Dorsal Augmentation: A Review of Current Graft Options

Dorsal augmentation of the nose has been a key component of rhinoplasty procedures since it was first attempted in the late nineteenth century when sterile paraffin was first used to augment a saddle nose deformity.¹ It was soon realized that dorsal augmentation is a difficult maneuver, requiring technical precision and selection of ideal graft materials. Early materials utilized for nasal augmentation included bird bone, pork cartilage, and cow leather.¹ It wasn’t until Konig first used autogenous cartilage to reconstruct nasal deformities² that modern surgical techniques emerged. Over the past century, a plethora of augmentation strategies and graft materials have emerged, but to this day, dorsal augmentation has remained a challenging area in rhinoplasty.³ Over recent decades, dorsal augmentation graft techniques have been used with increasing frequency as biases favoring reductive rhinoplasty have waned and the tendency for augmentation has grown, particularly in select ethnic rhinoplasties.⁴ Dorsal augmentation was first attempted in reconstructive cases,⁵ correcting intrinsic congenital deformities and those acquired due to infection or trauma.⁶

As time has passed, emphasis has shifted to augmentation for more aesthetic purposes.^5,6 Concurrently, the need for secondary revision rhinoplasties has also risen to correct previous failed attempts due to graft failure or resorption, thus further pushing innovators to identify the ideal graft materials associated with diminished associated morbidity and improved handling characteristics.^7,8 Dorsal grafting procedures can now be categorized as aesthetic versus reconstructive camouflage versus augmentation, or autogenous versus alloplastic, although the lines between these materials are often blurred.⁵

The goal of any dorsal augmentation rhinoplasty is to create a soft, smooth nasal bridge with pleasing dorsal aesthetic lines.⁸ The rate of complications must remain low for any technique to maintain a high level of patient satisfaction.⁴ This requires advanced skill, mastery of multiple techniques, a thorough analysis of the anatomy and goals of each individual patient, and vast knowledge of the different options in grafts and implants.^3,8,9 Most experts in the field will agree that an ideal graft does not exist.^3,4,10,11 This review will examine the various graft materials and implants employed for dorsal nasal augmentation and discuss the advantages and disadvantages of each variety, as well as technical nuances for employing them in practice.

Articles for review were identified through a search of the PubMed database by using the following “dorsal augmentation rhinoplasty,” “liquid rhinoplasty,” and “grafts used in rhinoplasty.” Publication dates ranging from 1957-2022 were included. After the search results were refined based on the relevance of article titles, abstracts were screened for relevance before further review. Due to the lack of prospective randomized studies on the topic, case series and expert opinions were included for consideration. A meta-analysis of pulled data was not attempted. The reference sections from each included article were reviewed to identify additional studies for further analysis, and chapters on dorsal augmentation from two key rhinoplasty textbooks were also reviewed.^12,13

The PubMed search yielded 55 abstracts that were chosen for further review. From these, 38 full manuscripts were chosen for formal review. An additional 30 studies listed as references were identified as relevant for inclusion. Additionally, from review of chapters from 2 rhinoplasty textbooks and their references, an additional 13 manuscripts were included. In total, 81 manuscripts were chosen for formal review. Ultimately, 70 resources in total were included in this analysis.

Facial Analysis

The nasal dorsum is one of the most prominent features of the face. If symmetric and well proportioned, it will blend into the other facial aesthetic units. If it is asymmetric, irregular, or disproportionate to the other facial features, it can be visually striking and deforming.¹⁴ The soft tissue envelope of the nose is thinnest over the rhinion.^6,10; therefore, any irregularity will be visible and may mar the outcome, making dorsal augmentation one of the most complication-prone procedures in rhinoplasty.³ During preoperative planning, the surgeon must use physical examination findings and photographic analysis to appraise the size and length of the nasal bones, assess for pathology (such as a saddle nose, inverted-v deformity, and septal deviation), and calculate the relative projection of the radix, dorsum, and nasal tip with relation to the facial thirds to determine the optimal location for augmentation and the degree of augmentation.^3,6,8,13-15 These calculations should also be used to determine whether structural support is needed to lengthen the nose or increase tip projection. The goal of dorsal augmentation in rhinoplasty is to create a straight nasal dorsum and aesthetic lines so that the nose is appropriately sized to fit the face.

Ethnic Factors in Graft Selection

An important factor to discuss with patients when considering the extent of dorsal augmentation is the normal ethnic variations in facial profiles. Dorsal convexity is more often a concern in Caucasian rhinoplasty, whereas a low-profile nasal dorsum is a more prevalent issue in Asian, black, and Creole ethnicities.^3,6 A patient’s goals should be clarified preoperatively to determine whether a more Westernized appearance of the nose is preferred over preservation of normal ethnic profiles. Interestingly, patients in ethnic populations prone to lesser nasal projection who desire augmentation rhinoplasties have a concurrent deficiency of local graft material for use. As is true with the rest of their nasal anatomy, the quadrangular cartilage of individuals of Asian and African ethnicities are smaller and offer less raw material for augmentation.^16,17 The same conundrum presents itself with augmentation cases in the setting of posttraumatic reconstruction and revision rhinoplasties,^6,9,18 hence the utilization of remote tissue graft harvest sites and alloplastic implants.

Graft Characteristics

Numerous graft options have been introduced for dorsal augmentation rhinoplasty.¹⁹ Whether autografts, allograft, or alloplastic implants are being considered, several key properties must be weighed. Materials must be biocompatible, inert, resistant to resorption, and easily moldable while able to retain constant shape and volume.⁴ Additionally, autografts should exhibit low donor site morbidity, while allografts and alloplasts must be free of infection transmission risk and morbidity due to inflammatory processes or carcinogenic potential.⁴ Other considerations include the risk of migration from the chosen site, ease of removal if needed, and the need to be adequately camouflaged under the patient’s skin.⁴ The ideal graft/implant material must also be readily available in ample amounts and cost effective.^4,6,9 It is essential to emphasize that the ideal material does not currently exist.⁴

There is significant demographic variation in the approach to augmentation rhinoplasty, with western countries trending toward a higher use of autografts while surgeons in eastern countries utilize a high proportion of alloplastic materials.^9,20 In a recent survey done by Malone and Pearlman looking at the practices of dorsal augmentation among members of the American Academy of Facial Plastic and Reconstructive Surgery, it was shown that in primary rhinoplasty, autogenous grafts were the first-line choice in 88% of cases whereas alloplasts were the first choice in 11% of cases.⁹ In the West, autogenous materials are often preferred over alloplastic materials due to the reduced risk of a foreign body reaction, decreased incidence of infection, and decreased incidence of erosion and extrusion of material.^4,21 However, they necessitate experience to harvest and are associated with donor site morbidity as well as increased operative time and cost.^4,9

Septal Cartilage

Most surgeons favor septal cartilage for dorsal augmentation.^7,9,13,22 The main advantage of septal cartilage is that it can be harvested from the same operative field, which greatly decreases morbidity and operating time.^13,22 This can be done through a septal incision during closed or open rhinoplasty techniques.^23,24 In all cases, preserving an adequate dorsal “L-strut” is critical to maintain support for dorsal and tip projection of the nose.^6,24

Over time, techniques have developed to maximize the use of septal cartilage while also improving outcomes. Grafts are often carved as a tapered oval to mimic the normal configuration of the keystone. To limit step-offs, the edge of the graft may be beveled or lightly crushed to soften the profile without compromising graft viability.²² For additional camouflage, cartilage grafts may be covered with a layer of fascia to soften transitions and further augment the dorsum. Added refinements of the technique involve scoring the graft with a midline, longitudinal, partial-thickness incision to help bend it into an inverted V or A-frame confirmation. Parallel, paramedian scoring can create an inverted U confirmation that more accurately recreates dorsal aesthetic lines.²² These techniques can be powerful but are exacting and prone to error. Further augmentation can be achieved by stacking layers of cartilage.¹⁰

Septal cartilage is most often used for minimal to moderate dorsal augmentation. Due to its rigidity and flat, planar geometry, it is easily carved into all other grafts utilized for nasal tip augmentation or reconstruction.²² One limiting factor is the minimal quantity of available septal cartilage.^7,22 Often, patients who present for dorsal augmentation tend to have smaller noses and thus may have less septal cartilage available.³ This predicament is made worse in revision rhinoplasty and traumatic cases when septal cartilage may have already been used or damaged.^6,9,18 Additionally, in some cases, such as a severely deviated septum, graft harvesting can be difficult.²² Overresection of the nasal septum can compromise structural integrity of the nose, and inattention to the integrity of the septal lining can lead to development of septal perforations.^1,24Nonetheless, septal cartilage is still often considered the ideal graft source if there is an adequate amount available.

Auricular Cartilage

In close proximity to the nose lies another readily available cartilage donor site—the ear. Due to its proximity and relative ease of harvesting, it is considered a viable graft choice. Sufficient quantities are nearly always available, especially if harvesting both ears, and the use of auricular cartilage preserves septal cartilage for more suitable applications.²¹ While a secondary donor site is required, the ear can be included in the primary operative field, allowing easy access. Cartilage can be harvested from the conchal bowl through either an anterior or posterior approach.²⁴ The cartilage itself is often similar in width to the nasal dorsum and can produce 3 to 6 mm of augmentation.^3,6,8,21 The handling characteristics of auricular cartilage, however, are not always ideal. Auricular cartilage has a natural curvature, making it difficult to sculpt into the desired shape to achieve an aesthetically pleasing dorsal nasal profile.²¹ It can also be fragile, more elastic, and less rigid, which limits its use as structural support. Auricular cartilage is also seen to develop surface and contour irregularities over time due to its intrinsic memory and predisposition toward resorption, and its fragility can cause it to yield to the forces of scar contraction.^{1,3,6-8,10,12,13,21}

Various authors disagree on the significance of the risk associated with auricular donor site morbidity.^6,12,21 Secondary ear deformities should be rare, but excessive harvesting can lead to decreased projection of the pinna and asymmetry.^8,12,21With proper technique, auricular cartilage may yield reliable results for limited dorsal augmentation, but its intrinsically curved geometry may better favor its use in nasal tip grafts, lateral crural strut grafts, or alar margin grafts, preserving other graft materials for the dorsum.

Costal Cartilage

Costal cartilage has gained increased popularity as an option for dorsal augmentation of the nose. Autologous rib cartilage can be harvested from the 5th through 11th ribs, with the 7th rib being the most common.^1,12 The greatest advantage of costal cartilage is its sheer quantity.^{1,3,11,12,25,26} It is the ideal source of cartilage when other donor sites are insufficient, such as in the case of secondary rhinoplasties where septal or auricular cartilage has already been used.^12,25 Costal cartilage opens the doors for surgeons to tackle complex cases^1,3,12 where significant dorsal augmentation (>5 mm^20,27) is needed or structural support for the nose must be re-established. Even when sliced thin, costal cartilage still maintains great strength.¹² Another benefit of costal cartilage is its resistance to resorption.^11,20

The greatest weakness with costal cartilage that limits its universal use is its tendency to warp.¹¹ Wee et al’s meta-analysis showed warping to be the most common local complication, occurring at a rate of 3.08%.²⁶ Warping provides a sense of unpredictability to the use of costal cartilage, and some believe it cannot be prevented.^12,26 In their extensive research into the biomechanics of costal cartilage, Gibson and Davis²⁸ found that there are intrinsic forces at balance within the matrix of costal cartilage; these forces are released once carving is done, leading to warping. There is controversy with regards to the exact time frame of when warping occurs, with many reporting that majority of warping will occur within the first 30 minutes,^1,11,25 but others have stated that warping can occur weeks, months, or any time after surgery.^3,11,25 Numerous approaches to solving this phenomenon have been employed, including the use of specialized carving techniques, such as concentric carving^12,25,28-30; mechanical reinforcement with K wires^1,11,12 and miniplates³¹; various suturing techniques^12,20,32; perichondral fixation to the nasal bone; and sequentially carving the cartilage over several hours to allow the warping pattern to declare itself before final fixation to the nose.^12,25,29 Warping issues have led many surgeons to be hesitant to use costal cartilage; however, many still believe that, with experience and specialized technique, warping can be adequately managed.¹²

Potential donor site morbidity also impacts the usefulness of costal cartilage. Rib harvesting is known to cause contour irregularities, structural defects, and asymmetries of the chest wall,⁶ though less so when a single rib is harvested for rhinoplasty when compared with harvest of the synchondrosis for ear reconstruction. Thoracic scar complications, such as hypertrophy and hyperpigmentation and chest wall pain at the operation site, may occur.^6,7,12,26,27 Care must also be taken to limit cross contamination of the chest wall operative site with respiratory secretions to prevent infection.³³There is small but not insignificant risk of pneumothorax.^6,26,27 With attention to detail, this can be easily managed. Before closing, the operative field should be irrigated and observed for an air leak during a Valsalva maneuver.^33,34 The most common cause of pneumothorax is a small opening in the parietal pleura that can be closed primarily while air is evacuated from the chest with a small catheter.^33,34 Visceral pleural injury and ongoing air leaks necessitating chest tube placement should be exceedingly rare.

Additionally, the increased operative time as well as the postoperative pain from the cartilage harvest puts the patient at increased risk for prolonged hospitalization, infection, atelectasis, and increased financial cost.^4,26 Patients are encouraged to ambulate and perform incentive spirometry and deep breathing exercises to minimize the chance of atelectasis.³⁴ Postoperative pain at the harvest site can be reduced with meticulous surgical technique to minimize dissection, avoid cutting muscle, and leave the free margin of the chest wall intact by harvesting rib 6 or 7.¹² Using multimodal pain modalities, such as bupivacaine liposome injectable suspension, which allows for at least 3 days of pain relief, as well as in situ pain catheters to allow instillation of local anesthetics, have also been found to be effective.^12,34 Using costal cartilage demands a great deal of skill and experience with a steep learning curve in order to properly carve, manage warping, and maintain low postoperative complication rates.^3,6,12,20,26 However, even with all parameters accounted for, the overall complication rates have shown to be relatively low.²⁶

To mitigate the donor site morbidity and problematic warping associated with costal cartilage, focus has shifted to the use of allograft costal cartilage as a possible solution. Allograft costal cartilage has the strength of regular costal cartilage, as well as the benefits of being an allogenic graft: great supply, decreased operating time, and no harvest site morbidity.⁹ Due to robust donor testing and gamma radiation treatment, there is minimal chance of infection transmission, and allograft costal cartilage can be incorporated into the host without host immunologic reactions.^6,8 Since its inception, this material has received mixed reviews, with some surgeons being wary of its risks—namely, resorption, warping, and infection—and long-term prognosis^6,25,35 because initial studies have shown conflicting results.^6,8,27 However, there has been a recent resurgence and confidence in its use.^35,36 A 2020 meta-analysis by Vila et al²⁷was the first paper of its kind to compare the complication rates of autologous versus homologous cartilage from pooled data. A total of 54 studies were included in a systematic review, and 28 retrospective cohort studies were included for the meta-analysis. Mean follow-up periods were 23.2 months (95% confidence interval [CI], 13.8-32.7 months) for autologous costal cartilage studies and 31.2 months (95% CI, 5.4-57.0 months) for allograft costal cartilage. The length of follow-up times in these studies was reassuring as long-term outcomes are most critical in regard to resorption and the longevity of aesthetic results. After analysis, the study demonstrated no difference in outcomes between autologous and allograft cartilage in the near long-term time frame. Personalized informed consent discussions may allow physicians to assess a patient’s preference for an autologous reconstruction method or a desire to avoid donor site necessity.

Diced Cartilage Grafts

The concept of diced cartilage grafts was first pioneered in 1941,¹⁹ although its popularity dwindled until Erol revitalized interest in 2000 with his paper describing his variation of the technique, the “Turkish Delight”—diced cartilage wrapped in Surgicel (Ethicon Inc., Piscataway, NJ).³⁷ Erol’s paper become one of the most cited studies in rhinoplasty literature.³⁸ Although the technique is rarely used today due to lack of reproducibility,¹⁹ it laid the foundation for many popular and effective techniques in current practice.¹ The properties of diced cartilage grafts that make them so intriguing among surgeons are the lack of warping, flexibility in size and shape, postoperative moldability for up to 2 to 3 weeks (allowing for easy in-office alterations without anesthesia), and an excellent ability to camouflage dorsal irregularities and step defects.^{10,12,13,19,20,37} In addition to the handling characteristics of diced cartilage, the techniques are easily reproducible and make use of other pieces of cartilage that may have been discarded otherwise.^3,10,20,39 It has been shown that there is no difference in outcomes when mixed types of cartilage are used (septal/auricular/costal) because dicing the cartilage reduces their biomechanical properties, thus reducing the inert difficulties associated with each type of cartilage while still providing a framework for augmentation.^1,6

The ideal method for employing diced cartilage has been debated. After Erol’s publication,³⁷ there have been myriad developments in the technique, even using diced silicone⁴⁰ and hydroxyapatite.^41,42 Others have attempted, with far different results, to reproduce Erol’s findings. In 2004, Calvert and Daniel¹⁹ found that diced cartilage wrapped in Surgicel failed when the cellulose hemostat induced an inflammatory reaction leading to resorption.^2,19 This complication was mitigated, and greater reliability of graft take was demonstrated, when grafts were wrapped in thin fascia grafts (eg. temporoparietal fascia).^19,43,44 Since then, there have been more proposed modifications in the type of material used to wrap the cartilage, including different types of fascia, acellular dermal matrix, or diced cartilage alone.^3,39

The unpredictability in resorption of diced cartilage grafts can lead to over- and undercorrection.^5,20,37,39 Many surgeons would agree that diced cartilage grafts are not valuable in providing structural nasal support and are limited by the amount of augmentation that they can provide (ideally, less than 4 mm).^{5,10,12,13,19,39} Larger grafts have been shown to be at more risk of migration, of the whole graft or the diced cartilage itself, which can lead to palpable and visual irregularities.^3,5,6,12,19 Furthermore, due to the nature of diced cartilage, some have criticized that the material can lead to “amorphous” aesthetic lines, unlike the more rigid alternatives that produce more exact contours.^10,12 Also, there are reports of dermal scarring that leads to a cobblestone appearance of the overlying skin, especially in thin-skinned patients.^{3,12,19,20,39} Overall, however, diced cartilage does present a viable option for dorsal augmentation, especially when there is a need for camouflage, smooth contours, and moderate amounts of augmentation from 1 to 4 mm.^5,8,39

Bone Grafts

Another option for dorsal augmentation in rhinoplasty is the use of various cortical bone grafts. The three main donor sites are the cranium, rib, and iliac crest.^6,22 In major craniofacial reconstructions, such as those required for traumatic midface injuries and hypertelorism, the cranium represents an ideal donor site as it is immediately adjacent to the operative site, and open access to the nasal radix is available. For isolated rhinoplasty procedures, other donor sites may be considered. Bone provides great strength and structural support and can be useful for more severe nasal deformities when other graft materials are deemed unsatisfactory.^8,9,22 Bone grafts have been shown to yield good long-term results and are well fixed and stable.⁷ On the other hand, the rigid nature of bone makes it difficult to shape,^6,8,9,22 often requiring saws, burrs, and drills intraoperatively; these tools create heat that can kill osteocytes and denature growth factors, leading to graft resorption if careful irrigation is not employed.⁴⁵ Additionally, the rigid nature of bone may lead to suboptimal aesthetic results with unnatural stiff contours and often an uncomfortable, palpable rigidity.^4,6,8 Furthermore, the bone graft must be rigidly fixed to the proximal nasal bones in a cantilever technique. This technique involves rasping the dorsal surface of the proximal nasal bone, then fixation of the proximal portion of a previously carved bone graft onto the rasped surface using k-wires or screws.^46,47 Cantilever grafts may also be at risk of fracture, extrusion, and resorption^4,6-8; clinicians are often dissuaded from using this technique because of  the potential for significant donor site morbidity.^6,7,22,45

Many authors believe that the membranous bone from the cranium is less likely to resorb than endochondral bone from other donor sites, such as the rib and iliac crest.⁸ Additional advantages for cranial bone use are the location of the donor site adjacent to the operative field and the scar position, which can be camouflaged within the hair-bearing scalp.^6,8 The possible complications from cranial bone graft harvesting include donor site alopecia, aesthetic disturbances from full-thickness defects, intracranial hemorrhage, and dural and cerebral injury.^6-8 Split cranial bone grafts may be harvested in situ or by splitting a full-thickness craniotomy segment ex vivo.⁴⁸ Given the potential morbidities associated with the donor site, this graft is likely best employed by surgeons who routinely perform craniofacial reconstructive procedures. This strategy is best suited to midline nasofrontal reconstructions when craniofacial approaches and potential craniotomies are already employed as part of the procedure.

Other donor sites carry their own disadvantages. Iliac crest bone harvesting puts the patient at risk of perioperative ambulatory difficulty, pain, and potentially permanent contour deformity.⁸ Bone grafts harvested from the rib carry the same potential morbidity profile as costal cartilage grafts. Overall, bone grafts are best employed in reconstructive procedures addressing congenital deformities^49-51 or traumatic injuries⁴⁶ where rigid structural support of the nose is needed to stand against a limited soft tissue envelope and there is potential for significant scar contracture.

Soft Tissue Grafts

Soft tissue graft options are often key tools in dorsal augmentation for camouflaging irregularities of the dorsum while providing subtle augmentation.⁹ Fascia has been a useful go-to source for grafting; popular sources are the deep temporal and rectus abdominis fascia, which can be easily harvested during costal cartilage harvesting and thereby limiting operative sites.^5,6 Other common sources include the temporoparietal, mastoid, postauricular, and pectoralis major fascia; the superficial musculoaponeurotic system; the tensor fascia lata; and the pericranium.¹ These grafts have great camouflage abilities to hide minor irregularities, which is useful for patients with thin skin.⁵² Autologous fascia offers increased biocompatibility and carries a low infection rate. Its primary downside is its thinness, which limits dorsal augmentation to 1 to 2 mm and also inhibits its use as a structural graft.^1,5,6,52,53 Depending on the source, there is also the risk of donor site morbidity, such as alopecia with deep temporal fascia.^1,53

Dermal graft use was first documented in 1920,⁵⁴ and the material remains popular to this day. Dermal and dermal fat grafts are the most common autogenous graft materials used in many East Asian countries where they are used following the removal of injected foreign liquid materials into the dorsum, which thins out the dorsal skin.^6,20 The most common donor sites are the abdomen as well as the gluteal area due to its inconspicuous location and dermal thickness.^6,20,54 Like other soft tissue options, dermal grafts are excellent for camouflage and producing a smooth nasal dorsum.^6,20 Like fascial grafts, they are not considered to be very useful for significant augmentation,⁶ but one recent publication reported augmentation capabilities as high as 10 to 12 mm.²⁰ The main downsides of the dermal graft are its immediate contraction after harvest and a marked resorption of 40% to -60%, which can continue for 18 months or longer.^20,54 This mandates that overcorrection of 30% to 40% is necessary, especially with dermal-fat grafts as fat resorbs to a greater extent.²⁰ This degree of variability can prove challenging in rhinoplasty where exact precision is needed to deliver optimal outcomes. Also of note, there are reports of transient swelling, vascular congestion to the site, infections, hematomas, and cyst formation.^20,53

Acellular dermal matrix (ADM) is a homologous soft tissue alternative sourced from cadaver skin, which is processed to remove all cells, bacteria, and viruses, leaving an acellular collagen matrix sheet.^6,8,53 The most common form of ADM is Alloderm (LifeCell, Branchburg, NJ)^9,55 although many types exist. ADM combines the benefits of autogenous tissue: excellent tissue incorporation and host compatibility with no immunologic reaction due to the lack of cells.^8,9,53,55 It also offers the benefits of alloplastic grafts: no donor site morbidity and no restriction on size or amount available. ADM, like other soft tissue options, provides excellent camouflage of irregularities but is limited by resorption and is only capable of minimal dorsal augmentation of approximately 3 mm.^{6,8,9,21,53,55} ADM has waxed and waned in popularity due to cost and theoretical possibility of disease transmission, but it remains a viable option for mild contour abnormalities and dorsal augmentation.⁸

Nonsurgical Rhinoplasty

In recent years, there has been a growing demand for nonsurgical rhinoplasty, also known as “liquid rhinoplasty,” which involves the injection of fillers underneath the soft tissue of the nose.⁵⁶In 2020, rhinoplasty was the most common cosmetic surgical procedures performed in the US, with over 350,000 procedures performed.⁵⁷ Soft tissue filler injections were the second most common minimally invasive cosmetic procedure, with 3.4 million procedures performed. Hyaluronic acid was the most common substance injected in 2.4 million cases.⁵⁷ A proportion of these soft tissue filler injections were performed for the purpose of liquid rhinoplasty. The popularity of this procedure is increasing, though the exact incidence is not currently known. Injection of filling agents allows augmentation of the nasal subunits, with dorsal augmentation being one of the most common indications.^56,58,59

The technique is useful for patients with minor deformities amendable to camouflage, as either a primary procedure or secondary to a previous rhinoplasty. Injections of nasal dorsum can achieve mildly to moderately increased dorsal projection to camouflage dorsal irregularities as a primary concern or to improve an imperfect surgical result. Alternatively, a dorsal hump can be camouflaged by injection of filler material both below and above the hump.⁵⁸

Another recently popularized method of nonsurgical rhinoplasty involves the insertion of polydioxanone threads. These barbed sutures have been used in multiple types of aesthetic procedures of the face.⁶⁰ Typically, the threads are used in non-surgical rhinoplasty procedures to alter tip projection and rotation. Some authors have described their use in conjunction with injectable fillers for nasal augmentation.^61,62 Such procedures take only 15 to 20 minutes, and the threads are also resorbable.⁶¹ These techniques may be ideal for patients who do not want to undergo surgery or are undecided and want to “test” the aesthetic results before undergoing a permanent rhinoplasty.^58,63,64

Nonsurgical rhinoplasty most commonly utilizes hyaluronic acid fillers. Derivatives differ by particle size, molecular weight, and degree of crosslinking. Restylane (Medicis, Scottsdale, AZ) is a popular option due to its high degree of crosslinking, which gives it stability and allows for long-lasting results.^56,63-65 Hyaluronic acid is temporary, but some derivatives have the capability to last up to 12 months.⁵⁹ The procedure is easily reversible with hyaluronidase, which allows surgeons to better limit morbidity compared with that of other options, such as calcium hydroxyapatite, autologous fat grafting, or injectable dermal matrix.^63,64,66,67 Permanent nonautologous fillers are generally avoided due to risk of granulomas and graft migration.^64,67 The growing allure of nonsurgical rhinoplasty can be attributed to several factors: relatively low cost and shorter procedure time compared with surgery, temporary/reversible results, immediate results that can be tailored by the patient and surgeon with mirror feedback, and a shorter recovery time that allows patients to resume normal activities within the same day.^{56,58,59,63,67}

Nonsurgical rhinoplasty requires less technical skill than a surgical rhinoplasty and has a more gradual learning curve, but it comes with its own potential morbidity profile.⁵⁶ Edema and erythema are the most common complications, which usually resolve in a week.^59,67 More significant complications include hypersensitivity or granuloma formation and irregularities from improper injection. The most worrisome outcomes are vascular complications due to direct injury, compression, or cannulation of vessels with subsequent occlusion or embolism of filler material. Vascular complications are rare but can lead to ischemia and subsequent necrosis of the nose or to embolism to the retinal arteries, which can lead to blindness.^59,63,66,67 To limit vascular complications, small aliquots of filler material should be injected with minimal pressure in the midline of the nose, deep to the musculoaponeurotic layers in the avascular perichondral and preperiosteal layers, to avoid injury of vessels. Compression of the dorsal nasal and superior portion of the angular arteries may prevent retrograde flow of filler material into the internal carotid system.^58,59,64,66 Clinicians need to also have ample knowledge and experience with early detection of signs of vascular compromise (eg, pain, skin discoloration, and mottling) and management of complications (eg, hyaluronidase injections, oral aspirin, topical nitroglycerin paste, hyperbaric oxygen, and if needed, early ophthalmology referral).^{56,59,63,64,66,67} Although nonsurgical rhinoplasty is temporary, often requiring repeat procedures, and is also limited by the extent of alterations that can be done, its usefulness and popularity are growing and will continue to have a role as an alternative to surgery.

Alloplastic Implants

Alloplastic implants are becoming more commonly used in both primary and revision rhinoplasty.⁴ The most alluring features of alloplastic implants are ready availability and standardized sizes and shapes with no need for harvesting. This reduces donor site morbidity and procedure time.^4,6,20 Alloplastic implants are also becoming more cost-effective and are available in most countries. Custom grafts can also be made or printed to fit specific size and shapes, making them often easier to use with less of a learning curve compared with that of autogenic materials.^4,6 Nonetheless, alloplastic implants are often not utilized due to their relatively high risk of complications.⁴ They have been associated with an increased risk of infection, foreign body reactions, and extrusion.^{4,12,21,22,25,68} Studies have quoted a risk of infection to be 3.2%⁴ and higher, which has been deemed unacceptable for most surgeons. Additionally, the damage that they can cause to the native tissue can make revision surgeries even more difficult, further limiting their overall use.^3,69

There are currently a wide array of alloplastic implants, the most common being silicone, Gore-tex (W.L.Gore & Associates Flagstaff, AZ), and MedPor (Porex Surgical, College Park, GA).⁷⁰ Each implant material has its own unique properties and carries varying risks of infection, foreign body reaction, extrusion, migration, and resorption. Each implant also provides varying degrees of structural support, augmentation, biointegration, removability, and shaping capability. Although there are ample published reports that advocate for such implants, they have not gained mass popularity in the West.

 This review is intended to provide an overview of the current graft options available for dorsal augmentation. An effort was made to elucidate the rationale for why each graft type is used and their respective advantages and disadvantages. Unfortunately, most of the current literature focuses on retrospective studies done by experts limited to their own experiences. Although expert opinions are very valuable, they carry great risk for publication and recall bias.^18,45 Furthermore, many of the reported complications do not have exact definitions, which limits their comparisons to other studies; for example, “warping” and “aesthetic complications” are based on subjective evaluation and not objective means. Another limitation seen in current literature is the paucity of patient-related data as well as detailed surgical data that delineate each graft’s specific use for each patient. Indications and patient factors vary on a case-by-case basis, thus limiting direct comparisons and generalization.

As seen with Erol³⁷ and Calvert,¹⁹ outcomes may be difficult to duplicate in the hands of others. Furthermore, the length of follow-up time and rates of loss to follow-up limit researchers from painting a panoramic view of the patient outcomes.^4,26 Many complications may only declare themselves after months or years, such as delayed warping and resorption. Additionally, patients who were lost to follow-up may take with them a wealth of knowledge that could have great implications for analysis. Patients who may be dissatisfied with their results may have lost faith in their primary surgeon and consequently may choose not to return for follow-up.⁴ Some researchers have attempted to draw objective conclusions from multiple studies for the purpose of designing prospective studies and for meta-analysis,^26,27,70 but these analyses are limited in number and difficult to produce.

To successfully perform dorsal augmentation for reconstructive and aesthetic rhinoplasty, a surgeon must be facile with various techniques and must be willing to consider multiple treatment options to maximize each patient’s outcome and satisfaction. Surgeons must develop personalized algorithms and constantly critique their outcomes to identify technique limitations and their ability to employ them. In cases of patients who have dorsal irregularities or need minor augmentation, such strategies as liquid rhinoplasty, fascial grafts, or soft tissue products like ADM may be easily employed to smooth the dorsum and offer mild augmentation. In more significant cases of deficient dorsal projection but adequate structural support, diced cartilage grafts wrapped in fascia provide reliable graft techniques to augment the dorsum while remaining forgiving without the risk of warping; diced cartilage grafts also allow for postoperative manipulation to refine imperfections. Finally, in cases with insufficient support for the nose, craniofacial reconstruction of a rigidly fixed nasal skeleton with cantilevered bone grafts are useful. Otherwise, rigidly fixed costochondral rib grafts or carved costal cartilage, combined with a columellar strut, may provide rigid support for the dorsum and tip of the nose. In these difficult reconstructive procedures, potential limitations remain: increased risk of resorption with rigidly fixed bone grafts and warping of carved cartilage grafts.

Current technology allows both autograft and allograft options for cartilage, soft-tissue, and bone grafts. Currently, the literature does not distinguish between the success of these products compared with autologous tissues, but studies will remain hampered by limited long-term outcomes greater than a few months. Subsequently, when local tissues (such as septal cartilage) are insufficient, the decision whether to reach for a product off the shelf or to harvest a remote graft site should rest on a trusting informed consent discussion in which the patient weighs their tolerance for a second operative site versus the potential uncertainty of long-term durability of the result.

Dorsal augmentation in rhinoplasty remains a challenging and exacting art. Various graft materials are described, and each has limitations and benefits. Surgeons must maintain a level of comfort with a large armamentarium of reconstructive modalities; employ a thoughtful, evidence-based algorithm to these clinical challenges; engage patients to better address their desires; and constantly review their results to allow for integral improvement.

Affiliations: Division of Plastic and Reconstructive Surgery, Johns Hopkins All Children’s Hospital; St. Petersburg, FL

Correspondence: S Alex Rottgers, MD; srottge1@jhmi.edu

Disclosures: The authors declare no conflict of interest or financial disclosures.

Ethics: Patients provided written informed consent for use of identifiable images.