OBJECTIVE: This study aimed to perform morphometric measurements of the pterygopalatine fossa (PPF), the transition zone to critical neurovascular structures. The second aim was to investigate the relationship between the volumes of the PPF and the paranasal sinuses and the effect of nasal septum deviation (NSD) types on all these measurements.
METHODS: We performed PPF\'s morphometry and all volume measurements on the CT images of 260 patients (130 male and 130 female, age range 18-79).
RESULTS: All volumetric measurements and the angle between foramen rotundum (FR) and pterygomaxillary fissure (PMF) were significantly higher in males than females. In contrast, the distance between sphenopalatine foramen (SPF) and PMF was considerably higher in females than in males. The PPF volume, the distance between the pterygoid canal (PC) and maxillary sinus, and the angle between FR and PMF were significantly higher on the right side than on the left. In contrast, the angle between PC and SPF and between greater palatine canal and PPF were considerably higher on the left side than on the right. The angle between PC and SPF decreased markedly with age. Only sphenoidal sinus volume was significantly smaller on the same side as the septal deviation. There was no correlation between PPF volume with maxillary and sphenoid sinus volumes from adjacent paranasal sinuses.
CONCLUSIONS: Volumetric and morphometric data obtained from PPF and paranasal sinuses can aid clinicians in diagnosing and treating patients by guiding them in selecting the right surgical approach or tools, especially in endoscopic procedures.

OBJECTIVE: Rhinosinusitis is one of the most common reasons for a visit to otolaryngology clinics. Some patients are candidates for sinus surgery. Infiltration of 1:100 000 adrenaline in the pterygopalatine fossa was studied, with the aim of evaluating the effect on bleeding in the surgical field.
METHODS: This double-blind clinical trial was conducted in 2021-2022 on 40 candidates for endoscopic sinus surgery. For each patient, one side of the pterygopalatine fossa was randomly selected to be infiltrated with a vasoconstrictor. Surgical field bleeding on each side was evaluated.
RESULTS: Blood loss was 35.8 ± 20.9 ml in the study group and 38.4 ± 23.7 ml for the control group, with no statistically significant difference between groups (p = 0.49). In addition, there was no difference between the two groups in terms of the surgical field based on Boezaart scores.
CONCLUSIONS: Although there are some recommendations on the usage of vasoconstrictors via the pterygopalatine foramen, debate remains.

To investigate the efficacy and safety of injecting onabotulinum toxin A (BTA) towards the sphenopalatine ganglion (SPG) using the MultiGuide® in patients with persistent idiopathic facial pain (PIFP).
This cross-over, exploratory study compared the injection of 25 units BTA versus placebo in patients who met modified ICDH-3 criteria for PIFP. Daily pain diaries were registered for a 4-week baseline, a 12-week follow-up after each injection, and an 8-week conceptual washout period in between. The primary efficacy endpoint was the change from baseline to weeks 5-8 in average pain intensity using a numeric rating scale. Adverse events were recorded.
Of 30 patients who were randomized to treatment, 29 were evaluable. In weeks 5-8, there was no statistically significant difference in average pain intensity between BTA versus placebo (0.00; 95% CI = -0.57 to 0.57) (P = 0.996). Following both BTA and placebo injections, five participants reported at least a 30% reduction in average pain during weeks 5-8 (P = 1.000). No serious adverse events were reported. Post-hoc analyses indicated a possible carry-over effect.
Injection of BTA toward the SPG with the MultiGuide® did not appear to provide a reduction in pain reduction at 5-8 weeks, although this finding may be influenced by a carry-over effect. The injection appears to otherwise be safe and well-tolerated in patients with PIFP.Trial Registration: The study protocol is registered in ClinicalTrial.gov (NCT03462290) and EUDRACT (number: 2017-002518-30).

This study describes the clinical anatomical topography and relationship of the terminal branches of the maxillary artery to the bony wall of the maxillary sinus in the pterygopalatine fossa (PPF) to estimate the bleeding risk during surgical interventions. Using contrasted computer tomography records, (i) the route of the maxillary artery in the infratemporal fossa, (ii) the number of the arteries in the critical PPF surgery plane, (iii) the diameter of the largest artery in the area and (iv) its relation to the posterior wall of the maxillary sinus were examined. Furthermore, measurements were extended with (v) the minerality of the bony posterior wall of the maxillary sinus on bone-window images. For statistical analyses Student\'s t- and Fisher-test were applied. 50 patients (n = 50, 100 cases including both sides) were examined in this study. The maxillary artery reached the pterygomaxillary fissure on the lateral side of the lateral pterygoid muscle in 56% of the cases (n = 32), in 37% (n = 23) on its medial side and in 7% (n = 4) on both sides. The number of arteries at the level of the Vidian canal in the PPF varied between 1 and 4 with a median of 2. The diameter of the biggest branch was 1.2-4.7 mm, the median diameter was 1.90 mm. In 41% (n = 30) of the cases the biggest artery directly contacted the posterior wall of the maxillary sinus, and the mineral density of the posterior wall was decreased in 14.3% (n = 12) of all investigated cases. The present description and statistical analysis of the vasculature of the PPF optimizes operative planning-like clip size or the type and direction of the surgical approach-in this hidden and deep head/neck region.

Objective The current study evaluated the complicated pathway of the posterior superior alveolar artery (PSAA) and measured the prevalence, diameter, and length of PSAA to the alveolar crests of molars using cone-beam computed tomography (CBCT). The study compared findings between dentate and edentulous patients grouped by their age. In addition, the study researched the presence of the septa. Methods One hundred and fifty CBCT scans of patients with ages ranging from 20 to 80 years were analyzed for the study. The measurements of PSAA were obtained from CBCT scans. Results The PSAA was detected on CBCT scans of 87.3% of participants. The majority course of PSAA was intraosseous (right side 53.3%, left side 63.3%). The diameter of PSAA was 1.30±0.42 mm on the right side and 1.19±0.40 mm on the left side. The length of PSAA to the alveolar crest of the third molar (A1) was 17.16±2.72 mm on the right side and 17.82±3.2 mm on the left side, to the first molar (M1) was 11.6±2.66 mm on the right side and 11.65±2.37 mm on the left side, and to second molar (M2) was 12.51±1.96 mm on the right side and 12.44±2.72 mm on the left side. There was no significant difference noticed between dentate and edentulous participant groups. Six percent (6%) of the scans showed the septa in the maxillary sinus. Conclusions The study showed that CBCT scans and their analysis help the clinician to make a better radiographic diagnosis and clinical application while using surgical procedures, such as implant placement and sinus lift.

BACKGROUND: Endoscopic endonasal approach to paramedian cranial base implies sacrifice of the nasal structures.
OBJECTIVE: The present study aimed to illustrate the anatomy and provide critical anatomical landmarks for the endoscopic prelacrimal recess approach (PLRA) to the paramedian middle cranial base.
METHODS: Anatomical dissections were performed in 10 cadaveric specimens.
RESULTS: Successful access to the paramedian middle cranial base was achieved in all dissections via the PLRA with the removal of the pterygoid process. For the dissection of the infratemporal fossa and pterygopalatine fossa, the buccal nerve and infraorbital neurovascular bundle can serve as important anatomic landmarks to identify the detailed structures. In the upper parapharyngeal space, the stylopharyngeal aponeurosis can present as anatomical barriers to protect the parapharyngeal segment of the internal carotid artery (PPICA); while the levator veli palatini muscle can be considered as a landmark to locate the PPICA. For the dissection of the Eustachian tube (ET), the isthmus of the ET and ET sulcus can serve as useful landmarks to identify the posterior genu of the ICA and horizontal segment of the petrous ICA respectively.
CONCLUSIONS: The PLRA to the paramedian middle cranial base is anatomically feasible and can facilitate preservation of the integrity of nasal structures. The buccal nerve, infraorbital neurovascular bundle, levator veli palatini muscle, stylopharyngeal aponeurosis, the isthmus of the ET, and ET sulcus can serve as critical anatomic landmarks in their respective region and may facilitate the application of this approach.

Robotic transmaxillary skull base surgery has been described using multiport systems. This cadaveric study investigates the feasibility of transmaxillary skull base surgery using a next-generation robot. An extended Caldwell-Luc antrostomy, measuring 3.3 cm by 4.0 cm, was performed in 15 min using a Kerrison rongeur and the robotic endoscope. A single-port, robotic system (da Vinci Sp®, Intuitive Surgical, Inc, Sunnyvale, CA, USA) was then deployed throught the extended Caldwell-Luc approach and provided sufficient reach, visualization, and maneuverability to work within the pterygopalatine fossa (PPF) and the infratemporal fossa (ITF) using three surgical instruments. The ITF dissection was easiest with two instruments using the third instrument to retract the muscles of mastication. This study demonstrates the feasibility of single-port robotic transmaxillary approaches to the lateral ITF. Using a single-port robotic system, the operating surgeon can for the first time work in the PPF and ITF using two functional arms for tumor dissection and a third to retract.

OBJECTIVE: To investigate the anatomical characteristics and clinical implications of the pterygovaginal artery (PtVA), a recurrent branch from the distal internal maxillary artery (IMA), which courses through the pterygovaginal canal that connects the pterygopalatine fossa and nasopharynx.
METHODS: Eighty-two patients with 90 sides of cone-beam computed tomography (CBCT) reconstructed from rotational angiography of the external or common carotid artery with a field of view covering the pterygopalatine fossa were retrospectively reviewed. The origin from the IMA, branching type, distribution, and anastomoses was evaluated. The underlying lesions were 36 hypervascular lesions with possible supply from PtVA (17 cavernous sinus arteriovenous fistulas (AVFs), 6 anterior condylar AVFs, and 13 nasopharyngeal, parasellar, or paraclival tumors) and 46 other diseases.
RESULTS: PtVA was identified in 75 sides (83%). It originated from the pterygopalatine segment of the IMA in 45 sides (60%) and from the pterygoid segment in 30 sides (40%). It arose independently (77%), sharing the common trunk with the Vidian artery (15%) or with other branches. It ran posteromedially through the pterygovaginal canal to supply the mucosa over the nasopharyngeal roof, the choanae, and the pharyngeal ostium of the eustachian tube. It anastomosed with the ascending pharyngeal artery (n=37), the accessory meningeal artery (n=7), and the mandibular artery from the petrous internal carotid artery (n=2). It served as a feeder of osseous AVFs and skull base tumors.
CONCLUSIONS: PtVA was often identified by CBCT even in normal anatomy. Its detailed angio-anatomy could be evaluated in the presence of parasellar or paraclival hypervascular lesions.

OBJECTIVE: This study aimed to locate the inferior end (Pti) and the superior end (Pts) of pterygomaxillary junction (PMJ) relative to anterior nasal spine (ANS) so as to provide references for pterygomaxillary separation.
METHODS: The study was based on CBCT images of 109 Chinese patients. We projected Pti and Pts to the frontal plane and measured the distance as well as the positional relationship between the projection points and ANS via three-dimensional reconstruction image.
RESULTS: On average, the ANS was 5.18 mm above the Pti and the horizontal distance between the Pti and ANS was 21.86 mm. The horizontal and vertical distances between Pts and ANS was 20.41 mm and 10.91 mm, respectively. The vertical height of PMJ was 16.09 mm. Scatter plots diagrammatic centered on ANS showed that 73% (160/218) Pti and 64% (140/218) Pts appeared in a 45° fan shape ranged from 20 to 25 mm radius in bilateral inferior and superior quadrant, respectively. There was no significant difference in the distance between both sides (P > 0.05).
CONCLUSIONS: During the pterygomaxillary disjunction, it exists a risk of injuring neurovascular bundle of the pterygopalatine fossa 16.09 mm above the lowest border of the pterygomaxillary junction. The region within a 45° fan shape ranged in 20-25 mm radius in inferior quadrant centered on ANS might be suitable for the osteotome position. The positional relationship especially between the ANS and Pti found in this study provides a reference for surgeons during pterygomaxillary disjunction.

UNASSIGNED: Transnasal sphenopalatine ganglion block is a commonly used approach for treatment of a variety of headache disorders. However, no standard technique has yet been defined for this less invasive approach. In this study, our aim was to investigate morphometric and anatomical features of the sphenopalatine foramen, and to describe a more efficient approach for transnasal sphenopalatine ganglion block.
UNASSIGNED: The present study was designed retrospectively. Ten cadaver semi- heads and 18 adult dry skulls (28 samples totally) were included in the study. The distances between the sphenopalatine foramen and palatum durum, and also between the sphenopalatine foramen and the spina nasalis anterior, angle of elevation of the sphenopalatine foramen from palatum durum, and the length and width of the sphenopalatine foramen were measured.
UNASSIGNED: The mean width and length of the foramen were 3.79±0.35 and 6.44±0.94 mm, respectively. The mean distance between the palatum durum and the sphenopalatine foramen was 15.58±1.68 mm. The mean angle of elevation of the sphenopalatine foramen from the palatum durum was 26.10±3.97 degrees. The mean distance between the sphenopalatine foramen and the anterior nasal spine was 52.90±2.98 mm.
UNASSIGNED: In the transnasal sphenopalatine block, we suggest advancement of nasal applicator through superolateral direction for approximately 5.3 cm, and at an angle of about 26° from the nasal base..
UNASSIGNED: Transnazal sfenopalatin gangliyon bloku, baş ağrısı hastalıklarının tedavisi için yaygın olarak kullanılan bir tedavi yöntemidir. Ancak bu noninvaziv teknik için henüz standart bir teknik tanımlanmamıştır. Bu çalışmada amacımız, sfenopalatin foramenlerin morfometrik ve anatomik özelliklerini araştırmak ve transnazal sfenopalatin gangliyon bloku için daha etkili bir yaklaşım ortaya koymaktır.
UNASSIGNED: Bu çalışma retrospektif olarak dizayn edilmiştir. Çalışmaya 10 adet yarım kadavra kafası ve 18 erişkin kuru kafatası olmak üzere toplam 28 örnek dahil edildi. Sfenopalatin foramen ve palatum durum arasındaki mesafe, sfenopalatin foramen ve spina nasalis anterior arasındaki mesafe, palatin durumundan sfenopalatin foramenlerin yükselme açısı ve sfenopalatin foramenlerin uzunluğu ve genişliği ölçüldü.
UNASSIGNED: Foramenlerin ortalama genişliği ve uzunluğu sırasıyla 3,79±0,35 ve 6,44±0,94 mm idi. Palatum durum ve sfenopalatin foramenler arasındaki ortalama mesafe 15,58±1,68, sfenopalatin foramenlerin palatum durumdan yükselme açısı ortalama 26,10°±3,97, sfenopalatin foramenlerin anterior nazal spinadan ortalama uzaklığı 52,90±2,98 mm idi.
UNASSIGNED: Transnazal sfenopalatin blok uygulamasında kullanılan nazal aplikatörün süpero-lateral yönde ortalama 5,3 cm, burun tabanından ortalanma 26° açı yapacak şekilde ilerletilerek uygulanmasını tavsiye ediyoruz.