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The superficial middle cerebral vein (SMCV) commonly drains in the cavernous sinus. Its different drainage variants include preserved segments of the primitive tentorial sinus. In any of these variants, the terminal venous segment of SMCV passes on the base of the skull. The archived computed tomography angiograms of a 58-year-old female case were documented anatomically. On the left side was found the sinus of the lesser sphenoidal wing converging with the middle meningeal vein to form a venous channel located within the Sylvian fissure at 4 mm laterally to the cavernous sinus and trigeminal cavum. That venous channel was thus termed the 'laterocavernous vein'. It drained posteriorly within the superior petrosal sinus. This aberrant vein could interfere unpleasantly with pterional neurosurgical approaches for the Sylvian fissure, cavernous sinus or trigeminal ganglion.

The persisting primitive olfactory artery (PPOA) is a rare anatomic variation of the anterior cerebral artery (ACA), being encountered in less than 1% of cases. Different morphological types were reported previously. In type 3, only once reported previously, the PPOA gives off two branches, a nasal one which courses in the olfactory sulcus to supply the territory of the anterior ethmoidal artery, and the callosomarginal artery. It is reported here a combination of rare anatomic variants found in a 71-year-old male patient investigated by computed tomography angiography. A left PPOA left the A1 segment of the ACA and was classified as subtype 3b, as its branches were the nasal one and a frontal trunk, not the callosomarginal artery. That PPOA had a characteristic hairpin turn applied on the anterior fossa floor. The ACA continued as azygos pericallosal artery, which is also a rare finding. As the nasal branch of the PPOA and its hairpin turn is closely related to the anterior fossa floor, such variant should be carefully documented when combined approaches of the skull base are planned by rhinologists and neurosurgeons.

This study aimed to investigate the prevalence of tympanic plate (TP) pneumatisation as well as the various potential patterns. A retrospective study involving the archived Cone-Beam Computed Tomography (CBCT) files of 70 patients was performed to investigate anatomical variations of TP pneumatisation. Forty-eight TPs were found to be non-pneumatised, while 92 were found to contain at least peritubal air cells. Twenty patients (28.5%) did not present any variety of TP pneumatisation, while 36 patients (51.4%) exhibited a symmetrical pattern of pneumatisation. Aside from those patients who lacked TP pneumatisation, the peritubal pneumatisation pattern was found to be the most common. Further, bilateral symmetry was found to occur in more than half of all cases. CBCT is a powerful diagnostic tool, although appropriate knowledge of the anatomical possibilities remains mandatory for adequate surgical planning.

The external carotid artery (ECA) normally bifurcates terminally with the superficial temporal artery (STA) and the maxillary artery (MA). From the horizontally coursing, mandibular segment of the MA leaves the middle meningeal artery (MMA). We hereby report a previously unknown anatomic possibility, incidentally found during an angio-CT scan in an adult female patient. Unilaterally, the ECA was terminally trifurcated, sending off the MA, STA, and MMA. On that side, the mandibular segment of the MA had a gamma-loop and the contralateral one had a U-loop; both these loops were inferior to the lateral pterygoid muscle, closely approaching the respective lingula of the mandible. These findings are relevant during surgery of the parotid gland and infratemporal fossa, approaches of the MMA, and inferior alveolar nerve blocks. The modified origin of the MMA could be explained by an altered development of the primitive stapedial artery.

Nasal anatomic variations are relevant during nasal surgical and endoscopic procedures. The extent of imaging methods, such as the cone beam computed tomography (CBCT), allows a better characterization of such peculiar anatomic traits. The bifid inferior turbinate (BIT) is a rare finding, being previously reported less than ten times. It was found and described on CT scans of patients, being usually associated with the absence of the uncinate process (UP). We hereby report for the first time a bilateral true BIT which differs from the previously reported BITs by the fact that the UPs were present and the bifidity was oriented laterally. In the light of this new find, we consider that the variant resulted from UP displacement should be regarded as a false bifid, or double, inferior turbinate. Bifidity of the inferior turbinate was not previously evaluated in CBCT, as well as in three-dimensional volume renderizations. So, CBCT proves as an efficient tool to investigate prevalence of rare anatomical variants. Noteworthy, CT studies of patients on a case-by-case basis allows a better performance of surgical and endoscopic procedures.

The pneumatizations surrounding the pterygopalatine fossa (PPF) and closely related to the sphenopalatine foramen are anatomically variable. During the assessment of a cone beam computed tomography of a 64-year-old male patient, we found bilaterally a previously unreported anatomic variant. This was represented by a lateral or pterygopalatine recess (PPR) of the superior nasal meatus which extended in the anterior wall of the PPF and protruded within the maxillary sinus to determine a maxillary bulla. The PPR was antero-superior to the sphenopalatine foramen. Additionally were found a right nasal septal deviation, seemingly compensated by a left middle concha bullosa and a left prominent ethmoidal bulla. The superior turbinates were also pneumatized. Such anatomic variants related to the pterygopalatine angle of the maxillary sinus should be explored prior to surgical or endoscopic procedures which target the maxillary sinus, the pterygopalatine fossa, or the skull base.

The infraorbital canal (IOC) normally courses above the maxillary sinus in the orbit floor. During a retrospective study of cone beam computed tomography (CBCT) scans, we found a previously unknown variant of the IOC. The IOCs were absent, being replaced by lateroantral canals coursing around and not above the maxillary sinus to open at infraorbital foramina which were located above the second upper premolar teeth. On coronal multiplanar reconstructions, the lateroantral canals were located anatomically at the outer limit of the zygomatic recess of each maxillary sinus, while the upper wall of the sinus was devoid of any canal. Such rare variant should be kept in mind by dental practitioners and surgeons, as it can determine modifications of common procedures. In this regard, the anatomy of maxilla, as well as mandible, should be evaluated in CBCT on a case-by-case basis.

The superior cerebellar artery (SCA) is, perhaps, the most anatomically constant cerebellar artery which, in its lateral pontomesencephalic course, is crossed above by the trochlear nerve (CNIV). The SCA may determine, as an offending vessel, CNIV compression and superior oblique myokymia and thus surgical decompression may be indicated. In this regard an accurate knowledge of the variational possibilities of the SCA–CNIV is needed. Such rare neurovascular variants are reported here. The variables are determined by the length of the SCA, and the course of the CNIV as referred to the rostral (RT) and caudal (CT) trunks of the SCA. The CNIV may be pinched between the origins of the RT and CT, may pass above the RT or the SCA main trunk, and even between the primary branches of the RT. The CNIV was found compressed between the RT and the brainstem. Perhaps the most spectacular variation was a CNIV coursing through an arterial ring formed by the RT and CT which were anastomosed distally to the CNIV. The possibilities of neurovascular relations between the CNIV and the SCA should be considered when CNIV palsy, or surgical decompression, are estimated.

The anatomy of the pterygopalatine fossa keeps a traditional level and is viewed as constant, even though a series of structures neighboring the fossa are known to present individual variations. We aimed to evaluate on 3D volume renderizations the anatomical variables of the pterygopalatine fossa, as related to the variable pneumatization patterns of the bones surrounding the fossa. The study was performed retrospectively on cone beam computed tomography (CBCT) scans of 100 patients. The pterygopalatine fossa was divided into an upper (orbital) and a lower (pterygomaxillary) floor; the medial compartment of the orbital floor lodges the pterygopalatine ganglion. The pneumatization patterns of the pterygopalatine fossa orbital floor walls were variable: (a) the posterior wall pneumatization pattern was determined in 89.5 % by recesses of the sphenoidal sinus related to the maxillary nerve and pterygoid canals; (b) the upper continuation of the pterygopalatine fossa with the orbital apex was narrowed in 79.5 % by ethmoid air cells and/or a maxillary recess of the sphenoidal sinus; (c) according to its pneumatization pattern, the anterior wall of the pterygopalatine fossa was a maxillary (40.5 %), maxillo-ethmoidal (46.5 %), or maxillo-sphenoidal (13 %) wall. The logistic regression models showed that the maxillo-ethmoidal type of pterygopalatine fossa anterior wall was significantly associated with a sphenoidal sinus only expanded above the pterygoid canal and a spheno-ethmoidal upper wall. The pterygopalatine fossa viewed as an intersinus space is related to variable pneumatization patterns which can be accurately identified by CBCT and 3DVR studies, for anatomic and preoperatory purposes.

The intrinsic lingual neural interconnections are overlooked. It was hypothesized that intralingual anatomically well defined anastomoses interconnect the somatic and autonomic neural systems of the tongue. It was thus aimed to evaluate the intralingual neural scaffold in human tongues. Human tongue samples (ten adult and one pediatric) were microdissected (4.5 magnification). In the interstitium between the genioglossus and hyoglossus muscles, the branches of the lingual nerve (LN) and the medial trunk of the hypoglossal nerve (HN) had a layered disposition of the outer and inner side, respectively, of the lingual artery with its periarterial plexus. Anastomoses of these three distinctive neural suppliers of tongue were recorded, as also were those of the LN with the lateral trunk of the HN and the anastomoses between successive terminal branches of the LN. Successive ansae linguales were joining the LN branches and the medial trunk of the HN. The intrinsic neural system of the tongue supports integrative functions and allows a better retrospective understanding of various experimental studies. The topographical pattern is useful for an accurate diagnosis of intralingual nerves on microscopic slides.

Even though the doubled foramen rotundum (FR) can be identified once within the literature, there are no details of the contents at that level. We present here an anatomical case demonstrating the maxillary nerve (MN) duplication at the level of an unilateral doubled FR: the accessory nervous trunk of the MN separately left the trigeminal ganglion on the outer side of the MN main trunk and coursed beneath the main trunk of the MN canal, within the sphenoidal greater wing, to join infero-medially that main trunk at the entrance in the pterygopalatine fossa. Overall, the MN appeared as fenestrated, with a thin bony plate separating the two cords of the nerve traversing the skull base. Previously undocumented, the MN duplication may interfere with various surgical exposures interfering with the foramen rotundum and may explain atypical sensory syndromes and functional impairment during skull base trauma or anesthesia.

In an aged human female cadaver a left accessory aberrant colic artery (LAACA) was observed and studied. It originated from the superior mesenteric artery at 3 cm proximal to the middle colic artery, at the inferior border of pancreas, passing over Treitz's muscle and continued covered by the superior duodenal fold where it crossed the inferior mesenteric vein. Further, it continued with a satellite vein anterior to the left renal vein and the anterior branch of the renal artery. The LAACA divided into an ascending branch and a descending one, anastomosed with the middle colic and proper left colic arteries; between its two primary branches and the splenic flexure of colon, a hypovascular area was observed. The surgical relevance of the LAACA detailed anatomy mainly relates to specific procedures performed in left colectomies and nephrectomies.