Comparison of colour difference formulas to best distinguish resected areas of malignant brain tumours from their background using 5-aminolevulinic acid fluorescence.

BACKGROUND: Fluorescence-guided surgery (FGS) with 5-aminolevulinic acid (5-ALA) has been proven to assist neurosurgeons to achieve a more complete brain tumour resection. However, 5-ALA-guided surgery is limited since it is often difficult to distinguish the colour difference between the resected areas of malignant brain tumours from their background. Our aim was to evaluate which colour difference formula was optimal to distinguish between malignant brain tumours and the background healthy tissue using 5-ALA fluorescence. MATERIALS AND METHODS: Thirty-seven patients with a primary or secondary malignant brain tumour ingested 5-ALA before the surgery. A 400 nm light was used to excite the fluorescence. Surgical videos were recorded for all the patients and a total of 183 samples were obtained from the fluorescent areas and their respective backgrounds. Three colour differences formulas - contrast ratio (CR), CIELab (ΔE*) and CIEDE2000 - were applied to the videos and compared using hot-cold maps. Baseline demographics, the tumour's location, the tumour's side, and tumour's World Health Organization (WHO) grade was also analysed for correlations relating to the fluorescence. Chi-square and the Student's t-test were used for univariate relations. The three channels of the CIELAB colour space (L*, a* and b*) were analysed together and separately (since L* of fluorescent areas was significantly higher than the background). RESULTS: ΔE* resulted in good discrimination of a* and b*, and moderate but acceptable discrimination of L*. CIEDE2000 distinguished differences in a* and b*, although not in L*. The CR distinguished only L*, whereas the probability of discriminating a* and b* channels failed. Neither age, sex, tumour location, tumour size nor the WHO grade influenced the a*, b* and L* colour values (p > 0.05). Colour differences measured by ΔE* and CIEDE2000 correlated together (r = 0.99, p < 0.01), whereas CR correlated only with ΔE* (r = 0.21, p = 0.01) but not with CIEDE2000 (r = 0.07, p = 0.32). CONCLUSIONS: ΔE* obtained the best colour discrimination between the resected areas of malignant brain tumours and the background when compared to CR and CIEDE2000. Therefore, ΔE* may be the best formula to help neurosurgeons distinguish the colour differences when operating malignant brain tumours with 5-ALA fluorescence.

Tractography-guided surgery of brain tumours: what is the best method to outline the corticospinal tract?

BACKGROUND: Diffusion tensor imaging (DTI) is the imaging technique used in vivo to visualise white matter pathways. The cortico-spinal tract (CST) belongs to one of the most often delineated tracts preoperatively, although the optimal DTI method has not been established yet. Considering that various regions of interests (ROIs) could be selected, the reproducibility of CST tracking among different centres is low. We aimed to select the most reliable tractography method for outlining the CST for neurosurgeons. MATERIALS AND METHODS: Our prospective study consisted of 32 patients (11 males, 21 females) with a brain tumour of various locations. DTI and T1-weighed image series were acquired prior to the surgery. To draw the CST, the posterior limb of the internal capsule (PLIC) and the cerebral peduncle (CP) were defined as two main ROIs. Together with these main ROIs, another four cortical endpoints were selected: the frontal lobe (FL), the supplementary motor area (SMA), the precentral gyrus (PCG) and the postcentral gyrus (POCG). Based on these ROIs, we composed ten virtual CSTs in DSI Studio. The fractional anisotropy, the mean diffusivity, the tracts' volume, the length and the number were compared between all the CSTs. The degree of the CST infiltration, tumour size, the patients' sex and age were examined. RESULTS: Significant differences in the number of tracts and their volume were observed when the PLIC or the CP stood as a single ROI comparing with the two- ROI method (all p < 0.05). The mean CST volume was 40054U (SD ± 12874) and the number of fibres was 259.3 (SD ± 87.3) when the PLIC was a single ROI. When the CP was a single ROI, almost a half of fibres (147.6; SD ± 64.0) and half of the CST volume (26664U; SD ± 10059U) was obtained (all p < 0.05). There were no differences between the various CSTs in terms of fractional anisotropy, mean diffusivity, the apparent diffusion coefficient, radial diffusivity and the tract length (p > 0.05). The CST was infiltrated by a growing tumour or oedema in 17 of 32 patients; in these cases, the mean and apparent diffusion of the infiltrated CST was significantly higher than in uncompromised CSTs (p = 0.04). CST infiltration did not alter the other analysed parameters (all p > 0.05). CONCLUSIONS: A universal method of DTI of the CST was not developed. However, we found that the CP or the PLIC (with or without FL as the second ROI) should be used to outline the CST.

Readability of online patient education material for the novel coronavirus disease (COVID-19): a cross-sectional health literacy study.

OBJECTIVES: The internet has become one of the most important resources for the general population when searching for healthcare information. However, the information available is not always suitable for all readers because of its difficult readability. We sought to assess the readability of online information regarding the novel coronavirus disease (COVID-19) and establish whether they follow the patient educational information reading level recommendations. STUDY DESIGN: This is a cross-sectional study. METHODS: We searched five key terms on Google and the first 30 results from each of the searches were considered for analysis. Five validated readability tests were utilized to establish the reading level for each article. RESULTS: Of the 150 gathered articles, 61 met the inclusion criteria and were evaluated. None (0%) of the articles met the recommended 5th to 6th grade reading level (of an 11-12-year-old). The mean readability scores were Flesch Reading Ease 44.14, Flesch-Kincaid Grade Level 12.04, Gunning-Fog Index 14.27, Simple Measure of Gobbledygook SMOG Index 10.71, and Coleman-Liau Index 12.69. CONCLUSIONS: Online educational articles on COVID-19 provide information too difficult to read for the general population. The readability of articles regarding COVID-19 and other diseases needs to improve so that the general population may understand health information better and may respond adequately to protect themselves and limit the spread of infection.

Dural adhesion as a cause of late clip slippage from the medial cerebral artery aneurysm.

BACKGROUND: A properly placed clip may slip off the aneurysm during the postoperative period. Many factors have been attributed to this complication, although clip adherence to the dural stitch has not been reported. MATERIALS AND METHODS: Following the single occurrence of such unusual complication, 64 similar medial cerebral artery (MCA) aneurysms were retrospectively investigated at a single institution. Clip adherence to the dura demonstrated in early postoperative computed tomography (CT) was a presumed factor of a late clip migration in this study. RESULTS: In the series, there were 4 (6.3%) aneurysm remnants and 1 slipped clip that firmly adhered to the dura. In this particular case, the revision surgery revealed the spring coil firmly adhering to the dura in the previous suture line. Neither the occurrence of an aneurysm neck remnant nor clip slippage were related to the clip's adherence to the dura in the analysis of the entire group (p > 0.05). On the contrary, application of a fenestrated clip did contribute to that finding in multivariate analysis (p < 0.01). Unlike the rest, two surgeons unintentionally tended to position the clip close to the dura (p < 0.01). The clip-to-dura distance measured in the follow-up CT angiography 1 year after the surgery differed from that in the postoperative CT in 83.8% of the cases and decreased by an average of 0.5 mm. CONCLUSIONS: Clip-to-dura adherence should be regarded as a normal finding in the postoperative CT following MCA aneurysm clipping. Surgeons should consider the possibility of clip head protrusion into the dural stitch line.

Frontal aslant tract projections to the inferior frontal gyrus.

BACKGROUND: Frontal aslant tract (FAT) is a white matter bundle connecting the pre-supplementary motor area (pre-SMA) and the supplementary motor area (SMA) with the inferior frontal gyrus (IFG). The purpose of the present study was to evaluate the anatomical variability of FAT. MATERIALS AND METHODS: Total number of fibres and the lateralisation index (LI) were calculated. We attempted to find factors contributing to the diversity of FAT regarding IFG terminations to the pars opercularis (IFG-Op) and to the pars triangularis (IFG-Tr). Magnetic resonance imaging of adult patients with diffusion tensor imaging (DTI) with total number of 98 hemispheres composed a cohort. V-shaped operculum was the most common (60.5%). RESULTS: Total number of FAT fibres had widespread and unimodal distribution (6 to 1765; median: 160). Left lateralisation was noted in 64.3% of cases and was positively correlated with total number of FAT fibres and the bundle projecting to IFG-Op (p < 0.01). LI correlated with total number of FAT fibres (r = 0.43, p < 0.01). FAT projected predominantly to IFG-Op (88.9%; 88 of 99). Only in 3 (3.1%) cases more fibres terminated in IFG-Tr than in IFG-Op. Total number of FAT fibres and number of fibres terminating at IFG-Op did not correlate with the ratio of fibre numbers: FAT/IFG-Op, FAT/IFG-Tr and IFG-Op/IFG-Tr (p > 0.05). The greater total number of fibres to IFG-Tr was, the higher were the ratios of IFG-Tr/ /FAT (r = 0.57, p < 0.01) and IFG-Tr/IFG-Op (r = 0.32, p = 0.04). CONCLUSIONS: Among the IFG, the major termination of FAT is IFG-Op. Whereas the IFG-Tr projection seems to be related to the expansion of the entire FAT bundle regardless of side, domination and handedness. Nevertheless, FAT features a significant anatomical variability which cannot be explained in terms of DTI findings.

Intracranial region of the vertebral artery: morphometric study in the context of clinical usefulness.

BACKGROUND: The aim of this study was to analyse the morphometry of the intracranial segment of the vertebral artery in the context of clinical usefulness. The results were compared with published data available in full-text archived medical journals. MATERIALS AND METHODS: More than 100 digital subtraction angiography (DSA) and 3-dimensional (3D) angio-computed tomography (CT) examinations were used to measure the following parameters: the whole and partial length of V4 in characteristic anatomical points, the diameter in three places (on the level of foramen magnum, in point of exit to the posterior inferior cerebellar artery, and in the vertebro-basilar junction), the angle of connection to the vertebral arteries, and all anatomical variations including fenestration, duplication, dolichoectasia or absent artery. RESULTS: The left V4 section was predominant over the right artery, which is manifested by length, width, cases of ectasia and fewer cases of hypoplasia. The incidences of V4 ectasia were identified more often than those documented in the accessible literature, and they were found in the natural location of formation of saccular aneurysms. CONCLUSIONS: The presented knowledge of anatomical variation and abnormali-ties of vertebral circulation can improve the accuracy and "safety" of the surgical procedures in this region, help to determine the range of surgical approach and avoid associated complications. The radiological examinations using 3D CT, DSA reveal unlimited observation of anatomical structures in contrast to studies based on cadavers, and can complement the morphometry in anatomical preparations.

Future of the nerve fibres imaging: tractography application and development directions.

Tractography is a tool available in a growing number of centres, to enable planning of neurosurgical interventions. This method has some drawbacks and due to its increasing availability is causing a growing controversy over the possibility of an anatomical mapping of the nerve fibres. This article aims at summarising the application of the diffusion magnetic resonance in contemporary neurosurgery method, showing the usefulness and merits of its performance before surgical procedures, limitation of its application and recommendations for its improvement and more effective use for diagnostic purposes.

The posterior communicating artery: morphometric study in 3D angio-computed tomography reconstruction. The proof of the mathematical definition of the hypoplasia.

BACKGROUND: The aim of this study was to investigate the morphometry of the posterior communicating artery (PCoA), on the basis of angio-computed tomography (CT), and to give proof of the mathematical definition of the term "hypopal sia of the PCoA". MATERIALS AND METHODS: One hundred 3-dimensional (3D) angio-CT images, performed in adult patients with bilateral reconstruction of the PCoA (200 results) were used tocalculate the morphometry of the vessel. RESULTS: The average length of the vessel on the right side was 14.48 ± 3.47 mm, andon the left side 14.98 ± 4.77 mm (in women 14.75 mm, in men 14.70 mm). The mean of the diameter at the "proximal" point (the junction with P1) on the right side was 1.49 ± 0.51 mm, and on the left 1.46 ± 0.47 mm (in women 1.44 mm and in men 1.51 mm). The mean of the diameter in the "distal" part (the connection with ICA) on the right side was 1.4 ± 0.49 mm, and on the left 1.37 ± 0.41 mm (in women 1.38 mm, and in men 1.39 mm). No statistical correlation between the length and the diameter of the PCoA in relation to the sex and side was shown. On the basis of our measurements, we defined the hypoplasia of the artery as the estimated value less than the average diameter minus the standard deviation. The percentage distribution was as follows: the left artery 15.5%, the right artery 24%, women 11.5%, and the men 9%. Similarly to the above parameters, we have not found any statistical differences. The presence of the foetal origin was noted in 25% of the radiological examinations. The infundibular widening was visualised in 11.5% of cases of 3D reconstructions. The agenesis of PCoA was found in 9% (never bilaterally), and in 1 case the unilateral duplication of the artery was observed. No statistical differences between those parameters in relation to sex and the examined side were revealed. CONCLUSIONS: Morphological calculation of the PCoA on the basis of angio-CT from adult patients did not show any statistical differences depending on sex or the investigated side. The presented method of the calculations proved to be useful for the mathematical definition of the term "hypoplasia of the PCoA".

Quantification of white matter fibre pathways disruption in frontal transcortical approach to the lateral ventricle or the interventricular foramen in diffusion tensor tractography.

Pathologies occupying the interventricular foramen (foramen of Monro - FM) or the anterior part of lateral ventricle (LV) are accessed by the transcortical or transcallosal route. As severing of rostral corpus callosum has been deemed inferior to cortical incision, the approaches through various points of frontal lobe have been developed. Superior (F1), middle (F2) frontal gyrus or occasionally superior frontal sulcus are used as an entry of neurosurgical corridor. In spite of the fact that every approach to LV or FM causes its characteristic irreversible damage to white matter, to date all of transcortical routes are regarded as equivalent. The current study compared the damage of main neural bundles between virtualtrans-F1 and trans-F2 corridors by means of diffusion tensor tractography method (DTT) in 11 magnetic resonance imaging (MRI) exams from clinical series (22 hemispheres, regardless of dominance). Corpus callosum, cingulum, subdivisions I and II of superior longitudinal fasciculus (SLF I and SLF II), corticoreticular as well as pyramidal tracts crossing both approaches were subjected to surgical violation. Both approaches served a similar total number of fibres (0.94 to 1.78 [× 103]).Trans-F1 route caused significantly greater damage of total white matter volume(F1: 8.26 vs. F2: 7.16 mL), percentage of SLF I fibres (F1: 78.6% vs. F2: 28.6%)and cingulum (F1: 49.4% vs. F2: 10.6%), whereas trans-F2 route interrupted morecorticoreticular fibres (F1: 4.5% vs. F2: 30.7%). Pyramidal tract (F1: 0.6% vs. F2:1.3%) and SLF II (F1: 15.9% vs. F2: 26.2%) were marginally more vulnerable incase of the access via middle frontal gyrus. Both approaches destroyed 7% of callosal fibres. Summarising the above DTT findings, trans-F2 route disrupted a greater number of fibres from eloquent neural bundles (SLF II, pyramidal and corticoreticular tracts), therefore is regarded as inferior to trans-F1 one. Due to lack of up-to-date guidelines with recommendations of the approaches to LV or FM, an individual preoperative planning based on DTT should precede a surgery.

Trigeminal neuralgia caused by aneurysm of the posterior cerebral artery: a case description and the analysis of anatomical variety of vascular complex in the root entry zone of trigeminal nerve.

Trigeminal neuralgia is still a riddle, especially in the pathophysiology of the ticdouloureux, although the problem has been described in many medical publications. The major theory of pain based on the compression of the Vth nerve by tumours or vessels in the root entry zone (REZ) does not explain the facial pain in patient without neurovascular conflict, with multiple sclerosis or with conflict in places other than REZ. We report a case of the posterior cerebral artery aneurysm, which caused the isolated trigeminal neuralgia in a 48-year-old woman. She was operated on through microvascular decompression and the aneurysm was wrapped. In the second part of this study we review morphological variations of the neurovascular conflict on the basis of anatomical publications.

The pneumatisation of anterior clinoid process is not associated with any predictors that might be recognised preoperatively.

The anterior clinoid process (ACP) is usually removed during surgeries of proximal internal carotid artery (ICA) aneurysms. However, some ACPs present with air cells originating from the sphenoid or/and ethmoid sinus. In surgeries containing a clinoidectomy of a pneumatised process, up to 40% of patients experience cerebrospinal fluid (CSF) rhinorrhoea. The aim of this study was to explore the potential predictors of pneumatisation of the ACP, as well as to compare the occurrence of CSF rhinorrhoea between total and partial anterior clinoidectomies. This study comprised 2 different groups, with 2 different analyses. Firstly, the pneumatisation of the ACP was evaluated in 496 ACPs and was based on 248 computer tomography exams (CT). The c2 test and ROC curve comparisons were utilised in conjunction, to explore possible predictors of air cell accumulation in the ACP. The overall pneumatisation rate was 9.7%, unilateral and bilateral aerial ACP was found in 4.4% and 2.6% of all patients respectively, while at least one pneumatised ACP was found in 14.1% of examined patients. The route of pneumatisation was established in 87.5% of cases. The side of the ACP, gender, and patient age were not significantly associated with both pneumatisation of ACP or route of pneumatisation.Secondly, a clinical group of 23 patients after operative securing of an ICA aneurysm were retrospectively assessed with regards to the extent of anterior clinoidectomy and the occurrence of CSF rhinorrhoea. A total of 23 ACPs were removed, 17 ACPs were totally resected, and 6 underwent partial resection. CSF rhinorrhoea was not noted in any patients, thus the comparison between clinical groups was not valid. Moreover, we described a novel method of partial removal of the lateral aspect of ACP, which was applied in 6 patients treated for an ICA - ophthalmic artery junction aneurysm.

Morphometry of the pterional and pterional-orbitozygomatic approaches to the basilar artery bifurcation by the use of neuronavigation systems: a new technical concept.

Much attention has been paid in the neurosurgical literature to optimising the approaches to intracranial pathology. The aims of the innovations reported are to increase the safety of operations by reduction of brain retraction and to improve exposure of the neurovascular structure in the operating area. It was our intention to investigate whether an image-guided frameless stereotactic system is suitable in morphometric studies based on the analysis of the pterional and the cranio-orbitozygomatic approaches to the basilar artery bifurcation (BAB). We analysed 60 virtual models of pterional craniotomy and the same number of those extended by orbitozygomatic osteotomy, created using computer tomography in the neuronavigation system. It was decided to calculate the percentage change of the cranial area of exposure, the depth of the surgical corridor and the angle of view to the bifurcation of the basilar artery. Three positions of the BAB (normal, high and low) were examined for each model of craniotomy. In the material analysed, after the extension of the pterional craniotomy by orbitozygomatic osteotomy, the cranial area of exposure for 60 models of cranio-orbitozygomatic craniotomies increased by a mean of 39.28% (from 30.89% to 48.06%). The decrease in the depth of the surgical corridor for a normal-lying BAB was 19.16%, for a high-lying BAB 19.09% and for a low-lying BAB 19.12%. The mean changes in the individual BAB locations did not differ significantly in statistical terms (F = 0.011; p = 0.99). The mean increase in the cranial angle of attack for a normally located BAB was 10.72 degrees , for a high-lying BAB 11.1 degrees and for a low-lying BAB 10.31 degrees . The post-hoc test showed significant differences in the angle of attack between a normal and a low-lying BAB (p = 0.034) and a high and a low-lying BAB (p = 0.00007). Neuronavigation systems, already well-known for their intraoperative use, can also be useful in morphometric studies, and the advantages of this method are the practically unlimited number of results which can be analysed in detail and the repeatability of the technique. The pterional-orbitozygomatic approach compared to the pterional increases the working area, minimises retraction of the brain, shortens the working distance, enables instruments to be used more easily, widens the angle of view and improves the visibility of the anatomical structures in the working area, especially for a high-lying BAB.

Aneurysm of the meningeal branch of the occipital artery connecting with the distal portion of the posteroinferior cerebellar artery by the dural fistula.

We describe a case involving a ruptured intradural aneurysm of the meningeal branch of the occipital artery arising from the external carotid artery and connecting with the caudal loop of the posteroinferior cerebellar artery (PICA) by the dural fistula. Angiography of the left external carotid artery showed a saccular aneurysm of the occipital artery, but the picture of the left vertebral artery was normal and no vascular pathology such as an aneurysm or a dural fistula was noticeable between the meningeal branch of the occipital artery and the PICA. The diagnosis was confirmed by three-dimensional reconstruction computed tomography (CT) angiography, magnetic resonance imaging and magnetic resonance angiography (MRA). In the knowledge, based on the radiological examinations, that the aneurysm was located intracranially below the tonsil, compressing the lateral surface of the medulla oblongata at the level of the foramen magnum, we decided to operate from the far-lateral suboccipital approach, without removing the arc of the C1. An aneurysm was visualised at the site of the connection of the caudal loop of the PICA and an anastomosis of the meningeal branch of the occipital artery. The aneurysm was successfully clipped and the vascular fistula was coagulated and dissected in the extradural section. To our knowledge, the case presented here is the first report of this kind of vascular pathology. Careful analysis of a cross-sectional CT angiogram, MRA and arteriography is necessary for the proper diagnosis of such atypical vascular pathology. In the study presented we focus our attention on the diversity of the PICA anatomy.

[Vasospasm. Part II -- Onset time, localization, etiology. Proposed management algorithm in vasospasm]. / Skurcz naczyniowy, cz. II--Czas wystepowania, lokalizacja i etiologia. Propozycja algorytmu postepowania w stwierdzonym skurczu.

Time course of vasospasm in man has a big impact on clinical pisture, it also has an influence on the decision of surgery. The presence of acute stage of vasospasm is still under discussion. Many authors deny its existence. It is well known that positive decision about early operating has a crucial role in case of vasospasm Another problem is the aetiology of vasospasm. Inspite of many clinical and experimental investigations the aetiology of vasospasm remains unclear. The main problem is still the adequate therapy. This paper contains the updated knowledge about vasospasm, with the main accent on aetiology diagnosis and therapy.

[Vasospasm, part I: clinical symptomatology and differential diagnosis]. / Skurcz naczyniowy, cz. I--objawy kliniczne i róznicowanie.

Vasospasm is the most dangerous and common complication of subarachnoid haemorrhage (SAH) from ruptured brain aneurysms. The frequency of vasospasm is between 11 to 72% of SAH cases. One of the consequences of vasospasm is delayed neurological deficit (DND). Clinical diagnosis of vasospasm can course many diagnostic and therapeutic problems. This paper reviews the current developments concerning history, clinical picture and differential diagnosis of vasospasm.

[A case of radionecrosis of the pituitary gland region mimicking brain tumor. Case report]. / Przypadek martwicy popromiennej okolicy przysadki imitujacej proces rozrostowy. Opis przypadku.

A case is presented of delayed radiation necrosis of the pituitary gland region which appeared 2 years after tonsillar carcinoma surgery, followed by radiotherapy, in a 62-year old woman. Magnetic resonance imaging suggested the presence of an adenoma, metastases or craniopharyngioma, of the pituitary gland region. The lesion was resected, totally, using the fronto-orbital approach. Histopathological examination showed radionecrosis of the neurohypophysis. The patient was released from the hospital in a good health condition without neurologic deficits. On the basis of our case and reports of other authors, we can conclude that complications may arise as a result of radiation damage to neighbouring structures and there is also potential to induce malignant disease.

Virtual modelling of the surgical anatomy of the petrous bone.

The surgical anatomy of the petrous bone is difficult to learn and to imagine due to the porous structure. Obviously the surgeon's training is based on cadaver dissections as we are still lacking good, versatile models of the temporal bone and its important structures. The clearly visible, rapid development of computer science provides us with new possibilities that should be immediately engaged in modelling and simulating the human anatomy. The virtual, three-dimensional computer model of the bony pyramid was created based on the tomographic x-ray 1 mm slices and evaluated in accordance to its usefulness in learning and planning the neurosurgical approaches to the petrous region. The model was created in the virtual reality markup language, in order to make it available through the Internet. The basic anatomy of the main surgical approaches used in this region was visualised and evaluated in accordance with the real, intraoperative anatomy. The model could be easily accessed through the Internet. It was user-friendly and intuitive. The model seemed to be helpful in planning the basic approaches to the petroclival region. Computer science, with the help of the virtual modelling techniques, gives us a powerful method of learning and training surgical anatomy and approaches, although cadaveric dissection still remains the main point of the surgeon's training.

[Intracranial dissemination as the first important clinical sign of thoracic cord ependymoma in a boy aged 8]. / Rozsiew sródczaszkowy pierwszym, znamiennym objawem klinicznym wysciólczaka odcinka piersiowego rdzenia kregowego u 8 letniego chlopca.

This paper reports a case of the rare entity of a cerebral metastasizing ependymoma of the thoracic spinal cord in a 8 year old boy.

Surgical anatomy of anterior petrosectomy.

Neurosurgical procedures in the region of the petroclival region of the skull base require unique knowledge of the local anatomy. The measurements of this region considering the visible anatomical landmarks are helpful both during surgery and while planning the general schemes for the approach. We have evaluated the anatomy of the anterior surface of the petrous bone and of the middle fossa taking into consideration the surgical removal of part of the petrous bone--the anterior petrosectomy. We have measured the distances and angles between the chosen structures in this region. The measurements were taken on 10 skulls, on both sides. The results enrich the algorithm of the anterior petrosectomy.

[Granular cell tumor in the region of the hypophysis. Case report]. / Guz ziarnistokomórkowy okolicy przysadki. Opis przypadku.

We present a case of a 60-year old woman with a history of stroke with suspected aneurysm of anterior communicating artery. Angiography of cerebral arteries excluded the presence of an aneurysm. Magnetic resonance imaging showed the presence of a tumour in the area of the sella turcica. The tumour was resected, totally, using fronto-orbital approach. Histopathological examination showed granular cell type. The patient was released from the hospital in good health without any neurological deficits and hormonal disorders. On the basis of our case and reports of other authors we can conclude that benign character, usually with well defined boundaries from surrounding tissue and poorly vascularised, makes it easy to remove and gives good surgical results for this type of tumours.