This document discusses the history and application of neuronavigation in brain surgery. It begins with an overview of neuronavigation and its history from early localization techniques to modern frame-based and frameless navigation systems. Key aspects covered include the registration process, indications for various anatomical and functional applications like tumor resection and deep brain stimulation, and advantages like improved accuracy and safety. Challenges like brain shift and navigation errors are also reviewed along with recent advances integrating neuronavigation with intraoperative imaging and future prospects in robotics.

1. Application of Neuronavigation in
Brain Surgery
Dr Fakir Mohan Sahu
MBBS, MS, MCh SR Neurosurgery
AIIMS Bhubaneswar
10/10/2020

2. Learning Objectives
• What is Neuronavigation?
• Historical Prospects
• General Principle- Frame based & Frameless system
• Application-Anatomical & Functional
• Indication, Contraindication
• Advantage, Disadvantage
• Future Prospects

3. Neuronavigation
• Set of computer-assisted technologies used
by neurosurgeons
• To guide or "navigate” within the confines
of the skull or vertebral column during
surgery
• “Neuronavigator” - set of hardware for
these purposes

4. History of Navigation

5. Evolution of intraoperative Imaging modalities
• Radiography: Plain X-ray- Roentgen (1895)
• Ventriculography: Dandy (1918)
• Cerebral Angiography: Egas Moniz (1927)
• Ultrasonography: Ian Donald (1956)
• CT Scan: Hounsfield (1973)
• MR imaging : Paul C. Lauterbur (1973)
• PET/SPECT- Kuhl and Edwards (1963)
• IMAGE GUIDED NAVIGATION

6. Ventriculography: Dandy (1918)

7. Historical prospects
• Mechanical device for localization of intracranial structures- Zernov (1890)
Apparatus- Encephalometer, used external markers on the head
To calculate the position of intracranial targets.
• Brain navigation system - pioneers of stereotaxy.
‘Stereotaxic’ (Greek) for ‘three dimensional’ (stereo) and ‘system’ or
‘arrangement’ (taxis).
• In 1908 Horsley and Clarke - Frame based stereotactic method
- Each point in the brain was related to a rigid Cartesian coordinate system.
• The first Frameless stereotactic system; David Roberts and associates in 1986

8. Horsley and Clarke-1908

9. Frame based system

10. Initial days of target localisation

12. Neuronavigation Frameless System
Navigator system with
monitor and Localizer
Patient reference
frame and probe
Image data of the patient

13. General Principle
• Principle-to create virtual linkage between digital image data & real anatomical
structures.
• Technical features include three components:
First, the image generation system (CT-scanning or MR imaging) supplying the raw data.
Second, the pointer device
Third, the image processing system represented by a high capacity computer work station
for data storage and 3D-reconstruction.
• This procedure optically links the tip of the pointer, presented on the monitor
screen, and the displayed image dynamically
• Shows exact localization either in three perpendicular sectional 2D-views or in a
3D reconstructed image

14. Steps of Navigation

15. Steps of Neuronavigation system
• Obtaining preoperative image
(Sequential , Non-‐overlapping volumetric MRI/CT slices, 3D reconstruction)
• Registration (‘image dataset’ with the ‘real time surgical space’.)
Point or Surface alignment technique
Point technique : Fiducial or Anatomical landmark.
(e.g. nasion, external auditory canal, orbital margins)
Surface alignment: A Laser beam is used within sight of the optical digitizer to
delineate the periorbital and forehead regions of the scalp.

16. Fiducial
• Fiducia is Latin word meaning – TRUST
• Navigation is based upon targeting relative to
known reference points
• Bone fiducials like bone screws
• Skull implanted fiducials
• Adhesive markers
• Cranial markers

17. Steps of Neuronavigation system
• Dynamic Referencing
An optical reference frame with passive infrared reflectors is secured to the Mayfield head clamp.
 The optical digitizers recognize the fixed relationship between the reference frame and the
patient’s head.
• Intraoperative localization
• Intraoperative control
• Visualization and Surgery
• Post surgery evalution

18. Application of Neuronavigation
Anatomical applications
Tumour localisation (Small to skull base lesion )
Define the tumour margins and the limit of extension
Stereotactic Biopsy.
Craniotomy guided by stereotaxy.
Localizing encased and displaced vascular structures
Clipping of intracranial aneurysms.
Stereotactic Radiosurgery

19. Application of Neuronavigation
Intracranial Endoscopy(more precise planned trajectories )
Stereotactic third ventriculostomy,
Colloid cyst removals
Pituitary tumour using endoscopy
Intracranial Drainage
Cystic lesion
Abscesses guided by navigation
For local antibiotic therapy.
Introduction of catheter by navigation
Interstitial brachytherapy
Intracranial bleedings for evacuation and lysis therapy

20. Application of Neuronavigation
Functional: Surgery for movement disorders
– Parkinson’s disease.
– Hemiballismus.
– Dystonia.
– Choreoathetosis.
– Intention tremors.
– Intractable pain.
– Psychosurgery.
Placement electrodes
Electrode placement – Deep brain stimulation
Epilepsy—implantation of depth electrodes.

22. Localization of lesion

23. Stereotactic biopsy for deep seated tumour

24. STB (Stereotactic biopsy)
Indication of STB
• Multiple intracranial masses, (e.g. metastases, inflammatory lesions, lymphomas, multicentric gliomas.)
• Diffuse ill-defined intra-axial masses.
• Deep seated intra-axial lesions (thalamic/ hypothalmic gliomas, brainstem lesions)
• Lesions in eloquent locations, such as the motor or speech areas.
• Unresectable invasive lesions.
• Potentially radiosensitive lesions, such as germ cell tumours.
Contraindication
• Suspected vascular lesions.
• Large lesions with significant mass effect require an open craniotomy and decompression.
• Altered bleeding parameters.
• Extra-axial lesions, such as meningioma.
• Lesions close to the Sylvian fissure, suprasellar region and the third ventricle and most posterior fossa tumours.
Complication
• Haemorrhage.
• New neurological deficits.
• Seizures.
• Infection.

25. Localization of vascular lesion

26. Neuronavigation in a patient with 2 metastatic tumors (outlined in purple and pink), which were removed simultaneously in a single procedure.
Metastatic tumour

27. Neuronavigation in a patient with a colloid cyst. The colloid cyst is outlined in pink, the entry point is arked with a green cross, and the foramen of Monro with a red
cross. Parallel yellow lines represent the endoscope shaft.
Colloid Cyst

28. Neuronavigation - a chordoma engaging the clivus and C-1 and C-2 vertebrae. For better visualization of bone and soft tissues, MR images and CT data sets were fused preoperatively.
Clival Chordoma

29. Neuronavigation in a patient undergoing repeated operation for a pituitary adenoma. The tumor is outlined in yellow and the internal carotid arteries in pink. The red cross is the targeted anterior border
of the tumor, most remote of the carotid arteries.
Rec. Pituitary
Adenoma

30. Stereotactic Radiosurgery
• A single high dose of focused radiation can be
delivered to targets safely sparing normal tissue.
• Alternative to WBRT

31. Advantages
• Accurate, safe, Simple, cost effective
• Lowers the incidence of wound infection
• Shortens length of hospital stay
• Reduces the risk for neurological morbidity
• For Deep seated tumours, complete removal of tumours
• For saving surroundings brain and vital tissues

32. Disadvantage
• Neuronavigation errors
• Expensive
• Time consuming
• Delay in calculation, registration
• Brain shift
• Local tissue deformation

33. Neuro-‐navigation errors
Image dataset acquisition
• Overlapping or interspacing slices.
• Variable slice thickness due to mechanical factors
• Resolution errors and limitations
• Errors associated with image fusion algorithms
Prevention
• Careful planning on well maintained equipment

34. Registration error
• Adverse skin mobility
• Poor delineation of occipital region in surface mapping models
• Fiducial movement
Prevention
• Careful placement of Mayfield clamp
• Combination of surface and point registration
• Inclusion of the whole head during registration
• Intraoperative error
Parallax type error when planning craniotomy
• Head movement causing loss of registration
• Brain shift
• Small errors in trajectory angle are magnified at the tip of a biopsy needle

35. Brain Shift
 CSF drainage
 Use of diuretics
 Tumor resection which makes an error in the accuracy of the preoperative data.
(Deeper structures, such as those at the skull base or along the falx shift less than superficial structures)
• Prevention
 Displacement is often greatest in the direction of gravity
 Minimizing diuretic use
 CSF shunting should be avoided until after the primary approach has been made
 Defining the outer margins of a tumor before proceeding with debulking

36. Helen Brontë-Stewart, MD, MSE, Stephanie Louie, MS, Sara Batya, MD, Jaimie M
Henderson, MD,

39. Recent advances and Future prospects
Neuronavigation and Intraoperative MR Imaging (Brain Lab)
• The MRI functional, diffusion, and perfusion data would
constitute a virtual reality view of the brain
• Can make real-time, intraoperative MR imaging scans available.
• OT and all its instruments must be made MR imaging
compatible
Neuronavigation and Intraoperative SPECT and PET
• Both SPECT and PET imaging techniques require radionuclides
• Expenditures, and radiation hazards
• Introduction into the operating room is actually impossible
• Not cost-effective.

40. Recent advances and Future prospects
Neuronavigation and Intraoperative Ultrasonography
• Real-time imaging
• Without a radiation burden to the patient.
• Does not entail any special requirements on the neurosurgical armamentarium or the
environment OT.
• Cheaper than iCT and especially iMR imaging
• Providing the potential for brain shift evaluation and correction
• Intraoperative ultrasonography has its place in the neuronavigation of the future.
Neuronavigation and Robotics

44. Thank You