More to it than meets the eye: a case of retained intraorbital foreign body removed using transcutaneous orbital endoscopic surgery

Abstract

The possibility of a retained foreign body should always be considered when a patient presents with a history of orbital trauma, especially when the patient is unresponsive or temporarily responsive to treatment. Not all cases of retained foreign body present with decreased vision or restricted mobility or fever. The entry wound is also not apparent on examination in all cases. In summary, meticulous history-taking, thorough examination, high index of suspicion along with a low threshold for imaging studies are essential to make a timely diagnosis of a retained intraorbital foreign body. The prompt removal with the appropriate approach may not only save the eye but also the life of the patient.

Background

Intraorbital foreign bodies are not a very common occurrence. Regardless of the best efforts, these maybe overlooked and the diagnosis maybe missed. It may also occur that a part of the foreign body may be retained. The importance of this cannot be highlighted enough as these scenarios may soon cause loss of vision or worse, can be life-threatening. Here, we present a case report of a retained orbital foreign body, missed initially on radiological examination and surgical exploration, and eventually removed using a novel technique.

Case presentation

A 23-year-old, otherwise healthy woman, had a history of blunt force trauma over the left cheek by a wooden stick in June 2017. She developed generalised swelling over the left cheek and a 1 cm laceration just below the left lower eyelid. She did not have any diminution of vision and hence did not approach a medical facility immediately. A few days later she developed purulent discharge from the laceration and then approached a primary healthcare. An incision and drainage of the wound was done. A small wooden chip was found during the procedure and was removed. The patient was then discharged on oral antibiotics. The wound was quiet till the antibiotics continued and then again started discharging. A repeat incision and drainage was done with postoperative antibiotics. This cycle was repeated for a total of four times. The patient eventually developed a granuloma over the site of the laceration and painful mouth opening. The patient was then referred to us for further management.

On examination, the patient had a 1×1 cm granuloma just below the left lower eyelid, swelling and mild tenderness over the left zygomatic region and purulent discharge from the granuloma on mouth opening. Ophthalmological examination was suggestive of a vision of 6/60 in the left eye, no restriction of movement and no evidence of relative afferent pupillary defect. The fundus examination showed clear media and normal optic disc.

Investigations

A local ultrasonography was done which was suggestive of a 1.3×0.8 cm subcutaneous collection without any bony breach or erosion or intraorbital extension. A CT scan of orbit +paranasal sinuses with contrast was then advised. This was suggestive of a mildly enhancing ill-defined soft tissue in the left infero-lateral region of orbit, extending into the left infratemporal fossa with sinus tract formation (~4 cms). Also noted was focal erosion of the inferolateral wall of the left orbit and the adjacent lateral wall of maxillary sinus, all suggestive of secondary osteomyelitis. There was no evidence of foreign body (figure 1).

Figure 1.

CT scan showing no evidence of foreign body.

The patient was posted for wound exploration and bone sampling for culture-sensitivity guided antibiotic therapy. Three pieces of retained wooden foreign body largest 20×2 mm were recovered from the sinus tract. The patient was given culture sensitive intravenous antibiotics and then discharged on oral ciprofloxacin. The patient returned after 1 month with a granuloma again at the same site and blurring of vision.

This time, the radiologists were informed of a high possibility of a retained wooden foreign body and a repeat CT scan was performed. It reported a 34×3 mm foreign body in the left extraconal compartment of the orbit extending into the left temporalis muscle (figure 2).

Figure 2.

CT scan showing foreign body.

Treatment

The patient was posted for removal of retained foreign body by the transcutaneous endoscopic orbital surgery. An oculoplastic surgeon was present to help prevent injury to the eyeball.

Surgical technique

A 1 cm bone deep incision was made over left infraorbital granuloma, incising the periostium over the zygoma. The periostium was then elevated using a Lempert’s elevator extending along floor of the orbit under endoscopic guidance. The orbital periostium was then incised using a sickle knife. Unhealthy tissue and purulent discharge was visualised while dissecting the fat. Two pieces of wooden stick were visualised and removed (33×6 mm and 39×8 mm) using a small Blakesley forceps (figure 3). The cavity was thoroughly inspected and due to the endoscope multiple fragments of wood, not visible to the naked eye, were identified and removed. A betadine saline irrigation was given. A forced duction test was performed which indicated complete range of movement. The external wound was sutured and a temporary tarsorrhaphy was performed to prevent the formation of an ectropion.

Figure 3.

Foreign body wooden stick.

Outcome and follow-up

Patient was administered intravenous ciprofloxacin 500 mg two times a day for 7 days. Sutures were removed and she was discharged. Postoperatively, the blurring of vision resolved, visual acuity was 6/9, and the range of movement was complete in all directions, the wound healed. There were no signs and symptoms of osteomyelitis. The recovery was uneventful and the patient is under follow-up until (figure 4).

Figure 4.

(A) Preoperative picture showing granuloma and discharging sinus. (B) Postoperative picture showing healed wound.

Discussion

Most cases of orbital and periorbital trauma are self-evident and the patients are successfully diagnosed. There are number of reports of foreign body being extracted from the orbit and infratemporal fossa secondary to external trauma. Unfortunately, in some cases, foreign bodies are retained in spite of initial wound exploration and have had to be removed later following complications. The retention period usually ranges from a few days to many months.^{1 2} The most frequently encountered foreign bodies are usually metallic objects and glass.³ As these are inorganic, they incite little inflammatory reaction. On the contrary, organic foreign bodies like wood lead to an acute inflammatory reaction and dire consequences if not removed. These include decreased vision, motility disturbance, orbital abscess, meningitis or even death. Also, on account of its porous nature, wood has a very high tendency to fragment and to be secondarily contaminated by microbes. This necessitates its urgent removal.

A history of non-resolving pain or discomfort, development of proptosis, diplopia or vision loss, fistula formation should alert the treating physician to a possibility of a retained foreign body. The entry wound for an orbital foreign body may not necessarily be apparent. A thorough examination should be carried out with emphasis to examination of the conjunctival fornix and elicitation of any local tenderness. No imaging modality, be it a CT or MRI, can detect a wooden foreign body with 100% sensitivity.⁴ Even though a CT is the imaging modality of choice for a retained intraorbital foreign body, very large wooden foreign bodies may also be missed or appear as intraorbital air without proper windowing.⁵ Even in cases of radiopaque foreign bodies, many a times, more fragments or foreign bodies are retrieved during surgery than are apparent on the scans. Thus, it is of prime importance to convey to the radiologist the mode of injury and the nature of the suspected foreign body. In our case, a CT was repeated after communication with the radiologists and the subsequent CT scan exposed the retained foreign body.

Lateral orbitotomy is one of the most commonly used approaches to the orbit for pathologies lying lateral to the optic nerve. This procedure, however, is not without its complications, which include transient impairment of eyeball movement, visual impairment and a tonic pupil. It also includes removal of bone to ensure adequate exposure, increasing the morbidity.

Transcutaneous orbital endoscopic surgery is a novel technique to manage lesions which lie lateral to the optic nerve.⁶ It offers the advantages of the endoscope in the form of better illumination with a wide-angle view and improved magnification of the surgical field. This allows for a smaller incision than required for lateral orbitotomy and precludes the need for bone removal. The rigid nature of the endoscope allows it to function as a ‘retractor’ for the surperficial tissues in order to reach a deeper plane. Transcutaneous orbital endoscopic surgery is now an established procedure for abscess drainage and taking biopsies. We have taken it one step further and successfully used it for foreign body removal.

Patient’s perspective.

I had a history of blunt force trauma over my left cheek in June 2017. I did not give importance to it and neglected it. A week later, I noticed discharge from my cheek wound and visited a hospital close to my home. The doctor there admitted me in their hospital and performed a minor surgery and removed a small wooden chip from my cheek wound. I could go home with medication. All went well with medication. Once my medicines got over I again developed discharge from my cheek wound. I was again taken for surgery. This continued several times until I developed a granuloma over the wound and also got painful mouth opening. They referred me to this hospital. Here, the doctor took a detailed history and after thorough examination told me that I need to do a CT scan. I got my CT scan done. My doctors went through the scan and said no foreign body was seen but told me that I will be taken for surgery to see my wound and also look for any residue of foreign body. I underwent the surgery, three pieces of wooden foreign body was removed from my wound. I was given discharge from hospital and went home. A month later again I developed swelling over the same site but with slight blurring of vision. I was very sad and went back to my doctor. This time my doctor was very sure of the foreign body and took me to the radiologist and told them about the certainty. I got my scan repeated, to my surprise my doctors said that the CT scan showed a huge foreign body inside. Again I was taken for surgery; I had strong faith in my doctors. When I woke up from surgery my doctors showed me the 7 cm long wooden stick which was removed from my wound. This time my doctors assured me that my wound will heal well. A week later stich was removed my wound looked good. Couples of months has passed, my wound has healed completely. I’m really grateful to all my doctors whose insight and prompt decision helped me from losing my vision.

Learning points.

• In literature, there are reports of silent intraorbital foreign body later presenting with complications.

• A history of non-resolving wound should alert the treating physician to a possibility of a retained foreign body.

• Meticulous history-taking, thorough examination, high index of suspicion with a low threshold for imaging studies are essential to make a timely diagnosis of a retained intraorbital foreign body.

• The prompt removal with the appropriate approach may not only save the eye but also the life of the patient.