“DOCENDO DECIMUS”

VOL 3 No 8 AUGUST 2016

DCMC Emergency Department Radiology Case of the Month

These cases have been removed of identifying information. These cases are intended for peer review and educational purposes only.

Welcome to the DCMC Emergency Department Radiology Case of the Month!

In conjunction with our pediatric radiology specialists from ARA, we hope you enjoy these monthly radiological highlights from the case files of the Emergency Department at DCMC. These cases are meant to highlight important chief complaints, cases, and radiology findings that we all encounter every day. Conference Schedule: August 2016 3rd 9:15 Radiology Rounds: c-spine…Drs McClug & Vezzetti If you enjoy these reviews, we invite you to 10:15 Biostats 2………………………..……….Dr Wilkinson check out Pediatric Emergency Medicine 5th PEM Fellow Interview Day!

Fellowship Radiology rounds, which are offered 9th Finding a job/Contracts……………………Drs Allen & Yee quarterly and are held with the outstanding 10th 8:00 Complex Airway Management………….Dr Vezzetti support of the pediatric radiology specialists at 9:00 Simulation: Respiratory….……Simulation Faculty Austin Radiologic Association. 17th 10:15 Ultrasound in the ED……….…Drs Levine & Gorn 12:00 ED Staff Meeting

If you have and questions or feedback regarding 19th PEM Fellow Interview Day! the Case of the Month format, feel free to 23rd Research Round Table……………….….……Dr Johnson email Robert Vezzetti, MD at 24th 9:15 Global and Indigent Care……………….Dr Bonnell [email protected]. 10:15 Coagulopathies…………………..Drs Gorn & Irwin 11:15 Hemoglobinopathies….Drs Schwartz & Schwarz

This Month: Facial swelling in a child without trauma! 31st 9:15 M&M…………………….…………Drs Wyrick & Irwin 10:15 Board review: GI…………………..……Dr Gardiner You don’t want to miss this diagnosis in your patients, as 12:15 Research Update………………………Dr Wilkinson the sequelae of doing so can be disastrous. A special Page 1 thanks to Drs Guyon Hill (PEM Fellow) and Sujit Iyer (PEM Simulations are held at the CEC at UMC Breckenridge. Attending) and Brittany Christianson (ED NP) who Lectures are held at DCMC Command Rooms 3&4. provided this case. Locations subject to change. All are welcome! The Romans gave August its name in 8BC, after the first Roman Emperor Augustus who ruled from 27BC until his death in AD14. VOL 3 No 8 AUGUST 2016

Case: It’s a nice, quite, summer evening in the Pediatric Emergency Department; some fractures, bug bites, allergies, the occasional trauma, but not much else. There has been, you’ve noticed, a bit of an uptick in cellulitis and abscesses, but not nearly the amount that a typical summer brings. Oddly enough, just as you are thinking this, you pick up a chart that has a chief complaint of facial erythema and edema. Hmm… You speak to the parents and learn that your patient is an 11 year old male with 4 days of progressively worsening facial erythema and edema. The child has been in good health, with the exception of a history of asthma and sinus infections in the past. He and his parents state that the involved area is somewhat itchy but he denies insect bites/stings or any other trauma. There is no history of fever, cough, congestion, vomiting, or headache, but the child has had a “runny nose” for the past few weeks which seems to be improving with his allergy medications. He was seen yesterday at Urgent Care and was diagnosed with a facial cellulitis. He was started on Keflex four times a day. The parents report that the child’s symptoms appear worse and they are concerned that the antibiotics are not helping. He denies vision changes, eye discharge, the feeling that there is a foreign object in the eye, or painful eye movements. This is good, because when you examine the child you note some impressive erythema and edema of the left side of the face (as seen on the right; this is a depiction from the chart illustration). He is afebrile but mildly tachycardia (heart rate 110) and complains of tenderness when you palpate the erythematous area. There is warmth as well but no fluctuance or streaking. There is no photophobia or proptosis and his extra-oscular muscles are grossly intact; he does complain of some pain with upward gaze but the pain he localizes to his forehead. He is able to partially open his eye, but this is difficult secondary to the edema. His neurologic examination seems grossly normal and he is otherwise in no distress. This child clearly has cellulitis, but the soft tissue swelling he is demonstrating is significant. Could he have an abscess as well? Does he have orbital involvement? How can you tell one way or the other? Will imaging help and if so, what study should you get?

Imaging facial infections is important to rule out complications, such as a facial abscess or to evaluate for orbital involvement, such as occurs with orbital cellulitis. In cases where cellulitis is minimal, imaging is not warranted. However, if there is any question of facial abscess or orbital involvement, then imaging is indicated. Options include : 1. CT - with IV contrast material. CT is very quick and certainly can be effective in evaluating a patient for an abscess or orbital involvement. However, it is difficult to distinguish on CT scanning between preseptal edema and periorbital cellulitis. As always, radiation exposure is a concern. 2. MRI - generally MRI is not indicated and often will not significantly impact management. This modality can be useful if there is a concern for brain involvement (ie empyema). No ionizing radiation, but this imaging technique requires the patient to remain still for a useful study.

Page 2 On Aug. 21, 1911, the Mona Lisa was stolen from the Louvre Gallery and not recovered for two years. After one of his assistants working on his X-ray project showed signs of illness, Thomas Edison said, “Don’t talk to me about X-rays. I am afraid of them.” VOL 3 No 8 AUGUST 2016

Given the extent of the edema, warmth, and tenderness, the concern for an abscess is paramount. The imaging options include ultrasound, CT, and MRI. While ultrasound is quick, involves no ionizing radiation, and readily available, the extent of the child’s symptoms are concerning for an orbital process as well, so this imaging modality will not be particularly helpful. MRI would be great at detecting fine detail and if there is any optic nerve or muscle involvement. But this imaging test is time consuming and may require sedation. In this patient, CT with IV contrast is the most appropriate imaging modality. While this requires IV placement and involves, of course, ionizing radiation, it is also very quick (a few seconds with today’s scanners) and can rule out an abscess, boy involvement, and orbital involvement. CT it is…

Selected CT images are seen here above and to the right. The first finding is the presence of soft tissue edema (yellow arrow). There is also left frontal ethmoid and maxillary sinusitis (red arrow). More concerning, though, is the erosion of the frontal sinusitis to the left frontal soft tissues, causing what appears to be a subperiosteal abscess (blue arrow), which runs inferiorly resulting in a post septal superior orbital abscess (purple arrow). finally, there is a questionable frontal empyema (green arrow). Wow. Now what? further imaging? Admission? Antibiotics?

1873 - The Clay Street Hill Railroad began Page 3 operating the first cable car in San Francisco's famous cable car system. August 1610 - Henry Hudson sailed into what is now known as Hudson Bay (he thought he had made it through VOL 3 No 8 the Northwest Passage, and reached the Pacific Ocean). AUGUST 2016

The CT images are concerning for a serious infection, including an orbital abscess and possible frontal empyema. Pediatric Occuloplastics and Pediatric ENT were initially consulted. Both agreed that an MRI may be helpful in this case, especially since there is a concern for a frontal empyema. Selected images from that study are seen here. Note the left maxillary/ ethmoid sinusitis (yellow arrow). There is subperiosteal abscess (red arrow) with septal extension, but no obvious abscess. There is no epidural abscess noted. Now what? T2 image

T1 image T2 image

The MRI shows that there is indeed cellulitis and a subperiosteal abscess. Although this abscess extends to and involves the septum, there does not appear to be an orbital abscess. Additional good

news is the apparent lack of frontal epyema. The superisoteal abscess does extend to the orbit and involves the septum. This is consistent with orbital cellulitis. What happened next? Read on and find out…

What is the orbital septum? This is a thin fibrous sheet that comes from the orbital rim periosteum and meets the tendon of the Page 4 levator palpebral superioris and the tarsal plate. Penicillin discoverer Alexander Fleming (1881-1955) was born August 6th in Lochfield, Scotland. By accident, he found that mold from soil killed deadly bacteria without injuring VOL 3 No 8 human tissue. He received the Nobel Prize in 1954. AUGUST 2016

Periorbital cellulitis is often the result of contiguous spread of an infection typically involving the face or teeth. These infections are limited to the soft tissues that are anterior to the orbital septum. Orbital cellulitis is typically the result of a paranasal sinus infection. This infection extends posterior to the orbital septum. It is important to distinguish between these two clinical entities, as orbital cellulitis, being a more serious infection, is managed with hospitalization and parenteral antibiotics.

Sometimes, it can be difficult to clinically distinguish between orbital and periorbital cellulitis. Orbital cellulitis classically presents with proptosis, decreased visual acuity, fever, and an overall more toxic appearing child.

This is a very nice (and easily seen) image of a subperiosteal abscess (red arrow). Note on the coronal view (far right), there is extensive sinus disease (blue arrow) and the enhancing area actually displaces the globe! When looking at CT contrast enhanced imaging for orbital cellulitis three important questions need to be addressed: 1. Is there a subperiosteal fluid collection? 2. Is there extra cranial invlvement/extension? 3. Is severe sinusitis present?

FROM: radiopaedia.org

In this image on the bottom left, one can see increased attenuation of the fat planes of the left periorbital area, extending along the medical rectus muscle (blue arrow). This is consistent with perioribital infection. The image in the right shows pretty typical findings as well, demonstrating soft tissue edema (yellow arrow) and normal appearing retro-orbital fat (red arrows).

Page 5

FROM: radiopaedia.org FROM: radiopaedia.org August 18th - The 19th Amendment to the U.S. Constitution was ratified, granting women the right to vote. VOL 3 No 8 AUGUST 2016

Antibiotic Coverage for Orbital and Periorbital Infections Treatment for both periorbital and orbital infections involves antibiotics. For periorbital infections, outpatient management with oral antibiotics is appropriate. There are times when a child needs admission to the hospital for IV antibiotics, including failure to respond to an appropriate oral regimen , inability to take oral medications, noncompliance, or concern for complications. For orbital infections, admission for IV antibiotics as well as subspecialty consultation (Pediatric Ophthalmology, Pediatric Otolaryngology, and Pediatric Infectious Disease are the usual consultants; if there is concern for cerebral involvement, then Pediatric Neurosurgery should also be consulted). The most common organisms that cause periorbital cellulitis include Staphylococcus aureus, Staphylococcus epidermis, Streptococcus species, and anaerobes. Prior to the widespread use of the Haemophilus influenza Type B vaccines, this was a very common cause of periorbital infections, but this is much less common cause of infection now. Blood cultures are seldom positive in children with periorbital cellulitis. Orbital cellulitis is a true emergency. Most commonly this is associated with ethmoid sinusitis. While the same organisms that cause periorbital cellulitis can cause orbital cellulitis, anaerobic organisms are implicated most commonly. Polymicrobial infections are also common in older children. Ocular trauma can be a cause of orbital cellulitis when an injury perforates the orbital septum. Appropriate antibiotic therapy for periorbital cellulitis can be done on an outpatient basis or inpatient basis, depending on the history of the patient. For initial therapy in a well-appearing child with no suspicion of orbital involvement, Augmentin or Clindamycin are good first choices. If the infection is suspected to be due to an insect bite, minor skin trauma, or MRSA is suspected, then Bactrim or, more commonly, Clindamycin is suggested. IV therapy for children who are ill-appearing or failing outpatient management includes Ceftriaxone or Zisyn/Unasyn with either Clindamycin or Vancomycin (in ill-appearing children). Animal bites are treated with Augmentin. Orbital cellulitis treatment involves initial broad spectrum coverage which can then be tailored following culture results after abscess drainage. Ceftriaxone with Clindamycin or Zosyn/Unasyn with Clindamycin are good first choices. In children who look particularly ill or who may be taking oral Clindamycin for presumed periorbital cellulitis, Vancomycin can be added as well. In immunocompromised children, anti-fungal coverage should be considered.

FROM: occuplastics.com

While there is evidence that small periosteal abscesses can be managed successfully with antibiotics, surgical drainage is also commonly used and some studies suggest that combining the two treatment modalities results in more successful management. Surgical approaches include an external approach and an endoscopic approach. The difference in success of these two approaches has been found to be related to the number of extra ocular muscles involved and if there is superolateral extension. Patients that lacked superolateral extension were Page 6 successfully treated with the endoscopic approach. Endoscopic drainage has also been especially useful in cases of superiorly located abscesses. Here are a few good examples of orbital cellulitis. The image on the left demonstrates a nice view of a VOL 3 No 8 subperiosteal abscess (blue arrow) and proptosis (green AUGUST 2016 arrow). On the right, please note this patient has extensive sinus disease. There is obliteration of the left osteomeatal complex and extensive opacification of the left paranasal sinuses (red arrow).

Case Resolution This child was admitted to the hospital and begun on antibiotics. The agents used in this case were Ceftriaxone and Vancomycin. It is suspected that the cause of the orbital cellulitis was due to extension of the child’s sinus disease. As such, coverage for Streptococcus was initiated. However, given the high prevalence of Staphylococcal infection in our community and the child’s apparent facial cellulitis, anti- staphylococcal coverage was also indicated. Clindamycin would be appropriate, but given the extent of the child’s disease process Vancomycin was chosen instead. Pediatric Ophthalmology (Occuloplastic) and Pediatric Otolaryngology were both consulted. The child was taken the next day for surgical exploration/ drainage, which he underwent. Purulent material was obtained from the subperiosteal abscess but there was no indication of an orbital abscess. Fungal and anaerobic cultures were also sent. These cultures ultimately grew Streptococcus intermedius. Pediatric Neurosurgery was also consulted to review the imaging studies and they agreed that no epmyema was present. Pediatric Infectious Disease was consulted to provide appropriate antibiotic advice. The child had a PICC line placed and was discharged home with parenteral antibiotics for 3 weeks and oral antibiotics for 3 more weeks.

Teaching Points 1. Periorbital and orbital cellulitis are common complications of periorbital skin infection extension (for periorbital cellulitis) and extension of sinus disease (for orbital cellulitis). 2. Clinically, children with orbital cellulitis often have fever, appear more toxic, demonstrate proptosis, and often have painful ocular movements. However, the two clinical entities can be difficult to distinguish. 3. Imaging is often employed to differentiate between periorbital and orbital cellulitis. The most commonly utilized imaging modality is a contrast enhanced orbital CT scan. While utilizing ionizing radiation, the advantage to this modality is that it is quick, readily available, and can help determine the presence of an orbital or subperiosteal abscess, as well as other complications, such as cavernous sinus thrombosis, osteomyelitis, and the presence of sinusitis. 4. The presence of an orbital abscess is significant and prompt diagnosis is required, as this can be vision threatening. 5. Multi-subspecialty involvement is required to manage these children and prompt consultation is critical. 6. Periorbital infections can often be managed on an outpatient basis, typically with Augmentin. For more extensive disease, cinluding orbital and/or subperiosteal abscesses, IV antibiotics and drainage are indicated.

References 1. Knipe H and Di Muzio B. Orbital infection. radiopaedia.org 2. Lebedis CA, Sakai O. Nontraumatic orbital conditions: diagnosis with CT and MR imaging in the emergent setting. Radiographics. 2008;28 (6): 1741-53. 3. Sepahdari AR, Aakalu VK, Kapur R et-al. MRI of orbital cellulitis and orbital abscess: the role of diffusion-weighted imaging. AJR Am J Roentgenol. 2009;193 (3): W244-50. 4. Brugha RE, Abrahamson E. Ambulatory intravenous antibiotic therapy for children with preseptal cellulitis. Pediatr Emerg Care. 2012 Mar. 28 (3):226-8. 5. Liao JC, Harris GJ. Subperiosteal abscess of the orbit: evolving pathogens and the therapeutic protocol. Ophthalmology. 2015 Mar. 122 (3):639-47. 6. Seltz LB, Smith J, Durairaj VD, Enzenauer R, Todd J. Microbiology and antibiotic management of orbital cellulitis. Pediatrics. 2011 Mar. 127 (3):e566-72. 7. Wald ER. Periorbital and orbital infections. Pediatr Rev. 2004 Sep. 25(9):312-20. 8. Nageswaran S, Woods CR, Benjamin DK Jr, et al. Orbital cellulitis in children. Pediatr Infect Dis J 2006; 25:695. 9. Fatakis A and Guarisco JL. Management of superiorly based subperiosteal abscesses. Poster presentation. Tulane School of Medicine. 10. Coenraad S and Buwalda J. Surgical or medical management of subperiosteal orbital abscess in children: a critical appraisal of the literature. Rhinology. 2009. Mar;47(1):18-23. Page 7