DIAGNOSTIC IMAGING, MOLECOLAR IMAGING, INTERVENTIONAL RADIOLOGY AND RADIATION THERAPY

University Hospital “Tor Vergata” RomeChairman Prof. Giovanni Simonetti

Hydrodiscectomy

Assoc. Prof. of Diagnostic Imaging And Interventional Radiology Dept. Of Radiology Medical University of Rome Tor Vergata

Salvatore Masala

HydrodiscectomyDiscectomy through saline fluid jet with hig

velocity (900km/h).

The core technique involved in hydrodiscectomy is the targeted cutting and vacuuming of the nucleus pulposus

Components

The power console pressurizessterile water (pressure is user-controlled from approximately 84 to 1054 Kg/cm2) that is supplied from a standard 3L irrigant supply bag.

The pressurized water exits the distal tip of the hand-piece as a high-velocity jet, which crosses a short gap

Tissue directed into the gap is excised and drawn into the evacuation tube along with the water jet (Venturi effect)

Indications

-Intersomatic space larger than 4 mm

-Contained Disc Hernation

- Unsuccesful conservative pain treatment for at least 4 weeks

Exclusion criteria -Free floating disc fragment

-Osteophytic impingement on the nerve root

- Scar tissue entrapped nerve root due to previous surgery

- Spondylolisthesis

- Spinal stenosis

Approach

Introduction of the needle immediately anterior to the superior articular process and superior to the transverse process via a triangular safe zone

TechniqueLocal anestesia with a 22 G needle

Technique

Insertion of the spinal needle (17G)

Technique

10 G

Technique

Spine Jet Perc Resector

Our experience (1)18 patients with single level (9 pts) or multiple levels (9 pts) lumbar hernia were treated in our institution with

Spine Jet Hydrodiscectomy

VariablesAge (years, mean±DS) 49±13Male (no, %) 12(67)Level of operation L3-L4 /L4-L5 2 (11) L4-L5 / L5-S1 7 (39) L4-L5 6 (33) L5-S1 3 (17)

Our experience (2)In all patients preprocedural pain was evaluated through Oswerty score Index (OSI) the visual analogue scle (VAS), verbal rating

scale (VRS) and number rating scale (NRS)

VariablesPreprocedural Oswerty score Index (%, mean±DS) 53±25Preprocedural Visual Analogue Scale (mm, mean±DS) 73±19Preprocedural Verbal Rating Scale (Value) Very severe 8 (44) Severe 7 (39) Moderate 2 (11) Mild 1 (6)Preprocedural Number Rating Scale (no, mean±DS) 7-10 16 (89) 4-6 1 (8) 1-3 1 (8)

Our experience (3)Clinical follow-up was perfomed at 10 days and 6 months

6 patients were lost during FU

P<0,001 P<0,0013 patient had persistence of pain, of which 2 had a

multilevel L4-L5 and L5-S1 disease

State of art

Single center non randomized study 13 patients underwent hidrodiscetomy with soft disc herniation.Postoperative back and leg VAS scores were decreased to 3±1.4 (p<0.05) and 2.7±1.0 (p<0.05), respectively. Postoperative ODI score was decreased to 23±22.1% (p<0.05)

Single center non randomized study 13 patients underwent hidrodiscetomy with disc herniation.Evaluated using the modified MacNab method, the rate of excellent or good response was 56.5%, 82.6%, 88.4%, 98.6%, 98.6%, and 98.6% on day 15, 30, 90, 150, 210, and 270, respectively. In two cases outcomes were poor: - One with intervertebral distance<50% of normal and calcified degenerated portion of the disc- One complicated by disc space infection

Benefits of hydrodiscectomy

- No heat damage to intradiscal structures

- Ability to remove a precise, predictable amount of material from the disc regardless of the disc’s age or disc hydration

- Additional safety of retrograde, rather than forward, cutting action

- Small dilated annulotomy reduces risk of hernation

Predicatable amount of material removed

Connor B, DePasqua,A. Tissue consumption analysis using the SpineJet PercResector in acadaveric study. Data on file. HydroCision, Inc. 2003

Two cadavers were used to measure tissue consuption rates of nucleus removed with spine jet

Case40 yo male76% Oswerty score

Case

Case

Case

Too narrow for access cannula !

Limit of hydrodiscectomy

- It could not be used in narrow intervertabral space

- Risk of immediate postoperative pain for inflammation due to insertion of access cannula

ConclusionPercutaneous hydrodiscectomy can be a

new alternative procedurein lumbar disc decompression in

selected patients