Ms. Anne E. Rosse
Beckman Laser Institute
1002 Health Science Road E.
Irvine, CA 92715
Phone: 714-824-4111
Fax: 714-824-8413
Email: aerosse@uci.edu
Projects are approved by an IRB located at: Beckman Laser Institute/UC Irvine.
The approving IRB operates under a Multiple Project Assurance (MPA) recognized by DOE or by the Department of Health and Human Services (HHS).
MPA number of the IRB: M-1305
Number of Human Subjects Projects reported: 1
Project Identifier: UCI-91-ER61227
Project Title:
A center of excellence for the medical application of lasers
Principle Investigator:
Dr. Michael W. Berns
Principle Investigator's Institution: UC Irvine
Project started in: 1991
Project Funding Information:
Project received funding in Fiscal Year 1995.
Project used human subjects in Fiscal Year 1995.
Funding Sources:
Total Funding: $6,500
Project involves use of multiple protocols/subprojects.
Number of protocols/subprojects associated with this project: 8
Protocol/Subproject # 1
Protocol/Subproject Identifier: HS94*200
IRB Review:
Type of Review: Full Board
Most Recent Approval: May 31, 1996
IRB Approval Number: HS94*200
Number of Human Subjects in the Last Reporting Period for this Project: 10
(Reporting periods vary.)
Type of Human Subjects Involvement:
19a. Objectives
The objective of the study is to obtain data, on dose-ranging as well as clinical efficacy and safety, on the use of dynamic cooling during pulsed laser treatment of PWS.
19b. Methodology
This is a single center, open study to explore dose response relationships of dynamic cooling at varying cryogen spurt durations during pulsed laser exposure, and to determine safety and efficacy in treated patients having PWS. Subjects will be recruited from an on-site population of approximately 250 previously laser-treated or previously untreated patients at the Beckman Laser Institute and Medical Clinic, University of California, Irvine. There are no limitations in terms of skin distribution of the PWS. Successive patient groups will be given longer durations of the cryogen spurt (range 0-20 milliseconds) and within each group, escalating light doses (range 5-10 J/cm2). On each patient, test sites will be compared and evaluated for efficacy and safety of the test doses. Eighteen circular sites will be treated with different cryogen spurt regimes: six sites will be treated without dynamic cooling; six adjacent sites will be treated immediately after a 10 millisecond cryogen spurt; and six adjacent sites will be treated immediately after a 20 millisecond cryogen spurt.
Efficacy will be determined by cryogen spurt duration/light doses necessary to produce clinically significant blanching without adverse effects of treated PWS sites compared to uncooled sites and untreated control sites.
19c. Not applicable.
19d. Involvement of Human Subjects
Treatment Visit
Patients will be allocated a sequential identification number and assigned to
treatment. It should be noted after such assignment, all subjects including
drop outs must be accounted for and fully documented through withdrawal or study
completion.
In each subject, eighteen test sites on the PWS will be chosen for clinical study. All sites will be circular in shape, 5 mm in diameter and identified by a skin marker. Six sites (numbered 1,4,7,10,13,16) will be selected for irradiation without dynamic cooling. Six adjacent sites (numbered 2,5,8,11,14,17) will be selected for identical light doses of irradiation immediately after a 10 millisecond cryogen spurt. Six adjacent sites (numbered 3,6,9,12,15,18) will be selected for identical light doses of irradiation immediately after a 20 millisecond cryogen spurt. Before laser irradiation all numbered sites will be photographed under standardized conditions for film, light source and exposure. Incremental dosages of light (range 5-10 J/cm2, in increments of 1 J/cm2) will be applied ranging from the lowest in sites 1,2 and 3 to the highest in sites 15,16 and 17. A surgical drape will be used to define the study sites and to protect the remaining skin from exposure. Subjects will wear protective eye glasses to shield their eyes during the light treatment.
Risks/Discomfort/Inconveniences
Possible adverse effects are as follows:
- hypertrophic scarring
- changes in the normal skin pigmentation or color
- atrophy
- induration
- frostbite
- local skin allergic reaction to the cryogen
Previous studies cited above using the flashlamp-pumped pulsed dye laser for the
treatment of PWS have reported an incidence of adverse effects of less than 2%.
Flashlamp-pumped pulsed dye laser treatment is likened to "a rubber band
snapping against the skin." We have found the treatment to be well tolerated by
adult patients. No local or general anesthetics are required. Prolonged skin
exposure to the cryogen can cause frostbite. However, the proposed application
of a 0-20 millisecond aerosol cryogen spurt is not expected to cause frostbite
and, therefore, does not constitute a significant risk to subjects participating
in this study.
The possibility of a local skin allergic reaction to the cryogen does exist and participating subjects will be followed closely. Skin allergic reactions will be assessed on a five point scale:
SKIN ALLERGIC RESPONSE SCORE
No reaction; identical to surrounding non-irradiated skin 1
Minimal perceptible erythema; blotchy areas of faint erythema 2
confined to the irradiated site
More pronounced, even bright, erythema without edema 3
Marked erythema with edema 4
Violaceous erythema with vesiculation 5
Adverse Effects Reporting
Safety will also be evaluated at each visit by searching for any adverse effects
such as hypertrophic scarring, changes in the normal skin pigmentation, atrophy
or induration. Additional photographs will be taken during the course of the
study of any adverse effects.
Adverse effects monitoring will consist of those symptoms, complaints, or effects reported by subjects or investigators. Subjects will be asked about their symptoms, complaints, or adverse effects at each evaluation visit, and the information recorded on the Adverse Experiences form. Any severe or unexpected adverse experiences, any increase in the frequency of adverse experiences or death that may occur in this study will be reported immediately to the Institutional Review Board together with an evaluation as to whether or not the adverse experience is in any way related to the treatment. The initial report will be made by telephone and will be followed by a complete written report within five working days. The structure of the described protocol, close clinical supervision and an awareness of the potential adverse reactions provide a significant margin of safety for this investigation. Vital signs monitoring will take place only at baseline.
Informed Consent Procedures
Informed consent will be obtained from all subjects. The principal investigator will explain the full details of the protocol, experimental procedure, possible side effects, risks, and complications of the treatment to each participant before informed consent is sought and documented on the standard University of California, Irvine consent form. The subject will then be given the opportunity to sign the informed consent form in the presence of the principal investigator and a witness, who will also sign the informed consent. The patient will be informed that he or she may withdraw his consent at any time during the course of the study without prejudice to further care. The patient will be given a copy of the informed consent to keep, and a copy will be placed as a permanent record in the patient's medical chart.
Measures Taken To Protect The Rights/Welfare Of Subjects
Informed consent will be sought only after the participating physician explains the full details of the protocol, possible side effects, risks and complications to the subject. Consent will be documented by signing the standard University of California, Irvine, form. Explanation will be given of all treatment alternatives with respective advantages and disadvantages. Complete confidentiality will be maintained by staff physicians, nurses, and technical support personnel. A sequential code number for each patient will be kept in a log book and all records stored in a locked file. Patients will be identified only by their corresponding code numbers. The records and results of these studies will not be identified as pertaining to a certain patient without his or her expressed permission to safeguard the confidentiality of the subject. The data assembled will be used for research purposes only to assess the efficacy of the laser therapy and to develop optimum treatment parameters. Study progress will be monitored through monthly Operations Committee meetings. These provide the opportunity to review subject data and ensure the safety of the subjects in the unlikely event of problem situations.
IRB Review:
Type of Review: Full Board
Most Recent Approval: July 31, 1996
IRB Approval Number: HS95*326
Number of Human Subjects in the Last Reporting Period for this Project: 0
(Reporting periods vary.)
Type of Human Subjects Involvement:
19a. Objectives
The objective of the study is to obtain data on the concentration of epidermal melanin and fractional blood volume in human skin of patients with port wine stain (PWS) birthmarks using visible reflectance spectroscopy (VRS). This non-invasive, non-contact method has great potential as a means to provide quantitative data on the therapeutic response of PWS to laser therapy throughout an extended treatment protocol.
19b. Methodology
The flashlamp-pumped pulsed dye laser (FPPDL) has offered a superior approach in therapy due to its ability to destroy selectively cutaneous blood vessels. Light passing through the epidermis is preferentially absorbed by hemoglobin (the major chromophore in blood) in the ectatic capillaries in the upper dermis. There, the radiant energy is converted to heat causing thermal damage and thrombosis in the targeted vessels. Studies show that the FPPDL produces good results in the vast majority of pediatric and adult patients.
Prior to the institution of FPPDL treatment, a diagnostic measurement will be made on PWS test sites and normal skin to determine the concentration of epidermal melanin and fractional blood volume. Standard FDA-approved treatment using the FPPDL over a light dosage range of 2-10 J/cm2, which represents the standard clinical practice for subjects seen at the BLIMC, will subsequently be carried out. Untreated areas of the PWS will serve as control (no laser exposure). Test sites will be observed to determine the degree of PWS blanching. Subjects will be evaluated at 2-3 months after laser irradiation. All sites selected for treatment will be photographed before therapy is begun and at each follow up visit. At the next patient visit, a second VRS record is made. Because the majority of the most superficial PWS blood vessels were obliterated by the first laser treatment, the VRS record now measures a deeper layer of PWS blood vessels and a second treatment is performed. Proceeding in this manner, the VRS record probes deeper and deeper layers of the PWS after the more superficial layers are removed by each successive treatment at the same site.
19c. Not applicable.
19d. Involvement of Human Subjects
The rationale for using VRS in the clinical management of patients with PWS is that the technique offers a means of documenting the concentration of epidermal melanin and fractional blood volume throughout an extended treatment protocol. Prior to the institution of laser treatment, a diagnostic measurement will be made on a PWS test site and normal skin to determine the concentration of epidermal melanin and fractional blood volume. Standard FDA-approved treatment using the FPPDL will subsequently be carried out. At the next patient visit, a second VRS record is made. Because the majority of the most superficial PWS blood vessels were obliterated by the first laser treatment, the VRS record now measures a deeper layer of PWS blood vessels and a second treatment is performed. Proceeding in this manner, the VRS record probes deeper and deeper layers of the PWS after the more superficial layers are removed by each successive treatment at the same site. In conclusion, VRS offers the clinician a direct means of documenting the concentration of epidermal melanin and fractional blood volume throughout an extended treatment protocol.
Risks/Discomforts/Inconveniences
No venipuncture or other invasive procedure, such as biopsy, will be performed. The study entails minimal risk to the subject. The intensity of the source light is less than that associated with the flash of commercially available cameras. Laser therapy of PWS has been approved by the FDA. A physician will be present throughout the study.
Measures Taken To Protect The Rights/Welfare Of Subjects
Informed consent will be sought only after the participating physician explains the full details of the protocol, possible side effects, risks and complications to the subject. Consent will be documented by signing the standard University of California, Irvine, form. Explanation will be given of all treatment alternatives with respective advantages and disadvantages. Complete confidentiality will be maintained by staff physicians, nurses, and technical support personnel. A sequential code number for each patient will be kept in a log book and all records stored in a locked file. Patients will be identified only by their corresponding code numbers. The records and results of these studies will not be identified as pertaining to a certain patient without his or her expressed permission to safeguard the confidentiality of the subject. The data assembled will be used for research purposes only to assess the efficacy of the laser therapy and to develop optimum treatment parameters. Study progress will be monitored through monthly Operations Committee meetings. These provide the opportunity to review subject data and ensure the safety of the subjects in the unlikely event of problem situations.
IRB Review:
Type of Review: Expedited
Most Recent Approval: July 14, 1995
IRB Approval Number: HS94*330
Number of Human Subjects in the Last Reporting Period for this Project: 0
(Reporting periods vary.)
Type of Human Subjects Involvement:
19a. Objectives
Specifying the distribution of laser energy within human skin is the first step toward understanding and capitalizing on a variety of laser-tissue interactions. Whether photothermal, photochemical, or photomechanical in nature, laser-tissue interactions begin with the absorption, scattering, transmission, and reflection of photon energy. The spatial distribution of photon energy within human skin specifies the required laser exposure to be delivered and the extent of subsequent therapeutic action.
19b. Methodology
Optical low coherence reflectometry (OLCR) or white light interferometry are existing techniques whereby the location and relative strength of optically scattering structures can be deduced. Results from OLCR are analogous to ultrasound B-scan except the imaging is performed optically instead of acoustically. However, OCLR is far superior to ultrasound in that the technique is non-contact, has high sensitivity (>140 dB dynamic range) and, most importantly, exceptional spatial resolution (<1 mm) in both the axial and radial directions. In practice, light emitted from a low coherence source is coupled into a two beam fiber optic interferometer and split into sample and reference paths. Light backscattered by the test material is recombined with that retroreflected from the reference to produce interference only for coherent photons that have a time-of-flight difference that matches the reference-target optical delay to within the source coherence length.
Infrared tomography (IRT) uses a fast infrared focal plane array (IR-FPA) camera to detect temperature rises in a substrate, induced by pulsed radiation. The temperature rise, due to the selective optical absorption of pulsed laser light, creates an increase in infrared (blackbody) emission which is measured by a fast IR-FPA. Although the use of IRT has become a topic of great interest in the physical sciences to image subsurface cracks in aircraft fuselage due to metal fatigue, the application of this modality to determine the initial space-dependent temperature increase in absorbing subsurface chromophores in human skin immediately following pulsed laser exposure is novel.
19c. Not applicable.
19d. Involvement of Human Subjects
We propose to use OLCR and IRT to measure the absorption, scattering, transmission, and reflection of photon energy within human skin. Discarded skin samples will be collected by Dr. Bruce Achauer, Associate Professor of Plastic Surgery, University of California, Irvine, from patients undergoing elective rhytidoplasty ("face lift") and abdominoplasty ("tummy tuck") surgical procedures. The epidermal and dermal papillary layers will be non-destructively isolated using a standard technique developed in the Department of Dermatology, University of California, Irvine. After isolation, each layer will be slowly heated with a temperature controlled gel pack. The pliable gel pack will allow good contact and insulation of the tissue sample under test. Using OLCR and IRT, the absorption, scattering, transmission, and reflection of photon energy within human skin will be measured. The experimental procedure will be conducted with a number of skin samples so that statistically significant conclusions can be made.
Every effort will be made to obtain skin samples from the appropriate gender and minority/ethnic background representation that reflects the general population distribution seen at the University of California Irvine Medical Center. This protocol is being filed as Exempt Research under Category #4 because the work involves the collection of data from discarded pathological specimens by the investigator in such a manner that the subjects cannot be identified directly or through identifiers linked to the subjects.
IRB Review:
Type of Review: Full Board
Most Recent Approval: November 07, 1994
IRB Approval Number: HSM90*229
Number of Human Subjects in the Last Reporting Period for this Project: 25
(Reporting periods vary.)
Type of Human Subjects Involvement:
19a. Objectives
The objectives of this study are to determine the safety and effectiveness of the clinical use of the excimer laser in treating the human cornea.
19b. Methodology
The study measures: (1) refraction and visual acuity, (2) shape of the cornea, (3) complications, and (4) patient satisfaction to achieve the following:
1. Assess the safety of the procedure during the immediate and long term postoperative periods by numerous complete ocular examinations of the treated eye.
2. Determine the effectiveness of the excimer laser as a surgical device for the treatment of mild to severe ametropia. Patient's refraction will be evaluated to determine the quality and stability of vision and the associated improvement in visual function.
19c. Not applicable.
19d. Possible risks are glare or light sensitivity, fluctuating changes in vision, or repeat surgery. Vision may be worse. There may be a slight amount of discomfort usually relieve by aspirin or Tylenol. Patients may experience a milky appearance to the eye, a small amount of bleeding, or a small ulcer or infection. A small perforation of the cornea may occur, but it is unlikely. New complications may be observed as the surgical procedure develops in the future and long term effects of the excimer laser are known. There is also a possibility of other complications due to the anesthesia, drug reactions, or other factors which may involve other parts of the body.
IRB Review:
Type of Review: Full Board
Most Recent Approval: June 27, 1995
IRB Approval Number: HSM91*252
Number of Human Subjects in the Last Reporting Period for this Project: 60
(Reporting periods vary.)
Type of Human Subjects Involvement:
19a. Objectives
The broad long term objective of the proposed research is the development of Photodynamic Therapy (PDT) for application in the clinical management of patients with port wine stain (PWS) malformations.
19b. Methodology
PDT involves the use of an exogenous drug which is concentrated in a targeted tissue. When irradiated at wavelengths specifically absorbed by the drug, selective destruction of agents for imaging and eradication of neoplastic diseases has become a topic of great interest in the medical field. The application and usefulness of this modality for the treatment of PWS is novel.
19c. Photofrin II.
19d. Involvement of Human Subjects
Phototherapy is commonly associated with some degree of local burning, erythema, and edema of the treatment site. Necrosis of the treatment site is a rare event which can be minimized by preliminary testing with low incident light doses and subsequent dose escalation based on previous cutaneous response. Subjects will be fully informed regarding the potential for skin photosensitivity and will be provided with prepared photosensitivity educational materials explaining to them in detail precautions to avoid this side effect as well as a resource person to contact should problems arise.
IRB Review:
Type of Review: Full Board
Most Recent Approval: January 31, 1996
IRB Approval Number: HSM91*30
Number of Human Subjects in the Last Reporting Period for this Project: 8
(Reporting periods vary.)
Type of Human Subjects Involvement:
19a. Objectives
Port wine stain (PWS) is a congenital vasculopathy that occurs most commonly on the face and neck. The chief complication of PWS is psychological disability, particularly in young children. Personality development is adversely affected in a large percentage of patients due to the negative reaction of others to a "marked" person. PWS has been treated in the past with an array of therapeutic modalities including skin grafting, radiation therapy, cryosurgery, electrocautery, sclerosing agents, tattooing and cosmetic camouflage. All of these have met with limited success, unpredictable results, or serious complications. The laser provided the first major advance in therapy for PWS and has been used extensively in the past two decades. Light of the appropriate wavelength is preferentially absorbed by hemoglobin and converted to heat, causing thermal damage and thrombosis in the targeted vessels. However, because of the complex nature and individual variability in the optical properties of human skin and vasculopathy, optimal clinical results (i.e., significant blanching) are not always forthcoming. Presently, all patients are treated with incident doses of light based on the clinical judgment of the physician without taking these important tissue properties into consideration. Such lack of specificity in choosing the light dose for therapy is the primary reason for poor clinical results or complications, such as hypertrophic scarring or changes in the normal skin pigmentation, seen after laser therapy. There is a definite need for non-invasive measurements to be made on each patient to predict the threshold light dose that causes damage to the normal overlying epidermis. It is obvious that a method that considers individual variations in the optical properties of the skin, on a case by case basis, would have decided advantages over existing methodology.
19b. Methodology
Pulsed photothermal radiometry is a non-invasive temperature measurement, using remote thermal and optical sensing techniques. PPTR uses a fast infrared detector to measure surface temperature rises induced by pulsed radiation. In practice, a pulsed laser is used to produce transient heating of the object under study and the subsequent temperature rise creates an increase in infrared (blackbody) emission that is measured by the detector. In this case, absorption of the laser pulse produces an initial temperature "jump" ("T-jump") which denotes the temperature of the sample surface. The initial "T-jump" can then be used to calculate the epidermal absorption coefficient (ľa). Once ľa has been determined, because there is a linear relationship between the incident light dose and the resulting "T-jump", "T-jumps" at a variety of light doses may be predicted.
When the epidermal surface of the skin is irradiated by a laser pulse such that the "T-jump" is 70 degrees C, the result is epidermal denaturation leading to necrosis. For temperatures in excess of 140 degrees C, the result is explosive vaporization of the epidermis. The physician must avoid both such phenomena during PWS therapy otherwise hypertrophic scarring or changes in the normal skin pigmentation will result. Thus, prior to starting therapy, the physician will know the maximum incident light dose that may be delivered without damaging the normal overlying epidermis. These thresholds will vary from subject to subject, site to site. However, since temperature can be monitored on a pulse by pulse basis, immediate feedback will be provided if damage to the epidermis is likely to occur.
A PPTR instrument is on site at the Beckman Laser Institute and Medical Clinic. A fast infrared detector senses the surface skin temperature as a function of time and the resulting signal is displayed on the oscilloscope.
Initial "T-jump" measurements will be made on PWS patient's skin at low incident (subtherapeutic) light doses. The initial "T-jump" will then be used to calculate the epidermal absorption coefficient (ľa) for each patient. Once ľa has been determined, the threshold incident light dose that results in epidermal damage will be established. Thus, before starting therapy, the physician will know the maximum incident light dose that may be delivered without damaging the normal overlying epidermis. Laser treatment will then proceed normally with the physician being careful to use an incident light dose far below that predicted by PPTR to cause epidermal damage.
19c. Not applicable.
19d. Involvement of Human Subjects
Patients with (PWS) will be enrolled in this study from the population seen at the Beckman Laser Institute and Medical Clinic. Patient enrollment will include both sexes, all ethnic backgrounds and all age groups. Only pregnant females will be excluded.
Measures Taken to Protect the Rights and Welfare of Subjects
Informed consent will be sought only after the participating physician explains the full details of the protocol, possible side effects, risks, and complications to the patient, or in the case of a minor, parent or legal guardian. Consent will be documented by signing the standard University of California, Irvine form.
Complete confidentiality will be maintained by staff physicians, nurses, and technical support personnel. The data taken will be used for research purposes only to assess the efficacy of the laser therapy and to develop optimum treatment parameters. Study progress will be monitored through monthly Operations Committee meetings. This provides the opportunity to review patient data and ensure the safety of the patients in the unlikely event of problem situations. A patient may leave the study at any time.
Risks/Discomforts/Inconveniences
No venipuncture or other invasive procedure, such as biopsy, will be performed. The study entails minimal risk to the patient. The irradiation of the skin by laser light for the purposes of making skin temperature measurements is painless since subtherapeutic doses of light are sufficient. Flashlamp pulsed dye laser therapy of PWS has been approved by the FDA. A physician will be present throughout the conduct of the study.
IRB Review:
Type of Review: Full Board
Most Recent Approval: April 30, 1995
IRB Approval Number: HSM92*008
Number of Human Subjects in the Last Reporting Period for this Project: 24
(Reporting periods vary.)
Type of Human Subjects Involvement:
19a. Objectives
To determine the safety and efficacy of topically applied dihematoporphyrin ether (DHE) in the photodynamic treatment (PDT) of cervical intraepithelial neoplasia (CIN) using fixed DHE doses and applications schedules and a variable dose of 630 nm red light delivered by an argon pumped dye laser.
19b. Methodology
Between February 1993 and April 1994, 24 non-pregnant women with a histologic diagnosis of CIN were enrolled. All patients had lesions involving at least 25% of the cervix that were colposcopically visible. Using a cervical cap, 2 ml of a 1% solution of DHE (Photofrin) in a 4% Azone and isopropyl alcohol vehicle were applied to the cervix for 24 hours prior to PDT. An argon pumped dye laser providing light at 630 nm was then used to perform PDT. Light was coupled into a 400 um silica fiber optic terminating in a microlens which focused the laser radiation onto a circular field of uniform light intensity perpendicular to the tissue. The entire ectocervix was treated in a single field including a margin of 3-5 mm of normal cervix. Using a constant power density (150 mW/cm2) to avoid thermal injury, the density of the PDT energy was increased every 4 patients in a phase I study (40, 60, 80, 100, 120, 140 J/cm2).
19c. See 19b. Methodology.
19d. Involvement of Human Subjects
The risks for this treatment include a possible discomfort from the tissue biopsy; a burning irritation or possible allergic reaction, such as a skin rash and itching from the DHE solution application, and a feeling of warmth in the treatment area where the laser light is administered. When DHE is injected intravenously, it distributes throughout the body tissues and causes a tendency to sunburn normal skin when exposed to bright light up to periods of four weeks after injection. Since in this study, the drug is being applied to the surface of the body in much small quantities than with intravenous injection, the photosensitivity of skin in other parts of the body is not to be expected. Accidental exposure of the eyes to laser light could result in eye injury or loss of vision. Eye goggles will be worn during therapy to avoid eye injury. DHE can also cause staining of garments that it comes in contact with. The patient will be informed of these potential risks. For the blood tests, there is the risk of possible discomfort and bruise at the site and swelling and possibly infection as indicated in the informed consent.
The collection of medical information for this study will be accomplished with the strictest adherence to professional standards of confidentiality. An identification number for each patient will be kept on file, and all records will be filed in a locked cabinet. Patients will be identified only by their corresponding identification number.
IRB Review:
Type of Review: Full Board
Most Recent Approval: February 07, 1995
IRB Approval Number: HSM93*235
Number of Human Subjects in the Last Reporting Period for this Project: 700
(Reporting periods vary.)
Type of Human Subjects Involvement:
19a. Objectives
The objectives of this study are to determine the safety and effectiveness of the final device for PMA approval. Phase III of the study will involve the enrollment of 700 patients, intended to result in a minimum 500 patient cohort, at a maximum of 10 sites followed for two years.
19b. Methodology
Excimer laser surgery is an investigational procedure. Conventional clinical examination techniques will be employed to evaluate each patient. The clinical status of the eye, the presence or absence of pre-existing ocular pathology, and the presence of any complications will be assessed before laser surgery, at the time of surgery, and at each postoperative evaluation.
19c. Not applicable.
19d. Involvement of Human Subjects
Possible risks are glare or light sensitivity, fluctuating changes in vision, or repeat surgery. Vision may be worse. Patients will experience pain during the first 24 to 72 hours following treatment. Analgesics are prescribed for this post-operative discomfort. Patients may experience a milky appearance to the eye, a small amount of bleeding, or a small ulcer or infection. Although unlikely, a small perforation of the cornea may occur. Other complications may include: corneal edema; corneal scarring; corneal infection/ulceration; hyphema; patient discomfort; glare; cataract; bacterial keratitis; foreign body sensation; corneal epithelial defect; iritis; viral kerato conjuctivitis; BCVA post-operatively worse than pre-operatively at final visit. New complications may be observed as the surgical procedure develops in the future and the long term effects of the excimer laser are not known. There is a possiblity of other complications due to the anesthesia, drug reactions, or other factors which may involve other parts of the body.