Neurosurgery Diagnostic Techniques

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What is a primary indication for using a CT scan in neurosurgery?

Assessment of venous sinus thrombosis

Diagnosis of acute neurosurgical lesions (correct)

Diagnosis of intracranial tumors

Evaluation of spinal surgery complications

Which condition is best assessed using an MRI rather than a CT scan?

Cerebral hemorrhage

Skull fractures

Brain tumors (correct)

Oedema due to trauma

What is a contraindication for performing an MRI?

Claustrophobia (correct)

History of brain tumors

Severe headaches

Incomplete recovery from anesthesia

Which imaging technique is preferred for diagnosing bone-related pathologies?

CT scan Signup and view all the answers

What is a primary purpose of diagnostic techniques in neurosurgery?

To screen, confirm diagnosis and aid in treatment planning Signup and view all the answers

How soon can infarction be diagnosed using an MRI compared to a CT scan?

MRI can diagnose infarction in few hours, CT in 48 hours Signup and view all the answers

Which of the following properties is essential for a diagnostic tool in neurosurgery?

It must be 100% sensitive and specific Signup and view all the answers

What is the primary purpose of a positron emission tomography (PET) scan?

Mapping tissue biochemistry and physiology Signup and view all the answers

Which condition is a contraindication for lumbar puncture?

Recent seizure Signup and view all the answers

Which condition would be diagnosed using a CT scan rather than an MRI?

Hydrocephalus Signup and view all the answers

What classification category does a magnetic resonance imaging (MRI) fall under?

Radiological Signup and view all the answers

Which investigation is most likely to show evidence of metastatic tumors?

Plain X-ray of the skull Signup and view all the answers

What is a common disadvantage of using MRI compared to CT scans?

MRI scans take longer to perform Signup and view all the answers

What is one indication for performing a lumbar puncture?

Suspected meningitis Signup and view all the answers

Which of the following is NOT a major abnormality to look for on a plain skull X-ray?

Presence of degenerative diseases Signup and view all the answers

What is typically NOT evaluated during the assessment of a plain X-ray of the spine?

Hematological abnormalities Signup and view all the answers

Which of the following is a key feature to check when analyzing plain X-rays of the spine?

Vertebral alignment and presence of lesions Signup and view all the answers

What is the purpose of a cerebrospinal fluid analysis within non-radiological investigations?

To identify infections and other abnormalities in the CSF Signup and view all the answers

What is a complication associated with lumbar puncture?

Post spinal headache Signup and view all the answers

Which diagnostic tool is most suitable for a study of carotid blood flow?

Ultrasound scan Signup and view all the answers

What is the purpose of measuring intracranial pressure?

Assessing brain health Signup and view all the answers

Which of the following is an advantage of ultrasound scanning?

Is faster and non-invasive Signup and view all the answers

Which tumor markers are typically associated with tumors in the pineal region?

Beta-HCG and Alpha fetoprotein Signup and view all the answers

What risk is increased in patients with a bleeding tendency who undergo lumbar puncture?

Epidural hematoma Signup and view all the answers

Study Notes

Introduction

Diagnostic techniques in neurosurgery have advanced with technological breakthroughs.
These tests are used to screen, confirm diagnoses, and assist in treatment planning.
Clinical acumen is still crucial.

Diagnosis

A combination of history, examination, and investigation is necessary for diagnosis.

Properties of a Diagnostic Tool

Easy to use
Non-harmful, non-carcinogenic, and non-allergic.
100% sensitive and 100% specific.
No ideal radiological tool exists.

Classification of Diagnostic Techniques

Radiological: Plain X-ray, ultrasound scan, computed tomography (CT) scan, magnetic resonance imaging (MRI), positron emission tomography (PET), radionuclide study.
Non-radiological: Cerebrospinal fluid analysis, hormonal assay, tumor markers, nerve conduction studies.

Plain X-Ray

Common investigation.
Useful for identifying fractures, dislocations, deformities, and infections.
Skull and spine X-rays are frequently requested.
Skull X-rays: AP and lateral views.
Spine X-rays: Cervical, thoracic, and lumbosacral spines.
Abnormalities to look for on skull X-ray include: linear or depressed fractures.

Computed Tomography (CT) Scan

Indications:
- Diagnosis of acute neurosurgical lesions in the head and spine, including skull and spinal fractures.
- Intracranial hemorrhage (extradural hematoma, subdural hematoma, intracerebral hematoma).
- Brain edema (due to trauma or other causes).
- Mass lesions, such as tumors and brain abscesses.
- Hydrocephalus.
- Stroke.
Advantages:
- Better than MRI for diagnosing bone-related pathologies like fractures and bone tumors.
- Better for acute hemorrhagic lesions.
- Faster than MRI (few minutes), making it suitable for critically ill patients.
Disadvantages:
- Uses ionizing radiation.

Magnetic Resonance Imaging (MRI)

Indications:
- Intracranial tumors.
- Cerebral abscess.
- Arteriovenous malformations.
- Venous sinus thrombosis.
- Craniospinal abnormalities, such as the Chiari malformation.
- Syringomyelia.
- Spinal tumors.
- Disc prolapse (cervical, lumbar, and dorsal).
- Spinal canal stenosis (lumbar or cervical stenosis) and cervical myelopathy.
Advantages:
- Superior to CT for sellar pathology (pituitary), posterior fossa tumors (cerebellar and brainstem tumors), and spinal cord pathology.
- Non-invasive myelography capability.
- Can diagnose infarction within a few hours.
- No ionizing radiation, allowing for safe repetition.
Disadvantages:
- Metallic foreign bodies in the body (plating and screwing, shells, cardiac pacemakers, intracranial clips) can interfere with MRI.
- Claustrophobia.
- Gross obesity.
- Uncontrolled movement disorders (Parkinson's disease).
- Respiratory disease requiring assisted ventilation or carrying risk of apnea.

Positron Emission Tomography (PET) Scan

Used to map tissue biochemistry and physiology (functional test).
Commonly used PET tracer is labeled glucose (Fludeoxyglucose (18F) (FDG).
Useful in differentiating ischemic from neoplastic areas.

Cranial and Spinal Angiography

Provides images of blood vessels.
Used to diagnose:
- Arteriovenous malformations.
- Intracranial aneurysms.

Ultrasound Scan (USS)

Transfontanelle USS:
- Detects hydrocephalus and intracranial bleeds.
Doppler Scan:
- Used for carotid studies.
Advantages:
- Simple, fast, and non-radiation based.
Disadvantages:
- Observer-dependent.

Non-Radiological Techniques

Cerebrospinal Fluid (CSF) Investigation

CSF can be obtained through spinal or cranial punctures.
Spinal puncture (lumbar puncture): Most safely accessed in the lumbar cistern, where the spinal cord ends in the cauda equina (between the first and second lumbar vertebrae).
Indications:
- Suspected meningitis.
- Subarachnoid hemorrhage (SAH).
- Cytology in neoplastic diseases.
- Measurement of intracranial pressure (ICP).
- Therapeutic CSF aspiration (pseudotumor cerebri).
- Conventional myelography via contrast injection.
- Spinal anesthesia.

Lumbar Puncture

Indications:
- Suspected meningitis.
- Subarachnoid hemorrhage (SAH).
- Cytology in neoplastic diseases.
- Measurement of intracranial pressure (ICP).
- Therapeutic CSF aspiration (pseudotumor cerebri).
- Conventional myelography via contrast injection.
- Spinal anesthesia.
Contraindications:
- Raised intracranial pressure (except pseudotumor cerebri).
- Features suggestive of raised ICP, including focal neurological deficit, recent seizure, papilloedema.
- Sepsis at the site of the LP.
- Bleeding tendency (coagulopathy and thrombocytopenia).
- Abnormal respiration.
- Vertebral deformities (kyphosis and scoliosis).
- Total spinal block.
- Obstructive hydrocephalus.
Complications:
- Post-spinal headache.
- Cerebellar tonsillar herniation (if there is raised ICP).
- Injury to neural structures.
- Back pain.
- Infection and meningitis.
- Implantation of cutaneous tissue, leading to an epidermoid cyst.
- Bleeding.
Measurement of intracranial pressure.

Hormonal Studies

Used to investigate sellar and parasellar pathologies (pituitary tumors, craniopharyngioma, tuberculum sellar meningioma).
Hormones measured:
- Prolactin.
- ACTH.
- Cortisol.
- TSH, T3, T4.
- GH.

Tumor Markers

Used in pineal region tumors.
Markers measured:
- Beta-HCG.
- Alpha fetoprotein.
- Placental alkaline phosphatase.

Conclusion

Diagnostic tests are essential for managing patients in neurosurgery.
A combination of history, examination, and investigation is crucial for reaching a diagnosis.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Description

Explore the advancements and classifications of diagnostic techniques in neurosurgery. This quiz covers various diagnostic tools, including radiological and non-radiological methods, their properties, and the importance of clinical acumen in diagnosis and treatment planning.