Low-Intensity Laser Therapy for Benign Fibrotic Lumps in the Breast Following Reduction Mammaplasty.

Key Words: Fibrosis, Low-intensity laser therapy, Mammaplasty complication.

Development of benign lumps in the breast is a possible complication of both reductive and reconstructive mammaplasty.[1-3] Multiple small lesions or a single large mass may develop deep in the breast tissue within weeks of surgery.[4] Lumps have been reported to evolve as long as 3 to 7 years after surgery.[3] The lumps may be well or poorly defined, may vary from minor thickening to dense immobile masses, and may be tender and sore.[3] In some cases, a fibrous band connects the lesion to the overlying skin, causing thickening of the skin or retraction of the breast around the mass.[5] Masses that are very large may distort the shape of the breast. Over a period of years, the lesions may calcify. Although harmless, these lesions may distress patients.

Isaacs et al[3] reported 3 causes of breast lumps after mammaplasty: (1) deep hematoma may produce scarring in much the same way that hematoma produces scarring in other soft tissues, (2) fat necrosis may occur as a result of trauma during surgery or inadequate postoperative blood supply to fatty tissue remaining in the breast, and (3) operative techniques may cause fibrous scarring. Hemorrhage into the breast is not a common complication in reduction mammaplasty. Infiltration of local vasoconstrictive drugs, such as epinephrine, along the proposed skin incision lines reduces the amount of perioperative bleeding.[4] In addition, tissue drains are almost routinely used for 24 hours after surgery. If hemorrhage occurs and the fluid is not evacuated, the patient has a risk of infection and a risk of increased pressure that can reduce the blood supply of surrounding tissue, leading to fat necrosis.

Fat necrosis and hematoma in the breast are attended by an inflammatory response.[1,6] Necrotic cells become surrounded by neutrophils and macrophages, and the debris is encapsulated in a wall of fibrous tissue. The entire area may be replaced by fibrosis. The central scar tissue or the surrounding capsule may later calcify.[7] Radiological studies have shown fluid-filled cysts within the scar tissue in some cases, and surgery has revealed that cysts are filled with an oily serosanguineous fluid.[5,7,8] Some surgeons recommend debridement of the dead tissue as soon as a necrotic mass becomes delineated.[4] This approach necessitates daily wound dressing and packing of the wound crater, and always results in additional scarring.

The incidence of fat necrosis and hematoma has been reported to be 1.1% to 1.7% and 2.0% to 2.5%, respectively, in patients who were followed for 1 to 7 years alter breast reduction surgery.[1,9,10] When outcomes are considered separately for patients who had more than 500 g of tissue resected per breast, authors have noted that the risk of fat necrosis increases. Strombeck[4] reported that the incidence of fat necrosis in 581 surgeries was 1.1%; however, the rate increased to 11.1% for surgeries involving resection of more than 1,000 g of tissue per breast. Strombeck suggested that the incidence increased because circulation was more likely to be more disturbed during surgery for excessively large breasts. In a follow-up of 185 patients, Dabbah and colleagues[2] found an incidence rate of 22% for a combined group of patients with infection and patients with necrosis and an incidence of 2% for hematoma. The authors suggested that distinguishing between infection and necrosis was difficult.

Perioperative measures to decrease the risk of fat necrosis and hematoma following mammaplasty include the use of local vasoconstrictor agents, tissue drains, antibiotics, and reduced physical activity.[9,11] If lumps develop in spite of these measures, surgical evacuation or no treatment appear to be the only recommendations.[4.9] Strombeck[4] noted that after "considerable" time the lumps may soften. Lumps that develop long after surgery are usually biopsied to rule out carcinoma because the radiographic features of fibrotic tissue and carcinoma are similar.[1]

Physical therapists use low-intensity laser therapy (LILT) to treat patients with chronic inflammatory and fibrotic conditions.[12] The literature on reduction mammaplasty, however, does not mention the use of LILT as a potential treatment for fibrotic breast lumps. MEDLINE and CINAHL searches tot articles published from 1980 to 1998 failed to identify any studies reporting the use of LILT for fibrotic breast lumps.

Cellular studies support the use of LILT to improve absorption of extracellular fluid. The findings include increased neutrophil activity and chemotaxis,[13] increased secretion of macrophage growth factors,[14] enhanced DNA synthesis[15] and enhanced electron respiratory chain reaction.[16] Kiyoizumi[17] demonstrated that LILT increased endothelial [PGI.sub.2] secretion and degradation of fibrin networks. Kiyoizumi proposed that degradation of clotted blood and enhanced absorption of hematomas by improved circulation were the mechanisms by which LILT improved survival of grafted skin in cases where hematoma had developed.[17]

High dosages of LILT generally have an inhibitory effect on tissue metabolism.[13,18,19] Baxter[20] recommended dosages of 8 to 32 J/[cm.sup.2] both for the treatment of chronic inflammation and to reduce the risk of scar formation in musculoskeletal injuries. In a series of case studies, Ohshiro and Maeda[21] reported using a similar approach to the treatment of scar tissue in the skin. To reduce true keloid and hypertrophic scars, they applied 830-nm LILT at a dosage of 30 J/[cm.sup.2], in combination with the use of pressure tapes or dressings and steroid injection. They used the same regimen preventatively in patients who had demonstrated a propensity to develop hypertrophic scarring. Their patients usually received LILT twice weekly, and treatment frequency was reduced once they judged that "real improvement" had occurred; total treatment was for periods of up to 1 year. The effect of LILT on scar formation has not been evaluated in a controlled study, and treatment of fibrosis or calcification secondary to hematoma or fat necrosis is not specifically mentioned in the LILT literature. The purpose of this case report is to describe the use of LILT in a patient with fibrotic breast lumps following reduction mammaplasty.

Case Description

Patient

The patient was a 46-year-old woman who was referred for physical therapy 80 days after breast reduction surgery for a trial of laser therapy on benign breast lumps. Her primary complaint was of tender lumps in both breasts, with more tenderness on the left side. Pain in the center of the breasts, associated with the recently healed surgical scars, was a secondary complaint. She seemed quite distressed because of the pain and the noticeable distortion in her left breast. Her general health was good, and her past medical history was not relevant to the present problems.

The patient stated that the surgical procedure was uneventful. The amount of tissue resected was 614 g from the right breast and 644 g from the left breast. Tissue drains were removed within 24 hours of the surgery, and she was discharged home with dressings and supportive bandages.

On the third postoperative day, she returned to the hospital because of a fever and severe swelling and pain in the breasts, especially on the left side. She stated that a large amount of fluid discharged from the left breast when the surgeon released some stitches. She was sent home with antibiotic medications and nonprescription analgesics. She stated that her breasts were tender at this time and that a mass developed in the left breast and enlarged over the following weeks. Smaller masses developed in the right breast. Her surgeon diagnosed fat necrosis at a follow-up visit during the second month after surgery.

Examination

All of the incisions were found to be healed. The scars were pinkish and did not appear hypertrophic. The medial ends of the horizontal scars and the T-junctions where the vertical and horizontal scars joined had some thickening.

The patient described the breast pain as constant and stabbing in nature and complained of hypersensitivity (light touch caused painful sensations) of the healing scars around the areola and in the submammary fold of both breasts. She rated her pain as 8/10 using a verbal pain scale (VPS) that had a range of 0 to 10, with anchor points of "no pain" and "worst pain ever." Reliability of numerical rating scales for pain has been demonstrated.(22) The patient required nonprescription analgesics twice daily and stated that she was sleeping poorly.

Palpation of the right breast revealed the presence of 2 small, tender, very firm masses, each measuring approximately 2.0 [cm.sup.2] in surface area, in the superior pole of the breast. The masses were mobile in relation to the skin and the underlying breast tissue. Palpation of the left breast revealed the presence of a very tender, very firm, immobile mass, about the size of a small orange, lying in a retroareola position and occupying most of the medial compartment of the breast. The portion under the areola was superficial and particularly tender, and the mass appeared to be attached to the skin in this region. The periphery of the mass was sharply defined, but the depth could not be ascertained from palpation.

I recorded the surface area of the mass using transparent film and indelible ink (Fig. 1). The method involved placing film over the breast, palpating the margin with a fingertip of one hand while following the finger with a felt-tipped pen held in the other hand. Although I did not assess the reliability of this method to measure subcutaneous masses, tracing the margin of open skin lesions is a reliable measure for superficial ulcers.[23] A MEDLINE review of articles published from 1995 to 1998 revealed no clinical methods for measuring the area of subcutaneous masses. Magnetic resonance imaging, diagnostic ultrasound, and computed tomography are reliable methods for measuring the size of soft tissue masses,[24,25] but they are not practical for day-to-day measurement in physical therapy practice.

[Figure 1 ILLUSTRATION OMITTED]

Treatment

The referring surgeon requested a trial of LILT for the patient's problems based on unconfirmed reports that LILT was effective in the treatment of hematoma and fat necrosis following breast reduction surgery. I was unable to locate a specific protocol for LILT treatment in this condition, and the surgeon was unable to recall the source of her information.

My previous experience using LILT includes the treatment of people with chronic ulcers and soft tissue contractures following severe musculoskeletal injury and the management of chronic inflammatory conditions, such as long-standing tendinitis and osteoarthrosis. Based on outcomes treating people with adhesions and contractures involving the upper extremity, I believed that a trial of LILT was appropriate to address the problems of fibrosis and pain.

The purported benefits and risks of LILT were explained to the patient, and treatment was initiated with the patient's consent. The characteristics of the laser unit used for treatment are shown in Table 1. A direct-contact method was used for all irradiation. Treatments were applied twice weekly. Pulse repetition rate (PRR) and dosage, or energy density (ED), were adjusted during the treatment time flame.

Table 1.

Characteristics of the Laser Diode

Model                             Intelect 800(a)
Wavelength                        820 nm
Average power output              50 mW
Beam spot size                    0.1256 [cm.sup.2]
Power density                     0.39 W/[cm.sup.2]
Pulse repetition rate options     2.5, 5, 10, 16, 20, 40, 80, 160,
                                  292, 700, 1,000, 5,000

(a) Chattanooga Corp, PO Box 4287, Chattanooga, TN 37405.

Initial treatment included irradiation to the healing surgical scars to reduce pain and to the surface of each fibrotic mass. A PRR of 16 pulses per second (pps) and an ED of 4 J/[cm.sup.2] were selected for treatment of pain. These laser characteristics were based on previous clinical experience and on studies that evaluated the hypoalgesic effects of low-energy-density LILT at low PRR on experimental pain in animals and humans.[26,27] Baxter[20] recommended dosages of 4 to 8 J/[cm.sup.2] to accelerate late soft tissue healing. Scars were irradiated at 1-cm intervals around the areola and along the vertical and horizontal incision lines of both breasts. The laser probe was applied without pressure because the patient complained of tenderness.

It was difficult to decide on effective dosages of therapeutic laser to treat the breast masses, given the paucity of laser studies and contradictions in the literature. The aim of treatment was to degrade fibrin clots and increase absorption of the resulting cellular debris. I reasoned that because the lesions were chronic, dosages should be greater than those recommended by Baxter[20] to resolve acute hematomas. I believed that the dosage should be similar to that used by Ohshiro and Maeda[21] (ie, 30 J/[cm.sup.2]) to reduce hypertrophic scarring. Due to a lack of experience in treating breast tissue, however, I decided to observe the response to a more conservative 20-J/[cm.sup.2] dosage of LILT. If the response was inadequate, I would increase the dosage incrementally over 3 or 4 treatments, up to 30 to 50 J/[cm.sup.2] which is a dosage that I use routinely in orthopedic conditions to treat soft tissue contractures, tendinous adhesions, and fibrotic tissue.

I selected a PRR of 5,000 pps based on studies that demonstrated increased macrophage activity and wound healing in animals, using various wavelengths of laser, including 820 nm, at various PRRs, including 16 and 5,000 pps.[28,29] Wavelength and PRR are variables of LILT that affect the treatment outcome.[14,18] Therefore, it was important for me to search the literature for evidence of wound healing using a laser with wavelength and PRR characteristics that matched those of my equipment. Baxter[20] recommended using a PRR greater than 1,000 pps for treatment of people with chronic wounds and suggested switching PRR to low values when response is poor. I have used this approach previously in treating patients with chronic wounds and adhesions, switching to a PRR of less than 100 pps when the initial response to a PRR of 5,000 pps was inadequate. Each mass was treated around the periphery at 1-cm intervals and across the surface in a grid of points placed at 1-cm intervals at an ED of 20 J/[cm.sup.2] and a PRR of 5,000 pps.

Progress was measured by the patient's reported pain, by change in firmness of the mass, and by repeated tracings of the perimeter of the mass. All measurements were done by the same physical therapist. Tracings were digitized,(*) and the percentage of change in surface area was calculated (Tab. 2). Firmness was not rated using a specific tool or scale, and improvement was defined as decreased firmness as judged by the therapist.

Table 2.

Resolution of the Mass in the Patient's Left Breast as Measured by Surface Tracing

                                     Average Weekly Rate
          Surface Area as            of Resolution (%)
Tracing   Percentage of              Since Previous
No.       Original (35 [cm.sup.2])   Tracing

 1        100
 2         33.0                      42.7
 3         32.5                       0.35
 4         32.5                       0.0
 5         19.5                      16.5
 6         16.4                       6.6
 7         16.3                       0.2
 8         Tracing not available     Not available
 9         13.4                       4.62
10         13.4                       0.0
11         10.0                      11.95
12          6.1                      22.68

Figure 2 shows the patient's attendances from day of admission to day of discharge. Treatment 4 was followed by a 31-day period without treatment during the patient's vacation. Figure 2 also shows the tracing schedule. Laser dosage was increased and PRR was changed a number of times during the treatment period, as shown by the symbols in Figure 2.

[Figure 2 ILLUSTRATION OMITTED]

Outcome and Changes in Treatment

After 3 treatments, the patient stated that her pain had reduced to occasional stinging associated with the incision scars and that stabbing pains in the left breast had become intermittent and had decreased in intensity. At the time of assessment, the patient stated that she was not experiencing any pain (VPS score = 0/10).

After the vacation period, pain was unchanged from the previous assessment. Low-intensity laser therapy for pain resumed at the initial treatment settings (ie, ED=4 J/[cm.sup.2] and PRR = 16 pps) because the patient's response to this protocol had been good during the initial 11-day treatment period. Following 4 successive treatments of LILT to the scars on both breasts, the patient reported experiencing 2 to 3 instances of pain per day. She reported having no pain (VPS score = 0/10) at the time of assessment. Irradiation was reduced to 1 to 2 spots of irradiation at the medial and lateral ends of the horizontal incision lines on the left breast only. Irradiation to these spots was discontinued after 4 additional treatments.

After 3 treatments, the patient reported that the lumps felt smaller, "as if they were breaking up," and said she was pleased with the improvement. Palpation and tracing revealed a reduction in firmness and size of the masses in both breasts. On the right side, the 2 masses were each smaller than 1.0 [cm.sup.2]. A tracing (tracing 2) of the mass in the left breast prior to treatment 4 is shown in Figure 1. The mass was 33% of its original size. Low-intensity laser therapy was applied at the previous settings for treatment 4. The next assessment was after the vacation period.

After the patient's vacation, examination of the right breast revealed a small area of thickening, with poorly defined margins, deep in the right breast. Treatment resumed using the initial LILT settings (ie, ED-20 J/[cm.sup.2], PRR-5,000 pps). After 4 additional treatments, irradiation to the right breast was discontinued because the lumps had almost resolved.

After the vacation, a surface tracing of the left breast showed that the mass was 32.5% of its original size (tracing 3, Fig. 1). The average weekly rates of resolution for the periods with and without laser treatment were 42.7% during the 11-day initial treatment period and 0.35% during the 31-day vacation, during which the patient had no treatment.

Treatment to the left breast resumed at the initial LILT settings (ie, ED=20 J/[cm.sup.2], PRR=5,000 pps). After 4 additional treatments, however, there was no improvement (tracing 4, Fig. 2). I reasoned that because part of the mass closest to the skin had resolved, I now needed to transmit the energy to a deeper level. However, a greater amount of energy was being attenuated through the added thickness of the overlying tissue. The condition was also more chronic; therefore, I increased the ED to 40 J/[cm.sup.2] (Fig. 2). After 4 additional treatments at the higher dosage, during a 17-day period (tracing 5, Fig 2), the mass had reduced to 19.5% of its original size, representing an average weekly rate of resolution of 16.5% for the 17-day period. Palpation revealed that the mass was less firm.

The patient continued to receive twice-weekly LILT treatments to the left breast. After 4 additional sessions and a follow-up tracing (tracing 6), however, it was evident that the mass size had not decreased since the previous tracing. I decided to evaluate response to a PRR of 16 pps rather than increasing the dosage. I used LILT at an ED of 40 J/[cm.sup.2] and a PRR of 16 pps for 10 sessions because the mass appeared less firm on palpation, even though the size of the mass (tracings 7 and 8) did not change. Then, I reverted to the original PRR of 5,000 pps because firmness and size were not changing. Rate of resolution improved slightly after changing back to a PRR of 5,000 pps (tracing 9).

During the sixth month, tracing 10 showed again that the size of the mass was unchanged. I suggested discharge to the patient, but she wanted to continue. I suggested trying a final increase in ED, after which we could reassess the treatment. I increased the ED to 51) J/[cm.sup.2], and an immediate positive response occurred to the first treatment at the higher dosage. On palpation, the perimeter of the mass felt less dense, and the outline felt irregular, which was confirmed by the next measurement (tracing 11). At the time of tracing 12, the mass in the left breast was 6.1% of its original size. No further tracings were made because the mass was too small and too deep to trace accurately.

At the time the patient was discharged, I could not feel a discreet mass in the patient's left breast. I could feel a difference in firmness, however, between the region of breast tissue that had been occupied by the mass and unaffected tissue ill the same breast. Skin in the areola area was not attached to the underlying tissue.

On follow-up after a further 6 months, no additional resolution was noted. At this time, the patient's breasts were examined for the first time since the surgery by mammogram and ultrasound. The radiology report noted an asymmetric density in the 11 o'clock position in the left breast associated with a few tiny calcifications, consistent with an area of scarring and fat necrosis. Ultrasound examination showed that the corresponding hypoechoic area measured approximately 16.0 mm. A few simple cysts were noted, with the largest measuring 6.0 mm. Follow-up mammograms at 6 months and 1 year also noted the scarring centrally in the left breast associated with some architectural distortion and micro-calcifications (Fig. 3).

[Figure 3 ILLUSTRATION OMITTED]

Discussion

This case report documents the use of LILT for a patient who developed fibrotic masses in both breasts following breast reduction mammaplasty. Her physician diagnosed the condition as fat necrosis, but I do not know whether the condition developed as a result of tissue hypoxia secondary to hemorrhage or to an inflammatory response to the surgery.

Because the report concerns a single uncontrolled case, limited conclusions can be drawn. Comparison of the average weekly rate of resolution during the initial 11-day treatment period (42.7%) with the rate during the patient's 31-day vacation (0.35%) suggests that LILT might be an effective treatment for this condition. The faster rate of improvement in the initial month compared with later months suggests that initial treatment may be more beneficial than later treatment in this condition.

The dosage of laser used for the initial treatment (20 J/[cm.sup.2]) was based on recommendations by Baxter[20] and the work of Ohshiro and Maeda[21] related to chronic soft tissue inflammation and scarring. This dosage seemed appropriate because the patient had such well-defined and dense masses in her breasts. The laser dosage or PRR characteristics were changed each time the rate of progress decreased. Each increase in ED was followed by an improved rate of resolution, which appeared to be limited to a 2-week period. As the mass resolved, it was progressively farther from the surface, resulting in greater attenuation of irradiation at the level of the target tissue. A planned regimen of compensatory dosage increases every 2 weeks might have effected a steadier rate of improvement and shortened the treatment period.

Changing the PRR from 5,000 pps to 16 pps appears to have had little effect on the rate of resolution, and the response to treatment in the period between tracings 6 and 9, when the PRR of 16 pps was used, was particularly slow. Changing the dosage to 50 J/[cm.sup.2] was followed by the greatest improvement after the initial 11-day period. Increasing the dosage to 50 J/[cm.sup.2] instead of adjusting PRR at the time of tracing 6 might have shortened the overall treatment period.

There appear to be no validated clinical outcome measures for evaluating the size of benign breast lumps. The method of perimeter tracing used in this case derives from the literature on superficial skin wound lesions.[23] The reliability and validity of the method for measuring subcutaneous masses need to be investigated.

A clinical outcome measure is also needed to define the firmness of benign breast lumps. Firmness of breast tissue has been investigated during lactation using a digital tonometer.[30] A 6-point self-rating scale, with the end points "soft, no change" and "very firm and very tender," has also been used.[31] It is not known whether either of these methods used to assess engorgement during lactation would yield valid and reliable measurements of firmness of breast lumps after mammaplasty. Spear and Baker[32] developed a classification system to categorize clinical palpation findings in the diagnosis of capsular contracture of the breast alter augmentation mammaplasty. A class I finding indicates a normal outcome (ie, the surgeon cannot detect the implant during palpation), and a class IV finding indicates an excessively firm and symptomatic breast. A modified Spear and Baker classification system might be useful to define palpation findings in patients with benign breast lumps.

The question arises as to whether the patient's condition would have resolved without LILT. The literature includes reports of patients who were followed tot 5 years after diagnosis of fat necrosis by biopsy.[3,8] Mammograms showed that the lesions did not resolve, although in some instances the fat-fluid level in cysts diminished and the region was replaced by a homogenous dense mass.[8] In this case, the small area of thickened tissue that was present when the patient was discharged had not spontaneously resolved at follow-up after 6 and 12 months, suggesting that improvement ceased when LILT was discontinued. The effectiveness of LILT needs to be confirmed in a randomized controlled trial. Low-intensity laser therapy also could be compared with other modalities used by physical therapists in the treatment of fibrosis and scarring in soft tissue such as ultrasound and phonophoresis.

(*) Sigma-Scan Measurement System, Jandel Scientific, 65 Koch Rd, Corte Madera, CA 94925

References

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[4] Strombeck J. The Strombeck procedure for reduction mammaplasty. In: Goldwyn RM, ed. Reduction Mammaplasty. Boston, Mass: Little, Brown & Co Inc; 1990:131-146.

[5] Bargum K, Nielsen SM. Case report: fat necrosis of the breast appearing as oil cysts with fat-fluid levels. Br J Radiol. 1993;66:718-720.

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[13] Osanai T, Shiroto C, Mikami Y, et al. Measurement of GaAlAs diode laser action on phyagocytic activity of human neutrophils as a possible therapeutic dosimetry, determinant. Laser Therapy. 1990;2:123-133.

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[15] Loevschall H, Arenholt-Bindslev D. Effect of low level diode laser irradiation of human oral mucosa fibroblasts in vitro. Lasers Surg Med. 1994;14:347-354.

[16] Herbert K, Bhusate L, Scott D, et al. Effect of laser light at 820 nm on adenosine nucleotide levels in human lymphocytes. Lasers Life Sci. 1989;3:37-45.

[17] Kiyoizumi T. Low level diode laser treatment for hematomas under grafted skin and its photobiological mechanisms. Keio J Med. 1988;37: 415-428.

[18] Karu T, Tiphlova O, Samokhina M, et al. Effects of near-infrared laser and superluminous diode irradiation on Escherichia coli division rate. IEEE J Quantum Electron. 1990;26:2162-2165.

[19] O'Kane S, Shields T, Gilmore W, Allen J. Low intensity laser irradiation inhibits tritiated thymidine incorporation in the hemopoietic cell lines HL-60 and U937. Lasers' Surg Med. 1994;14:34-39.

[20] Baxter G. Therapeutic Lasers: Theory, and Practice. London, England: Churchill Livingstone; 1994.

[21] Ohshiro T, Maeda T. Application of 830-nm diode laser LLLT as successful adjunctive therapy of hypertrophic scars and keloids. Laser Therapy. 1992;4:155-168.

[22] Price DD, Bush FM, Long S, Harkins SW. A comparison of pain measurement characteristics of mechanical visual analogue and simple numerical rating scales. Pain. 1994;56:217-226.

[23] Majeske C. Reliability of wound surface area measurements. Phys Ther. 1992;72:138-141.

[24] Peh WCG, Truong NP, Totty WG, Gilula LA. Pictorial review: magnetic resonance imaging of benign soft tissue masses of the hand and wrist. Clin Radiol. 1995;50:519-525.

[25] Thorsson O, Lilja B, Nilsson P, Westlin N. Immediate external compression in the management of an acute muscle injury. Scand J Med Sci Sports. 1997;7:182-190.

[26] Ponnudurai RN, Zbuzek VK, Wu W. Hypoalgesic effect of laser photobiostimulation shown by rat tail flick test. Acupunct Electrother Res. 1987:12:93-100.

[27] Mokhtar B, Baxter G, Walsh D, et al. Double-blind, placebo-controlled investigation of the effect of combined phototherapy/low intensity laser therapy upon experimental ischaemic pain in humans. Lasers Surg Med. 1995;17:74-81.

[28] Young S, Bolton P, Dyson M et al. Macrophage responsiveness to light therapy, Lasers Surg Med. 1989;9:497-505.

[29] Bolton P, Young S, Dyson M. Macrophage responsiveness to laser therapy with varying power and energy densities. Laser Therapy. 1991; 3:105-111.

[30] McLachlan Z, Milne E, Lumley J, Walker B. Ultrasound treatment for breast engorgement. Australian Journal of Physiotherapy. 1991;37: 23-29.

[31] Humenick S, Hill P, Anderson M. Breast engorgement: patterns and selected outcomes. J Hum Lact. 1994;10:87-93.

[32] Spear SL, Baker JL Jr. Classification of capsular contracture after prosthetic breast reconstruction. Plast Reconstr Surg. 1995;96: 1119-1123.

EL Nussbaum, PT, is Assistant Professor, Department of Physical Therapy, University of Toronto, and Academic Practice Leader, Mount Sinai Hospital, Toronto, Canada. Address all correspondence to Ms Nussbaum at Department of Physical Therapy, University of Toronto, 256 McCaul St, Toronto, Ontario, Canada M5T 1W5 ([e-mail]).

This article was submitted April 16, 1998, and was accepted March 22, 1999.