Journal of Plastic, Reconstructive & Aesthetic Surgery (2014) 67, 712e720
Improving fat graft survival through preconditioning of the recipient site with microneedling* Billur Sezgin a,*, Selahattin Ozmen b, Hakan Bulam c, Suna Omeroglu d, Seher Yuksel e, Banu Cayci e, Tuncay Peker f a Erzurum Regional Training and Research Hospital, Department of Plastic, Reconstructive and Aesthetic Surgery, Erzurum, Turkey b Gazi University Hospital, Department of Plastic, Reconstructive and Aesthetic Surgery, Ankara, Turkey c Numune Research and Training Hospital, Department of Plastic, Reconstructive and Aesthetic Surgery, Ankara, Turkey d Gazi University Hospital, Department of Histology and Embryology, Ankara, Turkey e Gazi University Hospital, Department of Biochemistry, Ankara, Turkey f Gazi University Hospital, Department of Anatomy, Ankara, Turkey
Received 16 August 2013; accepted 15 January 2014
KEYWORDS Adipose tissue; Fat grafting; Fat graft survival; Micro-needling; Microporation; Percutaneous collagen induction; Preconditioning
Summary Although fat grafts are considered the ideal soft-tissue fillers, the main concern dealing with this technique is not being able to predict long-term graft survival due to high absorption rates. The purpose of this study was to investigate the angiogenic effects of preconditioning the recipient area with micro-needling and to determine its overall impact on fat graft survival. The study consisted of a sham, control and study group. The source of fat was the Wistar albino rat inguinal fat pad while the recipient area was a dorsal subcutaneous pouch. The dorsal area was preconditioned with standard technique micro-needling 1-week prior to fat graft transfer in the study group while the control group did not undergo micro-needling. At the end of 15 weeks, morphological, biochemical, histological and immunohistochemical evaluation was carried out. Fat grafts in the study group had better integrity and a higher level of vascularity compared to the control group. Volume analysis demonstrated higher graft survival in the study group in comparison to the control group. Histomorphometric and immunohistochemical evaluation showed better graft integrity and uniform adipocytes, less fibrosis, less vacuolisation and inflammation and better
*
This study was presented 1) at the 2nd European Association of Plastic Surgeons Research Council Meeting, held in Antalya, Turkey, 22e23 May 2013 and 2) at the 48th European Society for Surgical Research Meeting, held in Istanbul, Turkey, 29 Maye1 June 2013. * Corresponding author. Bilkent 2 Park Sitesi, E1 blok, No: 1 Bilkent, Ankara 06800, Turkey. Tel.: þ90 0312 266 1167. E-mail address: [email protected] (B. Sezgin).
1748-6815/$ - see front matter ª 2014 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.bjps.2014.01.019
Improving fat graft survival with microneedling
713
vascularisation in the study group. Although higher triglyceride concentrations were measured for the study group, the difference between the two groups was statistically insignificant. In conclusion, fat grafting performed in an area preconditioned with micro-needling results in higher graft volume, better integrity and vascularisation and an overall higher graft survival rate. ª 2014 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.
Fat tissue is accepted as an ideal soft-tissue filler as it is biocompatible, non-allergic, non-toxic, easy to obtain, harmonious to the natural texture of skin and soft tissues and usually found in abundant amounts.1,2 Along with these advantages, the main concern faced with fat grafts is their unpredictable long-term survival.3e7 This dilemma has guided several studies in the literature to aim to increase graft survival and prevent resorption.8e13 Even though numerous studies have verified the importance of viable adipocytes during transfer,14 current investigations have also steered towards the importance of the recipient site. Grafts are nourished through diffusion from their surrounding recipient bed until angiogenesis occurs within the graft at days 4e5. Therefore, if the vascular supply of the recipient site is well established, it can be assumed that maintaining the viability of fat cells will be that much more likely.15 Several studies have aimed to increase the vascularity of the recipient bed. These include the administration of different chemical mediators such as vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), erythropoietin, interleukin-8, etc. to the recipient site,15e21 and ischaemic and mechanical preconditioning of the recipient bed.22e24 Although these studies have reported substantial increase in graft take and long-term survival, most of them are quite difficult to adapt to routine clinical applications. Micro-needling was first described by Fernandes in 1997 and is also referred to as ‘microporation’, or ‘percutaneous collagen induction’.25 The basic principle of micro-needling involves rolling a cylindrical tool equipped with microneedles over the skin and creating thousands of microchannels that penetrate through the dermis. These microchannels increase the transdermal penetration of topical agents administered over the skin and also trigger the wound-healing process within the dermis and thereby increase skin quality.25e30 Experimental studies have also demonstrated the effect of micro-needling on increasing skin vascularity,31 but there have been no studies investigating the effect of micro-needling on fat graft survival. In light of these data, we conducted a study to determine the impact of micro-needling as a mechanical preconditioning model on the recipient site and to investigate its effects on fat graft survival.
Material and methods Animal model Following approval of the study protocol by the Ethics Committee for Laboratory Animals of Gazi University
Medical School, 18 Wistar albino rats, each weighing 380 (30) g, were used for this study. The source of fat was determined as the inguinal fat pad, while the recipient site was a subcutaneous pouch in the dorsal area of the rat. The study consisted of three groups: the study (micro-needle) group consisted of six rats that underwent standard technique micro-needling followed by fat grafting; the control group consisted of six rats that received no micro-needling and only underwent fat grafting, while the sham group was comprised of six rats that only had a dorsal subcutaneous pouch lifted and sutured back into place. All animals were kept in cages maintained at standard room temperature and were fed ad libitum.
Micro-needling technique The device used for micro-needling was Deeproller 1.50 mm (Assos Pharmaceuticals, Istanbul, Turkey). This device consists of a cylindrical part, equipped with 192 micro-needles of 1.5-mm length, and a handle (Figure 1). For preconditioning to be effective in the subcutaneous area, full-thickness penetration of the skin was intended. Literature studies report an approximate thickness of 1.2 mm for the rat dorsum; therefore, a 1.5-mm-length needle was used to assure full-thickness skin penetration.32 Micro-needling was carried out only on the right dorsal half of the study group. The procedure was performed 1-week before fat graft transfer. After induction of anaesthesia with intramuscular ketamine HCl at 45 mg kg1 dosage, the right dorsal areas were shaved and the dorsal skin was folded onto a wooden tongue depressor in order to allow standard pressure execution of the device onto the skin. Micro-needling was carried out in a standard manner, consisting of 20 back-andforth rolling movements with standard pressure execution both parallel and perpendicular to the axis of the rat’s dorsum. Following the procedure, minimal petechial bleeding was noted at the area of micro-needling (Figure 2). A frame was drawn with a permanent marker around the area to assist in determining the same site for fat graft placement 1-week later.
Fat graft transfer technique One week after micro-needling of the study group, all rats were anaesthetised with intramuscular ketamine HCl (45 mg kg1). The right groin and right dorsal area of all rats were shaved and sterile conditions were obtained with povidone iodine. The adipofascial fat pad was excised meticulously on the right side. Following the measurement of volume of the grafts using the water displacement technique, a standard 2 4 cm subcutaneous pouch
714
B. Sezgin et al.
Figure 1
The device used for microneedling was Deeproller 1.50 mm (Assos Pharmaceuticals, Istanbul, Turkey).
between the dermis and the underlying muscle was dissected, and the fat grafts were rinsed with saline and placed directly into the pouches. Only a dorsal subcutaneous pouch was dissected and sutured back into place in the sham group.
Collection of specimen and evaluation The study duration was 15 weeks. Two animals that died due to anaesthesia were replaced immediately with the exact same experimental protocol. Following this period, all animals were euthanised and specimens were obtained through longitudinal incisions made over the grafted areas. Grafts were dissected from the surrounding loose connective tissue, and following volume analysis with the water displacement technique, 100 mg of fat tissue was reserved for biochemical evaluation while the remaining specimen was fixed for histological and immunohistochemical evaluation. Light microscopical evaluation was carried out with haematoxylin-and-eosin-stained and oil red O-stained slides. Anti-VEGF (Thermo, LabVision, MI, USA) was used for immunohistochemical evaluation to determine vascularisation within the grafted fat tissue specimens. A histomorphometric analysis was conducted with the evaluation of four histological parameters. These parameters were: adipocyte structure and cellular integrity; presence of cysts and vacuoles; inflammation; and presence of fibrosis. Each parameter was scored on a 0e5 scale in a double-blinded, randomised, semi-quantitative fashion by two authors of the study. The presence of each
parameter was scored as 0 Z none, 1 Z minimal, 2 Z minimal to moderate, 3 Z moderate, 4 Z intense and 5 Z very intense. In order to evaluate angiogenesis within the graft objectively, vascularity was determined by calculation of the capillary index. This was executed by counting the number of vascular structures containing erythrocytes per high power field (hpf) in 20 randomised sections from the centre of the graft. This evaluation was also carried out in a double-blinded and randomised fashion. In light of the results of the histomorphometric analysis and capillary index, three-dimensional modelling of both the study and the control groups was carried out after obtaining histological sections. The computer program used for modelling was Cinema 4D Release 13 (Maxon Computers, Friedrichsdorf, Germany).
Triglyceride measurement The concentration of triglycerides within the grafts was measured after harvesting the specimens from the recipient site. A 100-mg specimen was used for this purpose. All samples were obtained from the cranial portion of the fat graft. The measurements were conducted using an enzymatic kit that works through colorimetric analysis (Triglyceride Colorimetric Assay Kit, Cayman Chemical Company, Ann Arbor, MI, USA). Following the hydrolysis of triglycerides into glycerol and fatty acids, the glycerol was measured with coupled enzymatic reactions catalysed by glycerol kinase, glycerol phosphate oxidase and peroxidase. The absorbances of the resulting samples were then measured at 530e550 nm. Different shades of dark purple were obtained and the intensity of the final colour was proportional to the amount of triglyceride within the specimen.
Statistical analysis
Figure 2 Following the standard microneedling technique of 20 back and forth rolling movements in a perpendicular and parallel axis, erythema and minimal petechial bleeding was observed.
Statistical evaluation was carried out using SPSS for Windows v.15.0. Mean values and standard deviations of all data were calculated. All results are expressed as mean standard deviation. Data analysis was conducted by inter-group comparison of the ranked histological parameters, which was employed with the ManneWhitney U test, a non-parametric test designed to compare independent variables. A p value 0.05). At the end of 15 weeks, the grafted fat tissue was harvested through longitudinal incisions made over the skin overlying the fat grafts. At gross observation, it was noted that the study group had maintained good structural integrity of the fat grafts, and there was notable neovascularisation within the graft in close-up view while fat grafts of the control group had areas of visible resorption and necrosis and less structural integrity (Figures 3 and 4). The volume of the fat grafts was measured with the water displacement technique preoperatively and postoperatively for both groups. The mean fat graft volume of the control group was 0.68 0.16 cc preoperatively and 0.42 0.15 cc at the end of 15 weeks, while the preoperative volume for the study group was 0.65 0.22 cc and postoperative volume was 0.57 0.16 cc. Statistical evaluation of the fat grafts prior to transfer showed no significant difference between the two groups regarding preoperative volume (p > 0.05). Volumetric analysis showed that there was a marked decrease in graft volume at the end of 15 weeks in the control group in comparison to the study group (p < 0.05; Table 1).
Triglyceride evaluation At the end of 15 weeks, 100-mg specimens were reserved from the cranial portion of the grafts to measure
Figure 4 At week 15, homogenous distribution of vascularity can be seen within the study group fat graft at close-up view (photography at X4 magnification).
triglyceride concentrations using a colorimetric technique. The mean triglyceride concentration was 351.2 137.1 mg dl1 for the control group, while this value was 438.5 148.6 mg dl1 for the study group. Although the triglyceride concentration of the microneedled group was higher, statistical analysis revealed that the difference was insignificant (p > 0.05).
Histological evaluation Light microscopical evaluation of the haematoxylineeosinstained slides of the grafts demonstrated good structural integrity and lobulation of the adipocytes in the study group, whereas there were notable areas of necrosis and inflammation in the control group. The histomorphometric analysis revealed that adipocyte structure and cellular integrity was significantly better in the micro-needled
Figure 3 The dissection of the fat grafts at 15 weeks demonstrated higher integrity and vascularity in the study group (A,B) while there was notable resorption and necrotic areas in the control group (C,D).
716 Table 1
B. Sezgin et al.
Control group
Study group
p Value
vascularity in the micro-needled study group, whereas notable fibrosis, structural loss and inflammatory cells are seen within the control group (Figures 8 and 9).
0.68 0.16 0.42 0.15
0.65 0.22 0.57 0.16
0.085
Improving fat graft survival through preconditioning of the recipient site with microneedling* Billur Sezgin a,*, Selahattin Ozmen b, Hakan Bulam c, Suna Omeroglu d, Seher Yuksel e, Banu Cayci e, Tuncay Peker f a Erzurum Regional Training and Research Hospital, Department of Plastic, Reconstructive and Aesthetic Surgery, Erzurum, Turkey b Gazi University Hospital, Department of Plastic, Reconstructive and Aesthetic Surgery, Ankara, Turkey c Numune Research and Training Hospital, Department of Plastic, Reconstructive and Aesthetic Surgery, Ankara, Turkey d Gazi University Hospital, Department of Histology and Embryology, Ankara, Turkey e Gazi University Hospital, Department of Biochemistry, Ankara, Turkey f Gazi University Hospital, Department of Anatomy, Ankara, Turkey
Received 16 August 2013; accepted 15 January 2014
KEYWORDS Adipose tissue; Fat grafting; Fat graft survival; Micro-needling; Microporation; Percutaneous collagen induction; Preconditioning
Summary Although fat grafts are considered the ideal soft-tissue fillers, the main concern dealing with this technique is not being able to predict long-term graft survival due to high absorption rates. The purpose of this study was to investigate the angiogenic effects of preconditioning the recipient area with micro-needling and to determine its overall impact on fat graft survival. The study consisted of a sham, control and study group. The source of fat was the Wistar albino rat inguinal fat pad while the recipient area was a dorsal subcutaneous pouch. The dorsal area was preconditioned with standard technique micro-needling 1-week prior to fat graft transfer in the study group while the control group did not undergo micro-needling. At the end of 15 weeks, morphological, biochemical, histological and immunohistochemical evaluation was carried out. Fat grafts in the study group had better integrity and a higher level of vascularity compared to the control group. Volume analysis demonstrated higher graft survival in the study group in comparison to the control group. Histomorphometric and immunohistochemical evaluation showed better graft integrity and uniform adipocytes, less fibrosis, less vacuolisation and inflammation and better
*
This study was presented 1) at the 2nd European Association of Plastic Surgeons Research Council Meeting, held in Antalya, Turkey, 22e23 May 2013 and 2) at the 48th European Society for Surgical Research Meeting, held in Istanbul, Turkey, 29 Maye1 June 2013. * Corresponding author. Bilkent 2 Park Sitesi, E1 blok, No: 1 Bilkent, Ankara 06800, Turkey. Tel.: þ90 0312 266 1167. E-mail address: [email protected] (B. Sezgin).
1748-6815/$ - see front matter ª 2014 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.bjps.2014.01.019
Improving fat graft survival with microneedling
713
vascularisation in the study group. Although higher triglyceride concentrations were measured for the study group, the difference between the two groups was statistically insignificant. In conclusion, fat grafting performed in an area preconditioned with micro-needling results in higher graft volume, better integrity and vascularisation and an overall higher graft survival rate. ª 2014 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.
Fat tissue is accepted as an ideal soft-tissue filler as it is biocompatible, non-allergic, non-toxic, easy to obtain, harmonious to the natural texture of skin and soft tissues and usually found in abundant amounts.1,2 Along with these advantages, the main concern faced with fat grafts is their unpredictable long-term survival.3e7 This dilemma has guided several studies in the literature to aim to increase graft survival and prevent resorption.8e13 Even though numerous studies have verified the importance of viable adipocytes during transfer,14 current investigations have also steered towards the importance of the recipient site. Grafts are nourished through diffusion from their surrounding recipient bed until angiogenesis occurs within the graft at days 4e5. Therefore, if the vascular supply of the recipient site is well established, it can be assumed that maintaining the viability of fat cells will be that much more likely.15 Several studies have aimed to increase the vascularity of the recipient bed. These include the administration of different chemical mediators such as vascular endothelial growth factor (VEGF), epidermal growth factor (EGF), erythropoietin, interleukin-8, etc. to the recipient site,15e21 and ischaemic and mechanical preconditioning of the recipient bed.22e24 Although these studies have reported substantial increase in graft take and long-term survival, most of them are quite difficult to adapt to routine clinical applications. Micro-needling was first described by Fernandes in 1997 and is also referred to as ‘microporation’, or ‘percutaneous collagen induction’.25 The basic principle of micro-needling involves rolling a cylindrical tool equipped with microneedles over the skin and creating thousands of microchannels that penetrate through the dermis. These microchannels increase the transdermal penetration of topical agents administered over the skin and also trigger the wound-healing process within the dermis and thereby increase skin quality.25e30 Experimental studies have also demonstrated the effect of micro-needling on increasing skin vascularity,31 but there have been no studies investigating the effect of micro-needling on fat graft survival. In light of these data, we conducted a study to determine the impact of micro-needling as a mechanical preconditioning model on the recipient site and to investigate its effects on fat graft survival.
Material and methods Animal model Following approval of the study protocol by the Ethics Committee for Laboratory Animals of Gazi University
Medical School, 18 Wistar albino rats, each weighing 380 (30) g, were used for this study. The source of fat was determined as the inguinal fat pad, while the recipient site was a subcutaneous pouch in the dorsal area of the rat. The study consisted of three groups: the study (micro-needle) group consisted of six rats that underwent standard technique micro-needling followed by fat grafting; the control group consisted of six rats that received no micro-needling and only underwent fat grafting, while the sham group was comprised of six rats that only had a dorsal subcutaneous pouch lifted and sutured back into place. All animals were kept in cages maintained at standard room temperature and were fed ad libitum.
Micro-needling technique The device used for micro-needling was Deeproller 1.50 mm (Assos Pharmaceuticals, Istanbul, Turkey). This device consists of a cylindrical part, equipped with 192 micro-needles of 1.5-mm length, and a handle (Figure 1). For preconditioning to be effective in the subcutaneous area, full-thickness penetration of the skin was intended. Literature studies report an approximate thickness of 1.2 mm for the rat dorsum; therefore, a 1.5-mm-length needle was used to assure full-thickness skin penetration.32 Micro-needling was carried out only on the right dorsal half of the study group. The procedure was performed 1-week before fat graft transfer. After induction of anaesthesia with intramuscular ketamine HCl at 45 mg kg1 dosage, the right dorsal areas were shaved and the dorsal skin was folded onto a wooden tongue depressor in order to allow standard pressure execution of the device onto the skin. Micro-needling was carried out in a standard manner, consisting of 20 back-andforth rolling movements with standard pressure execution both parallel and perpendicular to the axis of the rat’s dorsum. Following the procedure, minimal petechial bleeding was noted at the area of micro-needling (Figure 2). A frame was drawn with a permanent marker around the area to assist in determining the same site for fat graft placement 1-week later.
Fat graft transfer technique One week after micro-needling of the study group, all rats were anaesthetised with intramuscular ketamine HCl (45 mg kg1). The right groin and right dorsal area of all rats were shaved and sterile conditions were obtained with povidone iodine. The adipofascial fat pad was excised meticulously on the right side. Following the measurement of volume of the grafts using the water displacement technique, a standard 2 4 cm subcutaneous pouch
714
B. Sezgin et al.
Figure 1
The device used for microneedling was Deeproller 1.50 mm (Assos Pharmaceuticals, Istanbul, Turkey).
between the dermis and the underlying muscle was dissected, and the fat grafts were rinsed with saline and placed directly into the pouches. Only a dorsal subcutaneous pouch was dissected and sutured back into place in the sham group.
Collection of specimen and evaluation The study duration was 15 weeks. Two animals that died due to anaesthesia were replaced immediately with the exact same experimental protocol. Following this period, all animals were euthanised and specimens were obtained through longitudinal incisions made over the grafted areas. Grafts were dissected from the surrounding loose connective tissue, and following volume analysis with the water displacement technique, 100 mg of fat tissue was reserved for biochemical evaluation while the remaining specimen was fixed for histological and immunohistochemical evaluation. Light microscopical evaluation was carried out with haematoxylin-and-eosin-stained and oil red O-stained slides. Anti-VEGF (Thermo, LabVision, MI, USA) was used for immunohistochemical evaluation to determine vascularisation within the grafted fat tissue specimens. A histomorphometric analysis was conducted with the evaluation of four histological parameters. These parameters were: adipocyte structure and cellular integrity; presence of cysts and vacuoles; inflammation; and presence of fibrosis. Each parameter was scored on a 0e5 scale in a double-blinded, randomised, semi-quantitative fashion by two authors of the study. The presence of each
parameter was scored as 0 Z none, 1 Z minimal, 2 Z minimal to moderate, 3 Z moderate, 4 Z intense and 5 Z very intense. In order to evaluate angiogenesis within the graft objectively, vascularity was determined by calculation of the capillary index. This was executed by counting the number of vascular structures containing erythrocytes per high power field (hpf) in 20 randomised sections from the centre of the graft. This evaluation was also carried out in a double-blinded and randomised fashion. In light of the results of the histomorphometric analysis and capillary index, three-dimensional modelling of both the study and the control groups was carried out after obtaining histological sections. The computer program used for modelling was Cinema 4D Release 13 (Maxon Computers, Friedrichsdorf, Germany).
Triglyceride measurement The concentration of triglycerides within the grafts was measured after harvesting the specimens from the recipient site. A 100-mg specimen was used for this purpose. All samples were obtained from the cranial portion of the fat graft. The measurements were conducted using an enzymatic kit that works through colorimetric analysis (Triglyceride Colorimetric Assay Kit, Cayman Chemical Company, Ann Arbor, MI, USA). Following the hydrolysis of triglycerides into glycerol and fatty acids, the glycerol was measured with coupled enzymatic reactions catalysed by glycerol kinase, glycerol phosphate oxidase and peroxidase. The absorbances of the resulting samples were then measured at 530e550 nm. Different shades of dark purple were obtained and the intensity of the final colour was proportional to the amount of triglyceride within the specimen.
Statistical analysis
Figure 2 Following the standard microneedling technique of 20 back and forth rolling movements in a perpendicular and parallel axis, erythema and minimal petechial bleeding was observed.
Statistical evaluation was carried out using SPSS for Windows v.15.0. Mean values and standard deviations of all data were calculated. All results are expressed as mean standard deviation. Data analysis was conducted by inter-group comparison of the ranked histological parameters, which was employed with the ManneWhitney U test, a non-parametric test designed to compare independent variables. A p value 0.05). At the end of 15 weeks, the grafted fat tissue was harvested through longitudinal incisions made over the skin overlying the fat grafts. At gross observation, it was noted that the study group had maintained good structural integrity of the fat grafts, and there was notable neovascularisation within the graft in close-up view while fat grafts of the control group had areas of visible resorption and necrosis and less structural integrity (Figures 3 and 4). The volume of the fat grafts was measured with the water displacement technique preoperatively and postoperatively for both groups. The mean fat graft volume of the control group was 0.68 0.16 cc preoperatively and 0.42 0.15 cc at the end of 15 weeks, while the preoperative volume for the study group was 0.65 0.22 cc and postoperative volume was 0.57 0.16 cc. Statistical evaluation of the fat grafts prior to transfer showed no significant difference between the two groups regarding preoperative volume (p > 0.05). Volumetric analysis showed that there was a marked decrease in graft volume at the end of 15 weeks in the control group in comparison to the study group (p < 0.05; Table 1).
Triglyceride evaluation At the end of 15 weeks, 100-mg specimens were reserved from the cranial portion of the grafts to measure
Figure 4 At week 15, homogenous distribution of vascularity can be seen within the study group fat graft at close-up view (photography at X4 magnification).
triglyceride concentrations using a colorimetric technique. The mean triglyceride concentration was 351.2 137.1 mg dl1 for the control group, while this value was 438.5 148.6 mg dl1 for the study group. Although the triglyceride concentration of the microneedled group was higher, statistical analysis revealed that the difference was insignificant (p > 0.05).
Histological evaluation Light microscopical evaluation of the haematoxylineeosinstained slides of the grafts demonstrated good structural integrity and lobulation of the adipocytes in the study group, whereas there were notable areas of necrosis and inflammation in the control group. The histomorphometric analysis revealed that adipocyte structure and cellular integrity was significantly better in the micro-needled
Figure 3 The dissection of the fat grafts at 15 weeks demonstrated higher integrity and vascularity in the study group (A,B) while there was notable resorption and necrotic areas in the control group (C,D).
716 Table 1
B. Sezgin et al.
Control group
Study group
p Value
vascularity in the micro-needled study group, whereas notable fibrosis, structural loss and inflammatory cells are seen within the control group (Figures 8 and 9).
0.68 0.16 0.42 0.15
0.65 0.22 0.57 0.16
0.085
