1. Angiogram-negative subarachnoid hemorrhage: is a repeat digital subtraction angiography necessary?
George Hadjigeorgiou
Department of Neurosurgery
Red Cross Hospital
Athens, Greece

2. Introduction 1100 patients with SAH/year in Greece
~15% of SAH have a negative initial DSA
Previous reports have estimated that a vascular origin of SAH could be identified in 2% to 24% of these cases on repeat DSA
DSA carries a neurological complication rate in the order of 2,6% and a 0,06% chance of death (Kaufmann,2008)

3. Is a repeat DSA necessary?

4. Material & Methods Retrospective analysis Single-center experience
Patients with SAH and a negative initial DSA were included in the study
Exclusion criteria: traumatic SAH

5. Material & Methods
All patients have underwent biplane DSA within 24 h of admission and a repeat angiography approximately 3-weeks after the initial study
MRI was also performed on attending neurosurgeon’s discretion during hospitalization
Clinical evaluation was based on the GCS and H&H grade at the time of admission, and functional outcome was assessed according to GOS
Hemorrhage patterns were categorized as perimesencephalic (PM) or nonperimesencephalic (NPM)

6. Material & Methods
PMC hemorrhage (Van Gijn’s definition, 1985): “a centre of hemorrhage located immediately anterior to the midbrain or within the prepontine cistern, with or without extension to the ambient cisterns; absence of complete filling of the anterior interhemispheric fissure; absence of extension of blood into the lateral sylvian fissure and into the ventricular system”
PM SAH
NPM SAH

7. Results 480 patients with SAH
Among them, 72 patients (15%) had a negative initial DSA
Mean age: 57.9 yo
39males : 33 females
42 PM-SAH : 30 NPM-SAH
Mean Age
57.9
Males
54.2%
Females
45.8%
PM-SAH
58,3%
NPM-SAH
41,7%

8. Results GCS PM (n:42) NPM (n:30) 15 22 12-14 20 11 9-11 3 3-8 13
3-8 1
H&H Grade
PM (n:42)
NPM (n:30) I 19 11 II 17 14
III 6 4 IV 1 V
Fisher
PM (n:42)
NPM (n:30) 1 2 4 3 38 16 12

9. Results
GOS
PM (n: 42)
NPM (n:30) 1 2 3 4 5 40 22

10. Results Repeat DSA 3 weeks after the initial
0/42 aneurysms for the PM-group
3/30 aneurysms for the NPM-group (1 Acom, 1 AChA, 1 BA)
Overall false negative rate of the initial DSA 3/72 (4.2%)

11. Illustrative Case Female, 54 yo
Medical History: G6PD def, thyroiditis Hashimoto
Sudden suboccipital headache, vomiting, nuchal rigidity
GCS 15/15, H& H II, Fisher III
DSA (24h upon admission): negative
CT on admission
DSA (24h)
CT on 4th day

12. Illustrative Case Rebleeding on the 14th day
2nd DSA : 3mm aneurysm of the right anterior choroidal a.  coiling
Discharge 1 week after the embolization on a GOS of 5
CT after the rebleeding
DSA prior the embolization
DSA after the embolization

13. Discussion
Reasons for missing the aneurysm on the initial negative DSA:
vasospasm
thrombosed aneurysm
very small aneurysm
suboptimal angiographic projection

14. Discussion
Clinical grades corresponding to GCS on admission and GOS at discharge were higher in PN group than the NPN group; however no statistical difference was shown
The majority of the patients in both groups had good clinical outcomes

15. Discussion
Need for evidence-based guidelines and a standardized protocol for the management of the DSA negative SAH
Conflicting findings from several studies
Study
Number of SAH pt
% of negative initial DSA
% of repeat DSA
% positive repeat DSA
In favour of repeat DSA
Gilbert (1990)
1086 2%
89% 0% No
Iwanaga (1990)
469
10%
84%
18%
Yes
Duong (1996)
295
31%
100% 5%
Urbach (1998)
694
55% 3%
Jung (2006)
3214 4%
72%
13%
Fontanella (2011)
882
12%
71% 9%
Yu (2012)
904
57%
Khan (2013)
459
11%
16%
Current Study
480
15%

16. Discussion Limitations of our study: Retrospective study
Small sample size
3-D reconstruction was not performed, thereafter some aneurysms could have been missed initially

17. Conclusions
In the line with the results of this study, we should be suspicious of patients with a non-perimesencephalic SAH and a negative initial DSA
We found no patient with perimesencephalic SAH and a negative initial DSA to conceal an aneurysm on the repeat DSA
Therefore, this may call into question the necessity of subsequent DSA in the PM-SAH group
Need for evidence-based guidelines

18. Thank you!