Particle size in fat graft retention: A review on the impact of harvesting technique in lipofilling surgical outcomes

Figures & data

Figure 1. During the first 3 months of tissue remodeling, adipocytes have 3 different fates depending upon their microenvironment and proximity to the surface of the fat particle. Adipocytes in the outermost layer are able to obtain sufficient nutrients through diffusion and survive. Mature adipocytes within the middle layer are unable to withstand the hypoxic conditions, however stem cells are able to survive and proliferate when blood supply is reestablished. All cells within the core die independent of maturity and eventually undergo cicatrization or form oil cysts.

Table 1. List of review studies (Alphabetical Order)

Author	Year	Harvesting technique(s)	Harvesting Site(s)	Recipient Site(s) (if specified)	Findings
Crawford et al.	2010	Liposuction	Upper and lower Hips	None	Minimizing cellular trauma during harvest leads to higher adipocyte viability
Erdim et al.	2008	6-, 4-, 2-mm liposuction cannulas	Abdominal		Higher number of viable adipocytes occurred with 6-mm cannula.
Fagrell	1996	Core fat grafting, excised fat, and lipoaspirate.	Rabbit model: scapular	Rabbit model: scalp and gluteal region	No statistical difference in percent change of weight at 6 months between excised and core fat graft.
Fisher et al.	2013	Filters (500 and 800 um pore size) were used to collect fat particles of different sizes. Volume retention of grafts was then measured	Flank	Mouse model: Dorsum	Filtered fat correlated with a higher volume retention rate than unfiltered fat.
Gonzalez et al.	2007	3-mm cannula or a 2-mm blunt needle	Rat model: sites not specified	None	More cellular trauma in liposuction group. Higher proliferation in blunt needle group
Guyuron et al.	2007	1-cc syringe aspiration	Abdominal and gluteal region	Facial Region	Compared to en bloc removal, 1-cc aspiration was an effective and predictable technique
Huss and Kratz	2002	5-mm cannula and excised fat	Abdominal and breast	None	cell counts were higher in excised fat than liposuction samples at 120 hours after removal.
Kirkham et al.	2012	5-mm and 3-mm cannulas	Abdominal and flank	Mouse model: flanks	Less cellular trauma and fibrosis in the 5-mm group.
Kononas et al.	1993	Excised fat and liposuction samples	Rabbit model: groin	Rabbit model: ear	Excised fat had higher volume retention and less fibrosis than liposuction.
Lalikos et al.	1997	Excised fat and liposuction	Abdominal	None	No difference in terms of cell damage between liposuction and excising fat.
Leong et al.	2004	2-mm diameter syringe needle and 3-mm Triport cannula.	Abdominal	None	No significant difference in cellular metabolism or differentiation. Each study group yielded viable cells
Nguyen et al.	1990	Excised fat vs. liposuction samples	Rabbit model: groin	Rabbit model: ear and rectus muscle implant	90% of adipocytes are lost during liposuction as opposed to 5% during excision of fat.
Nordstrom et al	1997	"sphagettti" core graft	Abdominal	Not specified	3-mm cannula provides satisfying results using "spaghetti" core grafting technique.
Ozoy et al.	2006	4-, 3-, and 2-mm-diameter cannuals	Abdominal	Not specified	highest viability occurred with 4-mm cannula.
Pu et al.	2005	Excised fat and liposuction	Abdominal	None	No difference in cellular architecture of different groups, but liposuction samples had lower G3PD activity.
Shiffman et al.	2001	Various cannulas, needles, and suction pressures during harvest.	Not specified	None	The only significant finding was that a vacuum pressure of −700 mmHg resulted greater than 10% of the total cells rupturing.
Tonnard et al.	2013	Macro-, micro-, and nanofat grafts	Abdominal	None	Normal architecture in macro and microfat grafts, but very few adipocytes in the nanofat graft technique.

Table 2. Inclusion and exclusion criteria

Inclusion Criteria
Subcutaneous white adipose tissue harvested
Review Articles
Original Studies
Human studies
Prospective comparative studies
Animal studies using human fat
Clinical Trials
Randomized, Controlled Trials
Retrospective studies
Case series
Case Reports
Animal studies (using animal fat)
Exclusion Criteria
Articles concerning visceral adipose tissue
Fat grafting for non-plastic surgery applications
Non-English language literature
Inaccessible in Full Text