DISCUSSION
A foreign body in the paranasal sinus is an uncommon clinical presentation. The condition is primarily associated with previous history of surgery, maxillofacial trauma, or dental procedures. The most common site of involvement is the maxillary sinus. Ethmoidal and sphenoid sinus foreign bodies are extremely rare. After diagnosis, the primary treatment modality is surgical retrieval, and the approach is typically along the course of penetration. Prior reviews have suggested treatment algorithms according to clinical scenario. Since foreign bodies in both symptomatic and asymptomatic cases may serve as a permanent source of irritation, it seemed reasonable to remove the object to prevent irritation and inflammation of the paranasal sinus. However, this case that was asymptomatic for 40 years emphasizes the importance of questioning and considering the true indications of surgical removal of foreign bodies in the paranasal sinus.
There are only a few cases that have reported foreign body impaction for more than 20 years.3,4 Lee et al.4reported maxillary sinus fungus ball development caused by retained foreign bodies and that was asymptomatic for 25 years and was successfully removed via a combined endoscopic and Caldwell-Luc approach. In addition, Kuhnel et al.3 reported an air gun pellet that had remained in the maxillary sinus for 50 years. Retained foreign bodies theoretically result in infectious complications, such as sinusitis.4,5 However, the actual clinical course of foreign body lodgment remains unclear. Prior reports of paranasal foreign bodies have identified pencils, paintbrushes, cues, chopsticks, ball pens, wire, and plastic sticks. Most cases consist of a metallic or plastic foreign body. A metallic foreign body comprised of a toxic element, such as a lead-containing bullet, prompts urgent retrieval due to the possibility of blood poisoning. To date, no reports have discussed the surgical necessity to treat other kinds of substances. Natural substances such as wood and plants are highly associated with infection, so prompt removal is indicated. In comparison, plastic foreign bodies do not tend to induce inflammation. There is currently no consensus for metallic foreign bodies other than those containing lead. We were not able to analyze the exact composites of the scissor blades but hypothesize that the materials differ from those, such as stainless steel, currently used to make scissors. Stainless steel consists of nickel or iron, and the advances in technology could have impacted the corrosivity.
Therefore, it is possible that a foreign body consisting of stainless steel might not directly cause critical inflammation, and immediate surgery may not be necessary. For example, cases that could wait and be kept under observation would include instances where the surgical removal approach is particularly difficult, if the foreign body is not in close proximity to neurovascular structures, or if the patient refuses surgery. Additionally, multiple fragments of foreign bodies may not be implicated for surgical removal. Therefore, surgeons must weigh benefits and harms and carefully discuss with the patient. If surgeons opt for an observation approach, there is a secondary issue about the relevant artifacts that may hinder precise evaluation when performing computed tomography or MRI. This must be also discussed with the patient to optimize treatment and outcomes.