Mr Geoffrey Mullan provides an overview of cryolipolysis for body contouring and presents a case study of a successful treatment
Patients’ desire to improve their silhouette has led to a demand for treatments that improve the body’s contours. There is also a desire to improve the laxity and/or tone of the skin,1,2 reduce lymphoedema, and alter the appearance of cellulite.3 It is important to note that the most popular treatments to contour the body are directed at removing deposits of adipocytes.4,5
Surgical approaches to target the body’s fat are invasive treatments that involve breaching the skin or excision of the skin with the subcutaneous fat, such as in abdominoplasty. Liposuction has long been regarded as an effective way to remove fat from the face and body, and was reported to be the most popular cosmetic surgical treatment in the US in 2016.4,5
However, nowadays a large group of patients seek treatments that are less invasive, with low recovery time, so may wish to receive non-invasive treatments instead. Numerous non-surgical devices work on various levels, and target fat removal, skin tightening and lymphatic massage.
These devices utilise many modalities such as: low power laser,6 radiofrequency,1,2 high-intensity focused ultrasound,7 mechanical vacuum massage to improve lymphatic drainage along with the appearance of cellulite,3 and more recently, cryolipolysis.8,9
In my opinion, body contouring treatments should not be aimed at weight loss but, rather, the correction of asymmetries or areas of lipodystrophy that are stubborn to shift, to attain an improvement of the silhouette in individuals with a healthy body mass index (BMI).
For the purpose of this article, I shall be focusing on body contouring using cryolipolysis.
Controlled cold lipolysis (cryolipolysis) is used for the breakdown of adipocytes by immediate and delayed-induced apoptosis. The technology utilises localised cooling, to extract heat from adipocytes8 and is generally accepted as an effective and safe non-surgical procedure for reducing subcutaneous fat.
Practitioners have performed the procedure on various body regions, such as the abdomen, flanks, inner thighs, outer thighs, and submental areas. Most commonly treated are the flanks and abdomen, and some practices now safely treat both during a single visit.10
Literature has reviewed the effectiveness of cryolipolysis technology. A retrospective study by Dierick et al reviewed 518 patients (73% female, 27% male with a mean age of 42.7 and 22.6). The majority of subjects had Fitzpatrick skin types II (n=200, 38%) and III (n=207, 40%). There were no subjects with Fitzpatrick skin type I, 78 with type IV (15%), and 33 with types V and VI (6%). There were 891 total areas treated, comprising the flanks (59%), abdomen (28%), back (12%), inner thighs and knees (1%), and buttocks (1%). The majority of sites were treated once (86.5%), although some areas were treated two (13%) or three (0.5%) times. The authors reported that 86% showed improvement, 73% were satisfied and only six were dissatisfied after initial treatment, which dropped to two (0.4%) after a second treatment.11
The exact mechanism is a combination of immediate fat cell apoptosis with gradual apoptosis associated with lipid-ice crystallisation, inflammatory panniculitis and a phagocytic process that continues for up to 12 weeks.12,13 One study by Preciado et al used thermo-electric cooling plates on Yucatan pigs to cool the skin’s tissue to -7°C and thermocouple probes to measure the adipose tissue temperature.
It demonstrated that the adipose tissue dropped to 9.5-13.5°C during treatment. As fat cells are more susceptible to cold than other types of tissues,13 controlled cold exposure of adipocytes induces apoptosis with minor effects on surrounding structures.8
Other factors suggest the formation of intracellular ‘lipid ice’, that forms at +10°C (compared to water ice at 0°C), may contribute to the death or delayed apoptosis of fat cells. It may also affect a number of cellular mechanisms, reducing adenosine triphosphate (ATP) levels and Na-K-ATPase enzyme activity, which leads to intracellular lactic acidosis.12
However, it’s not just freezing that can destroy the cells, but the process of warming up the tissues can also have an effect.
Warming cooled adipose tissue through massage – detailed below – after cryolipolysis may promote additional injury to the adipocytes by ischaemia reperfusion (tissue damage caused when blood supply returns to tissue), similar to the reperfusion of cooled transplanted organer enhance the result.14,15
There are a number of cryolipolysis devices available, such as CoolSculpting, MOCOOL-A and 3d-lipo, which also utilise radiofrequency and ultrasound. However, my experience lies with the CoolSculpting device so I will be discussing this in more detail.
After careful assessment, the area to be treated is marked out and a thin cotton gel-impregnated pad is placed on the skin to protect it from direct contact with the cold plates and to work as a conducting agent in removing heat from the skin.
The device utilises vacuum-pressure applicators that draw skin and adipose tissue into an applicator cup, which are specific to the part of the area being treated. If multiple devices are available, more than one area can be treated simultaneously. These ‘cups’ have thermistors and thermo-electric skin level correlates to a temperature drop down to 7-10°C in the fat layer, and blood flow is reduced via tissue compression and cold-induced vasoconstriction.
For this particular device, the temperature reduction is automated and the practitioner does not have any control over the cooling settings, which removes the risk of accidental burns. The device has thermistors that constantly measure the skin temperature and it is believed that the skin is cooled to -5°C during the 60-minute period and this duration avoids frostbite. The company does not actually reveal the exact temperature at which their devices are set.16
The treatment usually lasts for 30-60 minutes per area. This is followed by vigorous tissue massage when the applicator is removed, before moving on to the next region to be treated, which may take a further 30-60 minutes.
Treatments can be performed on the same day and a single treatment is performed per area. Tissue culture research has suggested that adipocytes cooled to below 7°C demonstrate necrotic injury, so practitioners may ask, ‘Will low temperatures not burn the skin or cause necrotic damage?’
However, although the outer periphery skin is being cooled by cooling plates at -5°C, over the course of an hour the inner fat tissue does not reach such low levels and, as long as adipocytes are kept above this ‘therapeutic window’, it is possible to attain the breakdown of fat cells whilst avoiding tissue necrosis and the inflammatory response that this entails. Adipose tissue cooled to 14°C, 21°C, and 28°C result in no necrotic injury, but had the same degree of apoptotic injury as those cooled to 7°C after 48 hours.8
Like any treatment that destroys fat cells, the results are permanent if a stable weight is maintained. For example, in a longitudinal case study, long-term durability was demonstrated in two male patients, who were followed up over a five-year period after the unilateral treatment of one flank.
The untreated flank acted as a control for fluctuations in weight. Although both sides increased in size when weight was gained, the difference in the two sides remained. The increase in the treated size was still demonstrably smaller.17
During the post-treatment phase, the treated area remains numb for seven to 14 days. A search of the literature does not bring up any reported cases where sensation has not recovered nor is there any evidence of any lasting damage on any of the peripheral nerves.19
Common side effects are temporary erythema and minor bruising.
The most common complaint reported is late-onset pain, occurring two week’s post procedure, which generally resolves without intervention.11
As the process involves selective apoptosis leading to the breakdown of adipocytes, there has understandably been concerns that this may affect lipid and triglyceride levels, especially as many clinics now treat multiple areas simultaneously, or in sequence, on the same day. However, a study of 40 patients with fat bulges in their flanks by Coleman et al showed that in the post-treatment period, levels were not affected.21
Cryolipolysis has a low incidence of serious adverse effects, however 33 cases of paradoxical adipose hyperplasia (PAH), have been reported22 and practitioners should discuss this whilst obtaining informed consent as it is a serious potential complication.
In paradoxical hyperplasia, the adipose tissue at the treatment site is reported to increase in mass to a degree that is clearly visible and is a permanent change that does not resolve on its own. It requires further intervention such as liposuction lipectomy to treat the reactive tissue. The cause of PAH is still speculative and is also seen in other lipolysis interventions such as injection lipolysis.22
Practitioners should be aware of copycat cryolipolysis devices. There has been a well-documented case in the press of a severe skin burn performed by a device in a hairdressing salon in Liverpool.23
It is assumed that the device did not cool the skin in a safe way – either the heat extraction was too fast or the cooling plates continued to extract, even when the optimum temperature was attained, and did not cut out when this critical temperature was reached. The earlier named manufacturers were very clear that it was not one of their devices and an online search will show many overseas companies offering fat-freezing devices that do not have safety approvals.
A 37-year-old mother of three, the youngest being 12 months, presented at our clinic with growing frustration that, despite leading a healthy lifestyle, she was struggling with her ‘muffin top’ stomach. The patient claimed that she exercised three to four times a week, and since her third child had not been able to lose fat in the lower abdomen region and flanks. She had a BMI of 25.
In the consultation, we discussed both surgical and non-surgical options, and she decided that, given her busy work and family schedule, she did not want the downtime associated with surgery. Furthermore, the thought of wearing a compression garment for more than two weeks was out of the question.Figure 1: The 37-year-old patient before cryolipolysis treatment.
On examination, she had fat in the lower abdomen but minimal fat in the upper abdomen. There was no ptotic skin or skin aprons, skin quality and elasticity were good and there were no extended stretch marks or muscle diastasis.
There was no marked visceral fat, however the small fat pockets did affect her silhouette when in tighter clothing. Due to the localised fat pockets and good skin quality, a treatment plan was discussed and agreed upon.
We agreed to the treat the lower abdomen on each side and to treat the upper and lower flanks using cryolipolysis. This meant a total of six treatment cycles in one session, each cycle took one hour with a ten-minute break between treatments. The total treatment time including a lunch break took eight hours; although, we often split long treatments into two sessions, depending on the patient’s choice. The treatment was performed at our clinic and the patient had no medical contraindications to cryolipolysis.
As most of the patient’s fat was superficial subcutaneous fat, it was straightforward to treat the area with minimal risk of leaving uneven skin contours. This is due to the homogenous way that the heat is extracted, avoiding the risk that can be left when liposuction is performed too superficially.18
The cryolipolysis treatment device used was CoolSculpting. CoolCore applicators were also used on the lower abdomen, and CoolCurve Plus was used on each flank. The varying applicator cups are shaped in different ways to allow for the contours of the body and therefore maintain a constant vacuum to hold the tissue in place. The device used a mild suction to draw the tissue in to the applicator, where thermoelectric cooling cells extracted heat for 60 minutes per application, and thermistors registered the skin temperature.
At the end of the treatment, a pneumatic massage was delivered using the device and, when the tissue was removed from the applicator cup, a deep tissue massage was performed for five minutes by an aesthetician to speed up the rate of tissue warmth. Sasaki et al demonstrated an increase of 21% in fat reduction in treatments that used post-massage compared to a control.
One hypothesis for potentially improved efficacy with manual massage is that manual massage causes an additional mechanism of damage to the targeted adipose tissue immediately after treatment, perhaps from tissue-reperfusion injury.14 All the patient’s treatments were performed on the same day and the skin erythema returned to a normal colour within 15 minutes.
Her recovery followed a normal pattern of numb skin for eight days, that fully recovered, and slight swelling on the treatment area. Her follow-up was organised for 14 weeks post-procedure (Figure 2) where I observed a significant reduction in the lower abdomen, and the flanks were significantly improved. The patient was very happy with the results.
Liposuction remains the most popular cosmetic surgical treatment for body sculpting; however, there is a large group of patients who wish to find a less invasive alternative. In my experience cryolipolysis is a suitable, safe option for patients who do not wish to have the risks and downtime associated with surgery and my patients have shown a high level of satisfaction.