition (GOS 5 and GOS 4 = 64%) despite severe SAH and poor initial GCS admission scores. Two-thirds of all patients with either poor grade SAH or traumatic aSDH usually do not survive, and functional outcome is rare [33–35]. The good recovery of patients with aneurysmal aSDH might be explained by the space-occupying effect of the hematoma, which mimics a worse clinical situation and does not reflect vital brain destruction.

Pure aSDH due to ruptured intracranial aneurysm is extremely rare. Only 20 cases have been reported so far, including 14 cases during the last two decades [16]. In most cases of aneurysmal aSDH, the history will distinguish a traumatic from a spontaneous cause [1]. However, the absence of hematomas and subarachnoid blood collections related to common aneurysm sites can impede the diagnosis. The finding that pure aneurysmal aSDH results in better outcome than aSDH with SAH may be explained by the fact that these patients less frequently have complications (delayed cerebral vasospasm and hydrocephalus).

Due to the rarity of the disease, no guidelines have been established. In most reports, patients have bad clinical features on admission, often presenting in a comatose state with pupillary abnormalities. Fast decision making is mandatory. Determining a differential diagnosis, as well as treatment modalities, can be complicated by the rapid clinical course and the mixture of symptoms due to the ruptured aneurysm or mass effect of the hematoma.

To address the lack of guidelines, we developed a flowchart for treatment of patients with aSDH. However, the evidence for the proposed treatment flowchart comes from case series and case reports with relatively small sample sizes. Therefore, the estimation of effects is imprecise, and clinical recommendations included in the management protocol are weak [36, 37].

In patients who are in good neurological condition at the time of admission, management may proceed in a standard manner (Figure 3, left side of the flowchart). After initial CT and CTA examination, DSA is the diagnostic modality of choice to verify the angioarchitecture of the aneurysm. If the aneurysm is suitable for endovascular obliteration and the aSDH remains clinically insignificant, the aneurysm can be occluded during the same procedure [4]. If a decision is made to occlude the aneurysm surgically, DSA provides relevant anatomical information and guidance in determining a clipping strategy and surgical approach.

Figure 3: Illustrative schematic diagram of the protocol (management algorithm) for diagnosis and treatment of aneurysmal acute subdural hematoma. CT = computed tomography. CTA = CT angiography. DSA = digital subtraction angiography. * = if available.

For the management of patients who are in a coma or whose level of consciousness is deteriorating rapidly, the choice of initial diagnostics is more demanding, and management decisions become difficult (Figure 3, right side of the flowchart). The aSDH may be the major determinant of neurological grade, and prompt hematoma evacuation may be life saving. At the minimum, neuroradiological investigations should consist of an emergency CT and CTA to visualize potential bleeding sources. Emergency treatment modalities such as maximal sedation, osmotherapy, and external ventricular drainage to reverse signs of brain herniation should be performed as quickly as possible. In these cases, the emergency situation forces the neurosurgeon to postpone DSA.

Intraoperative DSA would allow safe and complete aneurysm occlusion to be carried out at the same time as urgent hematoma evacuation [38, 39]. Patients would be spared a second procedure. However, Westermaier et al. [4] recently presented four patients who underwent separate delayed endovascular coiling after decompression and hematoma evacuation. Despite good neurological recovery in three of these four patients, subjecting patients to two separate procedures rather than clipping at the same time as hematoma removal remains controversial. Patients who present in unstable cardiopulmonary conditions cannot be operated on immediately. It seems that this subgroup of patients is exceptionally at risk of poor outcome. Withholding aggressive therapy in poor-grade patients in order to prevent vegetative survival is highly controversial and cannot be recommended.

5. Conclusion

Due to the rarity of aneurysmal aSDH, it remains difficult to define a comprehensive management protocol. In patients with poor neurological grade at admission and rapidly deteriorating levels of consciousness, urgent surgical decompression and immediate aneurysm obliteration result in favorable outcome (GOS 5 and GOS 4; 64%). Delay of immediate treatment in patients with rapidly deteriorating neurological conditions decreases the likelihood of a favorable outcome (GOS 5 and GOS 4; 25%). Good outcomes are observed in patients maintaining stable neurological condition irrespective of whether the intervention was immediate or delayed (GOS 5; 100%). Overall outcome of patients who suffered aneurysmal aSDH without SAH proved to be better (GOS 5, 69.2%) than the outcome of patients who presented with aneurysmal aSDH and SAH (GOS 5; 31.4%).

Conflict of Interests

The authors are solely responsible for the design and conduct of the presented study and report no conflict of interests. No funds were or will be received for this study.

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