Antroscopy (synonym: maxillary sinusoscopy) is an invasive procedure in otolaryngology for precise endoscopic evaluation of the maxillary sinus. If there is a need for therapeutic intervention, the diagnostic component of maxillary sinus endoscopy can be augmented with minimally invasive surgical intervention as a treatment modality. Maxillary sinusoscopy plays an important role in the diagnosis of the presence of an inflammatory change in the maxillary sinus, also known as maxillary sinusitis. In addition to assessing an inflammatory infiltrate (focus of inflammation), maxillary sinusoscopy serves to exclude a neoplasia (new formation). However, it is not possible to determine macroscopically (“visible to the naked eye”) by means of maxillary sinus endoscopy whether the neoplasia present is benign (benign) or malignant (malignant). Nevertheless, the procedure is an important method in the detection of tumors in the maxillary sinus. A malignancy determination can be made in each case through a specimen excision. The cause of inflammation of the maxillary sinus may be difficult to determine, as there are many infectious causes of maxillary sinus inflammation. The following causes of maxillary sinusitis should be excluded during diagnosis:
- Rhinogenic sinusitis – this cause of maxillary sinusitis is due to the invasion of bacteria from the nasal area. Chronic infections can spread to the maxillary sinus and are a common cause of maxillary sinusitis.
- Hematogenous sinusitis – hematogenous sinusitis is due to bacteremia (blood work shows bacteria in the blood). The infection of origin may be relatively distant from the maxillary sinus, since general infections may spread either the pathogens or specific toxins through the blood. An example of a disease that may be associated with hematogenous spread and subsequent infection of the maxillary sinus is scarlet fever (Scarlatina).
- Odontogenic sinusitis – this form of sinusitis is due to a tooth-associated inflammatory process. Odontogenic infection represents the cause of about one-third of all maxillary sinusitis. Most often, the cause of inflammatory spread is based on an apical granuloma (superficial tissue neoplasm) of the first and second molar (first and second molars).
- Radicular cyst – a radicular cyst is a pathogenic (pathological) change based on an inflammatory process and associated with proliferation (increase) of the so-called Malassez epithelium (embryonic tissue).
- Infected follicular cyst
- Opening of the maxillary sinus during tooth extraction – with almost any mechanical stress on the gums, such as brushing teeth, bacteria can enter the bloodstream. However, if the immune system is intact, this does not pose a relevant threat. However, if a large amount of bacteria is carried into the maxillary sinus via a wound, this can lead to a massive inflammatory process.
- Periodontitis – periodontitis, which is a mostly chronic infection of the periodontium, is in very rare cases the origin of maxillary sinusitis, although a large part of the population suffers from this clinical picture.
- Intraosseous implants – implants anchored in the bone represent a foreign body for the body’s immune defenses. Due to this, it can come to the defense reaction and thus inflammation of the maxillary sinus.
Indications (areas of application)
- Chronic sinusitis maxillaris
- Suspected tumor in the maxillary sinus
- Suspected cyst in the maxillary sinus
Contraindications
A congenital bleeding tendency, which may be due to hemophilia (hereditary blood clotting disorder), for example, requires special precautions to avoid serious peri- or postoperative complications. If there is still a risk, the endoscopy must be canceled.
Before the endoscopy
- Additional diagnostic methods – although maxillary sinus endoscopy is a diagnostically valuable procedure, additional diagnostic imaging such as radiography or computed tomography (CT) should be performed before this invasive procedure is performed.
The operation procedure
Maxillary sinus endoscopy is a procedure in which a rigid endoscope (immovable rod that always contains a light guide and light source) can be used to examine the maxillary sinus and, if necessary, to obtain tissue samples in cases of suspicion. In addition, secretion samples can be obtained for cytological examination (cell examination) by maxillary sinus endoscopy. In addition to the diagnostic use of maxillary sinus endoscopy, therapeutic use of the procedure is also possible. Using the endoscope, minimally invasive targeted surgical removal of tissue masses can be performed. When performing maxillary sinus endoscopy and irrigation of the maxillary sinus, different access routes to the maxillary sinus can be distinguished:
- Lower nasal passage – to access the maxillary sinus via the lower nasal passage, puncture (piercing) of the lateral nasal wall must be performed. Depending on the goal of the endoscopy, the puncture can be performed using a trocar (medical instrument used to open a body cavity) or, when performing an irrigation, using a so-called Lichtwitz needle.
- Middle nasal passage – the middle nasal passage, through which a curved blunt cannula can be inserted, serves as another means of access to the maxillary sinus.
- Fossa canina – the fossa canina is a paired bone pit of the upper jaw. Through a mucosal incision and subsequent puncture of the fascial wall of the maxillary sinus (connective tissue component) can be reached.
After the reflection
After the maxillary sinus endoscopy, a tamponade of the maxillary sinus should be inserted by a gauze strip impregnated with ointment and removed after three days. Follow-up examination should be done after maxillary sinus endoscopy in any case.
Possible complications
- Nerve lesions – postoperative neuralgia (pain in the area supplied by a nerve) may occur after the procedure. In particular, the infraorbital nerve can be damaged by scarring of the nerve during scarring of the bone defect in the fossa canina, so this can lead to neuralgia. However, this complication can usually be consistently avoided by keeping the surgical area a sufficient distance from the nerve cords.
- Desensitivity of posterior teeth – the lack of sensitivity, especially in the area from the canine to the first molar, represents a clinically relevant complication. This complication can be precisely verified by performing a vitality test of the affected teeth. Despite the sensitivity deficits, the affected teeth are vital teeth because the vascular supply is intact. The reason for the complication is largely based on the anatomical conditions, as the nerve fibers are located directly under the mucosa of the maxillary sinus and are easily injured.
- Bleeding – the likelihood of bleeding occurring depends on how the procedure is performed. However, with minimally invasive surgery, the likelihood of bleeding is much higher than with diagnostic use of the procedure.
