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 Table of Contents  
ORIGINAL ARTICLE
Year : 2018  |  Volume : 51  |  Issue : 4  |  Page : 142-147

The use of perforator flaps for the reconstruction of sacral defects: Ten-year experience


1 Department of Surgery, Division of Plastic and Reconstructive Surgery, National Defense Medical Center, Tri-Service General Hospital, Taipei Medical University, Taipei, Taiwan
2 Department of Surgery, Division of Plastic and Reconstructive Surgery, Hyperbaric Oxygen Therapy Center, Shuang-Ho Hospital, Taipei Medical University, Taipei, Taiwan

Date of Submission02-May-2017
Date of Decision05-Jun-2017
Date of Acceptance14-Jan-2018
Date of Web Publication22-Aug-2018

Correspondence Address:
Dr. Chin-Ta Lin
Department of Surgery, Division of Plastic and Reconstructive Surgery, National Defense Medical Center, Tri-Service General Hospital, Taipei
Taiwan
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/fjs.fjs_71_17

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  Abstract 

Background: Despite advances in reconstruction techniques, sacral defects continue to challenge surgeons. The perforator flap preserves the entire contralateral side as a future flap donor site and the gluteal muscle itself on the ipsilateral side to minimize donor-site morbidity.
Materials and Methods: Between April 2003 and March 2013, data obtained from 60 patients with sacral defects reconstructed with perforator flaps were retrospectively analyzed.
Results: We analyzed the sacral defects reconstructed with three different perforator flaps into the following groups: group 1, 30 patients with superior gluteal artery perforator flaps, (average flap size was 83.8 cm2); Group 2, 19 patients with parasacral perforator flaps (average flap size was 94.2 cm2); and Group 3, 11 patients with inferior gluteal artery perforator flaps (average flap size was 85.8 cm2). The overall flap survival rate was 93.3% (56/60).
Conclusion: Perforator flaps are a reliable option for soft-tissue defect reconstruction as they provide a sufficient amount of tissue to cover large sacral defects. We recommend perforator flaps as a viable alternative in the management of sacral defects that cannot be reconstructed with primary closure or local fasciocutaneous flaps.

Keywords: Perforator flap, pressure ulcer, reconstruction, sacral defect


How to cite this article:
Chiao HY, Chang SC, Chou CY, Tzeng YS, Chen SG, Lin CT. The use of perforator flaps for the reconstruction of sacral defects: Ten-year experience. Formos J Surg 2018;51:142-7

How to cite this URL:
Chiao HY, Chang SC, Chou CY, Tzeng YS, Chen SG, Lin CT. The use of perforator flaps for the reconstruction of sacral defects: Ten-year experience. Formos J Surg [serial online] 2018 [cited 2018 Sep 22];51:142-7. Available from: http://www.e-fjs.org/text.asp?2018/51/4/142/239552


  Introduction Top


Managing sacral defects is a common problem for reconstructive surgeons.[1],[2],[3] Typically, gluteus maximus myocutaneous flaps are preferred for managing sacral defects. However, limited shifting capacity, excessive blood loss, and sacrifice of the gluteus maximus muscle are major disadvantages of the procedure.[4],[5],[6]

The perforator flap provides an ample amount of tissue with good vascularity to cover large sacral defects in one stage and does not sacrifice the vascularity or innervation of the underlying gluteus maximus muscle. The aim of this retrospective study was to evaluate the outcomes of perforator flaps for reconstruction of sacral defects.


  Materials and Methods Top


Between April 2003 and March 2013, 60 patients with sacral wounds caused by sacral pressure ulcers or infected pilonidal cysts who underwent surgical reconstruction with perforator flaps were included in this study. We retrospectively analyzed the following groups: group 1, 30 patients (17 men, 13 women; mean age 79.8 [range 22–92] years) whose sacral defects had been reconstructed using superior gluteal artery perforator (SGAP) flaps; Group 2, 19 patients (10 men, 9 women; mean age 62.2 [range 22–89] years) whose sacral defects had been reconstructed using parasacral perforator flaps; and Group 3, 11 patients (8 men, 3 women; mean age 67 [range 44–85] years) whose sacral defects had been reconstructed using inferior gluteal artery perforator (IGAP) flaps.

The causes of sacral defects included pressure ulcers in 56 patients and infected pilonidal cysts in 4 patients. Each ulcer was graded as a Stage IV pressure ulcer, according to the definition developed by Shea.[7] After admission, broad-spectrum antibiotics were prescribed and changed to specific ones if a specific organism was isolated from the wound culture. All patients underwent wound debridement for sacral pressure sores or infected pilonidal cysts. Local wound care was performed using wet-gauze dressing with saline-diluted iodine twice a day to achieve wound bed conditioning. Surgical intervention with a perforator flap was performed electively when the wound bed showed healthy granulation tissue.

In order for the flap harvest to be safer and more time-efficient, we used unidirectional Doppler flowmetry for the preoperative investigation of the gluteal vascular anatomy. Choosing the most suitable perforator from the superior gluteal artery, parasacral area, or the inferior gluteal artery was based on the patient's surgical history and defect location. If the patient received V-Y advancement flap previously, parasacral perforator flap was not suitable due to questionable circulation. If the sacral defect extended over the horizontal line of coccyx, IGAP flap was more suitable for reconstruction.

In the SGAP flaps marking, the patient was positioned in ventral decubitus. The site where the SGA entered the buttock was identified at the junction of the proximal and middle thirds of a line connecting the posterior superior iliac spine (PSIS) to the apex of the greater trochanter of the femur. A line was then drawn between the PSIS and the coccyx. The position of the piriformis was located by joining the middle of the PSIS-coccyx line to the superior edge of the greater trochanter. As the SGA supplied the suprapiriform portion of the gluteus maximus, perforators located cranial to the piriformis and lateral to the SGA exit point would be considered. In the IGAP flaps marking, a line was drawn from the PSIS to the outer part of the ischial tuberosity; the junction of its lower third with its middle third marks the point of emergence of the inferior gluteal and its surrounding vessels from the lower part of the greater sciatic foramen. The course of the IGAP vessels is more oblique through the substance of the gluteus maximus muscle than the course of the SGAPs, which tend to travel more directly to the superficial tissue up through the muscle.

The characteristics of patients' age, sex, underlying diseases, flap size, utilization, outcome, and follow-up period were analyzed. Postoperative care such as pressure relief, skin care, and nutrition were provided intensively through the postoperative period. Ideal skin care encompasses cleaning, hydrating, protecting, and replenishing the skin as needed. It could be time intensive and labor intensive, so we educated the patient's caregiver to learn it. Constant low-pressure devices such as static air bed distributed pressure over a large area were set. The air cushion bed was supported by the government policy, so we routinely helped the patient's family for application after discharged. The nutritionist evaluated daily nutrition intake by oral or enteral feeding.

Ethical approval

The study was conducted in accordance with the Declaration of Helsinki and was approved by the local ethics committee of the institute. Informed written consent was obtained from all patients prior to their enrollment in this study.


  Results Top


Of the 60 patients, Group 1 had undergone reconstruction using SGAP flaps; Group 2 had undergone reconstruction using parasacral perforator flaps; and Group 3 had undergone reconstruction using IGAP flaps. In Group 1, none of the patients required conversion to a myocutaneous rotation flap. The flap size ranged between 42 cm2 and 168 cm2. Twenty-five sacral defects (25/30, 83%) healed completely with no further operations to achieve defect coverage. Two flaps (7%) developed partial necrosis, which were finally treated by contralateral V–Y advancement flap coverage. Three minor complications of partial dehiscence of the wound edge (10%) were finally managed using delayed primary closure. No recurrence was observed during the 14.8-month follow-up period (range 3–24 months).

In Group 2, all flaps survived uneventfully, except for one parasacral perforator flap, which failed because of methicillin-resistant Staphylococcus aureus infection. The average flap size was 94.2 cm2 (range 42 cm–192 cm2). The overall flap survival rate was 95% (18/19). The patient with flap necrosis was finally treated with contralateral V–Y advancement flap coverage. There were two minor complications of partial dehiscence of the wound edge. The dehisced wounds were managed using delayed primary closure. The mean follow-up period was 17.3 months.

In Group 3, the average flap size was 85.8 cm2 (range 56–121 cm2). One patient (1/11, 9.1%) suffered a traction injury to the pedicle during the transfer of the flap through the subcutaneous tunnel; the flap was abandoned and immediately converted to a contralateral V–Y advancement flap. The skin between the sacral pressure sore and the donor site was incised for flap transfer in three cases; in eight cases, the flaps were transferred through a subcutaneous tunnel. One wound dehiscence occurred over the donor site, requiring further wound reapproximation. The longest follow-up was 24 months.

All donor site defects were closed primarily. The mean debridement was 2.3 times (range 1–4) with an average hospital stay of 24.9 days (range 12–58 days). No flap surgery-related mortality was found. In addition, there was no recurrence of sacral defects during the follow-up period. The patients' general data and characteristics are listed in [Table 1].
Table 1: Summary of patients with perforator flaps' reconstruction

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Case study

Group 1 (case 8)

A 72-year-old woman with dementia who was bedridden developed a Grade IV sacral pressure sore. After debridement, an 11 cm × 6 cm SGAP flap was designed to cover the defect. The SGAP flap was taken from the zone immediately adjacent to the defect with a tunnel to place the SGAP flap based on the SGAP. The donor site was closed primarily [Figure 1]. The patient remained recurrence free at 3-month follow-up.
Figure 1: (a) A sacral pressure sore located at the midline sacral region. (b) Design of an 11 cm × 6 cm superior gluteal artery perforator flap for sacral pressure sore coverage. (c) The flap was raised on one perforator, which was still encased in its fibrous septum. (d) The postoperative result 3 months after surgery

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Group 2 (case 6)

A 68-year-old man sustained a sacral pressure sore and exposure of the sacrum. The parasacral perforator flap was designed for reconstruction. One perforator was used, and the rotation angle was 180°. After reconstructive surgery, the sacral defect was well covered, and the flap showed positive results at the follow-up visit 2 weeks later [Figure 2].
Figure 2: (a) A 68-year-old man developed a 5 cm × 5 cm sacral pressure sore and the sacrum was exposed. (b) A parasacral perforator (p) flap was designed to cover the sacral defect. One perforator was used without intramuscular dissection. (c) The flap was rotated about 180° to cover the sacral defect. (d) Flap survival and wound healing were excellent 2 weeks later.

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Group 3 (case 7)

A 78-year-old man had been bedridden for a long term due to a previous stroke. Grade IV sacral pressure sore developed 3 months before admission. There was a 12 cm × 12 cm2 defect after debridement. We designed a 12 cm × 7 cm2 flap from the left gluteal crease. During operation, an IGAP flap was raised and transferred to cover the defect. Five-month follow-up showed positive healing and inconspicuous scarring over the natural gluteal crease [Figure 3].
Figure 3: (a) A sacral pressure sore located at the midline sacral region. (b) Design of a 12 cm × 7 cm inferior gluteal artery perforator flap for sacral pressure sore coverage. (c) The flap was transferred through a subcutaneous tunnel and was inset into the defect. (d) The postoperative result 3 months after surgery

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  Discussion Top


The common causes of sacral defects include pressure ulcers in paraplegic patients and infected pilonidal cysts in ambulatory patients. Delayed wound coverage of a sacral defect can cause progressive infections and wound pain. Surgical debridement and subsequent wound reconstruction remain the best treatments for most patients with a sacral defect.[8],[9] However, operative treatment is often delayed until the patient is optimized and risk factors are corrected. If the patient with severe comorbidities which cannot be easily corrected, chronic wound care may be preferable to attempted reconstruction that is doomed to failure and recurrence. Several types of flaps have been developed to cover sacral pressure ulcers.[10],[11] The gluteus maximus myocutaneous flap has been the most popular technique for closure of a sacral defect due to its reliability and ease of application for surgeons. However, this flap has several shortcomings, such as a bulky appearance, limited distance of flap transposition, and unnecessary blood loss when splitting the muscle.[4],[5],[6] An additional problem is that, in some instances, the suture line of bilateral gluteus maximus myocutaneous flaps lies exactly at the maximal pressure point, resulting in frequent wound dehiscence during recovery.

In 1993, Koshima et al.[12] found 20–25 perforators supplying the entire gluteal region and used gluteal perforator flaps to cover sacral pressure sores. Coskunfirat and Ozgentaş[13] have described the largest case series in literature with 32 gluteal artery perforator flaps for pressure ulcer reconstruction. This perforator-based fasciocutaneous flap has been widely utilized for covering sacral defects because of its advantages of reliability, muscle preservation, low blood loss, and durability.[14],[15]

Verpaele et al.[16] described the use of the SGAP flap, based on the perforator arising from the superior gluteal artery that penetrates the gluteus maximus muscle, to reconstruct a large midline sacral defect. According to an anatomical study by Ahmadzadeh et al.,[17] a mean of 5 ± 2 cutaneous perforators arising from the superior gluteal artery can be found in the gluteal area. All these perforators are myocutaneous, passing through the gluteus maximus muscle or the gluteus medius muscle. The diameter of the superior gluteal perforators ranges from 0.6 to 1.0 mm.[17] The mean size of the SGAP flaps in our series was 42–192 cm2, and the maximum flap size supplied by one SGAP could reach 12 cm × 14 cm.

Deeply dissecting the superior gluteal perforator vessel from the muscle should obtain a pedicle length of 8.5–10 cm, giving the flap an impressive mobility and the possibility of covering large defects with a unilateral flap.[16] A long pedicle can be raised if a lateral perforator is chosen. This provides the flap with a large arc of movement, which allows undamaged tissue to be used from a distant nontraumatized zone in certain cases. In small defects, the surgeons included the perforator vessels in the central portion of the flap design, and the flap was transposed through the undermined tunnel into the defect from the flap donor site. However, in some very large defects, the margins of the defect need to be included in the flap and the flap was inset by rotation.

Parasacral perforators can arise from the lateral sacral artery or the internal pudendal artery, and the diameter ranges from 0.8 to 1.5 mm.[12],[17] The average size of the parasacral perforator flaps in our series was 94.2 cm2 (range 42–192 cm2), and the largest flap nourished by one parasacral perforator measured 16 cm × 12 cm2. Parasacral perforator flaps have benefits in repairing sacral defects, as they can provide fasciocutaneous coverage on the sacral area with gluteal muscle sparing. The circulation of perforator-based flaps is strong, and the flaps are reliable.[13],[17] They are always designed within the proximity of the sacral defects and can be elevated and transposed to the defects in a propeller fashion.

However, the parasacral perforator flap has several limitations. Because the parasacral perforator is near to the wound and its vascular pedicle is short, the rotation arc of the parasacral perforator flap cannot be as long as it of the SGAP flap. The second risk of the parasacral perforator flap is that a propeller transposition of the flap might induce pedicle twisting and potential flap congestion and loss. Demir et al.[18] showed that the twisting angle must not exceed 180° if perforator twisting is to be avoided. In the present study, the average rotation angle of the parasacral perforator flaps was 150° (range 75°–180°) and the maximum rotation angle was 180°. There was no flap congestion or failure caused by pedicle twisting. Another restriction of the parasacral perforator flap is that it may be inadequate in covering an extremely large sacral defect.

Creating the IGAP flap involves dissection of the perforator penetrating the gluteus maximus muscle underneath the piriformis muscle. By separating the dissected pedicle for an island flap, the defect site can be replaced without any tension on the flap. Using the flap from the gluteal crease has several advantages.[19],[20],[21] First, the constant circulation ensures successful flap harvesting from the gluteal crease despite having only tiny (<1–2 mm) perforators.[13] Second, the IGAP flaps minimize donor-site morbidity by sparing the gluteal muscle and providing primary closure of the donor site, leaving a scar that avoids maximal pressure zones over bony prominences and allowing the scar to remain well hidden in the natural gluteal crease.[22] Vascular variation is the major disadvantage of this flap. According to a large case series (n = 118),[23] the descending branch of the inferior gluteal artery is present with variable prevalence.[22],[23] Windhofer et al.[23] reported that the descending branch was present in 91.5% of patients. When the descending branch was absent, the cutaneous branch came from the medial or lateral circumflex femoral artery or as a perforator of the deep artery of the thigh.

Using the gluteal perforator flap is controversial because published anatomical studies state that the blood supply to the gluteal skin is inadequate. Ahmadzadeh et al.[17] performed a detailed dissection of the gluteal region and determined that the vascular territory of a single perforator from the inferior gluteal artery is approximately 24 cm2. However, Koshima et al.[12] demonstrated that a flap in the gluteal region can be nourished even by a single perforator; similarly, Nojima et al.[24] reported that a mean 15 cm × 12 cm2 vascular territory in the SGAP flap can be nourished using a single perforator with the dye injection method. Skin in the gluteal region has also been demonstrated to be richly vascularized with perforators connected by long and voluminous subcutaneous anastomoses.[24] In light of these factors, we have concluded that the determinant factor for flap size is whether the donor site can be primarily closed.

However, there are several limitations in our study. First, perforator flaps are relatively technique demanding and need meticulous dissection to achieve a positive surgical result. They are not preferred by most surgeons. Second, the major defect of this study is the small case number. Third, the patient who has previous surgical scar near the site of perforators is not suitable for perforator flap reconstruction. Algorithm for managing patients with sacral defects in this study was set as [Table 2]. In order to preserve the possibility of another perforator flap or myocutaneous flap reconstruction in the future, we performed perforator flap reconstruction in the patients with paraplegia or bedridden in the study.
Table 2: Algorithm for managing patients with sacral defects

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Sacral defect management is challenging, and the flaps for reconstruction must be carefully selected. Perforator flaps provide good reliability and a sufficient amount of tissue to cover large sacral defects. Other advantages included minimal blood loss, relatively less donor-site morbidity, and preservation of the ability to perform future gluteus maximus myocutaneous flap reconstruction if the defect recurs. Similar to other perforator flaps, pedicle dissection must be meticulous to avoid damaging the perforator vessels. We recommend perforator flaps as a good alternative in the management of sacral defects that cannot be reconstructed with primary closure or a local fasciocutaneous flap.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form the patient(s) has/have given his/her/their consent for his/her/their images and other clinical information to be reported in the journal. The patients understand that their names and initials will not be published and due efforts will be made to conceal their identity, but anonymity cannot be guaranteed.

Acknowledgment

This work was supported by the Civilian Administration Division of Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan (TSGH-C106-165).

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
  References Top

1.
Ohjimi H, Ogata K, Setsu Y, Haraga I. Modification of the gluteus maximus V-Y advancement flap for sacral ulcers: The gluteal fasciocutaneous flap method. Plast Reconstr Surg 1996;98:1247-52.  Back to cited text no. 1
    
2.
Wong CH, Tan BK, Song C. The perforator-sparing buttock rotation flap for coverage of pressure sores. Plast Reconstr Surg 2007;119:1259-66.  Back to cited text no. 2
    
3.
Balakrishnan C, Brotherston TM. Transverse lumbar flap for sacral bed sores. Plast Reconstr Surg 1992;89:998-9.  Back to cited text no. 3
    
4.
Minami RT, Mills R, Pardoe R. Gluteus maximus myocutaneous flaps for repair of pressure sores. Plast Reconstr Surg 1977;60:242-9.  Back to cited text no. 4
    
5.
Parry SW, Mathes SJ. Bilateral gluteus maximus myocutaneous advancement flaps: Sacral coverage for ambulatory patients. Ann Plast Surg 1982;8:443-5.  Back to cited text no. 5
    
6.
Stevenson TR, Pollock RA, Rohrich RJ, VanderKolk CA. The gluteus maximus musculocutaneous island flap: Refinements in design and application. Plast Reconstr Surg 1987;79:761-8.  Back to cited text no. 6
    
7.
Shea JD. Pressure sores: Classification and management. Clin Orthop Relat Res 1975;112:89-100.  Back to cited text no. 7
    
8.
Kierney PC, Engrav LH, Isik FF, Esselman PC, Cardenas DD, Rand RP, et al. Results of 268 pressure sores in 158 patients managed jointly by plastic surgery and rehabilitation medicine. Plast Reconstr Surg 1998;102:765-72.  Back to cited text no. 8
    
9.
Acartürk TO, Parsak CK, Sakman G, Demircan O. Superior gluteal artery perforator flap in the reconstruction of pilonidal sinus. J Plast Reconstr Aesthet Surg 2010;63:133-9.  Back to cited text no. 9
    
10.
Heywood AJ, Quaba AA. Modified gluteus maximus V-Y advancement flaps. Br J Plast Surg 1989;42:263-5.  Back to cited text no. 10
    
11.
Lee HB, Kim SW, Lew DH, Shin KS. Unilateral multilayered musculocutaneous V-Y advancement flap for the treatment of pressure sore. Plast Reconstr Surg 1997;100:340-5.  Back to cited text no. 11
    
12.
Koshima I, Moriguchi T, Soeda S, Kawata S, Ohta S, Ikeda A, et al. The gluteal perforator-based flap for repair of sacral pressure sores. Plast Reconstr Surg 1993;91:678-83.  Back to cited text no. 12
    
13.
Coşkunfirat OK, Ozgentaş HE. Gluteal perforator flaps for coverage of pressure sores at various locations. Plast Reconstr Surg 2004;113:2012-7.  Back to cited text no. 13
    
14.
Roche NA, Van Landuyt K, Blondeel PN, Matton G, Monstrey SJ. The use of pedicled perforator flaps for reconstruction of lumbosacral defects. Ann Plast Surg 2000;45:7-14.  Back to cited text no. 14
    
15.
Meltem C, Esra C, Hasan F, Ali D. The gluteal perforator-based flap in repair of pressure sores. Br J Plast Surg 2004;57:342-7.  Back to cited text no. 15
    
16.
Verpaele AM, Blondeel PN, Van Landuyt K, Tonnard PL, Decordier B, Monstrey SJ, et al. The superior gluteal artery perforator flap: An additional tool in the treatment of sacral pressure sores. Br J Plast Surg 1999;52:385-91.  Back to cited text no. 16
    
17.
Ahmadzadeh R, Bergeron L, Tang M, Morris SF. The superior and inferior gluteal artery perforator flaps. Plast Reconstr Surg 2007;120:1551-6.  Back to cited text no. 17
    
18.
Demir A, Acar M, Yldz L, Karacalar A. The effect of twisting on perforator flap viability: An experimental study in rats. Ann Plast Surg 2006;56:186-9.  Back to cited text no. 18
    
19.
Beshlian KM, Paige KT. Inferior gluteal artery perforator flap breast reconstruction. Am J Surg 2008;195:651-3.  Back to cited text no. 19
    
20.
Allen RJ, Levine JL, Granzow JW. The in-the-crease inferior gluteal artery perforator flap for breast reconstruction. Plast Reconstr Surg 2006;118:333-9.  Back to cited text no. 20
    
21.
Hurwitz DJ. Closure of a large defect of the pelvic cavity by an extended compound myocutaneous flap based on the inferior gluteal artery. Br J Plast Surg 1980;33:256-61.  Back to cited text no. 21
    
22.
Scheufler O, Farhadi J, Kovach SJ, Kukies S, Pierer G, Levin LS, et al. Anatomical basis and clinical application of the infragluteal perforator flap. Plast Reconstr Surg 2006;118:1389-400.  Back to cited text no. 22
    
23.
Windhofer C, Brenner E, Moriggl B, Papp C. Relationship between the descending branch of the inferior gluteal artery and the posterior femoral cutaneous nerve applicable to flap surgery. Surg Radiol Anat 2002;24:253-7.  Back to cited text no. 23
    
24.
Nojima K, Brown SA, Acikel C, Arbique G, Ozturk S, Chao J, et al. Defining vascular supply and territory of thinned perforator flaps: Part I. Anterolateral thigh perforator flap. Plast Reconstr Surg 2005;116:182-93.  Back to cited text no. 24
    


    Figures

  [Figure 1], [Figure 2], [Figure 3]
 
 
    Tables

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