Prevalence of the Onodi cell in the Polish adult population: an anatomical computed tomography study

BACKGROUND

Onodi cell is a posterior ethmoid air cell with the optic canal bulging into it; the common position of the bulge is into the sphenoid sinus, usually immediately posterior to the posterior ethmoid air cells. Variable pneumatisation patterns lead to various structures of lamellae and sinuses occasionally exposing important nerves and vessels, such as the optic and vidian nerves, internal carotid artery and cavernous sinus. In clinical practice, special imaging techniques are used to navigate through the paranasal sinuses and hence avoid injury to these structures. This study is aimed to determine the prevalence of the Onodi cell in the Polish population and compare it with other reported occurrences.

MATERIALS AND METHODS

A retrospective analysis of 296 computed tomography (CT) scans of patients treated in Krakow, Poland, using a Siemens Somatom Sensation 16 spiral CT scanner. No contrast medium was administered.

RESULTS

The Onodi cell was found in 31 out of the 296 patients, or approximately 10.5%, consistent with the majority of research reporting on Onodi variants. Additionally, there was one presentation of a bilateral Onodi cell in a male patient. No statistically significant difference was found between the male and female populations with a positive identification of the variant (p = 0.095, Chi2 test).

CONCLUSIONS

This study helped approximate the Onodi variant prevalence of 10.47%, falling within a commonly reported range 8-14%. This gives clinicians and surgeons a better understanding of this variant's structure and significance, and therefore an opportunity to improve treatment outcomes and research.

Extensive pneumatisation of the sphenoid bone - anatomical investigation of the recesses of the sphenoid sinuses and their clinical importance

BACKGROUND

There is a great variance between the extent of pneumatisation of the sphenoid sinuses that can reach beyond the body of the sphenoid bone. The purpose of this study was to find the frequency prevalence of the recesses of the sphenoid sinuses in Polish adult population.

MATERIALS AND METHODS

296 computed tomography (CT) scans of patients who did not present any pathology in the sphenoid sinuses were evaluated in this retrospective analysis. Spiral CT scanner - Siemens Somatom Sensation 16 - was used to glean the medical images. Standard procedure applied in the option Siemens CARE Dose 4D. No contrast medium was administered.

RESULTS

In the majority of the patients - 93.92%, the pneumatisation of the sphenoid sinuses expanded beyond the body of the sphenoid bone, hence there were recesses of the sinuses present. The most common variant was the prevalence of two recesses - 12.84% of the cases. The frequency prevalence of all the 17 recesses was only 0.34%. Amongst the uneven recesses present, the sphenoidal rostrum's recess (61.15% of the patients) and the inferior clinoid recess (56.42%) were the most common. Amongst the even recesses present, the lateral recess was prevalent in the majority (65.88%), whereas the posterior clinoid process' recess was the least common (9.8%).

CONCLUSIONS

Presence of the recesses might facilitate access to the cranial fossae, hence comprehensive evaluation of the sphenoid sinuses is of immense importance in order to avoid unnecessary drills through the hard bone, that could potentially damage the nearby neurovascular structures.

Bilateral ossification of the stylohyoid ligament

This paper presents the case of an adult male skull with bilateral ossification of the stylohyoid complex. The total length of the stylohyoid complex amounts to 62 mm on the left side and 65 mm on the right side. Visual inspection of the stylohyoid revealed the presence of callosities that are located on both stylohyoid complexes at nearly the same level. These sites are regarded as the ossified attachments of the stylohyoid ligaments to the corresponding styloid processes. The skull studied is an example of extreme development of the stylohyoid complex, which could cause severe pain and a restriction of head and neck movement.

Vascular system of the human spinal cord in the prenatal period: a dye injection and corrosion casting study

The vascularization of the spinal cord was investigated in 50 human fetuses aged from 10 to 28 gestational weeks using dye injection methods and corrosion casting accompanied by scanning electron microscopy. In the investigated period of fetal development, the general vascular architecture of the spinal cord, corresponding to that described postnatally, seemed to be already established. The observed changes included: (1) remodeling of the supplying (extrinsic) arterial branches, (2) transformation of the posterior anastomotic chain into two distinct posterior spinal arteries, and (3) development of the capillary networks in the gray and white matter. The remodeling of the radicular arteries supplying the spinal cord was accompanied by a decrease in their number and transition from regular to irregular distribution (appearance of intersegmental differences in their frequency). The anterior spinal artery and regular array of the central arteries were already present in the youngest fetuses examined, but the final remodeling of the posterior anastomotic chain into two posterior spinal arteries occurred between 15th and 20th week of fetal life indicating that the vascularization of the anterior region of the spinal cord in the investigated period of fetal life was more advanced as compared with that of the posterior region. The capillary network of the gray matter in the youngest fetuses had the form of discrete glomerular plexuses supplied by groups of central arteries and mainly vascularizing the anterior horns. Successively, the plexuses fused to form a continuous system along the anterior columns and the system expanded to fully vascularize the posterior horns. The white matter in the earlier fetal period seemed to be partially avascular, later the density of capillaries vascularizing those areas was still much lower than in the gray matter. The veins showed considerably greater variability than the arteries, as far as their topography and distribution was concerned. High tortuosity characterized the superficial veins, especially in the younger fetuses, although the degree of tortuosity differed even between individual fetuses. Only anterior spinal and central arteries were usually accompanied by their venous counterparts, the other veins seemed to have no regular topographical relations with the arteries.

[Changes in vascularization of sternocleidomastoid myocutaneous flaps]

Studies of variation in the vascularisation of the sternocleidomastoid myocutaneous flap. An investigation of vascularisation of the sternocleidomastoid myocutaneous flaps was conducted. The research was performed on human cadavers and after injection of arteries 40 myocutaneous flaps of sternocleidomastoid muscle were isolated. The experiment was performed to investigate the origin of the arteries vascularising the muscle and the area of skin, which were used to make the myocutaneous flaps. Changes are characteristic in the lower 2/3 parts of the muscle. These variables may exert an important influence of the outcome of reconstruction treatment in the case of the flaps used from the lower attachment of the muscle.

[Studies of the changes in vascularization of the myocutaneous flaps of the pectoralis major. Preliminary report]

The research in the vascularisation of myocutaneous flaps of the pectoralis major muscle was conducted on the human cadavers. After the injection of the arteries 20 myocutaneous flaps were created. The main artery which is the source of vascularization of this muscle is pectoralis branch of thoraco-acromial artery. The objective of the research was to find out the direction of run of this artery. The direction variability was defined. The variability in the run of the branch of the thoraco-acromial artery refers to the place of departure from the thoraco-acromial artery, does not influence usefulness of the pectoral major muscle in creating the myocutaneous flap, considering the constant pathway of run of the distal part of this artery. The results of our research was compared with the classical description of the vascularisation given by the creator of this flap as well as with the works of authors dealing with the same issue.

[Our experience with using nimodipine in the treatment of ischemic complications after subarachnoid hemorrhage]

On the basis of 50 patients treated for subarachnoid haemorrhage the authors report own experiences with the use of Nimotop for control of vasospasm caused by cerebral ischemia. All these patients were in grades III and IV of the Hunt-Hess scale. The studied patients with vasospasm and cerebral ischaemia were compared with patients similarly in grades III IV of this scale who were not given Nimotop. The analysis showed that patients treated with Nimotop were operated on earlier and had less evident neurological defect on discharge from the hospital.