Intraorbital Hyaluronic Acid for Enophthalmos
2008; Elsevier BV; Volume: 115; Issue: 6 Linguagem: Inglês
10.1016/j.ophtha.2008.02.015
ISSN1549-4713
Autores Tópico(s)Ophthalmology and Eye Disorders
ResumoHyaluronic acid is a polysaccharide found in extracellular matrix and is used as a soft tissue filler. We report the use of hyaluronic acid gel (HAG) in orbital volume augmentation in a patient with normal vision and enophthalmos and hypoglobus from an orbital floor fracture.A 61-year-old man was referred with mild left hypoglobus and 3 mm of enophthalmos following surgery for panfacial fractures. The rest of ocular examination was normal. Computed tomography (CT) showed previous bilateral maxillary surgery, previous repair of the left infraorbital rim, left frontozygomatic diastasis, and a left orbital floor fracture. He declined orbital floor surgery and opted for a HAG injection for volume enhancement. This was performed under general anesthesia and 2 mL of HAG (Restylane Sub Q, Q-Med AB, Uppsala, Sweden) was injected as a single bolus into the intraconal space via an inferotemporal transconjunctival approach using a blunt 19-G Southampton cannula (Fig 1; available online at http://aaojournal.org). Postoperatively, color vision and pupillary reactions were monitored for 4 hours. He was prescribed 30 mg of oral prednisolone once daily for 3 days, chloramphenicol drops 4 times daily, and oral slow-release acetazolamide 250 mg twice daily for 5 days on discharge. A CT scan performed 1 week after orbital injection showed the deposition of predominantly intraconal soft tissue attenuation material in the inferolateral quadrant of the orbit posterior to the globe. This was attributed to be the injected bolus of HAG. Clinically, the enophthalmos reduced to 1 mm and no hypoglobus was noted. This remained stable at 6 months. Figures 2A and B are the preinjection and postinjection CT sagittal images, which show the orbital floor fracture and also the deposited bolus of HAG.Figure 2A, Sagittal computed tomography (CT) image of right orbit preinjection. Solid arrow shows orbital floor fracture. B, Sagittal CT image of right orbit following injection. Solid arrow shows predominantly intraconal soft tissue attenuation material in the inferolateral quadrant of the orbit posterior to the globe presumed to be the injected hyaluronic acid.View Large Image Figure ViewerDownload Hi-res image Download (PPT)We report the novel use of HAG injection in the treatment of enophthalmos in a patient with normal vision. We chose Restylane Sub Q because it has the largest particle size (1,000 gel particles per milliliter).Hyaluronic acid gel has a very low risk of allergic reactions and modern formulations, through cross-linking, last between 6 and 12 months. It is hydrophilic and exhibits dynamic viscosity, which makes it suitable as an injectable material. As degradation occurs, more water is bound to the remaining molecules, resulting in longer volume retention effects.1Eppley B.L. Dadvand B. Injectable soft tissue fillers: clinical overview.Plast Reconstr Surg. 2006; 118: 98e-106eCrossref PubMed Google ScholarThe differences between the various preparations lie in the concentration of the HAG, the size of the particles, and the degree of cross-linking. Currently, formulations approved by the US Food and Drug Administration include Restylane, Hylaform, Hylaform Plus, Captique, Juvederm Ultra, and Juvederm Ultra Plus.Other injectable materials used in orbital volume augmentation include autologous fat, collagen, self-inflating hydrogel pellets, and calcium hydroxyapatite gel (Radiesse).2Hunter P.D. Baker S.S. The treatment of enophthalmos by orbital injection of fat autograft.Arch Otolaryngol Head Neck Surg. 1994; 120: 835-839Crossref PubMed Scopus (41) Google Scholar, 3Cahill K.V. Burns J.A. Volume augmentation of the anophthalmic orbit with cross linked collagen (Zyplast).Arch Ophthalmol. 1989; 107: 1684-1686Crossref PubMed Scopus (37) Google Scholar, 4Schittkowski M.P. Guthoff R.F. Injectable self inflating hydrogel pellet expanders for the treatment of orbital volume deficiency in congenital microphthalmos: preliminary results with a new therapeutic approach.Br J Ophthalmol. 2006; 90: 1173-1177Crossref PubMed Scopus (53) Google Scholar, 5Kotlus B.S. Dryden R.M. Correction of anophthalmic enophthalmos with injectable calcium hydroxylapatite (Radiesse).Ophthal Plast Reconstr Surg. 2007; 23: 313-314Crossref PubMed Scopus (18) Google Scholar Autologous fat and non–cross-linked collagen suffer from high resorption rates. Zyplast, a cross-linked collagen, has a more persistent effect and has been used in volume augmentation of anophthalmic orbits.3Cahill K.V. Burns J.A. Volume augmentation of the anophthalmic orbit with cross linked collagen (Zyplast).Arch Ophthalmol. 1989; 107: 1684-1686Crossref PubMed Scopus (37) Google Scholar Self-inflating injectable hydrogel pellets have been used in the treatment of volume deficiency in congenital microphthalmos. However, because high pressures are induced by the expansion process, these pellets are contraindicated in eyes with visual potential.4Schittkowski M.P. Guthoff R.F. Injectable self inflating hydrogel pellet expanders for the treatment of orbital volume deficiency in congenital microphthalmos: preliminary results with a new therapeutic approach.Br J Ophthalmol. 2006; 90: 1173-1177Crossref PubMed Scopus (53) Google Scholar Recently, Radiesse, an injectable suspension of calcium hydroxyapatite particles in a gel carrier, was used successfully in the treatment of traumatic enophthalmos in a normally sighted eye.5Kotlus B.S. Dryden R.M. Correction of anophthalmic enophthalmos with injectable calcium hydroxylapatite (Radiesse).Ophthal Plast Reconstr Surg. 2007; 23: 313-314Crossref PubMed Scopus (18) Google ScholarOur deep intraorbital technique involved the delivery of a single bolus into the intraconal space via an inferotemporal transconjunctival approach using a blunt 19-G Southampton cannula similar to that used for subtenon's anesthesia in cataract surgery.We hypothesize that the deposition of a single bolus created a "lake" of HAG, minimizing the surface area to volume ratio, thereby reducing the rate of resorption. The degree of enophthalmos was reduced by 2 mm with 2 mL of HAG, which would imply that 1 mL of HAG may result in a 1 mm reduction, although this assumption would need to be assessed more formally.We counseled the patient with regard to sight-threatening complications such as globe puncture, intraorbital bleeding, and the theoretical risk of stimulating the oculocardiac reflex during injection owing to extraocular muscle stretch from the HAG settling in an intraconal location. No complications resulted in our patient and he was very satisfied with the cosmetic result at 6 months follow-up. The postoperative medical regimen was probably unnecessary, and we would not routinely use it again.In conclusion, the apparent success and lack of complications in our case suggest that further study into the feasibility of this technique in the treatment of enophthalmos in normally sighted eyes may be warranted. An adequately powered prospective study would be needed to assess formally both success and complication rates. Hyaluronic acid is a polysaccharide found in extracellular matrix and is used as a soft tissue filler. We report the use of hyaluronic acid gel (HAG) in orbital volume augmentation in a patient with normal vision and enophthalmos and hypoglobus from an orbital floor fracture. A 61-year-old man was referred with mild left hypoglobus and 3 mm of enophthalmos following surgery for panfacial fractures. The rest of ocular examination was normal. Computed tomography (CT) showed previous bilateral maxillary surgery, previous repair of the left infraorbital rim, left frontozygomatic diastasis, and a left orbital floor fracture. He declined orbital floor surgery and opted for a HAG injection for volume enhancement. This was performed under general anesthesia and 2 mL of HAG (Restylane Sub Q, Q-Med AB, Uppsala, Sweden) was injected as a single bolus into the intraconal space via an inferotemporal transconjunctival approach using a blunt 19-G Southampton cannula (Fig 1; available online at http://aaojournal.org). Postoperatively, color vision and pupillary reactions were monitored for 4 hours. He was prescribed 30 mg of oral prednisolone once daily for 3 days, chloramphenicol drops 4 times daily, and oral slow-release acetazolamide 250 mg twice daily for 5 days on discharge. A CT scan performed 1 week after orbital injection showed the deposition of predominantly intraconal soft tissue attenuation material in the inferolateral quadrant of the orbit posterior to the globe. This was attributed to be the injected bolus of HAG. Clinically, the enophthalmos reduced to 1 mm and no hypoglobus was noted. This remained stable at 6 months. Figures 2A and B are the preinjection and postinjection CT sagittal images, which show the orbital floor fracture and also the deposited bolus of HAG. We report the novel use of HAG injection in the treatment of enophthalmos in a patient with normal vision. We chose Restylane Sub Q because it has the largest particle size (1,000 gel particles per milliliter). Hyaluronic acid gel has a very low risk of allergic reactions and modern formulations, through cross-linking, last between 6 and 12 months. It is hydrophilic and exhibits dynamic viscosity, which makes it suitable as an injectable material. As degradation occurs, more water is bound to the remaining molecules, resulting in longer volume retention effects.1Eppley B.L. Dadvand B. Injectable soft tissue fillers: clinical overview.Plast Reconstr Surg. 2006; 118: 98e-106eCrossref PubMed Google Scholar The differences between the various preparations lie in the concentration of the HAG, the size of the particles, and the degree of cross-linking. Currently, formulations approved by the US Food and Drug Administration include Restylane, Hylaform, Hylaform Plus, Captique, Juvederm Ultra, and Juvederm Ultra Plus. Other injectable materials used in orbital volume augmentation include autologous fat, collagen, self-inflating hydrogel pellets, and calcium hydroxyapatite gel (Radiesse).2Hunter P.D. Baker S.S. The treatment of enophthalmos by orbital injection of fat autograft.Arch Otolaryngol Head Neck Surg. 1994; 120: 835-839Crossref PubMed Scopus (41) Google Scholar, 3Cahill K.V. Burns J.A. Volume augmentation of the anophthalmic orbit with cross linked collagen (Zyplast).Arch Ophthalmol. 1989; 107: 1684-1686Crossref PubMed Scopus (37) Google Scholar, 4Schittkowski M.P. Guthoff R.F. Injectable self inflating hydrogel pellet expanders for the treatment of orbital volume deficiency in congenital microphthalmos: preliminary results with a new therapeutic approach.Br J Ophthalmol. 2006; 90: 1173-1177Crossref PubMed Scopus (53) Google Scholar, 5Kotlus B.S. Dryden R.M. Correction of anophthalmic enophthalmos with injectable calcium hydroxylapatite (Radiesse).Ophthal Plast Reconstr Surg. 2007; 23: 313-314Crossref PubMed Scopus (18) Google Scholar Autologous fat and non–cross-linked collagen suffer from high resorption rates. Zyplast, a cross-linked collagen, has a more persistent effect and has been used in volume augmentation of anophthalmic orbits.3Cahill K.V. Burns J.A. Volume augmentation of the anophthalmic orbit with cross linked collagen (Zyplast).Arch Ophthalmol. 1989; 107: 1684-1686Crossref PubMed Scopus (37) Google Scholar Self-inflating injectable hydrogel pellets have been used in the treatment of volume deficiency in congenital microphthalmos. However, because high pressures are induced by the expansion process, these pellets are contraindicated in eyes with visual potential.4Schittkowski M.P. Guthoff R.F. Injectable self inflating hydrogel pellet expanders for the treatment of orbital volume deficiency in congenital microphthalmos: preliminary results with a new therapeutic approach.Br J Ophthalmol. 2006; 90: 1173-1177Crossref PubMed Scopus (53) Google Scholar Recently, Radiesse, an injectable suspension of calcium hydroxyapatite particles in a gel carrier, was used successfully in the treatment of traumatic enophthalmos in a normally sighted eye.5Kotlus B.S. Dryden R.M. Correction of anophthalmic enophthalmos with injectable calcium hydroxylapatite (Radiesse).Ophthal Plast Reconstr Surg. 2007; 23: 313-314Crossref PubMed Scopus (18) Google Scholar Our deep intraorbital technique involved the delivery of a single bolus into the intraconal space via an inferotemporal transconjunctival approach using a blunt 19-G Southampton cannula similar to that used for subtenon's anesthesia in cataract surgery. We hypothesize that the deposition of a single bolus created a "lake" of HAG, minimizing the surface area to volume ratio, thereby reducing the rate of resorption. The degree of enophthalmos was reduced by 2 mm with 2 mL of HAG, which would imply that 1 mL of HAG may result in a 1 mm reduction, although this assumption would need to be assessed more formally. We counseled the patient with regard to sight-threatening complications such as globe puncture, intraorbital bleeding, and the theoretical risk of stimulating the oculocardiac reflex during injection owing to extraocular muscle stretch from the HAG settling in an intraconal location. No complications resulted in our patient and he was very satisfied with the cosmetic result at 6 months follow-up. The postoperative medical regimen was probably unnecessary, and we would not routinely use it again. In conclusion, the apparent success and lack of complications in our case suggest that further study into the feasibility of this technique in the treatment of enophthalmos in normally sighted eyes may be warranted. An adequately powered prospective study would be needed to assess formally both success and complication rates.
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