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an office procedure does not preclude subsequent operative

intervention. Still, patients with advanced airway compromise

or concerning medical comorbidities are not appropriate for

treatment in an office setting, and some patients will demon-

strate recalcitrant anxiety to these procedures. In our study,

all patients without an obvious airway concern were at least

offered an office-based procedure; we do not, however,

include patients in the present study who were not amenable

to office treatment due to the above limitations.

Surgical lasers fall into 2 broad categories: cutting/ablating

lasers and photoangiolytic lasers.

Photoangiolytic lasers,

including KTP and PDL, selectively target hemoglobin and

are therefore most often used to manage highly vascular

lesions. Reinke’s edema is characterized in part by vascular

congestion and stasis within the superficial lamina propria.

2,23

While the exact mechanism of the laser-tissue interaction in

benign lesions remains under investigation, it is theorized that

photoangiolytic laser energy is effective in improving polypoid

degeneration by ablating damaged microvasculature within the

SLP, ultimately inducing regression of nonvascular pathologic

tissue.

It has been proposed that localized energy delivery

causes a nonspecific inflammatory response, leading to selec-

tive and time-dependent expression of inflammatory cytokines

such as transforming growth factor beta 1 and cyclooxygenase

25,26

as well as procollagen/collagenase genes such as matrix

metalloproteinases.

26,27

These changes are thought to result in

favorable alterations in tissue remodeling. As such, in contrast

to classical surgical interventions designed to physically

remove excessive tissue, laser therapy is thought to induce a

favorable biochemical shift—a biological solution for a biolo-

gical problem.

In our procedures, energy delivery is titrated to a point of

superficial blanching of tissues. No immediate reduction of

tissue mass is seen; instead, functional improvement is

expected after a period of tissue remodeling. In our study,

an average of 132 J was delivered per procedure; however,

optimal laser settings and energy titration end points remain

undefined. Efforts are underway to characterize these para-

meters. A recent study examined outcomes for Reinke’s

edema as a function of laser parameters and initial treatment

effects; the average energy applied was 157 J delivered over

a 0.369-second exposure time, and voice outcomes were

favorable.

In an effort to standardize measurement, a vali-

dated classification schema was recently proposed to estab-

lish a consistent means for measuring response to the KTP

laser.

24,29

The present study adds to this growing body of

work beginning to evaluate the relationship between amount

of energy delivered and treatment outcome.

The patients in our series underwent comprehensive voice

analyses before and after completing an intervention, allowing

for detailed evaluation of treatment effect. Acoustic measures

improved significantly; patients demonstrated improved fre-

quency range due to a higher posttreatment maximum funda-

mental frequency, representing an improvement in the classic

‘‘low pitched voice’’ reported by many patients. Percent jitter

also improved after treatment, perhaps reflecting improved

vocal fold symmetry after tissue remodeling. Changes in

aerodynamic parameters were less pronounced. MPT, laryngeal

resistance, mean airflow rate, and peak pressure did not signifi-

cantly improve following treatment. This may in part be influ-

enced by selection bias, as patients with significant airway

compromise—and thus, likely, the most abnormal pretreatment

aerodynamic profiles—were not offered office procedures.

Phonation threshold pressure did, however, improve after treat-

ment. Finally, our patients demonstrated improvement in all

subcategories of the Voice Handicap Index—functional, physi-

cal, and emotional. This perhaps more than other measures sug-

gests the utility of these procedures.

Some aspects of the present study may require clarifica-

tion. First, some individuals showed worsening of certain

voice measures after treatment. For example, 1 patient

showed increased phonation threshold pressure and airway

resistance after a second laser treatment, and 3 patients had

decreased MPT after treatment. Also, note that 6 patients

underwent multiple procedures. The decision for repeat

treatment was based on clinical assessment of recurrent or

persistent Reinke’s edema with ongoing dysphonia rather

than on objective voice data.

While unsedated endoscopic procedures are possible in

the majority of patients, anatomic and physiologic limita-

tions as well as anxiety-related factors will represent a bar-

rier in some patients. Of the 25 procedures presented here, 5

were truncated due to patient intolerance. All patients were

active smokers at the time of treatment; it is possible that

reactive airway physiology contributed to this high rate of

intolerance. Our database did not include which patients

ultimately underwent operative interventions, but it is likely

that some did. Given this limitation, we are unable to assess

voice changes related to subsequent surgical intervention

and therefore cannot comment on voice outcomes in these

patients. Importantly, no patients required emergent airway

intervention during or immediately after the procedure, had

significant bleeding, or required hospitalization immediately

following the procedure. As such, office-based laser treat-

ments in our series were safe.

The present study has several important limitations. As a

retrospective analysis without a control group, we cannot

determine whether the changes in voice parameters

observed after treatment were actually due to the interven-

tion or simply reflect normal temporal variation of the dis-

ease. Second, although this is the largest series of patients

undergoing photoangiolytic laser therapy for Reinke’s

edema, our sample size is still modest. Further, complete

data sets were not available for all patients. This reduced

our effective sample size for the pre- and posttreatment

analyses and precluded detailed analysis of parameters over

longer periods. Finally, our data set did not provide a stan-

dardized means for follow-up; as such, patients who devel-

oped complications following the conclusion of their

procedure may not be included.

As office-based procedures become increasingly more

common, there are many points for further study. Definition

of laser settings to optimize tissue remodeling remains an

important and active area of investigation. Prospective

Koszewski et al