• Users Online: 290
  • Home
  • Print this page
  • Email this page
Home About us Editorial board Ahead of print Current issue Search Archives Submit article Instructions Subscribe Contacts Login 


 
 Table of Contents  
ORIGINAL ARTICLE
Year : 2015  |  Volume : 16  |  Issue : 2  |  Page : 97-102

N-butyl-2-cyanoacrylate tissue adhesive versus subcuticular skin closure in external dacryocystorhinostomy


Research Institute of Ophthalmology, Oculoplasty Unit, Ophthalmology Department, Cairo, Egypt

Date of Submission01-Apr-2015
Date of Acceptance10-Jun-2015
Date of Web Publication28-Oct-2015

Correspondence Address:
Dikran G Hovaghimian
Research Institute of Ophthalmology, 17 Roushdy Street, #2 Midan Safir, Heliopolis, Cairo 11361
Egypt
Login to access the Email id

Source of Support: None, Conflict of Interest: None


DOI: 10.4103/1110-9173.165062

Rights and Permissions
  Abstract 

Purpose
The aim of this study was to compare the surgical efficacy and aesthetic outcome of using tissue adhesive N-butyl-2-cyanoacrylate 'Histoacryl' with subcuticular suture closure of skin incision in external dacryocystorhinostomy (DCR).
Design
The present study was conducted as an interventional study.
Patients and methods
A total of 60 chronic dacryocystitis patients undergoing DCR procedures at the Research Institute of Ophthalmology were included. The patients were randomly selected, irrespective of age, sex or race, and were divided into two groups of 30 patients each. A classic external DCR was done for all the patients. At the completion of the surgery, the skin incisions in group 'A' were closed with vicryl 6/0 subcuticular suture, whereas in group 'B' N-butyl-2-cyanoacrylate 'Histoacryl' (FDA approved) tissue adhesive was used to close the skin incisions. No subcutaneous sutures were placed to approximate the wound edges. After 20 s of drying time the adhesive was applied for the second time. All the patients were followed up on the first day, fourth day, first week, second week, first month, and then monthly thereafter for 6 months. The time of suturing the wound and the time of application of the tissue adhesive was recorded for all the patients in both groups. During follow-up the wound was examined for evidence of infection, pain and discharge, and an inquiry was carried out for patient satisfaction. Photographs of the wounds were taken at every visit. The photographs were then shown to a senior surgeon, who was oblivious of the method of closing the wound, and rated the quality of skin incision according to 'WES scale'.
Results
No intraoperative wound complications were encountered in any patient. Statistical analysis of the data available, at 1 month, showed no statistically significant differences between the two groups as regards duration of healing, inflammation or final incision appearance as rated by the senior surgeon. Skin closure time averaged 61 s in subcuticular suture and 52 s in N-butyl-2-cyanoacrylate skin glue, which was statistically insignificant.
Conclusion
Using N-butyl-2-cyanoacrylate glue is an effective and a reliable method for skin closure, yielding similar aesthetic results as skin closure with subcuticular sutures in clean incision for external DCR surgery. It is safe, quick, does not compromise wound integrity, is adequately tolerated by the patients and could be considered an excellent alternative and an improvement on the traditional method of wound closure, providing high level of satisfaction for both patient and surgeon.

Keywords: external dacryocystorhinostomy, Histoacryl, N-butyl-2-cyanoacrylate, subcuticular skin closure


How to cite this article:
Hovaghimian DG, Abou Sedira KA, Farag MY. N-butyl-2-cyanoacrylate tissue adhesive versus subcuticular skin closure in external dacryocystorhinostomy . Delta J Ophthalmol 2015;16:97-102

How to cite this URL:
Hovaghimian DG, Abou Sedira KA, Farag MY. N-butyl-2-cyanoacrylate tissue adhesive versus subcuticular skin closure in external dacryocystorhinostomy . Delta J Ophthalmol [serial online] 2015 [cited 2017 Oct 23];16:97-102. Available from: http://www.djo.eg.net/text.asp?2015/16/2/97/165062


  Introduction Top


External dacryocystorhinostomy (DCR) has been shown to be an effective treatment for nasolacrimal duct obstruction [1] . However, the cutaneous incision made in the medial canthal region may lead to noticeable scarring. Many authors advocate the endonasal approach to avoid the cutaneous incision and many others still prefer the external approach because of familiarity with the procedure, greater operative space and improved surgical visualization [2],[3],[4] . Precise and correct approximation and closure of a skin incision are critical points for a good cosmetic and functional surgical result [4],[5],[6] .

Cyanoacrylates were first synthesized by Ardis [7] . Coover et al. [8] discovered the adhesive properties of cyanoacrylate and suggested their use as surgical adhesives. Since then there has been interest in the use of cyanoacrylate as an alternative to sutures for surgical procedures. Since the 1970s investigators such as Kamer and Joseph [9] and Toriumi et al. [10] reported the use of tissue adhesives for the closure of wounds ranging from blepharoplasty incisions to lid lacerations. Cyanoacrylate adhesives polymerize in an exothermic reaction on contact with a fluid or basic medium to form a strong bond. Shorter chain cyanoacrylates were found to be tissue toxic and the longer chain - for example, N-2-butyl cyanoacrylate - was less/or not tissue toxic, and was thus believed to be an ideal tissue adhesive [9],[10],[11],[12] . Advantages of tissue adhesives include quick application, excellent cosmetic results, patient preference and cost-benefit effectiveness [13],[14] .

This study was designed to compare the surgical efficacy and cosmetic outcome of tissue adhesive 'N-butyl-2-cyanoacrylate' 'Histoacryl' with subcuticular skin closure of the skin incision in external DCR.


  Patients and methods Top


The cohort included 60 patients attending the Research Institute of Ophthalmology clinic. The patients were randomly divided into two groups of 30 patients each: group 'A' in which the skin incisions would be closed with subcuticular skin sutures, and group 'B' in which incisions would be closed with tissue adhesive. The inclusion criteria were patients who were scheduled to undergo external DCR surgery. Exclusion criteria were patients with lacrimal abscess, fistula and previously failed DCR surgery. After obtaining approval from the ethics committee, explanation of the procedure, expected cosmetic outcome and precautions to be taken after surgery was explained to all the patients, and an informed consent was taken from all of them. The two groups of patients were operated upon with classic external DCR through a 1-1.5 cm linear skin incision positioned in the medial canthal region. At the end of the surgery the wounds in the patients of the group 'A' were closed with 6/0 polyglycolic acid (Vicryl) subcuticular suture [Figure 1], whereas in patients in group 'B', after closure of the muscle layer, no subcutaneous sutures were placed to approximate the wound edges. The skin was cleaned for traces of blood and debris and dried thoroughly with gauze to guard against early polymerization of the glue touching the wet surface. The edges of the wounds were held together with tooth-forceps so that the wounds could nicely approximate. Redrying of the wounds was carried out and then N-butyl-2-cyanoacrylate (Histoacryl or Histoacryl blue) [Figure 2] was applied either as a continuous strip method, gently spreading the glue along the entire length of the wound, or as beads intermittently along the edge of the wound [Figure 3] and [Figure 4]. The wounds were held together for 20 s to allow for polymerization and bond formation of the glue to achieve skin closure, and then a second layer was applied overlapping the first layer and extending for a few millimeters away from the wound.
Figure 1: Subcuticular closure of wound of two patients with vicryl 6/0 (courtesy of the authors)

Click here to view
Figure 2: N-Butyl-2-cyanoacrylate Histoacryl and Histoacryl blue (single patient use topical skin adhesive – courtesy of the authors)

Click here to view
Figure 3: Application of N-butyl-2-cyanoacrylate (transparent) on the woundcontinuous method. Upper two photos OD, lower two photos OS before and after application (courtesy of the authors)

Click here to view
Figure 4: Application of Histoacryl blue on the wound as beads (courtesy of the authors)

Click here to view


A dry dressing was applied for patients in group 'A', whereas no dressings were used for those in group 'B'. As a routine a prophylactic postoperative antibiotic was prescribed for all patients in both the groups. The dressing was removed the following day of surgery during the follow-up while the tissue adhesive was left to peel off spontaneously within 7-14 days [Figure 5] and [Figure 6]. The time of suture placement or application time for Histoacryl were recorded for all the patients in both the groups. All the patients were followed up on the first day, fourth day, first week, second week and 1 month, and then monthly thereafter for 6 months.
Figure 5: Histoacryl blue 7 days after surgery. The polymerized Histoacryl starting to fragment (courtesy of the authors)

Click here to view
Figure 6: (a) Histoacryl 1 day after surgery, (b) 1 week after surgery, (c) 1 month after surgery (courtesy of the authors)

Click here to view


The patients in group 'B' were given several instructions to optimize wound healing and prevent infection, which may ultimately compromise the final appearance of the wound.

Patient's instructions included:

  1. Avoid contact with water for the first 24 h and minimize contact with water for the next 7-10 days.
  2. Showering or bathing is permitted but only with transient wetting of the treatment site.
  3. The site should not be soaked or exposed to prolonged wetness until the polymerized film has peeled off.
  4. Do not apply any medications or creams to the wound.
  5. Never pick, pull or scratch the wound as this may cause the wound to reopen.
  6. A transient mild swelling, pain or redness may occur during wound healing. If these symptoms worsen or persist or the wound edges gap, immediately contact your doctor.


Technical points on how to use N-butyl-2-cyanoacrylate

  1. The applicator tip should not be pressed into the wound as this may cause the adhesive to enter the wound and consequently initiate foreign-body reaction, which prevents normal wound healing or causes dehiscence.
  2. Do not apply the glue unless the wound is perfectly aligned. If the wound edges are misaligned after the first application of adhesive, wipe the glue immediately with dry gauze, realign and reapply the glue.
  3. If adhesive runs-off the surgical area, immediately wipe with dry gauze.
  4. If fingers or forceps adhere together or adhere to the patient, a slight pressure on the patient's skin with gentle rolling allows the fingers or forceps to free from the skin without pulling on the edges of the wound.
According to Histoacryl user guide one layer is sufficient, but we preferred to apply two layers of glue. The adhesive spontaneously peels off within 10-15 days, or earlier if the patient attempts to play or continuously wet the area and vigorously dry the washed area. No topical antibiotics should be applied to the closed wound because this would breaks down the adhesive and causes early peeling. In active children, a bandage may be recommended to prevent them from picking at their wound.

During follow-up, wounds were examined for evidence of infection, pain and discharge, and photographs of the wounds were taken. The first and third month postoperative photographs were shown to a senior surgeon, oblivious of the technique of skin closure, to rate the scars. The senior surgeon used the 'WES scale' for rating scars [Table 1] [15] . It consists of six variables and is graded on a 0- or 1-point scale. A total cosmetic score is derived by the addition of all the scores. A score of 6 is considered optimal, whereas a score of 3-5 suboptimal or acceptable wound, and a grade of 1-3 is an unacceptable wound. The results were statistically analyzed.
Table 1 Wound evaluation scalea

Click here to view



  Results Top


A total of 60 patients participated in the present study, 30 patients in each group. In group 'A' there were 17 males (56.7%) and 13 females (43.3%). The mean age was 30.8 years (range 3-66 years). In group 'B' there were 12 males (40%) and 18 females (60%) with a mean age of 29.5 years ranging between 3 and 68 years [Table 2].
Table 2 Demographics of the patients in the two groups

Click here to view


Out of 60 patients, 51 were available for the 6-month follow-up - 25 patients in group 'A' and 26 patients in group 'B'. Statistical analysis of the available data in both groups revealed no statistically significant differences regarding sex, age and the length of the surgical incision. In both groups no wound infections, dehiscence, infection or hypertrophic scars were reported [Figure 7]. As the surgeons who performed all the procedures were efficient, rating of the wound as 'unacceptable' was not reported by the senior surgeon. In all the patients the appearance of the incision was cosmetically acceptable. Statistical analysis of the scar rating showed insignificant differences ( P ≥ 0.725) between the two groups, although the mean scar rate was in favor of group B. The mean scar rate was 4.0 in group 'A', ranging between 3 and 5, whereas in group 'B' the mean scar rate was 5.5, ranging between 4 and 6.
Figure 7: Skin incision of external dacryocystorhinostomy (DCR) closed with Histoacryl. (a) 5 months postsurgery. (b) 6 months postsurgery (courtesy of the authors)

Click here to view


Patient satisfaction was also assessed. Most of the adult patients in group 'B' were happy with the glue idea and appreciated the lack of painful suture removal. Four females (15.38%) were annoyed with the appearance of the glue 1 week after the operation as it looked like dirty skin (starting to peel off) and were not happy as they were instructed not to touch or clean it and were obliged to wear sunglasses to camouflage the appearance or to stay at home till complete separation. As regards patients with subcuticular closure, most of them (20 out of 25 patients; 80%) were satisfied and happy with the subcuticular skin closure and few (five out of 25; 20%) were wondering why they did not use surgical glue for their wound as other patients.

The mean skin closure time was 61 s (range 48-78 s) for subcuticular and 52 s (range 45-62 s) for N-butyl-2-cyanoacrylate (taking in consideration the time that elapsed between the two applications for dryness of the glue). Skin closure time was statistically insignificantly different ( P ≥ 3.21302); we do believe this insignificance is attributed to the small length of the skin incision (±1.5 cm) in our surgeries besides the time taken for the two applications of the glue [Figure 8]. The cosmetic value and patient satisfaction favors the use of the adhesive. Five patients out of the 26 in group 'B' (19.23%) reported mild itching and irritation after the first week during the process of glue fragmentation and separation, and otherwise the wound was nicely coapted. Group 'A' patients did not report any complain and most of them came in the follow-up with clean and well coapted wounds. Some of them were annoyed by the pain during suture removal.
Figure 8: Mean skin closure time for all patients

Click here to view


We did not compare the effect and the duration of application of a single layer of glue to two layers, as it was beyond our scope. However, after the encouraging results reported in our study, we do believe that one layer will be quite satisfactory.


  Discussion Top


'Never judge the surgeon until you have seen him closing the wound' is a saying attributed to Lord Moynihan. The surgical scar remains the only visible evidence of the surgeon's skill and not infrequently, all of his efforts are judged on its final appearance [16] . The ideal method of surgical wound closure should be safe, easy to perform, rapid, painless and should result in minimal scarring [17] .

For surgeons and patients alike, the idea of a surgical tissue adhesive for skin closure is an attractive alternative to the traditional methods of wound closure. Skin adhesive is being used increasingly in many surgical specialties: in trauma, emergency, pediatric, gynecology and general surgery departments [5],[18],[19],[20],[21],[22],[23] . The medial canthal region is an area notorious for unsightly scar, web formation and bow-tie deformity [24] . Factors that may lead to hypertrophic or hyperpigmented scarring include infection, excessive inflammation, poor wound closure and the use of absorbable sutures. We thought that avoiding the placement of any sutures in the wound and closing the incision with surgical glue could potentially improve the appearance of the external DCR incision.

Cyanoacrylate adhesives have a common chemical structure, but subtle variations in the alkyl group can change the properties of each individual tissue adhesive [Figure 9] [8] . Cyanoacrylates are liquid monomers that can be used after surgery to form a rapid and strong adhesion. This process occurs when they come into contact with anions, such as those found in skin moisture or wound exudate. Therefore, when applied to the edges of a wound a strong bond develops, allowing wound closure [9],[10],[25] .
Figure 9: The chemical structure of cyanoacrylate. (R) Represents the variable alkyl group

Click here to view


Early derivatives of methyl-2-cyanoacrylate (Eastman 910 monomer) and ethyl-2 cyanoacrylate (Krazy glue) produced good bonding, but resulted in histotoxicity giving rise to wound inflammation [26] . Their clinical use was therefore hindered. The histotoxicity was due to the short chain alkyl derivatives, which degraded rapidly into cyanoacetate and formaldehyde. These breakdown products could not be excreted at a sufficient rate to prevent their accumulation locally in the tissues, leading to levels that resulted in inflammation. After the discovery of longer chain alkyl derivatives, it was found that they degraded more slowly and produced less inflammation and became clinically useful [27] . A newer derivative, N-butyl-2-cyanoacrylate (Histoacryl blue), was the first tissue adhesive to be successfully used clinically and to receive FDA approval [7],[8],[27],[28] . They highlighted the virtues of its ease of use, such as patient acceptability, convenience of its application, low complication rates, excellent cosmetic outcome, cost-benefit ratio and sealing wounds in pediatric patients. In addition, it also has many nonaesthetic related benefits - for example, minimizing the number of instruments on the operative field and reducing the potential of needle-prick injuries to surgeons and staff. It exists in two forms: Histoacryl and Histoacryl blue. Both forms are sterile translucent liquids for tissue adhesion. They polymerize in seconds upon being exposed to water or water-containing substances like human tissue. Histoacryl and Histoacryl blue are supplied in 0.5 ml single patient use plastic ampoules.

As regards the cost-benefit ratio we found that the cost of one ampoule of 6/0 vicryl is almost equal to 70% of one ampoule of Histoacryl. Yet, we have to consider the fact that one ampoule of 6/0 vicryl is just enough to close the wound of DCR, and a second ampoule may be used according to the surgeon's abilities, whereas one ampoule of Histoacryl is resterlizable, can be used for over three to four patients, thus the cost could be divided on them. Thus, the cost-benefit ratio is in favour of Histoacryl, although its price is relatively higher than 6/0 vicryl.


  Conclusion Top


Using N-butyl-2-cyanoacrylate glue was found to be an effective and a reliable method of skin closure, yielding cosmetic results similar to skin closure with subcuticular sutures of external DCR surgery. It is safe, quick, does not compromise wound integrity, is adequately tolerated by the patients with no skin necrosis, infection or dehiscence. It is easily applied and could be considered an excellent alternative and an improvement on the traditional method of wound closure. N-Butyl-2-cyanoacrylate wound closure is potentially safer as no needles are used, does not need any wound dressing postoperatively or postoperative removal of stitches, besides it provides high level of satisfaction for both patient and surgeon.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 
  References Top

1.
Tarbet KJ, Custer PL. External dacryocystorhinostomy. Surgical success, patient satisfaction, and economic cost. Ophthalmology 1995; 102:1065-1070.  Back to cited text no. 1
    
2.
McDonogh M, Meiring JH. Endoscopic transnasal dacryocystorhinostomy. J Laryngol Otol 1989; 103:585-587.  Back to cited text no. 2
    
3.
Pearlman SJ, Michalos P, Leib ML, Moazed KT. Translacrimal transnasal laser-assisted dacryocystorhinostomy. Laryngoscope 1997; 107:1362-1365.  Back to cited text no. 3
    
4.
Tsirbas A, Davis G, Wormald PJ. Mechanical endonasal dacryocystorhinostomy versus external dacryocystorhinostomy. Ophthal Plast Reconstr Surg 2004; 20:50-56.  Back to cited text no. 4
    
5.
Greene D, Koch RJ, Goode RL. Efficacy of octyl-2-cyanoacrylate tissue glue in blepharoplasty. A prospective controlled study of wound-healing characteristics. Arch Facial Plast Surg 1999; 1:292-296.  Back to cited text no. 5
    
6.
Taravella MJ, Chang CD. 2-octyl CA medical adhesive in treatment of a corneal perforation. Cornea 2001; 20:220-221.  Back to cited text no. 6
    
7.
Ardis AE. US. Patents No. 2467926 and 2467927. New formulation of 2-octylCA tissue adhesive versus commercially available methods. Am J Surg 1949; 188:307-313.  Back to cited text no. 7
    
8.
Coover HN, Joyner FB, Sheere NH, et al. Chemistry and performance of cyanoacrylate adhesive. J Soc Plast Surg Engl 1959; 15:5-6.  Back to cited text no. 8
    
9.
Kamer FM, Joseph JH. Histoacryl. Its use in aesthetic facial plastic surgery. Arch Otolaryngol Head Neck Surg 1989; 115:193-197.  Back to cited text no. 9
    
10.
Toriumi DM, Raslan WF, Friedman M, Tardy ME. Histotoxicity of cyanoacrylate tissue adhesives. A comparative study. Arch Otolaryngol Head Neck Surg 1990; 116:546-550.  Back to cited text no. 10
    
11.
Quinn JV, Drzewiecki A, Li MM, Stiell IG, Sutcliffe T, Elmslie TJ, Wood WE. A randomized, controlled trial comparing a tissue adhesive with suturing in the repair of pediatric facial lacerations. Ann Emerg Med 1993; 22:1130-1135.  Back to cited text no. 11
    
12.
Osmond MH, Klassen TP, Quinn JV. Economic comparison of a tissue adhesive and suturing in the repair of pediatric facial lacerations. J Pediatr 1995; 126:892-895.  Back to cited text no. 12
    
13.
Galil KA, Schofield ID, Wright GZ. Effect of n-2-butyl cyanoacrylate (histoacryl glue) on the healing of skin wounds. I Can Dent Assoc 1984; 50:565-569.  Back to cited text no. 13
    
14.
Brig BM Nagpal, VSM, Kumar MG, et al. Sutureless closure of operative skin wounds. MJAFI 2004; 60:131-133.  Back to cited text no. 14
    
15.
Hollander JE, Singer AJ, Valentine S, Henry MC. Wound registry: development and validation. Ann Emerg Med 1995; 25:675-685.  Back to cited text no. 15
    
16.
Gillman T, Penn J, Bronks D, Roux M. A re-examination of certain aspects of the histogenesis of the healing of cutaneous wounds; a preliminary report. Br J Surg 1955; 43:141-153.  Back to cited text no. 16
    
17.
Elmasalme FN, Matbouli SA, Zuberi MS. Use of tissue adhesive in the closure of small incisions and lacerations. J Pediatr Surg; 1995; 30:837-838.  Back to cited text no. 17
    
18.
Toriumi DM, O'Grady K, Desai D, et al. Use of octyl-2-CA for skin closure in facial plastic surgery. Plast Reconstr Surg 1998; 102:2209-2219.  Back to cited text no. 18
    
19.
Gennari R, Rotmensz N, Ballardini B, Scevola S, Perego E, Zanini V, Costa A. A prospective, randomized, controlled clinical trial of tissue adhesive (2-octylcyanoacrylate) versus standard wound closure in breast surgery. Surgery 2004; 136:593-599.  Back to cited text no. 19
    
20.
Jallali N, Haji A, Watson CJ. A prospective randomized trial comparing 2-octyl CA to conventional suturing in closure of laparoscopic cholecystectomy incisions. J Laparoendosc Adv Surg Tech 2004; 14:209-211.  Back to cited text no. 20
    
21.
Maartense S, Bemelman WA, Dunker MS, de Lint C, Pierik EG, Busch OR, Gouma DJ. Randomized study of the effectiveness of closing laparoscopic trocar wounds with octylcyanoacrylate, adhesive papertape or poliglecaprone. Br J Surg 2002; 89:1370-1375n.  Back to cited text no. 21
    
22.
Lee KW, Sherwin T, Won DJ. An alternate technique to close neurosurgical incisions using octyl CA tissue adhesive. Pediatr Neurosurg 1999; 31:110-114.  Back to cited text no. 22
    
23.
Wang MY, Levy ML, Mittler MA, et al. A prospective analysis of the use of octyl CA tissue adhesive for wound closure in pediatric neurosurgery. Pediatr Neurosurg 1999; 30:186-188.  Back to cited text no. 23
    
24.
McKinley SH, Yen MT. Octyl-2-cyanoacrylate tissue adhesive in external dacryocystorhinostomy. Ophthal Plast Reconstr Surg 2005; 21:197-200.  Back to cited text no. 24
    
25.
Hollander JE, Singer AJ. Application of tissue adhesives: rapid attainment of proficiency. Stony Brook Octylcyanoacrylate Study Group. Acad Emerg Med 1998; 5:1012-1017.  Back to cited text no. 25
    
26.
Trott AT. Cyanoacrylate tissue adhesives. An advance in wound care. JAMA 1997; 277:1559-1560.  Back to cited text no. 26
    
27.
Penoff J. Skin closures using cyanoacrylate tissue adhesives. Plastic Surgery Educational Foundation DATA Committee. Device and Technique Assessment. Plast Reconstr Surg 1999; 103:730-731.  Back to cited text no. 27
    
28.
Hollander JE, Singer AJ. Laceration management. Ann Emerg Med 1999; 34:356-367.  Back to cited text no. 28
    


    Figures

  [Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5], [Figure 6], [Figure 7], [Figure 8], [Figure 9]
 
 
    Tables

  [Table 1], [Table 2]



 

Top
 
 
  Search
 
Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

 
  In this article
Abstract
Introduction
Patients and methods
Results
Discussion
Conclusion
References
Article Figures
Article Tables

 Article Access Statistics
    Viewed1181    
    Printed16    
    Emailed0    
    PDF Downloaded101    
    Comments [Add]    

Recommend this journal


[TAG2]
[TAG3]
[TAG4]