1. Hydrocephalus and Neuro Shunting
Sales Training
April 2001

2. Hydrocephalus: From the Greek
word hydro (water) & cephalo (head).
A pathological condition where there
is a disturbance in production,
circulation and/or absorption of CSF,
with subsequent accumulation of CSF
in the fluid-filled compartments of the
brain (ventricles).

3. About CSF (Cerebrospinal Fluid)
Clear, colorless fluid
Bathes, nourishes & protects brain and spinal cord.
Average CSF production-20ml/hr adults and 8ml/hr children
400 to 500cc produced daily contains 15 to 45mg/100ml protein,some glucose, salts, urea and WBC’s

4. Ventricular System 2 Lateral Third Fourth Foramen of Monro
Fluid filled cavities deep in cerebrum w/ pressure of mmH2O
Four ventricles
2 Lateral
Third
Fourth
Connected by
Foramen of Monro
Aqueduct of Sylvius

6. Choroid Plexus Very vascular Found throughout but mostly in lateral
Responsible for ICP waveform/
follows arterial pulse

7. Brain Layers/CSF Absorption
A. - Arachnoid
A.G. - Arachnoid
Granulation
B. - Bone
C.A. - Cerebral Artery
C.V. - Cerebral Vein
D. - Dura Mater
F.C. - Falx Cerebri
P.M. - Pia Mater
S. - Skin
S.A.S. - Sub-Arachnoid
Space
S.D.S. - Sub-Dural Space
S.S.S. - Superior Sagittal
Sinus

8. CSF Flow-path
CSF flows in a caudal direction through the lateral, third and fourth ventricles
Exits through foramina of Luschka and Magendie into subarachnoid space around spinal cord and brain.
Absorption occurs through the arachnoid granulations into the venous system.

9. Types of Hydrocephalus
Communicating
Non-communicating or Obstructive
Normal Pressure Hydrocephalus
Congenital
Acquired

10. CT Scan Showing severe
hydrocephalus
Normal CT Scan

11. Etiology of Hydrocephalus
Communicating
Overproduction/underabsorption of CSF
Choroid Plexus Papilloma-overproduces CSF
SAH
Infection
Neoplasms affecting the meninges
Trauma

12. Etiology of Hydrocephalus
Non-Communicating (Obstructive)
Aqueductal Stenosis
Arnold-Chiari Malformation (Cerebellar tonsils protrude into Foramen Magnum)
Cysts
Myelomeningocele
IVH
Tumors (particularly posterior fossa)

13. Normal Pressure Hydrocephalus
Usually present in elderly
Ventricular dilation despite normal CSF pressure
Triad of symptoms
1) dementia
2) gait disturbances (usually earliest)
3) urinary incontinence

14. Signs & Symptoms Associated with Hydrocephalus
Infants
Increased head size
Bulging Fontanels
Separation of Cranial Sutures
Prominent Scalp Veins
Persistent Vomiting
Lethargy or irritability
“Setting Sun” eyes
Seizures
Delayed Development

16. S/S Associated with Hydrocephalus, cont.
Toddlers
Increased head size
Persistent vomiting
Headache
Lethargy or irritability
“Setting Sun” eyes
Blurred Vision
Seizures
Delayed Development

17. Hydrocephalus
“SETTING SUN” EYES

18. S/S Associated with Hydrocephalus, cont.
Older Children & Adults
Persistent Vomiting
Headache**
Visual Problems
Lethargy
Behavior Changes
Difficulty with schoolwork
Seizures

19. Diagnosis Clinical Evaluation
Ultrasound (Intrauterine & through Fontanels.
CT Scan
MRI

20. Treatment Modalities Surgical Procedures
Remove obstruction (Blood Clots, Tumors)
Endoscopic Third Ventriculostomy
Septal Fenestrations (Endoscopic)
Cyst Fenestrations (Endoscopic)
Shunt Insertion

21. Interventions for Hydrocephalus
If untreated:
*50-60% die of complications
If treated:
*40% normal intelligence
*70% live beyond infancy

22. Questions???

23. Historical Treatment of Hydrocephalous
Hippocrates recognizes water accumulation in the brain.
1545-Thomas Phaire-1st non-surgical treatment--Herbal plasters, head wraps
18th Century--ventricular puncture--death from meningitis common
1800’s-Variety of materials used to “wick” CSF from ventricles to subarachnoid space (i.e., linen threads, glass wool, rubber tube)
1898-first lumboperitoneal shunt

24. Historical Treatment of Hydrocephalous, con’t
1922-Dandy-third ventriculostomy through subfrontal
approach
1923-Mixter-1st endoscopic 3rd Vent., choroid plexectomy
(L’Espinasse, Hildebrande, Dandy, Putnam and Scarff)
1950’s-First effective CSF diversion with a one-way valve
using biocompatible synthetic materials.
John Holter-1st Silicone Valve
Robert Pudenz-Silicone distal slit valve
Peritoneum chosen as better absorptive site than the
vascular system

25. Heyer Schulte and Shunt Industry History
1953: Dr. Robert Pudenz and W.T. (Ted) Heyer team up on hydrocephalus research
1955: Pudenz ventriculo-atrial shunt is developed
1959: Rudy Schulte joins Heyer and Pudenz
1959: Pudenz flushing valve is developed
1960: Codman distributes Heyer-Schulte products
1960: Holter valve is created
1965: Cordis begins U.S. presence
1965: Extra-Corporeal buys Holter
1973: Codman dropped as Heyer-Schulte distributor

26. Heyer Schulte and Shunt Industry History
1974: American Hospital Supply buys Heyer-Schulte
1975: Codman introduces their own product line
1977: Anasco, PR manufacturing facility is built
1978: Codman buys Extra-Corporeal
1983: AHS folds Heyer-Schulte into V. Mueller
1984: Dr. Pudenz and Rudy Schulte found P-S Medical
1986: Baxter-Travenol acquires AHS

27. Heyer Schulte and Shunt Industry History
The 90’s
NeuroCare Group acquires Heyer-Schulte
Radionics introduces full shunt line
Medtronic acquires P-S Medical
Phoenix Biomedical enters the market
Codman acquires Cordis
Elekta acquires Cordis
NMT acquires Cordis
Integra acquires Heyer-Schulte

28. What is a Shunt?
A shunt is a device that diverts CSF from the CNS (usually the lateral ventricle or the lumbar subarachnoid space) to an alternate body cavity (usually the peritoneum or the right atrium) where it is reabsorbed.

29. How Shunts Work
Divert CSF from the CNS to another body cavity (R atrium, peritoneum) for absorption.
Mechanical device that regulates flow out of the ventricle.
One-way valve opens when the sum of the forces acting on it exceed some threshold. (the difference between the inlet or ventricular pressure and outlet or peritoneal pressure.

30. Shunt Systems Ventriculo-peritoneal Ventriculo-atrial
Lumbar-peritoneal

32. Shunt Components Primary Components Optional Components Accessories
Proximal Catheter
Valve (Proximal or Distal)
Distal Catheter
Optional Components
Reservoir
Siphon Limiting Mechanism (ASD, SCD, GCD)
Accessories
Connectors
Guides
Introducers/Stylets
Catheter Passers

35. SHUNT ACCESSORIES Proximal catheter stylet (can use endoscope)
Stylets for unitized shunts
Shunt passers
Connectors and Right angle guides
Shunt tap kits
Manometers

41. Valve Mechanisms
Differential Pressure Valves
Flow regulating devices

42. Valve Mechanisms Differential Pressure Valves
Valves open when difference between the ventricular pressure and the peritoneal pressure exceeds some threshold.
Pressure difference at which a valve opens is called the opening pressure.
Pressure difference at which a valve closes is called the closing pressure.

43. Valve Types Burr Hole - shaped to fit the hole made in the skull.
The reservoir is an integral part e.g. Pudenz
Flat Bottom - rests flat against the skull distal to the
ventricular catheter e.g. LPV II, Novus
Cylindrical/In Line - appears “seamless” between the
ventricular and peritoneal catheters
e.g.. Ultra VS

45. Pudenz
Pudenz

46. Mishler Dual Chamber
Mishler Dual-Chamber

47. Ultra VS
Ultra VS Cylindrical

48. One Piece
One Piece Hydro Shunt

49. Ommaya Resevoirs
Ommaya

51. Internal Valve Components
Slit
Ball and Spring
Miter
Diaphragm

52. Valve Mechanisms
Slit
Miter

53. Valve Internal Mechanisms
High spring rate valves- open slowly, close quickly (miter, slit)
Low spring rate valves- open quickly, close slowly (diaphragm, ball & spring, prone to siphon)

54. Valve Mechanisms
Slit valves - a slit in a curved rubber layer. The flow arriving from the concave side opens slit, size of opening relating to the upstream pressure
Can be proximal or distal
Disadvantage:
”stickiness” of silicone rubber can affect opening
Precision?
Varies with age of valve?

55. Slit Valves Codman Radionics Phoenix Holter (proximal catheter/valve)
Denver (proximal catheter)
Accuflo (distal catheter)
Uni-shunt (distal catheter)
Radionics
Proximal slit valve
Phoenix
Holter-Hausner valve

56. One Piece
One Piece Hydro Shunt

58. Valve Mechanisms “stickiness” of silicone rubber can affect opening
Mitre valves - the leaves of the “duckbill” part in response to the pressure differential. Pressure characteristics of mitre valve are related to size,shape, thickness and length of leaves.
Disadvantage :
“stickiness” of silicone rubber can affect opening

59. Mitre Valves Heyer-Schulte Ultra-VS(cylindrical)
Mishler Dual Chamber (flat bottom)
Spetzler in-line Lumbar - Peritoneal valve (cylindrical)

61. Valve Mechanisms
Spring valves/Ball in cone - a metallic spring which applies force to a ball (usually ruby or sapphire) located in an orifice. Opening pressure is defined by spring stiffness
Disadvantage:
prone to obstruction from CSF debris or high protein content
subject to siphoning

62. Ball-in-Cone Valves Codman Medos Hakim NMT/Cordis Sophysa
Medos Programmable
NMT/Cordis
Atlas
Hakim
Orbis Sigma II
Sophysa
Sophy Programmable

64. Valve Mechanisms
Diaphragm valves - a round diaphragm rests on or under a valve seat. Pressure causes the diaphragm to be detracted from the seat allowing CSF to flow
Disadvantage:
prone to siphoning
in some designs flow is not laminar making it prone to obstruction

65. Diaphragm Valves Heyer-Schulte PS Medical/Medtronic Pudenz (burr hole)
LPV II (flat bottom)
Novus (flat bottom)
PS Medical/Medtronic
Delta (Burr hole, flat bottom)
Button(flat bottom)
Contour (flat bottom)

66. Diaphragm Valves Radionics Codman Contour Flex Equi-flow Burr hole
Accu-flo valve

68. Valve Mechanisms Flow regulating mechanisms
Maintains same flow rate at any differential pressure by increasing or lowering its resistance to pressure
May be achieved by a solid conical cylinder inserted inside a ring attached to a pressure sensitive membrane

69. Valve Mechanisms Inner diameter of ring is greater than larger
outer diameter of
conical cylinder
By reducing surface
area, mechanism
restricts amount of fluid
that can go through
Outer cylinder moves
to compensate for
reduced surface area
to maintain flow rate.

72. Valve Mechanisms At very low pressures acts like a DP valve
At high pressures the ring moves beyond the central cylinder to give a “blow off” valve.

73. Treatment for Siphoning
In a vertical position, negative pressure from hydrostatic column can cause overdrainage
Siphoning control achieved by adding siphon resistive devices to the shunt system.
Functions as a second valve in line that closes in response to peritoneal pressure

75. Shunt Failures and Complications
Shunt failure is at a maximum in first few months after surgery (25-40% at one year follow-up) Then falls to 4-5%
The mean survival for a shunt is approx 5 years

76. Shunt Failures and Complications
Shunt obstruction (about % of all failures)
Infection(between %)
Mechanical failure due to disconnection
Valve failure
Overdrainage
Patient/shunt mismatch

77. Shunt Placement Procedure
Skin Incision
Placement of Burr Hole
Sbcutaneous dissection
Tunnel the peritoneal catheter
Open dura & place ventricular catheter
Connect valve, test & clean
Distal catheter insertion & skin closure

78. Shunt Implantation Approaches
Occipital Approach
Temporal Approach
Frontal Approach

79. Metopic
Suture
Coronal
Suture
Anterior
Fontanelle
Sagittal
Suture
Posterior
Fontanelle
Lamboidal
Suture
Skull of a newborn seen from above
Adult human skull seen from above

80. Indications For Use of a Lumbar-Peritoneal Shunt
Communicating Hydrocephalus - when ventricles are small and it would be difficult to cannulate with a ventricular catheter.
Normal Pressure Hydrocephalus - shunting without necessitating a cranial procedure.

81. Goals of Shunt Design & Development
Restoration of “normal physiology” in the shunted individual
Maximize the potential quality of life for each patient
Expand the population of successfully treated patients

82. First Generation Diaphragm Valve

83. Second Generation Diaphragm Valve

84. Third Generation Diaphragm Valve

86. Integra NeuroSciences Consistency by Design

87. FLOW PATH
DELTA VALVE

92. at High Flow Rates (45.8ml/hr) LPV II Valve Performance
LPV Valve Performance
at High Flow Rates (45.8ml/hr)
LPV II Valve Performance
at High Flow Rates (45.8ml/hr)

93. at Low Flow Rates (4.6ml/hr) LPV II Valve Performance
LPV Valve Performance
at Low Flow Rates (4.6ml/hr)
LPV II Valve Performance
at Low Flow Rates (4.6ml/hr)

98. Silicon…….. Single Cavity pressure mold

99. Body… polysulfone…. Injection molding

100. Body and Housing made of Polysulfone

101. Cross linked silicone dome

102. All parts are glued together by technicians using Self Leveling RTV (room temperature vulcanizer)

103. Integral connectors made of nylon

104. Base made up of a Silicone “sandwich” with a Dacron center

105. Needle Guard is …polypropylene

106. Tantalum is added for radio opaque markings showing flow direction and pressures (L,M,H)

107. Competitive Matrix Medtronic P.S. Medical Cordis Codman Radionics
Sophysa
Phoenix

136. Flat Bottom Diaphragm Competitive Matrix

137. Flat Bottom Diaphragm Competitive Matrix

138. Burr Hole Diaphragm Competitive Matrix

139. Neonatal Valve Systems Competitive Matrix

140. Product line strengths
Consistency and predictability
Broad product line
Clnical support
History
Manufacturing expertise
Pricing flexibility