Possible predictive clinical and radiological markers in decision making for surgical intervention in patients with Chiari Malformation type 1.

BACKGROUND: The first aim of this study was to compare the clinical data and posterior fossa morphometry obtained during the admission to the hospital between control group individuals (who had not Chiari Malformation (CM) type 1) and CM type 1 patients treated surgically or not. The second aim was to create a valid and reliable scale that can predict the decision-making for surgical intervention simply and easily in these patients. MATERIALS: Medical data and radiological images of 70 CM type 1 patients during their admission to the hospital were compared with the data of 69 control group individuals. RESULTS: Conservative treatment and/or follow-up was applied to 58 (82.9%) patients, and 12 (17.1%) patients underwent surgery. ROC analysis showed that the presence of myelopathy, tonsillar herniation >8 mm, Chamberlain line >84 mm, McRae line >44.50 mm, and odontoid process-McRae line angle <10.50 degrees could be used as predictive markers in decision-making for surgical intervention (p < 0.05). Logistic Regression analysis revealed that symptoms severity, and McRae line value would be the 'best parameters' in decision-making for surgical intervention (p < 0.05). A scale named the CHIASURG scale developed using this study's parameters showed that the parameters of 'depth of tonsillar herniation', 'Chamberlain line', and 'McRae line' could predict the surgical intervention risk. CONCLUSION: It was found that symptoms severity and McRae line value could be used as predictive markers in decision-making for surgical intervention. Additionally, it was concluded that a new scale called CHIASURG could predict surgical intervention risk validly and reliably.

Noticable Findings in Cranial MRI of the Patients with Idiopathic Intracranial Hypertension.

OBJECTIVES: Idiopathic intracranial hypertension (IIH) is characterized by increased intracranial pressure. We investigated the optic nerve, Meckel's cavity, internal carotid artery (ICA) and pituitary findings of IIH by Cranial Magnetic Resonance Imaging (MRI). METHODS: Cranial MRI images of 35 adult patients with IIH and 35 adult subjects with normal cranial MRI results (control) were evaluated. Optic nerve diameter (OND), optic nerve sheat diameter (ONSD), OND/ONSD ratio, ON tortuosity, ON protrusion, posterior scleral flattening, ICA transverse diameter, CSF distance in Meckel's cavity and ICA transverse diameter/CSF distance in Meckel's cavity ratio, and pituitary gland measurements (height and transverse dimension; and Optic chiasm- pituitary gland distance) were measured. RESULTS: OND and ONSD of the IIH group were significantly higher than those of the control groups at anterior and posterior measurements (p < 0.05). OND/ONSD ratio of the IIH group was lower at anterior measurement; and higher at the posterior measurement than the control group (p < 0.05). Right ICA transverse diameter and bilateral CSF distance in Meckel's cavity of the IIH group were higher than those of the control. Optic chiasm- pituitary gland distance of the IIH group was significantly higher than that of the control group (p < 0.05). CONCLUSION: OND/ONSD ratio is different in anterior and posterior measurements. So we recommend measuring OND and ONSD separately in IIH patients to use in the clinical practice. Similarly, optic chiasm-pituitary gland distance is also another point to note for IIH patients on MRI. Our paper adds new approach to IIH in terms of OND/ONSD ratio.

Peripheral and central smell regions in COVID-19 positive patients: an MRI evaluation.

BACKGROUND: Coronaviruses may lead to invasion of the central nervous system. PURPOSE: To investigate the effects of COVID-19 infection on smell using cranial magnetic resonance imaging (MRI). MATERIAL AND METHODS: Cranial MRI scans of 23 patients with COVID-19 (patient group [PG]) and 23 healthy controls (HCs) were evaluated. Peripheric (olfactory bulb [OB] volume and olfactory sulcus [OS] depth) and central (insular gyrus and corpus amygdala areas) smell regions were measured. RESULTS: Smell loss was present in nine patients (39.1%) in the PG. The means of the disease duration and antiviral treatment were 3.00 ± 2.35 and 5.65 ± 1.72 days, respectively. OB volumes of the PG were significantly lower than those of the HCs bilaterally. However, no significant differences were observed between the OS depth, insular gyrus, and corpus amygdala areas of both groups. The left corpus amygdala areas were both increased with the increased disease (P = 0.035, r = 0.442) and treatment durations (P = 0.037, r = 0.438). In the PG, longer treatment duration, increase in C-reactive protein (CRP), lymphocyte count decrease, and positive thoracic computed tomography (CT) involvement were related to OS depth decrease. Right corpus amygdala areas increased in patients with COVID-19 with increased D-dimer values, and thoracic CT involvement was detected. CONCLUSION: COVID-19 disease affects the peripheric smell region of OBs and does not affect the central smell regions of the insular gyrus and corpus amygdala areas. The importance of our study is to detect MRI findings in patients with COVID-19 leading to odor disorders. These findings may help in diagnosing the disease at an early stage.

Important landmarks and distances for posterior fossa surgery measured by temporal MDCT.

In this retrospective study, we aimed to present important anatomical structures and distances for posterior fossa surgery by temporal multidetector computed tomography (MDCT). The temporal MDCT images of 317 adult patients (158 males and 159 females) were retrieved from the hospital's picture archiving and communication system (PACS). In the coronal temporal MDCT views, the cochlea-carotid canal and jugular bulb-mastoid bone outer surface were measured. In the axial MDCT views, the carotid canal-jugular bulb and carotid canal-posterior fossa distances were measured; the carotid canal and jugular bulb anterior-posterior (AP) and transverse dimensions were also measured. The bilateral cochlea-carotid canal, jugular bulb-mastoid bone outer surface, and right carotid canal-jugular bulb distances were significantly greater in the males than those in the females (p < 0.05). The carotid canal-posterior fossa distance was not different in both genders (p > 0.05). The carotid canal-jugular bulb and the carotid canal-posterior fossa distances were greater on the left side than those on the right side in both genders (p < 0.05). In males, the outer surface distance was greater on the left jugular bulb-mastoid bone than that on the right side of that bone (p < 0.05). The difference between the carotid canal AP dimensions was not significant between males and females (p > 0.05). However, the carotid canal transverse dimension, jugular bulb AP, and transverse dimensions were significantly greater in the males than those in the females, bilaterally (p < 0.05). In each gender separately, the carotid canal AP and transverse dimensions were greater on the left side and the jugular bulb AP and transverse dimensions were greater on the right side than those on the left side (p < 0.05). Positive correlations were found between the cochlea-carotid canal, the jugular bulb-mastoid bone outer surface, and the carotid canal-jugular bulb distances as well as between the jugular bulb-mastoid bone outer surface and the carotid canal-posterior fossa distances (p < 0.05). In older patients, the carotid canal-posterior fossa distances were shorter on the left side (p < 0.05). Vascular and neural localizations should be well understood in the operative area before applying the surgical approach in the posterior fossa. Computed tomography (CT) has a greater role in the evaluation of bone structures and vascular canals in this area.

Strain and Shear Wave Elastography in Diagnosis of Retrobulbar Neuritis.

BACKGROUND: In the early stages of retrobulbar neuritis (RN), the optic disc appears normal on ophthalmoscopy. Therefore, the diagnosis of RN is usually made clinically. However, imaging tools are needed for precise diagnosis of RN, and usually MRI is used. In this study, we investigated the diagnostic performance of strain elastography (SE) and shear wave elastography (SWE) in patients with RN. Elastography is a new sonographic technique and a noninvasive ultrasound method for evaluating the elastic properties of tissues based on static compression: the elastographic techniques of SE compress the tissues axially, and SWE uses waves that are generated by transducers and interact with the tissue. METHODS: The study included 40 eyes of 20 patients with sudden visual loss, who were diagnosed with RN. The eyes of the patients were divided into 2 groups: the eye with a diagnosis of RN was the group of RN eyes, and the healthy second eye was the group of control eyes. Ophthalmologic examination, orbital and brain MRI, SE, and SWE were performed. SE color mapping was divided into 3 types: blue-hardest tissue (Type 1), blue/green-hard tissue (Type 2), and green-intermediate tissue (Type 3). All patients were treated with high-dose corticosteroids. The measurements of SE and SWE were made immediately after diagnosis and 1 month after treatment. RESULTS: The mean age of 11 male and 9 female patients was 38.3 ± 12.2 years. At the time of diagnosis, the mean shear wave values for the control eyes were 18.47 ± 7.26 kPa (kilopascals), and the mean shear wave values for the RN eyes were 37.21 ± 8.24 kPa. There was a statistically significant difference between the control and RN eyes at the time of diagnosis (P < 0.001). The mean shear wave value was 19.92 ± 4.77 kPa in the RN eyes after treatment. There was a statistically significant difference in values at the time of diagnosis and after treatment (P < 0.001). Strain types found in the RN eyes before treatment were Type 1 in 60% of eyes, Type 2 in 25%, and Type 3 in 15%; at the end of the treatment, Type 2 was observed in 25% of eyes and Type 3 in 75%, while Type 1 was not observed. CONCLUSIONS: SE and SWE may be important alternative diagnostic tools in the diagnosis of RN.

Is there a relationship between basilar artery tortuosity and vertigo?

OBJECTIVE: The aim of this study was to investigate the relationship between basilar artery (BA) tortuosity, hypogenesis/agenesis of the vertebral artery (VA), and vertigo, with the use of magnetic resonance imaging (MRI). PATIENTS AND METHODS: This case-control study included patients admitted to the outpatient clinics, who were aged 18-80 years, without any known systemic diseases. All patients were evaluated with a 1.5-tesla MRI system. BA Tortuosity, VA agenesis, and VA asymmetry were noted. BA diameter (central) and length (longitudinal) were measured. RESULTS: A total of 154 vertigo patients (46 M, 108 F; mean age of 48.95 ± 17.3 years) and 346 control subjects (112 M, 234 F; mean age of 45.12 ± 17.0 years) were included. The mean age of the vertigo patients was significantly higher than that of the control group (48.95 vs 45.12 years) (p = 0.021). The rate of BA tortuosity was higher in patients with vertigo (p = 0.030). When the participants were divided into two groups according to median age (<45 vs. ≥45 years) there was no statistically significant difference between the groups in terms of VA asymmetry (p = 0.070) and hypogenesis/agenesis (p = 0.577). There was a statistically significant difference between the groups in respect of BA tortuosity (p = 0.033), BA diameter (p < 0.001), and BA length (p < 0.001). When the study populations were divided into two groups according to the presence of vascular tortuosity, the mean age, BA diameter, and BA length values were higher in the tortuosity (+) group (all p < 0.001). CONCLUSION: These results demonstrated that vertigo and BA tortuosity rates seem to increase with age. Likewise, BA diameter and length increased with age, although there was no significant relationship with vertigo. Patients with tortuosity were significantly older, and had higher rates of VA asymmetry/agenesis, and increased BA diameter compared to subjects without tortuosity.

Sonoelastographic evaluation of the sciatic nerve in patients with unilateral lumbar disc herniation.

OBJECTIVE: The aim of this study was to compare strain elastography (SE) and shear wave elastography (SWE) findings of the sciatic nerve in patients with unilateral lumbar disc herniation (LDH) and healthy control subjects. MATERIALS AND METHODS: The study group included patients with complaints of unilateral sciatica for 3-12 months, with foraminal stenosis due to one level of LDH (L4-L5 or L5-S1). An age- and gender-matched control group was formed of healthy subjects. Evaluations were performed on both the axial and longitudinal planes from the bilateral gluteal region using a 5-9 MHz multifrequency convex probe. RESULTS: There were 40 patients (20 male, 20 female) with a mean age of 43.1 ± 12.7 years in the study group, and 40 healthy subjects (22 male, 18 female) with a mean age of 42.9 ± 10.7 years in the control group (p > 0.05). The sciatic nerve stiffness assessed on both the axial (12.3 ± 3.7 kPA) and longitudinal (14.3 ± 3.8 kPA) planes of the involved side was significantly higher than non-involved side (axial: 6.8 ± 2.1 and longitudinal: 8.3 ± 2.3 kPA) in the patient group (p < 0.001). CONCLUSIONS: Patients with unilateral LDH have increased stiffness of the sciatic nerve compared to healthy control subjects. Although the findings in this preliminary study show that shear wave elastography can detect a change in sciatic nerve stiffness in patients with unilateral LDH, larger studies are required to determine the clinical utility of this technique.

Evaluation of tendinosis of the long head of the biceps tendon by strain and shear wave elastography.

AIM: To investigate strain (SE) and shear wave elastography (SWE) characteristics of the long head of the biceps tendon (LHBT) tendinosis in comparison with magnetic resonance imaging (MRI) findings. MATERIAL AND METHODS: Twenty patients with a MRI diagnosis of tendinosis and twenty healthy subjects with normal LHBT in MRI were prospectively examined by SE and SWE. SE color mapping was divided into four types in accordance with elasticity designs: type I predominantly blue (hardest tissue), type II predominantly blue-green (hard tissue), type III predominantly green (intermediate tissue), type IV predominantly green-yellow-red (soft tissue). Quantitative measurements of LHBT hardness with SWE were analyzed in kilopascals (kPa). RESULTS: In the tendinosis group SE types in transverse scan were I in 24% of tendons, II in 50%, III in 25%, and in longitudinal scan I in 15%, II in 75%, and III in 10%. In the control group SE types in transversescan were II in 10% of tendons, III in 55%, IV in 35%, and in longitudinal scan II in 10%, III in 55%, and IV in 35%. SWE values in transverse scan were 38.32±7.2 kPa in the tendinosis group and 18.6±3.1 kPa in the control groupand in longitudinal scan 39.42±7.4 kPa in the tendinosis group, and 20.62±4.6 in the control group. There was a statistically significant difference in terms of elasticity patterns between the tendinosis and control groups (p<0.001). The receiver operating characteristic curve analysis was perfect and a cut-off value of tranverse 25.8 kPa and longitudinal, 24.6 kPa shear values had very high sensitivity and specificity for tendinosis. CONCLUSION: SE and SWE may be useful diagnostic tools for LHBT tendinosis when considering usability, cost effectiveness, and patient preference compared to MRI.

Ultrasound Elastography of the Median Nerve in Patients With Acromegaly: A Case-Control Study.

OBJECTIVES: The aim of this study was to compare the cross-sectional area and ultrasound elastographic findings of the median nerve of patients with acromegaly and healthy participants. METHODS: The acromegaly group comprised 15 patients with a previous diagnosis of acromegaly, and an age- and sex-matched control group included healthy participants. Strain elastographic and shear wave elastographic findings and the cross-sectional areas of the groups were compared. A 6-15-MHz multifrequency transducer was used for ultrasound evaluations. RESULTS: A total of 30 hands of 15 patients with acromegaly (7 male and 8 female) with a mean age ± SD of 50.00 ± 10.17 years and 40 hands of 20 healthy control participants (9 male and 11 female) with a mean age of 49.50 ± 10.17 years were taken into consideration for statistical analyses. The cross-sectional area of the patients with acromegaly was significantly higher than that of the healthy controls (13.43 ± 3.12 versus 8.32 ± 1.94 mm2 ; P < .05). Median nerve stiffness was significantly increased in the acromegaly group compared with the control group (axial and longitudinal, 37.15 ± 6.4 and 37.0 ± 6.19 versus 18.7 ± 4.1 and 19.2 ± 3.58 kPa, respectively; P < .001). CONCLUSIONS: These preliminary results have demonstrated that patients with acromegaly seem to have increased stiffness and cross-sectional area of the median nerve compared with healthy participants.

Evaluation of Optic Nerve with Strain and Shear Wave Elastography in Patients with Behçet's Disease and Healthy Subjects.

The objective of this study was to investigate the elasticity characteristics of the optic nerve using strain and shear wave elastography in patients with Behçet's disease and to compare the results with those of healthy volunteers. Forty-six optic nerves from patients with Behçet's disease and 54 optic nerves from healthy volunteers were investigated prospectively in this study using strain and shear wave elastography. There was a statistically significant difference in terms of elasticity patterns between patients and healthy volunteers (p < 0.001). Elastographic images of healthy volunteers revealed most optic nerves to be type 3 (51.8%); however, type 2 (40.7%) and type 1 (7.5%) were also observed. Elastographic examination of Behçet's disease patients revealed type 2 in 52.2%, type 1 in 43.5% and type 3 in 4.3% of patients. Statistically significant differences were observed between patients and healthy volunteers in the analysis of shear wave elastography values (p < 0.001). Receiver operating characteristic curve analysis was perfect (0.933) (95% CI = 0.885-0.980), and a cutoff value of 16.5 kPa shear had very high sensitivity and specificity for the patient group. Strain and shear wave elastography findings for the optic nerves of patients with Behçet's disease were significantly different from those for healthy volunteers.

Can Achilles tendon be used as a new distal landmark for coronal tibial component alignment in total knee replacement surgery? An observational MRI study.

BACKGROUND: In total knee arthroplasty, it is better to use more than one reference point for correct alignment of the components. By measuring the distances of Achilles tendon (AT) and other conventional landmarks from the mechanical axis in magnetic resonance imaging (MRI) of the ankle, we aimed to demonstrate that, as a novel landmark which can help for correct alignment in the coronal plane, AT is a better option than other landmarks. MATERIALS AND METHODS: This retrospective study was done on 53 ankle MRIs that met the criteria for inclusion to the study among 158 ankle MRIs. After identification of the mechanical axis, the distances of distal landmarks, which were extensor hallucis longus tendon (EHLT), tibialis anterior tendon (TAT), dorsalis pedis artery (DPA), AT, extensor digitorum longus tendon (EDLT), and malleoli, were measured from the mechanical axis and were statistically evaluated. RESULTS: In proximal measurements, the distances of the landmarks to the mechanical axis (on average) were AT, 2.64±1.62 mm lateral; EHLT, 3.89±2.45 mm medial; DPA, 4.69±2.39 mm medial; TAT, 8.24±3.60 mm medial; and EDLT, 14.2±4.14 mm lateral (P<0.001). In distal measurements, the distances of the landmarks to the mechanical axis (on average) were AT, 1.99±1.24 mm medial; EHLT, 4.27±2.49 mm medial; DPA, 4.79±2.10 mm medial; TAT, 12.9±4.07 mm medial; and EDLT, 12.18±4.17 mm lateral (P<0.001). CONCLUSION: In this study, the mechanical axis line, which is the center of talus, passes through the AT. Our MRI investigations showed that the AT, EHLT, DPA, and malleolar center (3-5 mm medial) may help in correct alignment.

The importance of medial-lateral styloid process angulation/coronal plane angle in symptomatic eagle syndrome.

We used three-dimensional computerized tomography (3DCT) to obtain images of Eagle Syndrome (ES) cases and measurements of relevant variables. Twenty-five subjects with ES and 25 controls were included in this retrospective study. Styloid process length, anterior-posterior styloid process angulation (Sagittal plane angle) (APA), medial-lateral styloid process angulation (Coronal plane angle) (MLA), tonsil-stiloid distance and carotid-stiloid distance were measured on CT and 3DCT images, and cranial and neck angiography was obtained, from a total of 580 images. The styloid process lengths were 40.3 and 40.5 mm on the right and left sides in the ES group. The left MLA was lower in symptomatic (Median: 67.0°) than asymptomatic (Median: 72.6°) ES patients. In ES patients with styloid process length above 3 cm, MLA (coronal plane angle) is important, and the symptoms are more intense when this angle is smaller. Clin. Anat. 30:487-491, 2017. © 2017 Wiley Periodicals, Inc.

Evaluation of posterior clinoid process pneumatization by multidetector computed tomography.

In the present study, we investigated the types and ratio of posterior clinoid process (PCP) pneumatization in paranasal sinus multidetector computed tomography (MDCT). Paranasal MDCT images of 541 subjects (227 males, 314 females), between 15 and 65 years old, were included into the study. Pneumatization of anterior clinoid process and pneumatization types (I, II, or III) were evaluated in the males and females. PCP pneumatization was detected in 20.7 % of the males and 11.5 % of the females. Right, left, and bilateral PCP pneumatizations were detected in 7.9, 5.7, and 7.0 % of the males and 2.9, 3.2, and 4.5 % of the females, respectively. PCP pneumatization of the males is significantly higher than the females. The most detected type of pneumatization was type I (61.2 %) for all groups. In right, left, and bilateral pneumatizations separately, type I pneumatization was the most detected pneumatization type with the ratio of the 70.4, 65.2, and 50.0 %, respectively. In males, type I (61.7 %), and similarly in females, type I (60.6 %) pneumatization were detected more. Type II and type III pneumatizations were detected in decreasing order in both groups. In younger subjects, pneumatization of posterior clinoid process was found as higher, and in older subjects, PCP pneumatization was found as lower. Sclerosis process related to the aging may be responsible for the lower pneumatization ratios in older subjects. Structure of the surrounding regions of PCP is important for surgical procedures related to cavernous sinus, basilar apex aneurysms, and mass lesions. Preoperative radiological examinations are useful for operative planning. Any anomalies to PCP can cause unnecessary injury to the neurovascular complex structure around the cavernous sinus or postclinoidectomy CSF fistulas. Posterior clinoidectomies should be avoided in patients with type III PCP pneumatization to prevent CSF fistulas.

Changes of normal appearing optic nerve head on diffusion-weighted imaging in patients with diabetic retinopathy.

PURPOSE: To investigate whether there is any change by measuring ADC values particularly of the optic nerve head (ONH) in patients with diabetic retinopathy (DR). MATERIAL AND METHODS: ADC values at the ONHs was measured in 56 patients and 68 controls. RESULTS: ADC values of ONHs were significantly higher in patients with DR compared to controls (p=0.011). ADC values in patients with macular edema were higher than those without macular edema (p=0.017). CONCLUSION: DWI of ONHs can be useful in cases where it is difficult to assess macular edema during fundus examination, especially in diabetic patients with cataract.

Is strain elastography beneficial for isoechoic cholangiocarcinomas?

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Presence and types of anterior clinoid process pneumatization, evaluated by Multidetector Computerized Tomography.

PURPOSE: The types and ratio of anterior clinoid process (ACP) pneumatization in paranasal sinus Multidetector Computerized Tomography (MDCT) were investigated the importance of ACP in neurosurgical approaches discussed. METHODS: Paranasal MDCT images of 499 subjects (259 male, 240 female), between 17 and 65 years of age, were included in the study. Presence and types of pneumatization of the ACP and pneumatization types (I, II or III) were evaluated. RESULTS: ACP pneumatization was detected in 37.5% of the males and 33.3% of the females. Right, left and bilateral ACP pneumatizations were detected in 12.7%, 9.3% and 15.4% of males and 9.2%, 8.3% and 15.8% of the females, respectively. The most commonly detected types of pneumatization were Type I (49.1%) for right pneumatizations and Type II pneumatization for left (40.9%) and bilateral (37.2%) pneumatizations. In males, Type I (37.1%) and in females, Type II (40.0%) pneumatizations were detected more frequently. Type III pneumatization was detected in 29.9% of the males and 22.5% of the females. ACP pneumatization ratios were higher in younger subjects and lower in older subjects. CONCLUSION: Sclerosis process related to aging may be responsible for the lower pneumatization ratios in older subjects. When Type III ACP pneumatization is present, clinoidectomy should not be performed: in this type of ACP pneumatization, cerebrospinal fluid fistula develops in all cases.

Magnetic resonance imaging and computed tomography for diagnosing semicircular canal dehiscence.

OBJECTIVES: We investigated the semicircular canal (SC) dehiscence using temporal computed tomography (CT) and magnetic resonance (MR) imaging. METHODS: We retrospectively reviewed 114 (228 ears) consecutive MR images and CT scans of the temporal bones for dehiscence of the SCs. In the 1.5 Tesla (T) MR imaging, T1 and T2-weighted images were obtained. Dehiscence of the SCs was defined by absence of high attenuation bone coverage on the CT scans, and absence of low-signal bone margins on the MR images. RESULTS: Superior SC dehiscence was detected in 4 (1.8%) ears using CT scans and 5 (2.2%) ears using MR imaging. Posterior SC dehiscence was detected in 4 (1.8%) ears using CT scans and 4 (1.8%) ears using MR imaging. In the non-dehiscent cases, there was hypointense bone coverage between the canal and the cerebrospinal fluid (CSF). However, in the cases of semicircular canal dehiscence, hypointense bone tissue did not appear between the canal and the CSF in the MR imaging. CONCLUSION: If there is clinical doubt about the presence of SC dehiscence, we recommend that MR imaging be conducted first. When dehiscence is not seen in the MR, a CT examination should be performed. MR imaging is preferred primarily, because it does not contain ionizing radiation.

Is there a relationship between sphenoid sinus types, septation and symmetry; and septal deviation?

In the present study, we investigated whether there is a relationship between sphenoid sinus (SS) types, septation (lobulation) and symmetry; and septal deviation (SD) by multidetector computed tomography (MDCT). Paranasal MDCT images of 202 subjects (131 males, 71 females), between 10- and 88-year-old, were included into the study. SS type (conchal, presellar or sellar), SS symmetry, SS septation (lobulation) and SD were evaluated by MDCT images. In the present study, in both males (83.2 %) and females (85.9 %); and in all age groups (80.4-85.7 %), sellar type sphenoid sinus were more detected. Conchal type was detected in two cases of the males (1.5 %) and none of the females. SS was detected mainly as multi-septated (multi-lobulated) (51.9 % in males and 56.3 % in females; in all age groups as 51.0-56.8 %; and both SD (+) and SD (-) groups as 51.2-56.8 %). In subjects with SD, asymmetric SS was detected in 80.2 %. Whereas in SD (-) subjects, asymmetric SS was detected in 50.6 %. Sellar type SS pneumatization is the most detected type in our cases. Presence of SD was related to the higher SS asymmetry values. In SD (-) subjects, SS was detected as symmetric. Nasal septal deformities such as SD may influence the development of the SS pneumatization and asymmetric septation. For well anatomic orientation of the surgeons, good anatomy knowledge and preoperative detailed examination of the CT scans are very important.

Investigation of the calcification at the petroclival region through Multi-slice Computed Tomography of the skull base.

OBJECTIVES: The aim of this paper was a retrospective investigation of calcification at the petroclival region using Multi-slice Computed Tomography (MSCT). METHODS: One hundred thirty skull bases were reviewed. The images were acquired with a 64 slice CT (MSCT). At first images were taken at the axial plane; and then coronal and sagittal reconstructions of raw data were performed. Later investigations were carried out on these 3-dimensional images (3-D imaging). Petrosphenoidal ligament (PSL) (Gruber's ligament) and posterior petroclinoid ligament (PPCL) calcifications were evaluated as "none, partial or complete calcification" for the right and left sides. RESULTS: In the right PSL, there were partial calcifications in 9.8% and complete calcifications in 2.3%. Calcification ratio was 9.8% partial and 2.9% complete in the left PSL. In the right side, there were 26.6% partial and 5.2% complete calcifications of PPCL. In the left side, there were 29.5% partial and 4.6% complete PPCL calcifications. PPCL calcification was detected more in males compared to females in the right and left sides. In older patients, left PSL; right and left PPCL calcification were detected more. CONCLUSION: PPCL calcifications cannot be differentiated from PSL calcifications in MSCT slices. The distinction can be easily done in 3-D views. The presence of ossified ligaments may make surgeries in this region difficult, and special care has to be taken to avoid injuries to structures which pass under these ossified ligaments. Particularly in elderly patients, the appropriate surgical instrument for the PSL calcifications should be prepared preoperatively. If PSL is calcified, 6th cranial nerve palsy may not occur even though increased intracranial pressure syndrome is present. Whereas, in lateral trans-tentorial herniations, 3rd cranial nerve palsy occurs in earlier periods when PSL is calcified. Moreover, in subtemporal and transtentorial petrosal approaches, knowing the PSL calcification preoperatively is important to avoid damaging the 6th cranial nerve during surgery.

The Presence of Clival Foramen Through Multidetector Computed Tomography of the Skull Base.

OBJECTIVES: Technological advancements in the diagnostic radiology recently permitted reviewing the normal anatomy through multidetector computed tomography (MDCT) imagination. The aim of this paper is retrospectively investigation of the clival foramen and canal through MDCT. MATERIALS AND METHODS: One hundred eighty-six MDCT scans were reviewed. First, images were taken at axial plane, and then coronal and sagittal reconstructions of raw data were performed. Later investigations were carried out on these three-dimensional images (3-D imaging). The images were evaluated as clival foramen "present" or "absent." RESULTS: In our 186 patients, evaluation of MDCT showed that clival foramen was absent in 66.7% (n = 124) of patients. Only 33.3% (n = 62) of patients had a clival foramen. In 3-D images, clival canal and clival foramen were shown more clearly compared with the MDCT. CONCLUSIONS: Knowledge of the clival canal might be useful in patients of questionable clival fracture or during neurosurgical operations in this region. During life the canal contained a vein connecting the basilar plexus with the venous plexus of the vertebral canal, and inferior petrosal sinuses. Before the surgical interventions in the clival region, the presence of the clival canal and foramen should also be known due to its vascular contents. By multidetector computed tomography and 3-D images, clival canal and foramen may be viewed preoperatively.