Talk to us?

Radiology NEET MDS Synopsis - Lecture Notes
Practice Subscribe 👤 Welcome User

📖 Radiology

Showing page 1 of 3 (12 total records)
Problems in Film Processing
Radiology

Common Problems in Film Processing

1. Light Radiographs

  • Causes:
    • Under Development:
      • Temperature too low
      • Time too short
      • Depleted developer solution
    • Under Exposure:
      • Insufficient milliamperage
      • Insufficient kVp
      • Insufficient exposure time
      • Film-source distance too great
      • Film packet reversed in the mouth

2. Dark Radiographs

  • Causes:
    • Over Development:
      • Temperature too high
      • Time too long
      • Accidental exposure to light
      • Improper safe lighting
      • Developer concentration too high
    • Over Exposure:
      • Excessive milliamperage
      • Excessive kVp
      • Excessive exposure time
      • Film-source distance too short

3. Insufficient Contrast

  • Causes:
    • Improper processing conditions (under or over development)
    • Depleted developer solution
    • Contaminated solutions

4. Film Fog

  • Causes:
    • Excessive kVp
    • Improper safe lighting
    • Light leaks in the darkroom
    • Contaminated developer solution

5. Dark Spots or Tines

  • Causes:
    • Contaminated solutions
    • Film contaminated with developer before processing
    • Film in contact with tank or another film during fixation

6. Light Spots

  • Causes:
    • Insufficient washing
    • Film contaminated with fixer before processing
    • Film in contact with tank or another film during development

7. Yellow or Brown Stains

  • Causes:
    • Insufficient washing after fixation
    • Depleted fixer solution
    • Contaminated solutions

8. Blurring

  • Causes:
    • Movement of the patient during exposure
    • Movement of the X-ray tube head
    • Double exposure
    • Misalignment of the X-ray tube head (cone cut)

9. Partial Images

  • Causes:
    • Top of film not immersed in developing solution
    • Film in contact with tank or another film during processing

10. Emulsion Peel

  • Causes:
    • Excessive bending of the film
    • Improper handling of the film

11. Static Discharge

  • Causes:
    • Static discharge to film before processing (results in dark lines with a tree-like image)

12. Fingerprint Contamination

  • Causes:
    • Fingerprint contamination during handling of the film

13. Excessive Roller Pressure

  • Causes:
    • Excessive roller pressure during processing can lead to artifacts on the film.
Vertical angulations for child patient
Radiology

General guidelines for vertical angulations for common dental radiographs in children:

Anterior Teeth

  1. Maxillary Central Incisors:
    • Vertical Angulation: +40 to +50 degrees
  2. Maxillary Lateral Incisors:
    • Vertical Angulation: +40 to +50 degrees
  3. Maxillary Canines:
    • Vertical Angulation: +45 to +55 degrees
  4. Mandibular Central Incisors:
    • Vertical Angulation: -10 to -20 degrees
  5. Mandibular Lateral Incisors:
    • Vertical Angulation: -10 to -20 degrees
  6. Mandibular Canines:
    • Vertical Angulation: -15 to -25 degrees

Posterior Teeth

  1. Maxillary Premolars:
    • Vertical Angulation: +30 to +40 degrees
  2. Maxillary Molars:
    • Vertical Angulation: +20 to +30 degrees
  3. Mandibular Premolars:
    • Vertical Angulation: -5 to -10 degrees
  4. Mandibular Molars:
    • Vertical Angulation: -5 to -10 degrees
Radiographic films used in Dentistry
Radiology

Radiographic films used in Dentistry

1. Intraoral Periapical (IOPA) Film

  • Size 0:
    • Dimensions: 22 x 35 mm
    • For: Small children
    • MPD (Maximum Permissible Dose) for whole body: 0.1 Rem in 1 year
  • Size 1:
    • MPD for gonads/bone marrow: 0.5 Rem in 1 year
  • Size 2:
    • Dimensions: 24 x 40 mm or 32 x 41 mm
    • For: Anterior projections and adults
    • MPD for gestation period in relation to the fetus: 5 Rem
    • MPD for skin: 0.5 Rem in 1 year
  • Radiation Exposure:
    • Mean exposure from one IOPA: 300 mR
    • Mean exposure from improved dental X-ray techniques: as low as 110 mR

2. Bitewing Film

  • Size 0:
    • For: Very small children
  • Size 1:
    • For: Children
  • Size 2:
    • For: Adults

3. Occlusal Film

  • Size:
    • 3 times larger than size 2 film (57 x 76 mm)
    • Used for capturing larger areas of the dental arch.

4. Screen Film

  • Size:
    • 8 x 10 inches
    • Used for extraoral projections in conjunction with an intensifying screen.

Additional Information

  • Erythema Dose: The amount of radiation necessary to produce a noticeable skin reaction, typically 300-400 R.
  • ALARA Principle: Stands for "As Low As Reasonably Achievable," emphasizing the importance of minimizing radiation exposure.
Structures and best view X ray
Radiology

Fractures of the Zygomatic Arch

  • Structures: Zygomatic arch, zygomatic bone.
  • Best Views:
    • Submento-Vertex View: Provides a clear view of the zygomatic arch and helps assess fractures.
    • Waters View: Useful for visualizing the zygomatic bone and maxillary sinus.
    • Reverse Townes View: Can also be used to visualize the zygomatic arch.

Base of Skull

  • Structures: Base of the skull, cranial fossae.
  • Best Views:
    • Submento-Vertex View: Effective for assessing the base of the skull and related fractures.

Maxillary Sinus

  • Structures: Maxillary sinus, zygomatic bone.
  • Best Views:
    • Waters View: Excellent for visualizing the maxillary sinus and any associated fractures.

Fractures of Zygoma

  • Structures: Zygomatic bone, zygomatic arch.
  • Best Views:
    • Waters View: Good for assessing zygomatic fractures.
    • PA View: Provides a frontal view of the zygomatic bone.
    • Reverse Townes View: Useful for visualizing the zygomatic arch.

Nasal Septum

  • Structures: Nasal septum, nasal cavity.
  • Best Views:
    • PA View: Useful for assessing the nasal septum and any associated fractures.

Condylar Neck Fractures

  • Structures: Mandibular condyle, neck of the condyle.
  • Best Views:
    • Lateral Oblique View (15°): Good for visualizing condylar neck fractures.
    • Transpharyngeal View: Useful for assessing the condylar region.

Medially Displaced Condylar Fractures

  • Structures: Mandibular condyle.
  • Best Views:
    • Lateral Oblique View (30°): Effective for visualizing medially displaced condylar fractures.

Coronoid Process of Mandible

  • Structures: Coronoid process.
  • Best Views:
    • PA View of Skull: Can help visualize the coronoid process.

Fractures of Ramus and Body of Mandible

  • Structures: Mandibular ramus, body of the mandible.
  • Best Views:
    • Lateral Oblique View (15°): Useful for assessing fractures of the ramus and body of the mandible.

Horizontal Favorable and Unfavorable Fractures of Mandible

  • Structures: Mandible.
  • Best Views:
    • Lateral Oblique View (30°): Effective for evaluating horizontal fractures.

Bony Ankylosis of TMJ

  • Structures: Temporomandibular joint.
  • Best Views:
    • CT Scan: Provides detailed imaging of bony structures and ankylosis.

Fibrous Ankylosis of TMJ

  • Structures: Temporomandibular joint.
  • Best Views:
    • CT Scan: Useful for assessing fibrous ankylosis.

Internal Derangement of the Disk

  • Structures: TMJ disk.
  • Best Views:
    • MRI: The best modality for evaluating soft tissue structures, including the TMJ disk.

Disk Perforation

  • Structures: TMJ disk.
  • Best Views:
    • MRI: Effective for diagnosing disk perforation.

Arthrography

  • Structures: TMJ.
  • Best Views:
    • Arthrography: Can be used to assess the TMJ and visualize the disk and joint space.