Summit Apex Plus Laser System

Overall Rating:  C

NOTE!: This laser is no longer being manufactured.

Overview:  The Summit OmniMed Laser System was the first excimer laser system approved by the US FDA for use on refractive patients in 1995.  Although highly advanced by 1995 standards, the fundamental laser delivery has changed only cosmetically since that time.  The current Summit Apex Plus excimer laser is a broad beam laser that is maximally capable of producing a 6.5 mm optical zone. 

Advantages:

• Because the Summit technology is now considered a “dinosaur” by most refractive surgeons the laser technology itself is less expensive that the newer more advanced laser systems.  This decreased cost can be transferred to the patient in the form of a less expensive procedure.  It should be noted that Summit recently paid millions of dollars to purchase Autonomous Technologies, thereby demonstrating that, even at a corporate level, Summit does not believe in their Apex platform as the technology for today or for tomorrow. 

  Summit Ablation Profile

Disadvantages: 

• No eye tracker either manual or automated.  Surgeon must physically move the patient’s head to compensate for involuntary or voluntary eye movement during the laser procedure.
• No computerized high-speed eye tracker is available.  Excellent surgical outcomes are subject to the variable nature of patient fixation.  Eye movement (either voluntary or involuntary), head bobbing from pulsations from the heart and patient breathing all serve to compromise the visual outcome.  It should be understood that all patients exhibit erratic involuntary eye movements during a laser procedure regardless of their skills of concentration.  Irrespective of the surgeon’s skill or experience, these are variables that cannot be controlled intra-operatively. 
• Surface profile more irregular and “rougher” than more advanced laser systems due to ridging by the metal diaphragm, lack of homogeneity of the laser beam and variability in the density of the ablatable plastic disc.  Surface irregularities stimulate corneal healing resulting in proportionately greater variations in refractive results, irregular healing, optical aberrations, and poorer predictability.
• Intra-operative eye movement by the patient routinely results in macroscopic irregularities on the cornea.  As a consequence, the Summit Apex Plus surface profile is ultimately more irregular than advanced eye-tracking laser systems due to ridging caused by this erratic eye or body movement by the patient.  Surface irregularities stimulate corneal healing resulting in proportionately greater variations in refractive results, irregular healing, optical aberrations, and poorer predictability.
• More prone to create unwanted side effects such as nighttime glare or halos due to limitation of a 6.0 to 6.5 mm optical zone.  Treating to 8 mm or larger is ideal.
• Unable to treat combined farsightedness and astigmatism.  This is because it is difficult to perform farsighted corrections without an eye tracking system.  Farsighted laser ablation times are typically on the order of minutes.  Patient movement due to involuntary eye movement or loss of fixation on the blinking diode light can result in de-centered treatments, induced irregular astigmatism and loss of vision.
• Fails to provide the surgeon with the ability to “enhance” over corrections especially those with residual astigmatism.  As a consequence, the Summit Apex Plus system is unable to effectively treat this surgical complication thereby leaving the patient with sub-optimal vision.  Very difficult to enhance over-corrected nearsighted patients because lower limit for hyperopia is +1.50 diopters.  The latter patients must either wait for further FDA approval for the Summit system or pay additional fees to have the correction on a more advanced laser system.

•  Inability to finely adjust the laser system to correct small degrees of refractive error. As a consequence patients may often be left with visually significant amounts of residual refractive error.  Patients must be willing to accept the fact that although they will be “free” of glasses or contact lenses, their uncorrected vision may not be as good as their vision with glasses. 

• Unable to compensate for rotational eye movements during the laser procedure thereby often compromising the lasers accuracy in treating astigmatism.  Ignoring rotational eye movements ultimately results in less accuracy and less predictability in the surgical outcome.

• No “hinge” protection software capabilities increasing the chance for laser damage to the hinge area of the corneal flap during LASIK surgery.

• Heat generated at the corneal surface by a large laser beam appears to be greater than with small spot scanning laser technology.  This heat may cause increased damage to the cellular structure of the cornea and either delay or compromise corneal healing.

• Summit Apex Plus system is more prone to develop central “islands” or surface irregularities due to poor laser beam homogeneity, laser “plume” shadowing or corneal fluid migration than small beam scanning laser systems.  These are problems which chronically plague broad beam laser technology
• Significant acoustic shock wave damage compared to other laser systems resulting in more potential damage to the crystalline lens, retina and other delicate eye structures located deeper in the eye.
• Mechanically unstable optical system can result in misalignment of laser optics resulting in poor or unpredictable refractive outcomes

Link to Summit Web Site – www.sum-tech.com