- Cerebrovascular Disease: Neurosurgical procedures may be
required for conditions that are broadly referred to as "STROKE".
The term, "Stroke", actually encompasses any "vascular accident"
that affects the Central Nervous System (CNS). Common "Stroke" problems
occur as a result of:
- Obstruction of the blood supply to the Brain.
These are classified as "Ischemic Strokes" which may result in a
temporary neurological disorder such as Transient Ischemic
Attack (TIA- a neurological deficit lasting less than 24 hours)
or a Progressive Reversible Neurological Deficit
(PRIND- neurological deficits that are more serious but
will have reversed by 72 hours). In less fortunate
circumstances the neurological deficits are permanent or "fixed".
- Hemorrhage related to
Hypertensive Intracerebral Hemorrhage (bleeding in the Brain related
to abnormally high blood pressure), and
Arteriovenous Malformations (AVM),
Surgical repair or reconstruction of the major blood vessels that
supply blood to the Brain (intra and extra-cranial arteries) may be
required in order to prevent a stroke in some individuals.
In these cases the Extracranial blood vessels (Carotid and/or
Vertebral Arteries) may have significant focal narrowing (stenosis)
or ulcerating atherosclerotic "plaques" which can be
corrected either by direct surgical repair or with an
Interventional Neuroradiological Procedure (also called
"Endovascular") using an "Intraluminal Stent"
(similar to that used for Coronary Arteries). In other circumstances
reconstruction of the blood supply to the Brain may be
appropriate either by creating an entirely "new" vessel using a
"bypass" technique (commonly referred to as Extracranial-Intracranial
Bypass Graft (or EC-IC- as illustrated in Figures 1A & B) or
more rarely by directly removing a focal stenosis from within an
intracranial vessel ( a procedure called "endarterectomy".)
Figure 1A: Right Carotid Angiogram (Antero-posterior View)
Extracranial-Intracranial (EC-IC) Bypass Graft. The "new" (Lower Arrow)
vessel supplies both the Right & Left Cerebral Hemispheres. The "upper
Arrow" indicates the anastomosis point to the Intracranial (Supraclinoid
portion) Internal Carotid Artery.|
Figure 1B: Right Carotid angiogram-same patient demonstrating the "new"
Internal Carotid Artery Bypass graft (Lower Arrow). The Upper Arrow
indicates the anastomosis.
The incidence of Subarachnoid Hemorrhage (bleeding covering the
surface of the brain) is 10 per 100,000 persons per year. The
most frequent cause of spontaneous Subarachnoid Hemorrhage is
rupture of an Intracranial Aneurysm. The symptoms of
Subarachnoid Hemorrhage are characterized by a sudden onset of
severe headache that worsens over time, and includes nausea,
loss of consciousness (with or without seizure) and vomiting.
Depending on the extent of the bleed, symptoms of Subarachnoid Hemorrhage
can also include visual sensitivity to light (photophobia), a stiff
neck, and low grade fever. Symptoms before rupture of the Aneurysm occur
in 40% of persons and are usually due to minor subarachnoid
hemorrhage. These symptoms can also include headache or dizziness, and
tend to go unnoticed. Sudden onset of double vision may occur as an
aneurysm expands and injures a nerve inside the skull that controls
Cerebral Angiogram (Lateral View)
A Giant Internal Carotid Artery Aneurysm
Due to its size and location, the symptoms and neurological signs
can include visual impairment and/or double vision and epilepsy.
Approximately 30% of Subarachnoid Hemorrhages occur during sleep.
Smoking is a major factor in increasing the odds of sustaining a
Subarachnoid Hemorrhage. After a Subarachnoid Hemorrhage, most patients are
hypertensive and experience changes in cardiac rate and
rhythm. CT scans are the best initial diagnostic tool for evaluating
patients suspected of having suffered a Subarachnoid Hemorrhage. CT scans
can be positive in 90% of patients within the first 24 hours and in more
than 50% in the first week after the hemorrhage has occurred.
Spinal taps to sample the Cerebrospinal Fluid (CSF) may be
required to evaluate some patients who are suspected of having had a
A spontaneous, Intracerebral (ICH) Hemorrhage is
a blood clot within the substance of the Brain tissue that usually
occurs abruptly. It is strongly correlated with hypertension.
There are approximately 40,000 new cases in the United States annually.
Stroke is the third leading cause of death in the United States,
and ICH accounts for 10% of all stroke cases. Advancing age is a
major predisposing factor for ICH: The incidence of
ICH is two per 1,000 persons per year by age 45 and 350 per 100,000
persons per year for those aged 80 years or more. Hypertensive
Intracerebral Hemorrhage can occur in different areas within the Brain
with damage to some areas being associated with a very high death rate.
- Tumors of the Nervous System: There are disease
processes which, if left untreated, can threaten the Brain, its
ability to function and life itself. These conditions include mass
lesions such as Brain Tumors and Brain Abscess which
exert undue pressure on the Brain causing damage as the pressure
inside the skull rises.
Tumors that affect the Central Nervous System (CNS-Brain
& Spinal Cord) include
and Malignant varieties;
Primary Tumors (those which arise from Brain or Spinal Cord
cells); Secondary or Metastatic Tumors (those cancers
which spread from some other region to the Brain and/or
Spinal Cord); Tumors of the Skull and/or
Spine (Primary or
Secondary Tumors involving the Bone that surrounds and protects the
CNS); Tumors of the Peripheral Nervous System (nerves
that lie outside the Brain and Spinal Cord which course throughout
the body); and tumors of the Autonomic Nervous System
(nerves that help control basic bodily functions).
The incidence of Primary Intracranial Tumors is 11.5 per
100,000 accounting for approximately 35,000 persons
per year in the USA. One of the most common types of tumors
accounts for 50% of all Primary Brain Tumors.
Approximately 250,000 persons in the USA are affected by
secondary (also called Metastatic) intracranial
tumors each year.
Figure 4A (Left): MRI Scan (Transaxial View-Gadolinium Enhanced)|
Cystic Metastatic tumor within the Left Occipitoparietal lobe with
surrounding Brain swelling (edema) indicated by the "darker grey"
Figure 4B (Right): MRI Scan (Sagittal View (same patient). The
swelling (indicated by the "darker grey" (Arrow) adds considerable
"mass" effect beyond that of the Cystic tumor.
A tumor in the Brain can become apparent when there is an
increase in the pressure inside the skull (known as intracranial
pressure or ICP) or when the tumor grows and
compresses particular parts of the Brain. Slowly
growing Brain Tumors may not become apparent clinically for many
years since the Brain is compressible and may tolerate that
compression quite well. Once the Brain can no longer
tolerate any added mass, symptoms begin to appear.
Once this happens it is actually quite late in the course of this
disease process. Common symptoms associated with compression of
the Brain can include nausea, vomiting, headache that is worse
in the morning, blurred or double vision, drowsiness and a
reduced level of consciousness. Tumors causing focal
compression on or irritation of the Brain may cause seizures
(epilepsy) and/or result in impairment of some
neurological function (such as becoming weak in a
hand, arm foot or leg.) Other symptoms of progressive
loss of neurological function can manifest as diminished
hearing and ringing in the ears (tinnitus), difficulty with language
(aphasia) or balance problems (dysequilibrium).
Technical improvements combined with medical and anesthetic
advancements have made surgical removal of Brain tumors much safer
and more effective. Perhaps some of the most remarkable
examples have occurred in the treatment of
Skull Base Tumors.
There are some malignant tumors that are very sensitive to
chemotherapy or radiation therapy such as
In these cases, surgery may not be warranted.
- Degenerative Diseases of the Spine: Degenerative and
Herniated Disc disease,
(narrowing of the Spinal Canal) and instability of the Spinal Column
may cause compression and injury to the Spinal Cord and/or spinal
nerves resulting in neurological deficits and pain.
All of these are treated by Neurological Surgeons. We invite
the READER to consult an important document on this website:
Why Choose a Neurosurgeon for Spine Care?
Degenerative disorders of the spine are a common problem.
Between 50% and 90% of the population will experience back
pain at some point in their lifetime. Most of these back pain
symptoms subside on their own within a few weeks. However, the cost
to our society in decreased productivity and lost wages constitutes
a significant public health problem. Lower back pain (in the lumbar
spine) is one of the most common reason adults seek medical attention
and is among the most frequent reasons for referral to a Neurosurgeon.
The lumbar spine, in particular, withstands a considerable load as
it supports the weight of the entire Spinal Column.
Figure 5A (Left): X-ray of Lumbar Spine. Advanced Degenerative
arthritis with scoliosis|
Figure 5B (Center): Post-myelographic CT Scan (Sagittal Reconstruction)
demonstrating the advanced degenerative changes at the L3,4 disc space.
The Spinal Stenosis (narrowing of the Spinal Canal) at L3,4 & L4,5
results from hypertrophy of the posteriorly located Ligamentum Flavum
Figure 5C (Right): Post-myelographic CT Scan at the L3,4 level. The
Stenosis results from a cystic degeneration in Hypertrophic Ligamentum
The discs that lie between the vertebral bones act as shock absorbers.
Cervical (neck) and Lumbar (lower back) discs are very prone to
herniation and drying out (desiccation) as a result of the
load they bear and the motion to which they are subjected. Degeneration
of the discs may change bony structures in a way that results in
the formation of bone spurs (osteophytes) which then
causes nerve compression as those nerves leave the
spinal canal. Typically, individuals with degenerative disorders
of the spine experience pain, numbness, tingling (paresthesia), weakness
in an extremity and restriction of movement of the Lumbar or
- Congenital Abnormalities: Failures during Embryonic
development can result in the
abnormal formation of the Brain,
Spinal Cord and Spinal Column
either alone or in combination. Important changes in growth and
chemistry occur during the second week of gestation of the human
embryo which contributes to the development of the nervous system.
Several different types of cells proliferate as they move
together or separate into other structures according to an orchestrated,
natural time clock. Errors that result in Developmental Defects can
occur at different stages of embryonic development. These
conditions may be severe and obvious at or before birth, or quite
subtle and not manifest themselves until later in life.
Figure 6A: MRI Scan (Sagittal View). Arnold Chiari Malformation. The
Cerebellar Tonsils (Lower Right Arrow) are "herniated" below the
Cerebellar Hemispheres (Upper Arrow) through the Foramen Magnum
resulting in compression of the upper Cervical Spinal Cord and
Medulla (Left Arrow).|
Figure 6B: Operative Photo. Arnold Chiari Malformation. The Cerebellar
Tonsils (Lower Arrow) hang well below the Cerebellar Hemispheres
(Upper Arrow) resulting in compression of the Upper Cervical Spinal
Cord (Left Arrow).
- Pain: There are Nervous System Diseases that cause
severe and debilitating pain. Among these are
Trigeminal and Glossopharyngeal Neuralgias.
Pain conditions of this magnitude are often first treated with
medications such as anticonvulsant drugs. For many patients this may
require life-long drug therapy. Oftentimes the medication either fails
to continue to be effective or creates disagreeable or intolerable
side effects. In these latter circumstances there are Neurosurgical
procedures that can be very effective in relieving these conditions.
Figure 7A (Left): Operative Photo. Left Trigeminal Neuralgia caused by
compression/distortion of the Trigeminal Nerve (Lower Arrow) at its
Nerve Root Entry Zone of the Brain Stem by an elongated atherosclerotic
Artery (Upper Arrows).|
Figure 7 B (Right): Operative Photo (Same patient). The elongated Artery
(Upper Arrow) has been transposed to an inoffensive position away from
the Trigeminal Nerve (Lower Right Arrow) and held in place by a permanent
Ivalon sponge (Lower Left Arrow).
There are many other pain conditions that may be
successfully managed by Neurosurgical procedures
among which a considerable number are related to
as outlined above in #3.
- Traumatic Head or Spine Injury: These are conditions
caused by accidents or assaults.
Accidents that result in head injury are a major public health problem.
Trauma causes approximately 150,000 deaths annually in the
United States; approximately half of these deaths are caused by
fatal head trauma. Additionally, there are 10,000 new
Spinal Cord injuries annually. The cost of disability (e.g.,
chronic long-term care, lost wages and work) is very high. Approximately
200,000 persons in the United States are living with disabilities
consequent to Head and Spinal Cord trauma.
Fractured spine conditions may require surgical
management either to stabilize the spine and/or relieve
pressure on the Spinal Cord or nerve roots.
- Spine Trauma: Injuries to the Cervical, Thoracic and/or
Lumbar Spine may result in injury to the Spinal Cord
and/or Nerve Roots or could be related ONLY TO THE
STRUCTURAL SUPPORT MECHANISM. In any of these cases,
Neurosurgical consultation is appropriate.
Figure 8A (Left): CT Scan (Sagittal "reconstruction") demonstrating
the Anterior dislocation of the C6 vertebral body on C7.|
Figure 8B (Center): Cervical Spine X-ray (Lateral View) Arrows indicate
the misalignment of the Cervical Spine at C67 in the same patient.
Figure 8C (Right): CT Scan (Transaxial View-same patient) The right Facet
has been extensively fractured (Lower Arrow). The Right Foramen is
compromised by a bone fragment from the fracture of the Uncovertebral
Joint (Upper Arrow).
- Head Trauma: Severe head injury is defined as an injury
that produces coma.
These patients will not open their eyes even to painful stimulus, are
incapable of following simple commands and are unable to speak. These
clinical criteria are defined within a system known as the
Glasgow Coma Scale (GCS). A neurological assessment by
a trained physician and Brain scan imaging (CT scan) is necessary for
the initial evaluation. Neurosurgeons are often involved in the management
of these patients either directly or as consultants. There are times
when surgical intervention is required such as when the skull bones have
been fractured and driven into the brain (a depressed skull
fracture), when there is a large blood clot
that can cause progressive Brain injury or when a special catheter
to monitor intracranial pressure (due to Brain swelling) is
Figure 9A (Left): MRI Scan (Antero-posterior View)
Figure 9B (Right): MRI Scan (Transaxial View)
A large Right-sided Subdural Hematoma (Arrows) has caused considerable
"shift" of the midline Brain structures.
- Functional and Stereotactic Neurosurgery: This special
interest area involves the surgical treatments for
Movement Disorders (such as occurs with Parkinsonism); Epilepsy;
some Pain conditions; and Radiosurgery (the special field of
radiation therapy using stereotactic radiation equipment.)
Stereotactic Neurosurgery makes use of a coordinate
system that provides accurate "navigation" to a specific point or
region in the Brain. There are two main types of these systems.
One involves placing a frame onto the head (using four threaded
pins that penetrate the outer skull to stabilize the frame in
position) under local anesthesia. Once the frame is in
position, a special box and stereotactic arc are placed to precisely
determine X, Y, and Z coordinates of any point within the frame.
The other technique, called "Frameless Stereotactic Surgery",
uses different technology that is based upon concepts similar to a
"Global Positioning System", except in this case the
systems are either optically or magnetically based
rather than using "satellites in the sky".
Figure 10A (Left): Operating Room Photo. Minimally Invasive Endoscopic
Resection of a Skull Base Tumor using Image Guidance. The "Reference"
source for the Guidance positioning system is fixed in place (Arrow)
as is the patient's skull.|
Figure 10B (Right): Image Guidance Monitor. The surgical instrument's "tip"
and its location within the Skull (relative to the LOCATION OF THE TUMOR)
is indicated by the "cross hairs" on each of the 3-dimensional views. The
operative view is relayed from a miniature camera attached to the
endoscope (Bottom right).
Epilepsy (seizures) is a serious health problem for which
approximately 70 per 100,000 people in the United States take
antiepileptic medications. The risk of developing epilepsy
over a lifetime is 3%, and there are
100,000 new cases per year. The majority of cases (approximately
60,000) involve the Temporal Lobe portion of the Brain. Approximately
25% of patients prescribed antiepileptic drugs for Temporal Lobe
seizures are not adequately controlled or the side effects of the drug are
far too great and outweigh the therapeutic benefits. It is estimated
that 5,000 new cases of epilepsy per year require epilepsy surgery.
In the case of Temporal Lobe Epilepsy this consists of removing the front
part of the Temporal Lobe (a Partial Anterior Temporal Lobectomy.)
Surgery may be appropriate if frequent seizures cause injuries due to
repeated falls; driving restrictions; limitation of social interactions;
problems related to education and learning; and employment limitations.
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This page last edited on 2/22