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Balanced orbital decompression in Graves' orbitopathy
Operative Techniques in Otolaryngology (2012) 23, 219-226
ORIGINAL CONTRIBUTION
Balanced orbital decompression in Graves’ orbitopathy Stefano Sellari-Franceschini, MD From The Unit of Otorhinolaryngology, Department of Neuroscience, University of Pisa, Pisa, Italy. KEYWORDS Graves’ orbitopathy; Orbital decompression; Balanced decompression; Diplopia
Graves’ ophthalmopathy is an inflammatory disease of the orbital tissues that especially affects extraocular muscles and fat. Orbital decompression is performed to reverse compressive neuropathy and reduce proptosis. The most widely used technique is the inferomedial orbital decompression, which may provide an insufficient decompression in patients with serious proptosis. A balanced decompression of the medial and lateral orbital walls provides ⬎5 mm of proptosis reduction with a low occurrence of postoperative diplopia. © 2012 Elsevier Inc. All rights reserved.
Graves’ orbitopathy is an autoimmune inflammatory disorder that involves extraocular muscles, intraconal fat, and eyelids, and it is the most common cause of exophthalmos in adulthood. Moreover, the clinical features of the disease may be different depending on the presence and prevalence of edema or fibrosis, and they include eyelid retraction or edema, proptosis, chemosis, diplopia, exposure keratopathy, and optic neuropathy. The reasons for surgery are therefore variable and can be purely cosmetic, due to serious or at least substantial proptosis, with or without diplopia, or due to optic neuropathy. Over the years, different surgical techniques have been proposed. This is because of the multifaceted nature of the disease, the different objectives for decompression, and the range of the surgeon’s skills. During the past few years, in particular, the number of rehabilitative orbital decompression operations has increased1 because the target of surgery is no longer limited to recovering vision and/or reducing proptosis but also reducing the incidence of postoperative diplopia. As far as surgical approach is concerned, there is a general consensus on the fact that the reduction of proptosis is directly correlated to the number of orbital walls removed and that diplopia is the most frequently reported side effect of orbital decompression using bone removal technique.1 Address reprint requests and correspondence: Stefano Sellari-Franceschini, MD, Unit of Otorhinolaryngology, Department of Neuroscience, University of Pisa, Via Paradisa, 2, 56124 Pisa, Italy. E-mail address: [email protected]. 1043-1810/$ -see front matter © 2012 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.otot.2012.04.002
Indeed, the removal of an orbital wall not only causes a rearward movement of the eyeball but also a centrifugal displacement of rectus muscle close to the osteotomy that causes an increased duction in the direction of action of this muscle or decreased duction in the direction of its antagonist.2 Therefore, the removal of the orbital wall close to a restricted rectus muscle can be the main cause of an eye imbalance and consequently of a postoperative new onset or worsening of diplopia. Although all the extrinsic muscles can be involved in the disease, the inferior and medial rectus muscles are involved most frequently and most seriously. Vertical diplopia is even more difficult to correct because vertical fusional reserves are lower than horizontal fusional reserves, so even the smallest vertical deviation angles can cause debilitating diplopia.3 Therefore, a balanced approach to the medial and lateral wall measured in relation to the function of the medial and lateral rectus muscles is the one that in most cases allows to obtain a satisfactory reduction of proptosis with a minor risk of eye imbalance.3-6
Surgical technique This procedure is performed in patients under general anesthesia. The patient is positioned supine on the operating table. The first step in surgery is closing the eye to prevent corneal damage. We normally use an antibiotic ointment and then join
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Operative Techniques in Otolaryngology, Vol 23, No 3, September 2012
Protection of the eye. Nylon stitches are used (A) to close the eyelids (B). (Color version of figure is available online.)
the eyelids with two 5/0 nylon stitches (Figure 1). In patients with serious proptosis is worthwhile not to close the eye to avoid congestion during decompression maneuvers.
Approach to the medial wall The operation starts with an endoscopic ethmoidectomy. The middle turbinate is normally removed to achieve a wider access to the lamina papiracea. Systematic opening of the sphenoidal sinus is useful as a landmark for the ethmoidal roof. Once the lamina papiracea has been skeletonized, a wide middle antrostomy is performed to expose the angle between medial and inferior orbital walls. With a Freer elevator or with a curette the lamina papiracea is fractured, and the posterior part is removed first being careful not to open the periorbita (Figure 2). In few cases, the lamina papiracea is thick, and it is useful to drill it with a diamond burr to thin the bone and make its fracture easier. In other cases, the lamina papiracea is thin and has been pushed sideways by the hypertrophic medial rectus muscle (Figure 3). In these cases, great care should be taken to not accidently open the periorbita while fracturing the papiracea. The fracture point of the lamina papiracea should be planned before the operation. The papiracea is removed by fracturing it from lateral to medial both superiorly and inferiorly, using blunt instruments, such as a Freer elevator or a curette. Based on necessity and considering the efficiency of the medial rectus muscle, the papiracea can be removed more widely in a rearward direction with backbiting forceps, but this maneuver entails more risk of accidentally breaking the periorbita. In fact, during this “bone approach,” it is necessary to be extremely careful to not open the periorbita. The penetration of the fat tissue and of the belly of the medial rectus muscle in the operative field can hinder the complete posterior removal of the lamina papiracea. It is of utmost importance to not remove the anterior because of the risk of closing the nasofrontal recess (Figure 4). The posterior third of the floor can be removed with the aid of a diamond burr (Figure 5). If the bone is thin or after
having drilled it, it can be down-fractured using the elevator or a courette introduced between the periorbita and the orbital floor. At this point, the nasal cavities are temporarily softly packed while performing the lateral orbitotomy; this because it is preferable to open the periorbita after the completion of the bone demolition (lateral and medial).
Approach to the lateral wall The most direct and cosmetically appealing approach is the upper eyelid approach, also called superior blepharoplasty. After having infiltrated the upper eyelid with a solution with vasoconstrictor, the skin is incised along the main skin crease above the upper margin of the tarsal plate (Figure 6).
Figure 2 Removal of the lamina papiracea (asterisk) with a blunt elevator. ER, ethmoidal roof; P, periorbita; SS, sphenoid sinus.
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Figure 3
Balanced Orbital Decompression
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Preoperative CT scan showing enlarged medial rectus muscles that imprint the lamina papiracea.
Ideally, the incision includes the skin and the orbicularis muscle, which are tightly connected (Figure 7A). Thus, it is important not to cut too deeply to avoid lesion to the levator oculi palpebrae muscle. Therefore, it is often worthwhile to perform the incision only in the skin (Figure 7B) followed by dissection through the muscle, lifting the skin. Scissors are first used to spread underneath the orbicularis muscle (Figure 7C), and then to incise it (Figure 7D). Lifting the musculocutaneous flap, the elevation continues laterally until the frontal-zygomatic arch. Careful incision with a blade of the periosteum and lifting it beginning from the orbital frame are at this point of fundamental importance (Figure 8). Retracting the eyeball medially using a malleable elevator, the blunt dissection of the periorbita continues on the external half of the orbital roof, on all the lateral wall, and on the floor.
Figure 4 Removal of the lamina papiracea is limited to its posterior 2⁄3. Anteriorly, it is left intact to prevent the obliteration of the nasofrontal recess. P, Periorbita; ER, ethmoidal roof; pwMS, posterior wall of the maxillary sinus; ON, optic nerve; AEA, anterior etmoidal artery. (Color version of figure is available online.)
It is advisable to perform the elevation of all the periorbita in a 180 degree arc immediately (Figure 9), cauterizing the small vessels coming from the infraorbital canal, the meninx, and the bone (Figure 10). Inserting a silicone sheet (Silatos Silicone Sheeting, Atos Medical, Sweden) (Figure 11A-11C) to protect the periorbita and to prevent the penetration of orbital fat into the operating field makes surgery easier. This allows us to use a smaller malleable retractor for maximum retraction, increasing the surgical field (Figure 11D). At this point, the removal of the bone in the superolateral area is commenced with cutting, and diamond burrs until the dura of the anterior cranial fossa is seen (Figure 12). This is the landmark used to follow medially and posteriorly toward the orbital apex (Figure 13). Then, we move carefully downward until the meninx of the middle cranial fossa is seen. Then, the position of the surgeon changes to allow drilling downward (Figure 14), thinning the zygomatic arch and
Figure 5 Removal of the posterior third part of the orbital floor (medial to the infraorbital nerve) with the aid of a diamond burr. SS, sphenoid sinus; MS, maxillary sinus; ER, etmoidal roof; LP, lamina papiracea.
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Figure 8 A periosteal incision is performed on the superolateral orbital rim to begin the subperiosteal dissection.
Figure 6
Skin incision on the superior eyelid.
the bone that cover the temporalis muscle. It is a good idea not to uncover this muscle too much, as it could be traumatized by the surgical movements and bleed. At this point of the operation, it can be useful to go on to an approach to the lateral tract of the orbital floor, and the orbital floor lateral to the infraorbital nerve is drilled inferiorly. The mucous of the maxillary sinus can be simply uncovered or the sinus itself can be completely opened. At this point, the drilling continues posteriorly and inferiorly removing the residual bone lateral to the inferior orbital fissure. Before proceeding to the following stage, it is important to clean the cavity and check any possible bleeding point to
Figure 7 Incision should be made in a supratarsal skin fold (A, B). To prevent damages to the levator palpebrae muscle (pink), it is necessary to carefully dissect and cut the orbicularis oculi muscle (green) (C, D). (Color version of figure is available online.)
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Balanced Orbital Decompression
Figure 9 The periorbita should be elevated in a 180° arc immediately. (Color version of figure is available online.)
cauterize it, if necessary. Bleeding from the bone can be sealed with a diamond burr.
Opening of the periorbita Once the “bone stage” has been completed, which can be symmetric or asymmetric, depending on the seriousness and degree of the condition, the incision, or rather the removal of the periorbita, is begun. This is the most delicate surgical stage as regards the risk of eyeball deviation. The incisions always begin in the posterior tract of the optical cone because the fat tissue and/or the rectus muscle emerging from an accidental medial anterior opening can cover and interfere with the procedure in the deeper part. In cases of balanced decompression, the opening of the periorbita begins at the level of the lateral wall. With the help of a malleable elevator, sharp scissors are used to penetrate the periorbita at a distance of about 1 cm from the eyeball equator (Figure 15): the scissors are then opened to lacerate the periorbita. At this point, the periorbita behind this incision line is cut in an anterior–posterior direction, until it is completely removed (Figure 16). Then, the same procedure is continued to remove the periorbita, leaving the outermost 5-10 mm to leave support for the muscle pulleys system. It should be borne in mind that, superiorly, V1 lies on the levator palpebrae superioris muscle, thus careful attention must be paid so as not to damage it when working at this level. Following this, the periorbita of the medial wall is opened. The incision begins from the apex in a posterior to anterior direction using a sickle knife (Figure 17). Sparing the anterior third, or half, of the wall to reduce the risk of a postoperative esotropia. At this point, still with the scissors externally and sickle knife through the nasal approach, the fat tissue can be manipulated, breaking the septa between the various sections. Then, by careful cauterization, part of the fat tissue can be removed (Figure 18). It is advisable to remove only the fat tissue of the inferior lateral section (inferiorly to the lateral rectus muscle), as this is safer as far as the possibility
223 of causing postoperative diplopia is concerned. If necessary, to increase the decompression, the fat tissue found above the medial rectus muscle can be moved medially. To this end, it can be helpful to cut it with a sickle knife, helping with light pressure on the eyeball. It is not advisable to perform the same maneuver medially, on the fat tissue inferior to the medial rectus muscle because, despite having a good decompressive effect, it has the disadvantage of a good chance of postoperative esotropia, often not rectifiable intraoperatively. All these actions on the fat tissue should be performed alternatively on each of the 2 eyes, to balance the decompression. Experience has shown that the most involved eye is also the most difficult to decompress, and thus it could be a good practice to begin any maneuver with the worst eye, than balancing the reduction of the proptosis by working on the other. Once the maximum obtainable decompression has been reached, above all on the basis of the patient’s needs, the operation is practically finished. As regards the nasal access, this can be finished without placing swabs or with a small nasal sponge dressing. It is better to insert this into a surgical glove finger to avoid adhesion to the orbital content. Two silicon tubes can be placed in addition to the swabs to improve the next 48 hours of the patient with a minimum of respiratory opening. As regards the translid approach, an intradermal suture with nylon 4/0 will suffice. It can be useful, and also prudent from a legal point of view, to place drainage in the external section of the orbit for 24 hours.
Results A total of 327 patients (638 orbits) were decompressed using this technique between 1998 and 2009, in the ENT Unit of the University of Pisa.
Figure 10 A careful cauterization of the small vessels coming out from the bone to the periorbita is needed during elevation of the periorbita from the bone. (Color version of figure is available online.)
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Figure 11 Positioning a plastic (Silastic) sheet helps in preventing damage to the periorbita. A, Elevation of the periorbita; B, shaping of a Silastic sheet; C, insertion of the Silastic sheet; D, Silastic sheet in position: this allows us to use a smaller malleable retractor for maximum retraction. (Color version of figure is available online.)
Although the medial and lateral walls were approached in all patients, the amount of bone demolition was different in some patients based on the workings of the extrinsic muscles and the amount of proptosis. As regards muscle function, if the medial rectus muscle or, more rarely, the lateral rectus became restricted, a reduction of the opening of the medial or lateral walls was attempted to avoid muscle displacement, with a consequent increase in the deficit of eye motility. As far as the reduction in proptosis was concerned, the amount of osteotomy and opening of the periorbita were varied during the operation so as not to cause enophthalmos, and in bilateral asymmetric cases, to balance the decompression in the 2 eyes.
With this technique and following these surgical principles, the average proptosis reduction was 5.81 ⫾ 2.45 mm (range 0-14 mm) with a 13.2% of postoperative new primary gaze diplopia (patients with a preoperative motility disturbance were excluded during this analysis of postoperative diplopia). We observed 2 intraoperative and 4 major postoperative complications. The first were connected to the endonasal approach: 2 rhino-liquorrea, 1 closed intraoperatively, and 1 closed after 2 days, when it became evident. As regards postoperative complication, we had to operate on 2 patients on the following day for retrobulbar hemorrhage, due to the removal of the drainage accidentally per-
Figure 12 The removal of the lateral orbital wall is made by drilling the bone. (Color version of figure is available online.)
Figure 13 Extent of the lateral bone removal at the end of surgery. (Color version of figure is available online.)
Sellari-Franceschini
Balanced Orbital Decompression
Figure 14
Position of the surgeon while drilling the lateral wall (left) or the orbital floor (right).
formed by the patient. Two other patients demonstrated a visual loss due to compression of the optic nerve, from ethmoidal bone fragments, with a similar need for revision surgery, resulting in a recovery of vision in both cases.
Discussion Graves’ orbitopathy is an inflammatory disease, which mainly affects the fat tissue and the extraocular muscles. After the inflammatory process, the muscles are enlarged, and a result of fibrosis and fact degeneration,1 this muscular dysfunction can cause eye imbalance or lead to postoperative imbalance. Diplopia is, in fact, the most frequent post-
Figure 15
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Opening of the periorbita with sharp scissors.
operative complication. Therefore, it is important to adapt the technique to the needs of the patient, providing a balanced technique. The technique we report is free from disfigurement of the orbital profile. Removing the great sphenoidal wing together with, if necessary, the external part of the roof and the external part of the floor allow the correction obtained with the ethmoidectomy to be better balanced. Lateral bone demolition can be performed by a translid incision, which provides a direct approach to the lateral orbital wall. In addition, the opening of the periorbita and remodeling of the fat medially and laterally permit a progressive reduction and balancing of the proptosis.
Figure 16 periorbita.
Drawing illustrating the first lateral incisions of the
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With this in mind, it can also be useful to remove the fat tissue, and based on both personal experience and the literature7 in the field, it is advisable to remove only the fat tissue of the inferolateral section, as it is safer as far as postoperative diplopia is concerned.
Conclusions Graves’ orbitopathy is a disease that involves the extrinsic muscles of the eye, the retro-orbital fat tissue, and eyelids in an extremely variable manner. All of these structures can be affected in different ways in either one or both eyes. Therefore, there is a great deal of variation in clinical manifestation. Within the particulars, a balanced decompression technique is described that allows a good reduction in proptosis and a reduced possibility of postoperative diplopia through removal of the medial and lateral bone walls.
Figure 18 After the periorbita has been opened, the retrobulbar fat is manipulated and partially removed.
In addition, the opening of the periorbita and removal of fat tissue are dealt with in detail. Furthermore, with this technique, the surgeon is also in a position to tackle both the most serious cases with optic neuropathy and particular cases in which it is important to avoid worsening existing serious eye imbalance, varying the way of approach toward the walls. Drawing on a personal experience of 327 patients operated on using this technique, an analysis of the results is also put forward, and intra- and postoperative complications are also covered.
References
Figure 17 The periorbita is opened transnasally with the aid of a sickle knife.
1. Siracuse-Lee DE, Kazim M: Orbital decompression: current concepts. Curr Opin Ophthalmol 13:310-316, 2002 2. Abràmoff MD, Kalman R, De Graaf MEL, et al: Rectus extraocular muscle paths and decompression surgery for Graves orbitopathy: mechanism of motility disturbances. IOVS 43:300-307, 2002 3. Unal M, Leri F, Konuk O, et al: Balanced orbital decompression combined with fat removal in graves ophthalmology: do we really need to remove the third wall? Ophthal Plast Reconstr Surg 19:112-118, 2003 4. Goldberg RA, Perry JD, Hortaleza V, et al: Strabismus after balanced medial plus lateral wall only orbital decompression for dysthyroid orbitopathy. Ophthalm Plast Reconstr Surg 16:271-277, 2000 5. Graham SM, Brown CL, Carter KD, et al: Medial and lateral orbital wall surgery for balanced decompression in thyroid eye disease. Laryngoscope 113:1206-1209, 2003 6. Sellari-Franceschini S, Berrettini S, Santoro A, et al: Orbital decompression in graves’ ophthalmopathy by medial and lateral wall removal. Otolaryngol Head Neck Surg 133:185-189, 2005 7. Rootman J, Stewart B, Goldberg RA: Orbital Surgery: A Conceptual Approach. Philadelphia, PA, Lippincott-Raven Publisher, 1995, pp 353-384
ORIGINAL CONTRIBUTION
Balanced orbital decompression in Graves’ orbitopathy Stefano Sellari-Franceschini, MD From The Unit of Otorhinolaryngology, Department of Neuroscience, University of Pisa, Pisa, Italy. KEYWORDS Graves’ orbitopathy; Orbital decompression; Balanced decompression; Diplopia
Graves’ ophthalmopathy is an inflammatory disease of the orbital tissues that especially affects extraocular muscles and fat. Orbital decompression is performed to reverse compressive neuropathy and reduce proptosis. The most widely used technique is the inferomedial orbital decompression, which may provide an insufficient decompression in patients with serious proptosis. A balanced decompression of the medial and lateral orbital walls provides ⬎5 mm of proptosis reduction with a low occurrence of postoperative diplopia. © 2012 Elsevier Inc. All rights reserved.
Graves’ orbitopathy is an autoimmune inflammatory disorder that involves extraocular muscles, intraconal fat, and eyelids, and it is the most common cause of exophthalmos in adulthood. Moreover, the clinical features of the disease may be different depending on the presence and prevalence of edema or fibrosis, and they include eyelid retraction or edema, proptosis, chemosis, diplopia, exposure keratopathy, and optic neuropathy. The reasons for surgery are therefore variable and can be purely cosmetic, due to serious or at least substantial proptosis, with or without diplopia, or due to optic neuropathy. Over the years, different surgical techniques have been proposed. This is because of the multifaceted nature of the disease, the different objectives for decompression, and the range of the surgeon’s skills. During the past few years, in particular, the number of rehabilitative orbital decompression operations has increased1 because the target of surgery is no longer limited to recovering vision and/or reducing proptosis but also reducing the incidence of postoperative diplopia. As far as surgical approach is concerned, there is a general consensus on the fact that the reduction of proptosis is directly correlated to the number of orbital walls removed and that diplopia is the most frequently reported side effect of orbital decompression using bone removal technique.1 Address reprint requests and correspondence: Stefano Sellari-Franceschini, MD, Unit of Otorhinolaryngology, Department of Neuroscience, University of Pisa, Via Paradisa, 2, 56124 Pisa, Italy. E-mail address: [email protected]. 1043-1810/$ -see front matter © 2012 Elsevier Inc. All rights reserved. http://dx.doi.org/10.1016/j.otot.2012.04.002
Indeed, the removal of an orbital wall not only causes a rearward movement of the eyeball but also a centrifugal displacement of rectus muscle close to the osteotomy that causes an increased duction in the direction of action of this muscle or decreased duction in the direction of its antagonist.2 Therefore, the removal of the orbital wall close to a restricted rectus muscle can be the main cause of an eye imbalance and consequently of a postoperative new onset or worsening of diplopia. Although all the extrinsic muscles can be involved in the disease, the inferior and medial rectus muscles are involved most frequently and most seriously. Vertical diplopia is even more difficult to correct because vertical fusional reserves are lower than horizontal fusional reserves, so even the smallest vertical deviation angles can cause debilitating diplopia.3 Therefore, a balanced approach to the medial and lateral wall measured in relation to the function of the medial and lateral rectus muscles is the one that in most cases allows to obtain a satisfactory reduction of proptosis with a minor risk of eye imbalance.3-6
Surgical technique This procedure is performed in patients under general anesthesia. The patient is positioned supine on the operating table. The first step in surgery is closing the eye to prevent corneal damage. We normally use an antibiotic ointment and then join
220
Figure 1
Operative Techniques in Otolaryngology, Vol 23, No 3, September 2012
Protection of the eye. Nylon stitches are used (A) to close the eyelids (B). (Color version of figure is available online.)
the eyelids with two 5/0 nylon stitches (Figure 1). In patients with serious proptosis is worthwhile not to close the eye to avoid congestion during decompression maneuvers.
Approach to the medial wall The operation starts with an endoscopic ethmoidectomy. The middle turbinate is normally removed to achieve a wider access to the lamina papiracea. Systematic opening of the sphenoidal sinus is useful as a landmark for the ethmoidal roof. Once the lamina papiracea has been skeletonized, a wide middle antrostomy is performed to expose the angle between medial and inferior orbital walls. With a Freer elevator or with a curette the lamina papiracea is fractured, and the posterior part is removed first being careful not to open the periorbita (Figure 2). In few cases, the lamina papiracea is thick, and it is useful to drill it with a diamond burr to thin the bone and make its fracture easier. In other cases, the lamina papiracea is thin and has been pushed sideways by the hypertrophic medial rectus muscle (Figure 3). In these cases, great care should be taken to not accidently open the periorbita while fracturing the papiracea. The fracture point of the lamina papiracea should be planned before the operation. The papiracea is removed by fracturing it from lateral to medial both superiorly and inferiorly, using blunt instruments, such as a Freer elevator or a curette. Based on necessity and considering the efficiency of the medial rectus muscle, the papiracea can be removed more widely in a rearward direction with backbiting forceps, but this maneuver entails more risk of accidentally breaking the periorbita. In fact, during this “bone approach,” it is necessary to be extremely careful to not open the periorbita. The penetration of the fat tissue and of the belly of the medial rectus muscle in the operative field can hinder the complete posterior removal of the lamina papiracea. It is of utmost importance to not remove the anterior because of the risk of closing the nasofrontal recess (Figure 4). The posterior third of the floor can be removed with the aid of a diamond burr (Figure 5). If the bone is thin or after
having drilled it, it can be down-fractured using the elevator or a courette introduced between the periorbita and the orbital floor. At this point, the nasal cavities are temporarily softly packed while performing the lateral orbitotomy; this because it is preferable to open the periorbita after the completion of the bone demolition (lateral and medial).
Approach to the lateral wall The most direct and cosmetically appealing approach is the upper eyelid approach, also called superior blepharoplasty. After having infiltrated the upper eyelid with a solution with vasoconstrictor, the skin is incised along the main skin crease above the upper margin of the tarsal plate (Figure 6).
Figure 2 Removal of the lamina papiracea (asterisk) with a blunt elevator. ER, ethmoidal roof; P, periorbita; SS, sphenoid sinus.
Sellari-Franceschini
Figure 3
Balanced Orbital Decompression
221
Preoperative CT scan showing enlarged medial rectus muscles that imprint the lamina papiracea.
Ideally, the incision includes the skin and the orbicularis muscle, which are tightly connected (Figure 7A). Thus, it is important not to cut too deeply to avoid lesion to the levator oculi palpebrae muscle. Therefore, it is often worthwhile to perform the incision only in the skin (Figure 7B) followed by dissection through the muscle, lifting the skin. Scissors are first used to spread underneath the orbicularis muscle (Figure 7C), and then to incise it (Figure 7D). Lifting the musculocutaneous flap, the elevation continues laterally until the frontal-zygomatic arch. Careful incision with a blade of the periosteum and lifting it beginning from the orbital frame are at this point of fundamental importance (Figure 8). Retracting the eyeball medially using a malleable elevator, the blunt dissection of the periorbita continues on the external half of the orbital roof, on all the lateral wall, and on the floor.
Figure 4 Removal of the lamina papiracea is limited to its posterior 2⁄3. Anteriorly, it is left intact to prevent the obliteration of the nasofrontal recess. P, Periorbita; ER, ethmoidal roof; pwMS, posterior wall of the maxillary sinus; ON, optic nerve; AEA, anterior etmoidal artery. (Color version of figure is available online.)
It is advisable to perform the elevation of all the periorbita in a 180 degree arc immediately (Figure 9), cauterizing the small vessels coming from the infraorbital canal, the meninx, and the bone (Figure 10). Inserting a silicone sheet (Silatos Silicone Sheeting, Atos Medical, Sweden) (Figure 11A-11C) to protect the periorbita and to prevent the penetration of orbital fat into the operating field makes surgery easier. This allows us to use a smaller malleable retractor for maximum retraction, increasing the surgical field (Figure 11D). At this point, the removal of the bone in the superolateral area is commenced with cutting, and diamond burrs until the dura of the anterior cranial fossa is seen (Figure 12). This is the landmark used to follow medially and posteriorly toward the orbital apex (Figure 13). Then, we move carefully downward until the meninx of the middle cranial fossa is seen. Then, the position of the surgeon changes to allow drilling downward (Figure 14), thinning the zygomatic arch and
Figure 5 Removal of the posterior third part of the orbital floor (medial to the infraorbital nerve) with the aid of a diamond burr. SS, sphenoid sinus; MS, maxillary sinus; ER, etmoidal roof; LP, lamina papiracea.
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Figure 8 A periosteal incision is performed on the superolateral orbital rim to begin the subperiosteal dissection.
Figure 6
Skin incision on the superior eyelid.
the bone that cover the temporalis muscle. It is a good idea not to uncover this muscle too much, as it could be traumatized by the surgical movements and bleed. At this point of the operation, it can be useful to go on to an approach to the lateral tract of the orbital floor, and the orbital floor lateral to the infraorbital nerve is drilled inferiorly. The mucous of the maxillary sinus can be simply uncovered or the sinus itself can be completely opened. At this point, the drilling continues posteriorly and inferiorly removing the residual bone lateral to the inferior orbital fissure. Before proceeding to the following stage, it is important to clean the cavity and check any possible bleeding point to
Figure 7 Incision should be made in a supratarsal skin fold (A, B). To prevent damages to the levator palpebrae muscle (pink), it is necessary to carefully dissect and cut the orbicularis oculi muscle (green) (C, D). (Color version of figure is available online.)
Sellari-Franceschini
Balanced Orbital Decompression
Figure 9 The periorbita should be elevated in a 180° arc immediately. (Color version of figure is available online.)
cauterize it, if necessary. Bleeding from the bone can be sealed with a diamond burr.
Opening of the periorbita Once the “bone stage” has been completed, which can be symmetric or asymmetric, depending on the seriousness and degree of the condition, the incision, or rather the removal of the periorbita, is begun. This is the most delicate surgical stage as regards the risk of eyeball deviation. The incisions always begin in the posterior tract of the optical cone because the fat tissue and/or the rectus muscle emerging from an accidental medial anterior opening can cover and interfere with the procedure in the deeper part. In cases of balanced decompression, the opening of the periorbita begins at the level of the lateral wall. With the help of a malleable elevator, sharp scissors are used to penetrate the periorbita at a distance of about 1 cm from the eyeball equator (Figure 15): the scissors are then opened to lacerate the periorbita. At this point, the periorbita behind this incision line is cut in an anterior–posterior direction, until it is completely removed (Figure 16). Then, the same procedure is continued to remove the periorbita, leaving the outermost 5-10 mm to leave support for the muscle pulleys system. It should be borne in mind that, superiorly, V1 lies on the levator palpebrae superioris muscle, thus careful attention must be paid so as not to damage it when working at this level. Following this, the periorbita of the medial wall is opened. The incision begins from the apex in a posterior to anterior direction using a sickle knife (Figure 17). Sparing the anterior third, or half, of the wall to reduce the risk of a postoperative esotropia. At this point, still with the scissors externally and sickle knife through the nasal approach, the fat tissue can be manipulated, breaking the septa between the various sections. Then, by careful cauterization, part of the fat tissue can be removed (Figure 18). It is advisable to remove only the fat tissue of the inferior lateral section (inferiorly to the lateral rectus muscle), as this is safer as far as the possibility
223 of causing postoperative diplopia is concerned. If necessary, to increase the decompression, the fat tissue found above the medial rectus muscle can be moved medially. To this end, it can be helpful to cut it with a sickle knife, helping with light pressure on the eyeball. It is not advisable to perform the same maneuver medially, on the fat tissue inferior to the medial rectus muscle because, despite having a good decompressive effect, it has the disadvantage of a good chance of postoperative esotropia, often not rectifiable intraoperatively. All these actions on the fat tissue should be performed alternatively on each of the 2 eyes, to balance the decompression. Experience has shown that the most involved eye is also the most difficult to decompress, and thus it could be a good practice to begin any maneuver with the worst eye, than balancing the reduction of the proptosis by working on the other. Once the maximum obtainable decompression has been reached, above all on the basis of the patient’s needs, the operation is practically finished. As regards the nasal access, this can be finished without placing swabs or with a small nasal sponge dressing. It is better to insert this into a surgical glove finger to avoid adhesion to the orbital content. Two silicon tubes can be placed in addition to the swabs to improve the next 48 hours of the patient with a minimum of respiratory opening. As regards the translid approach, an intradermal suture with nylon 4/0 will suffice. It can be useful, and also prudent from a legal point of view, to place drainage in the external section of the orbit for 24 hours.
Results A total of 327 patients (638 orbits) were decompressed using this technique between 1998 and 2009, in the ENT Unit of the University of Pisa.
Figure 10 A careful cauterization of the small vessels coming out from the bone to the periorbita is needed during elevation of the periorbita from the bone. (Color version of figure is available online.)
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Figure 11 Positioning a plastic (Silastic) sheet helps in preventing damage to the periorbita. A, Elevation of the periorbita; B, shaping of a Silastic sheet; C, insertion of the Silastic sheet; D, Silastic sheet in position: this allows us to use a smaller malleable retractor for maximum retraction. (Color version of figure is available online.)
Although the medial and lateral walls were approached in all patients, the amount of bone demolition was different in some patients based on the workings of the extrinsic muscles and the amount of proptosis. As regards muscle function, if the medial rectus muscle or, more rarely, the lateral rectus became restricted, a reduction of the opening of the medial or lateral walls was attempted to avoid muscle displacement, with a consequent increase in the deficit of eye motility. As far as the reduction in proptosis was concerned, the amount of osteotomy and opening of the periorbita were varied during the operation so as not to cause enophthalmos, and in bilateral asymmetric cases, to balance the decompression in the 2 eyes.
With this technique and following these surgical principles, the average proptosis reduction was 5.81 ⫾ 2.45 mm (range 0-14 mm) with a 13.2% of postoperative new primary gaze diplopia (patients with a preoperative motility disturbance were excluded during this analysis of postoperative diplopia). We observed 2 intraoperative and 4 major postoperative complications. The first were connected to the endonasal approach: 2 rhino-liquorrea, 1 closed intraoperatively, and 1 closed after 2 days, when it became evident. As regards postoperative complication, we had to operate on 2 patients on the following day for retrobulbar hemorrhage, due to the removal of the drainage accidentally per-
Figure 12 The removal of the lateral orbital wall is made by drilling the bone. (Color version of figure is available online.)
Figure 13 Extent of the lateral bone removal at the end of surgery. (Color version of figure is available online.)
Sellari-Franceschini
Balanced Orbital Decompression
Figure 14
Position of the surgeon while drilling the lateral wall (left) or the orbital floor (right).
formed by the patient. Two other patients demonstrated a visual loss due to compression of the optic nerve, from ethmoidal bone fragments, with a similar need for revision surgery, resulting in a recovery of vision in both cases.
Discussion Graves’ orbitopathy is an inflammatory disease, which mainly affects the fat tissue and the extraocular muscles. After the inflammatory process, the muscles are enlarged, and a result of fibrosis and fact degeneration,1 this muscular dysfunction can cause eye imbalance or lead to postoperative imbalance. Diplopia is, in fact, the most frequent post-
Figure 15
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Opening of the periorbita with sharp scissors.
operative complication. Therefore, it is important to adapt the technique to the needs of the patient, providing a balanced technique. The technique we report is free from disfigurement of the orbital profile. Removing the great sphenoidal wing together with, if necessary, the external part of the roof and the external part of the floor allow the correction obtained with the ethmoidectomy to be better balanced. Lateral bone demolition can be performed by a translid incision, which provides a direct approach to the lateral orbital wall. In addition, the opening of the periorbita and remodeling of the fat medially and laterally permit a progressive reduction and balancing of the proptosis.
Figure 16 periorbita.
Drawing illustrating the first lateral incisions of the
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With this in mind, it can also be useful to remove the fat tissue, and based on both personal experience and the literature7 in the field, it is advisable to remove only the fat tissue of the inferolateral section, as it is safer as far as postoperative diplopia is concerned.
Conclusions Graves’ orbitopathy is a disease that involves the extrinsic muscles of the eye, the retro-orbital fat tissue, and eyelids in an extremely variable manner. All of these structures can be affected in different ways in either one or both eyes. Therefore, there is a great deal of variation in clinical manifestation. Within the particulars, a balanced decompression technique is described that allows a good reduction in proptosis and a reduced possibility of postoperative diplopia through removal of the medial and lateral bone walls.
Figure 18 After the periorbita has been opened, the retrobulbar fat is manipulated and partially removed.
In addition, the opening of the periorbita and removal of fat tissue are dealt with in detail. Furthermore, with this technique, the surgeon is also in a position to tackle both the most serious cases with optic neuropathy and particular cases in which it is important to avoid worsening existing serious eye imbalance, varying the way of approach toward the walls. Drawing on a personal experience of 327 patients operated on using this technique, an analysis of the results is also put forward, and intra- and postoperative complications are also covered.
References
Figure 17 The periorbita is opened transnasally with the aid of a sickle knife.
1. Siracuse-Lee DE, Kazim M: Orbital decompression: current concepts. Curr Opin Ophthalmol 13:310-316, 2002 2. Abràmoff MD, Kalman R, De Graaf MEL, et al: Rectus extraocular muscle paths and decompression surgery for Graves orbitopathy: mechanism of motility disturbances. IOVS 43:300-307, 2002 3. Unal M, Leri F, Konuk O, et al: Balanced orbital decompression combined with fat removal in graves ophthalmology: do we really need to remove the third wall? Ophthal Plast Reconstr Surg 19:112-118, 2003 4. Goldberg RA, Perry JD, Hortaleza V, et al: Strabismus after balanced medial plus lateral wall only orbital decompression for dysthyroid orbitopathy. Ophthalm Plast Reconstr Surg 16:271-277, 2000 5. Graham SM, Brown CL, Carter KD, et al: Medial and lateral orbital wall surgery for balanced decompression in thyroid eye disease. Laryngoscope 113:1206-1209, 2003 6. Sellari-Franceschini S, Berrettini S, Santoro A, et al: Orbital decompression in graves’ ophthalmopathy by medial and lateral wall removal. Otolaryngol Head Neck Surg 133:185-189, 2005 7. Rootman J, Stewart B, Goldberg RA: Orbital Surgery: A Conceptual Approach. Philadelphia, PA, Lippincott-Raven Publisher, 1995, pp 353-384