1. Dr. C. Gambacciani IPOTENSIONE LIQUORALE: ASPETTI NEUROCHIRURGICI
UOC Neurochirurgia Aziendale
Azienda USL Toscana Nord-Ovest
Ospedale di Livorno

2. INTRODUCTION
spontaneous intracranial hypotension (SIH) is a condition resulting from cerebrospinal fluid (CSF) HYPOVOLEMIA;
this hypovolemia is non-iatrogenic (not secondary to a lumbar puncture or surgery) and typically occurs due to a CSF leak;
SIH is potentially curable if the leackage can be arrested.
Epidemiology
5/ M:F=1:1,5

3. KEY-POINTS
Low CSF opening pressure was once throught to be the defining characteristic of this condition, but nowadays is evident that CSF pressure is NORMAL in the majority of the patients.
As CSF volume falls due to the fixed intracranial space, this loss must be ‘‘compensated” by concomitant increase in the volume of low resistance structures such as cerebral and peri-pituitary veins and major, dural sinuses, according to the Monro-Kelly doctrine.
The decrease of intracranial volume is caused by a leackage from the spine; infact, a skull base fracture do not produce SIH
CSF pressure: <6 cmH2O : low
6-15 cm H20 normal
>15 cm H2O : high

4. DIAGNOSIS CLINICAL FEATURES
Orthostatic headache (relieved quickly upon lying down)
Symptoms related to cranial nerve disfunction
-diplopia;
-hearing loss;
-tinnitus;
-disequilibrium

5. DIAGNOSIS RADIOLOGICAL FEATURES
Engorgemet of dural sinuses (venous distension signs)
Flattening of the ponts against the clivus with obliteration of pre-pontine cistern
Diffuse dural pachimengial enhancement;
Flattenig of corpus callosum
Subdural hematoma

6. IMAGING MADALITIES AND TECHNIQUES
MRI
Computed tomographic myelography (injection of mielographic contrast material into the subarachnoid space)
Dinamic myelography with or without digital subtraction (tilt table in conjunction with rapid image capture )
MR mielography with intratecal gadolinium

7. CLASSIFICATION OF SPONTANEOUS SPINAL CSF LEAKS

8. Ostheofite that pierces the dura and arachnoid;
SURGICAL TREATMENT
Removal of ostheofite/calcified herniated disc
Dural repair
Ostheofite that pierces the dura and arachnoid;
-VENTRAL, usually due to a calcified herniated disc;
-DORSAL damage, due to a ligamentum flavum calcification and facet osteophytosis.

9. SPINAL PATHOLOGY and SIH
2016
REVIEW
20 cases
-4 patients: osteophyte
-11 patients: calcific disc herniation
-5 patients: osteophyte + calcific disc herniation
SUCCESSFUL TREATMENT
12 EBP
(single/multiple)
8 SURGERY
(6 after failure of EBP)

10. confirmed of water tight closure with Valvalsa
Diverticulum of a spinal nerve root sleeve; dural tear with exposure of more friable arachnoid
associated with connective tissue disease (Marfan syndrome, ADPKD);
more frequent in thoracic spine
SURGICAL TREATMENT
wide exposure of diverticulum and its drainage; (usually do not typically contain neural structure);
recognition and dissection of ostium and its ligature with suture, renforced with muscle, fat or sintetic dura;
confirmed of water tight closure with Valvalsa

11. CSF-venous fistola, acquired and aberrant pathologic connection between the subarachnoid space and an adjacent epidural vein that allows for unregolation rapid tranfer of CSF into the bloodstream
SURGICAL TREATMENT
Sacrifice of a non appendicular nerve root or venous communication obliteration. The latter would be the preferred option with appendicular nerve roots that cannot be sacrificed without resulting deficits.

12. CONSERVATIVE TREATMENT
Bed rest (0°) at least 2 months
Oral hydration
(3000 ml/day)
Caffeine

13. CONSERVATIVE TREATMENT
Successful rate: overview of literature
Author (year)
Patients %
Kong et al (2005) 13
37 % at 6 months
63% at 2 years
Chung (2005) 53
19%
Wu (2017)
178 8%
Li (2019) 40
95%
….prolonged bed rest, without certainty of a cure, is quite burdensome, and many patients will therefore pursue other therapies…

14. EPIDURAL BLOOD PATCH (EBP)
Represent the widely accepted primary methods for the treatment of CSF leaks;
Involves acquiring sterile autologous blood from patient’s intravenous line and inject it throught a needle in the epidural space in order to seal CSF leak;
Is possible to inject also sealant material, as FIBRIN GLUE in an effort to improved patching efficacy;

15. EPIDURAL BLOOD PATCH (EBP)
NON TARGETED
if CSF leaks is unknown
generically injected in the lumbar spine or at the thoraco-lumbar junction;
20-40 ml of authologous blood;
usually performed without imaging guidance
TARGETED
injected in the site of a known CSF leak;
5 ml of authologous blood;
usually performed with fluoroscopic or CT guidance throught an interlaminar/trasforaminal approach

16. SUBDURAL HEMATOMA in SIH
reported incidence: 16-57%, mostly bilateral;
can be managed by conservative means and EBP with resolution in 85–100%;
failure to improve, or worsened clinical outcome after surgery without
prior closure of the CSF leak;
a ragionable choise is represented by closure of CSF leak by EBP immediately prior to surgery, in patients where surgery is deemed necessary.

17. SIH: our experience Male, 37 year-old, orthostatic headache
Mobilization ?
Nov 2018
Dec 2018
Feb 19
Mar 2019
April 2019
BED REST AND HYDRATION

18. TAKE HOME MESSAGE
Although rare, SIH should be suspected in any patient reporting persistent headache with an orthostatic component.
Diagnostic testing are essential for both establishing diagnosiss and localizing spinal CSF leaks, in order to guide management.
EBP represent the first line of treatment.
Surgery can be effective in refractory cases.

19. THANK YOU FOR ATTENTION