Other considerations in assessing the Anterior Chamber Angle

  A.    Observation begins at the pupillary border
    i.    Blood vessels
      a.    Normal blood vessels
        1.    Most often seen in light irides when vessels are congested
        2.    Usually do not bleed
        3.    Radial iris vessels
          a.    At the iris root and disappear into the mid-zone of iris 
        4.    Radial ciliary body vessels
          a.    The least common
          b.    Run perpendicular to the plane of the iris
                Do not run along the length of the iris 
          c.    Thicker than neovascular blood vessels
        5.    Circular ciliary body vessels (most common)
          a.    From the major arterial circle of the iris
          b.    Run along the surface of the iris
      b.    Differentiation of neovascularization from rubeosis
        1.    Neo arises from the pupillary border
        2.    Thin vessels - Run along the surface of the iris
              Circular ciliary body vessels are thicker 
              and originate from the CBB area 
    ii.   Deposition of exfoliation material
    iii.  Iris atrophy
    iv.   Iris cysts

  B.    Note contour of the iris plane
    i.    Is it flat, concave, or convex
    ii.   In normal adults, slightly convex
    iii.  Flat in myopes
    iv.   More convex in hyperopes and with age (due to nuclear sclerosis)

  C.    Angular approach
    i.    Refers to the width of the angle recess
    ii.   Angle recess
      a.    Bounded posteriorly by the root of the iris and anteriorly by 
            the posterior TM
      b.    It is the distance separating the inner portion of the TM from
            the adjacent anterior surface of the iris
      c.    Should be at least 25 degrees to be considered open
        1.    Angle recess of 20 degrees is in danger of closing
      d.    Vault of the angle recess is formed by the CB
      e.    Root of the iris
        1.    Zone of iris between its last roll (Fuch's roll) and its
              insertion into the anterior surface of the CB
          a.    Most peripheral portion of the iris
        2.    Determines the width of the angle recess
        3.    The more posteriorly the iris inserts, the wider the angle

  D.    Gender
    i.    Males have slightly larger anterior chamber angles than females

  E.    Miscellaneous
    i.    Diurnal shift:  angle is shallowest in the late afternoon
    ii.   Width of angle by quadrant
      a.    Superior is narrowest then nasal
      b.    Inferior is widest then temporal
      c.    Normal difference between quadrants is only a half structure
        1.    If have a greater difference, due to
          a.    Tilting away from the angle
          b.    Or patient is not looking straight ahead
    iii.  To obtain clearer views
      a.    Make sure slit lamp beam is parallel to the axis of the mirror 
      b.    Front of the goniolens should be perfectly straight
    iv.   To avoid getting bubbles
      a.    Use an adequate amount of solution to start
      b.    Do not tilt the lens excessively or have patient look at
            extremes of field of gaze
      c.    Press the lens firmly against the cornea
    v.    To remove bubbles
      a.    Tilt (rock) the lens slightly back and forth
      b.    Have the patient look toward the bubble
      c.    Have the patient alter field of gaze while pressing against
            the cornea with the lens
    vi.   Decrease IOP with gonioscopy by forcing aqueous out of the
          anterior chamber
    vii.  To avoid popping the lens while rotating, have the patient look
          straight ahead and press the lens firmly against the eye