Endoscopic drainage of subperiosteal orbital abscesses

ENDOSCOPIC DRAINAGE OF SUBPERIOSTEAL ORBITAL ABSCESSES SCOTT

C.

MANNING,

MD

Medial subperiosteal orbital abscess is the most common suppurative complication of sinusitis. Small abscesses, especially in young children, may respond to therapy with intravenous antibiotics. Surgical drainage is indicated for large abscesses or for failure to respond to medical management. Traditionally, external ethmoidectomy approaches have been used to gain access to the medial orbital subperiosteal space. In our institution, an endoscopic ethmoidectomy approach has been used over the last decade, with advantages of avoidance of a facial scar and more rapid resolution of periorbital inflammation.

The majority of cases of periorbital inflammation occur in patients under age 20 years. The term orbital cellulitis encompasses all forms of periorbital inflammation, but the treatment plan depends primarily on the exact anatomic location of the infection. Preseptal cellullitis, by definition, does not involve the orbit or globe, and this condition is most common in children under age 3 years. Hematogenous seeding from Hemophilus influenza B (HIB) infection was the most common etiology before the introduction of the HIB vaccine in 1991. Today, positive blood cultures in patients with preseptal cellulitis are most likely to show Streptococcus pneumoniae. Most patients are easily treated with oral or intravenous antibiotics, depending on their severity at presentation. Postseptal cellulitis is defined clinically by orbital signs such as proptosis, chemosis, and ophthalmoplegia. The most common form of postseptal inflammation is medial subperiosteal orbital abscess (SPOA), which is caused by direct extension of infection from adjacent ethmoiditis. The most common physical signs associated with medial SPOA are lateral displacement of the globe with limited adduction. Infection inside the periorbita (intraconal) is relatively unusual, and potential predisposing conditions include penetrating injury, underlying immunodeficiency, or long-standing, inadequately treated SPOA. Cavernous sinus thrombosis is extremely rare and is caused by further extension of intraconal infection through the orbital apex along vascular channels.

CLINICAL AND IMAGING ASSESSMENT Patients with postseptal cellulitis should ideally be evaluated both by otolaryngology and ophthalmology on presentation. The otolaryngology examination should document signs of associated sinusitis, which is the most common predisposing factor, especially in young children. The ophthalmology examination should ideally include visual acuity, assessment of gaze restriction, measurement From the University of Washington and Children's Hospital and Regional Medical Center Seattle, Seattle, WA. Address reprint requests to Scott C. Manning MD, 4800 Sandpoint Way NE, Seattle, WA 98105-0371. Copyright 2002, Elsevier Science (USA). All rights reserved. 1043-1810/02/1301-0017535.00/0

doi:10.1053/otot.2002.31394

of proptosis, and a fundus examination. Presenting signs associated with a need for early surgical management include proptosis greater than 2 mm, 1 visual acuity less than 20/60, older age group, and immunodeficiency or diabetes. In addition to the above mentioned signs, neurologic symptoms should prompt immediate imaging. Young children with significant lid edema present difficult challenges for physical and ophthalmologic assessment, and overall toxic appearance should be another indication for rapid imaging. Axial computed tomography (CT) is usually the first imaging choice, especially for younger children who are more difficult to position for coronal imaging (Fig 1). Axial CT is best for showing medial SPOA, but coronal imaging is indicated when superior or inferior orbital disease is suspected (Fig 2). Axial CT is also best for showing associated intracranial epidural frontal abscess but sinus algorithms by themselves are inadequate for assessing suspected intracranial disease. CT is relatively nonspecific in showing the point where inflammation and phlegmon becomes liquified abscess, and studies have shown a significant false negative rate. Thus, absence of a definite abscess on CT should not preclude surgical drainage in the face of progression of orbital signs and symptoms. Some of the variation in the literature in response rates to medical therapy is because of institutional differences in the threshold for defining abscess versus phlegmon by CT. 2 The most common CT appearance of medial SPOA is that of a mass effect between lamina papyracea and the medial rectus muscle with an enhancing periphery and a low-density center. Gas is relatively unusual finding. Magnetic resonance imaging is the most sensitive way to rule out associated intracranial disease and may also be more sensitive than CT for evaluating intraconal orbital inflammation.

MEDICAL THERAPY Postseptal orbital cellulits patients with favorable presentations (visual acuity normal or near normal, proptosis less than 2 mm, good pupillary reflex, no history of immunodeficiency) are treated initially with intravenous antibiotics. Patients under age 9 years are more likely to have a single pathogen, usually Haemophilus influenza, Moraxella catarrhalis, Streptococcus pneumonia, or Staphylococcus aureus, and are likely to be cured with medical therapy

OPERATIVE TECHNIQUES IN OTOLARYNGOLOGY--HEAD AND NECK SURGERY, VOL 13, NO 1 (MAR), 2002: PP 73-76

73

in the older age group (older than age 9), or patients with dental origin of infection, have a relatively low likelihood of timely resolution with intravenous antibiotics alone. Most authors cite progression of orbital signs a n d / o r failure of improvement after 36 to 48 hours of intravenous antibiotics as the principle indication for surgical intervention when imaging is consistent with abscess formation.7'8 Blindness from orbital cellulitis still occurs, and it is associated with diabetes or other immunodeficiency state and with failure to intervene surgically in the face of progressing orbital signs with antibiotic therapy. 9 Most SPOAs are medial, and the traditional surgical approach has been via an external ethmoidectomy incision placed midway between the midline nasal dorsum and the medial canthus. The first published description of an endoscopic approach was a series of 6 pediatric patients from my service in 1993.1~ The advantages of avoiding a facial scar, eliminating surgical edema, and shortening the hospital stay has led to a shift to endoscopic techniques for accessable medial SPOAs in many pediatric teritiary care centers.

FIGURE 1. Axial CT of 9-year-old girl with a retrobulbar SPOA and adjacent ethmoiditis. Gas within the abscess indicates probability of mixed infection with anerobes.

alone. 3 Many authors recommend ceftriaxone sodium because of good coverage of common respiratory pathogens and good penetration of the blood-brain barrier. Clindamycin is another common initial choice when central nervous system involvement is not suspected, because of its excellent coverage of both Staphylococcus aureus and oral flora including anaerobes. 4 Children older than age 9 are more likely to have a mixed polymicrobial infection and initial therapy should include coverage for anaerobes. Mixed infection is very likely in patients older than age 15 with imaging evidence of abscess formation. The incidence of associated intracranial infection is also higher in teenagers and young adults. Ceftriaxone plus clindamycin is a common initial therapeutic choice for older patients. When dental origen is suspected, some authors recommend penicillun plus metronidazole. INDICATIONS

Patients are positioned on the operating table as for standard endoscopic ethmoidectomy in a slightly head-up position. Oxymetazoline hydrochloride 0.05%-impregnated cottonoid strips are placed in the nasal cavities for 10 minutes for vasoconstriction before injection. Cocaine is no longer used for our pediatric patients because of concerns about cardiac excitability when used in conjunction with halothane. The nasal cavities are then inspected with a 0 ~ 4-mm endoscope, and the head of the middle turbinate and the area of the uncinate process on the involved side are injected with 1% lidocaine hydrochloride solution. The middle turbinate is gentle reflected medially and the bulla ethmoidalis is visualized. If the bulla cannot be easily identified, as is often the case in young children, then a partial uncinectomy is performed with either a

FOR SURGERY

Younger patients with CT evidence of medial subperiostial phlegrnon or small abscess have a good chance of resolving their infection with medical therapy alone.5 Sajjadian et al have described a series of 14 consecutive pediatric patients, mean age 5.5 years, with medial SPOA, which is defined as some CT evidence of mass effect adjacent to the ethmoid with medial displacement of the medial rectus. 3 Of the 14 patients, 12 were successfully treated with medical therapy alone, whereas 2 required surgical drainage. Harris has described successful treatment of CT defined medial SPOAs with 2- to 3-week courses of intravenous antibiotics with the proposed advantage of avoiding a facial scar and the potential for seeding bacteria to distant sites. 6 The former concern can be addressed by using an endoscopic technique, but the latter is hard to assess because patients have presented with intracranial abscess weeks after medical or surgical therapy. On the other hand, patients who present with larger abscesses (often clinically associated with greater than 2 mm of proptosis and significant gaze restriction) and are

"74

OPERATIVE TECHNIQUE

FIGURE 2. Coronal CT of a 3-year-old girl with a medial-inferior abscess with adjacent ethmoid and maxillary sinusitis. This patient had a presumed dental origin from carious primary teeth. ENDOSCOPIC DRAINAGE OF SPOA

Freer elevator or a microdebrider after carefully medializing the uncinate with a curved ball seeker in the hiatus semilunaris. Some patients with SPOA have evidence of significant allergic rhinitis (possibly a predisposing factor) with polypoid mucosa of the middle turbinate head blocking access to the middle meatus. In that case, the microdebrider can be used to carefully remove r e d u n d a n t mucosa from the lateral aspect of the head of the middle turbinate. The bulla (the second tamella after the uncinate) is then carefully opened with either a straight forceps or a small straight suction. Hypertrophic mucosa is removed with the 4-mm straight microdebrider until the lamina papyracea is well-visualized laterally. Most SPOAs are located in the middle to anterior medial orbit opposite the bulla. A dehiscence can often be seen in the lamina once the bulla is completely opened, and gentle external pressure on the globe may result in the appearance of purulent exudate through the dehiscence (Fig 3). The dehiscence can then be enlarged by removing a portion of the lamina with straight forceps and the curved ball seeker (Fig 4). When the medial subperiosteal space is completely drained, gentle external pressure on the globe will result in the appearance of smooth white periorbita seen from the ethmoid through the dehiscence in the lamina. For patients with long-standing inflammation, significant granulation tissue may be encountered just lateral to the lamina, and periorbita may not be well visualized. Gentle probing of the granulation with a blunt instrument may yield pockets of purulence that can be easily communicated to the ethmoid cavity (Fig 5). The microdebrider should not be used once a bony dehiscence has been created, especially on granulation tissue, because it could potentially pull in and injure orbital contents such as the medial rectus muscle. By definition, patients with SPOAs have acute infection, and the ethmoid contents are therefore often inflamed and vascular. Slow and deliberate technique with frequent pauses to pack with oxymetazoine-dampened cottonoids helps to maintain an adequate optical environment. The smaller, 2.7-mm endoscopes may be necessary within the ethmoid sinus of younger children. The microdebrider,

Periorhita

R( U[

Lamina papyracea FIGURE 4. More proximal view. The defect can be enlarged by carefully removing more lamina.

with its relative atraumatic action versus pulling forceps, can be a great advantage in the face of acute infection. The extent of surgery and of removal of orbital bone depends on the location of the abscess. SPOAs, which extend more posteriorly, may require a total ethmoidectomy with removal of the ground lamella into posterior ethmoid cells. More anterior superior abscesses may require opening of the frontal recess cells to gain sufficient access for removal of the relevant lamina. Surgeons with experience in orbital decompression for thyroid eye disease may feel comfortable in approaching the unusual problem of abscess extension into the medial inferior subperiosteal space. In that situation, the medial orbital floor is approached through a wide middle meatus antrostomy. A fracture is made in the orbital floor with a small curved

Periorbita

,t

ethJ Middle turbinate FIGURE 3. Drawing of a small defect in the lamina after opening the bulla. SCOTT C. MANNING

FIGURE 5. Endoscopic view of a left ethmoid cavity. A blunt suction tip is seen inferiorly gently teasing away a piece of more posterior lamina. This was a mature abscess, with pockets of granulation and purulence seen instead of smooth periorbita. 75

frontal epidural abscess treated in conjunction with neur o s u r g e r y service. N o patient in the series experienced p e r m a n e n t loss of vision or gaze restriction.

DISCUSSION Lami papyra

FIGURE 6, Schematic view of completed left ethmoidectomy with removal of enough lamina to create an appropriate communication to the subperiorbital space. chisel, a n d b o n e is r e m o v e d up" to the infraorbital nerve. The medial buttress b e t w e e n the lamina a n d the medial orbital floor is p r e s e r v e d to p r e v e n t m e d i a l entropion. By definition, SPOAs are outside the periorbita; therefore, the periorbita is not incised d u r i n g surgery. W h e n periorbita is seen flush w i t h the created lamina defect c o r r e s p o n d i n g to the anatomic location of the abscess b y CT, then the operation is c o m p l e t e d (Fig 6). Bleeding is controlled w i t h bipolar cautery a n d w i t h thin layers of absorbable hemostatic gauze. N o n o n a b s o r b a b l e packing material or stents are used.

Endoscopic drainage of SPOAs offers the potential a d v a n tages of a v o i d a n c e of a facial scar, elimination of surgical e d e m a , a n d possibly shorter hospitalization. The technique a p p r o a c h e s the disease process f r o m the p a t h of its origin within the e t h m o i d sinus w i t h the goal of establishing natural d r a i n a g e b a c k t h r o u g h the nose. The endoscopic technique can be u s e d for m e d i a l disease, including s o m e superior a n d inferior extension, dep e n d i n g on the experience of the surgeon. It cannot be u s e d for disease in the lateral half of the orbit. In m y experience, endoscopic a p p r o a c h e s are reserved for infection in the subperiosteal space. Intraconal infection, fortunately rare, is a p p r o a c h e d externally with the o p h t h a l m o l o g y service. M a n n et al n h a v e r e p o r t e d on several cases of medial intraconal abscess a p p r o a c h e d endoscopically w i t h incision of the periorbita, a n d as surgeons gain experience, this m a y r e p r e s e n t a natural extension of the technique. Froehlich et al h a v e described a series of v e r y focused o p e n i n g of the bulla only to a p p r o a c h the m o s t c o m m o n location of m e d i a l SPOA. 12 In m y experience, it is often necessary to at least p e r f o r m a complete o p e n i n g of the m i d d l e e t h m o i d cells to r e m o v e e n o u g h bleeding m u c o s a to create an a d e q u a t e optical e n v i r o n m e n t for r e m o v a l of the a p p r o p r i a t e lamina. Endoscopic sinus s u r g e r y is m o r e difficult in y o u n g children because of smaller a n a t o m y , a n d the endoscopic a p p r o a c h to m e d i a l SPOA should only be considered b y s u r g e o n s w h o are comfortable w i t h m o r e routine pediatric endoscopic sinus s u r g e r y cases.

REFERENCES RESULTS M y personal series consists of 27 patients with SPOA treated over the last 12 years. Two patients h a d lateral superior SPOA p r e s u m a b l y caused b y extension f r o m infection in supraorbital ethmoid cells, and these abscesses were approached via an u p p e r eyelid incision. One patient h a d a large medial SPOA extending into the orbital floor; this was approached successfully b y a combination ethmoid and middle meatus antrostomy with removal of both lamina and medial orbital floor. The remaining patients were approached as described earlier for medial SPOA. The m e a n discharge time w a s 3.5 d a y s after surgery, a n d the m e a n total hospitalization w a s 6.5 days. Most of the surgical patients w e r e discharged on oral antibiotics, in contrast to patients in r e p o r t e d series of medical treatm e n t w h o required up to 2 to 3 w e e k s of i n t r a v e n o u s antibiotics. 6 One 16-year-old patient w i t h a m i x e d aerobicanaerobic infection failed to resolve his periorbital cellutis after endoscopic d r a i n a g e of his medial SPOA, a n d repeat CT on p o s t o p e r a t i v e d a y 2 s h o w e d a lateral intraconal orbital abscess. The patient r e c o v e r e d u n e v e n t f u l l y after a lateral a p p r o a c h drainage p r o c e d u r e b y o p h t h a l m o l o g y service, b u t he required 3 w e e k s of i n t r a v e n o u s antibiotics. Three patients required separate lid incision a n d d r a i n a g e p r o c e d u r e s for soft tissue abscesses separate f r o m their m e d i a l SPOA. One of these lid abscesses w a s a p p a r e n t on intitial CT, a n d the other t w o w e r e d i s c o v e r e d on p o s t o p erative d a y 2 after repeat imaging, w h e n lid e d e m a failed to resolve despite resolution of orbital signs. O n e patient in the series w i t h neurologic signs on p r e s e n t a t i o n h a d a

76

1. Rahbar R, Robson CD, Petersen RA, et al: Management of orbital subperiosteal abscess in children. Arch Otolaryngol Head Neck Surg 127:281-286, 2001 2. Sajjadian A, Chundru U, Isaacson G: Prospective application of a protocol for selective nonsurgical management of suspected orbital subperiosteal abscessed in children. Ann Otol Rhinol Laryngol 108: 459-462, 1999 3. Garcia GH, Harris GJ: Criteria for nonsurgical management of subperiosteal abscess of the orbit: Analysis of outcomes. Ophthalmology 107:1454-1456, 2000 4. Manning SC: Orbital cellulitis and abscess, in Gates GA (ed): Current Therapy in Otolaryngology--Head and Neck Surgery, ed 6. St. Louis, MO, Mosby-Year Book Inc, 1998, pp 359-362 5. Souliere CR, Antoine GA, Martin MP, et al: Selective nonsurgical management of subperiosteal abscess of the orbit: Computerized tomography and clinical course as indication for surgical drainage. Int J Pediatr Oto Rhinolaryngol 19:109-119, 1990 6. Harris GJ: Subperiosteal abscess of the orbit. Ophthalmology 101:585595, 1994 7. Pereira KD, Mitchell RB, Younis RT, et al: Management of medial subperiosteal abscess of the orbit in children--A 5 year experience. Int J Pediatr Oto Rhino Laryngol 38:247-254, 1997 8. Deutsch E, Eilon A, Hevron I, et al: Functional endoscopic sinus surgery of orbital subperiosteal abscess in children, lnt J Pediatr Oto Rhino Laryngol 34:181-190, 1996 9. Patt BS, Manning SC: Blindness resulting from orbital complication of sinusitis. Otolaryngol Head Neck Surg 104:789-798, 1991 10. Manning SC: Endoscopic management of medial subperiosteal orbital abscess. Arch Otolaryngol Head Neck Surg 119:789:791, 1993 11. Mann W, Amedee RG, Maurer J: Orbital complications of pediatric sinusitis: Treatment of periorbital abscess. Am J Rhinol 11:149-153, 1997 12. Froehlich P, Pransky SM, Fontaine P, et al: Minimal endoscopic approach to subperiosteal abscess. Arch Otolaryngol Head Neck Surg 123:280-282, 1997 ENDOSCOPIC DRAINAGEOF SPOA