Bilateral maxillary sinus hypoplasia and aplasia: radiological and clinical findings

Anatomical Changes in a Case with Asymmetrical Bilateral Maxillary Sinus Hypoplasia

Background and Objectives: The maxillary sinus hypoplasia (MSH) is an occasional variation of the maxilla, occurring either unilaterally or bilaterally. Previous studies dealing with MSH have not detailed the consequent anatomical changes of the maxilla and adjacent fossae. Materials and Methods: A 58-year-old female case was scanned in Cone Beam Computed Tomography and found to have asymmetrical bilateral MSH, who was then further evaluated anatomically. Results: The maxillary sinuses were hypoplastic and had mild mucosal thickenings. The orbital floors were curved. The uncinate process and the ethmoidal infundibulum were laterally displaced beneath the orbit floor. On each side, the lateral nasal wall protruded within the respective maxillary bone to reach above the vestibular cortical plate of the alveolar process. This expansion of the lateral nasal walls was limited to the premolar and first molar regions. The inferior turbinates were laterally curved. The perpendicular palatine plate was building a postero-lateral nasal wall in front of the pterygopalatine fossa. Conclusions: The classification systems of MSH should be detailed to indicate whether the normal uncinate process is medial or inferior to the orbit. The lateral expansion of the lateral nasal wall in MSH is limited to the anterior part of that wall. The laterally expanded nasal fossa could reach anterior to the pterygopalatine fossa in MSH. Seemingly, CBCT is a better tool than CT to evaluate the detailed anatomy of the modified anatomical structures in MSH; as such, it could be of help in a surgical approach.

Localization of orbit in patients with maxillary sinus hypoplasia: a radiological study

PURPOSE

We aimed to investigate the medial and inferior localization of orbit in patients with maxillary sinus hypoplasia using paranasal computerized tomography.

METHODS

We included 76 patients who had a hypoplastic maxillary sinus at least on one side, and 76 patients with normal maxillary sinuses (control group). To assess the localization of orbit, we measured the distances from middle meatal antrostomy point to medial border of orbital medial wall and to the lower border of orbital floor in all patients. We performed statistical comparisons between the groups.

RESULTS

Of 76 patients, 26 (34.2%) had unilateral and 50 (65.8%) had bilateral maxillary hypoplasia. Of 126 maxillary sinuses, 70 (55.6%) was type 1, 42 (33.3%) was type 2 and 14 (11.1%) was type 3 hypoplastic. The mean distance from antrostomy point to lamina papyracea was 4.36 ± 2.62 mm in the hypoplasia group, and 1.08 ± 1.7 mm in the control group. The mean distance from antrostomy point to orbital floor was 1.53 ± 1.73 mm in the hypoplasia group, and 1.87 ± 1.96 mm in the control group. Lamina papyracea showed a significant medial localization in the maxillary hypoplasia group as compared to the control group (p < 0.001).

CONCLUSION

The orbit has a medial localization in patients with maxillary sinus hypoplasia resulting in a higher complication risk during endoscopic sinus surgery.

Coexistence of frontal sinus hypoplasia with maxillary sinus hypoplasia: a radiological study

The goal of this study was to determine whether frontal sinus hypoplasia coexists with maxillary sinus hypoplasia. Analyzing paranasal CT scans retrospectively, we included 86 patients who had a hypoplastic maxillary sinus at least on one side and 80 patients with bilateral normal maxillary sinuses (control group). We classified hypoplastic maxillary sinuses using the classification system previously defined by Bolger et al. (Otolaryngol Head Neck Surg 103(5):759-765, 1990). We classified the frontal sinuses as aplastic, hypoplastic, medium-sized, and hyperplastic; as previously defined by Guerram et al. (Am J Phys Anthropol 154(4):621-627, 2014). We compared the presence of frontal sinus hypoplasia using Chi-square test between the groups. The mean age of the maxillary sinus group was 43.2 (range 18-84) years. Of 86 patients, 33 (38.4%) had unilateral and 53 (61.6%) had bilateral maxillary sinus hypoplasia. Of 139 maxillary sinuses totally included, 73 (52.5%) were type 1, 51 (36.7%) were type 2 and 15 (10.8%) were type 3 hypoplastic maxillary sinuses. Of 332 frontal sinuses totally included, 25 (7.5%) were aplastic, 32 (9.6%) were hypoplastic, 172 (51.9%) were medium-sized, and 103 (31%) were hyperplastic. Of 86 patients with a hypoplastic maxillary sinus at least on one side, 29 (33.7%) had a hypoplastic and/or aplastic frontal sinus, while 10 (12.5%) had a hypoplastic and/or aplastic frontal sinus at least on one side in control group. Incidence of frontal sinus hypoplasia and/or aplasia was significantly higher in patients with maxillary sinus hypoplasia compared to the patients with bilaterally normal maxillary sinuses (χ² = 10.384, P = 0.001). Maxillary sinus hypoplasia has a significantly higher coexistence with frontal sinus hypoplasia. This study may have an implication for anatomical studies about the development of the paranasal sinuses and paranasal sinus surgery as well as further morphological studies.

Combined Aplasia of Frontal and Sphenoid Sinuses with Hypoplasia of Ethmoid and Maxillary Sinuses

The paranasal sinuses are air filled spaces. The process of development of paranasal sinuses begins prenatally. The agenesis of paranasal sinuses in an unusual clinical condition and that is mainly confined to the frontal sinus unilaterally. Combined aplasia of multiple sinuses is extremely rare along with hypoplasia of other sinuses. Agenesis of sphenoid sinus is also rare in incidence. We report a case of a 54 years old female, who presented with complains of persistent headache with nasal blockage and found to have combined aplasia of bilateral frontal and sphenoid sinus with hypoplasia of bilateral maxillary and ethmoid sinus with unusual age of presentation. The findings were confirmed on non-contrast computed tomography scan of paranasal sinuses.

The role of the uncinate process in sinusitis aetiology: isolated agenesis versus maxillary sinus hypoplasia

OBJECTIVE

This study aimed to evaluate the clinical significance of maxillary sinus hypoplasia and isolated agenesis of the uncinate process in sinusitis aetiology.

METHODS

Three patients with isolated agenesis of the uncinate process and 27 patients with 43 maxillary sinus hypoplasia variations were recruited. The frequencies of sinusitis episodes and radiological findings were compared between patient subgroups.

RESULTS

In all, 23 type I maxillary sinus hypoplasia, 13 type II maxillary sinus hypoplasia and 7 type III maxillary sinus hypoplasia variations were detected. Patients with isolated agenesis of the uncinate process underwent antibiotic treatment an average of 7 times per year, whereas those with types I, II and III maxillary sinus hypoplasia were treated 1.57, 3.22, and 5.75 times per year, respectively, over a 5-year period. The antibiotic treatment frequency for patients with isolated agenesis of the uncinate process was significantly higher than for those with types I and II maxillary sinus hypoplasia.

CONCLUSION

Isolated agenesis of the uncinate process seems to play a stronger role than types I and II maxillary sinus hypoplasia in the pathophysiology of chronic sinusitis.

Unique canal communicating between both maxillary sinuses through the palatine recess with hypertrophy of sinuses

The result of an inappropriate growth of the jaws is in many cases related to abnormalities in the rest of the facial skeleton. We present a 21-year-old patient with a possibly unique anomaly of the maxillary sinus in skeletal class III dentofacial deformity. This anatomical variant has not to our knowledge been previously reported and all clinicians should be aware of it. It presented not only as hypertrophy of the sinuses but also as a communication between the two maxillary sinuses, and might be associated with a severe III class deformity with an extremely narrow maxilla. We describe this as a narrowed maxillary canal with no septum or membrane.

Maxillary sinus unilateral aplasia as an incidental finding following cone-beam computed (volumetric) tomography

This paper presents a case of maxillary sinus unilateral aplasia, an uncommon condition in adults, diagnosed as an incidental finding during cone-beam computed tomography (CBCT) examination for an endodontic case analysis. The patient was referred to a specialist endodontic practice for management of an upper right central incisor tooth. A CBCT scan was performed. The images of the left maxillary sinus showed a total lack of pneumatisation, prompting the diagnosis of aplasia. The patient's otolaryngologist was made aware of the findings. Clinical evaluation of volumetric images should be performed by an adequately trained dentist or radiologist so the maximum amount of information is gathered for the patient. This requires a systematic approach to ensure that no relevant information is missed and should include the paranasal sinuses and other surrounding structures as incidental findings can be observed during CBCT analysis.

Combined aplasia of sphenoid, frontal, and maxillary sinuses accompanied by ethmoid sinus hypoplasia

OBJECTIVE

To report the case of a woman who had combined aplasia of sphenoid, frontal, and maxillary sinuses accompanied by ethmoid sinus hypoplasia.

METHODS AND RESULTS

A 47-year-old woman presented with complaints of headache, nasal obstruction, and postnasal drainage. She had no previous history of either facial trauma or systemic diseases affecting the skeletal system. She had a history of functional endoscopic sinus surgery twice in an other institution. However, the surgeries did not significantly alter her symptoms. Coronal and axial computed tomographic scans of the nose and the paranasal sinuses showed poorly developed frontal, sphenoid sinuses, ethmoid cells, and very severe and profound hypoplasia (aplasia) of bilateral maxillary sinuses.

CONCLUSIONS

To our knowledge, this patient seems to be the first case having combined aplasias of the sphenoid, frontal, and maxillary sinuses with hypoplastic ethmoid cells without any systemic or skeletal disease.

Maxillary sinus aplasia

PURPOSE

A case of unilateral aplasia is reported. Associated anatomical anomalies and review of the literature is described, and a comparison with maxillary sinus hypoplasia is made.

PATIENT

A 40-year-old male was complaining of an esthetic "defect" in his face. There was an antero-posterior depression in the left infraorbital region. Computed tomography showed absence of the left maxillary antrum, uncinate process, and maxillary infundibulum. The ipsilateral orbit was increased in volume inferiorly, and the inferior margin was immediately adjacent to the root of the inferior turbinate. The left inferior and middle turbinate was hyperplastic. The nasal septum was a little dislocated to the ipsilateral side. There was no history of antecedent sinusitis or surgery, and no evidence of systemic disease. An appositional en bloc autogenous bone graft was placed on the left infraorbital depression.

CONCLUSIONS

With precise computed tomography assessments, a maxillary sinus hypoplasia or aplasia can be diagnosed and distinguished from other maxillary sinus anomalies, and may help the surgeon to plan his surgical procedure and identify the limits of dissection accordingly. The condition can also "cause" an esthetical deficit in the infraorbital/zygomatic region, which can be resolved with an appositional graft.