Radiologic evaluation of the Vidian canal in the pediatric population.

PURPOSE: This examination aimed to display the size and topographic position of the Vidian canal (VC) in normal children. METHODS: 180 pediatric subjects aged 1-18 years were included this computed tomography examination. The distances of VC to certain landmarks, and VC length were measured. The locations of VC according to the sphenoid sinus, and the medial plate of pterygoid process were classified as three types, separately. RESULTS: The distances of VC to the vomerine crest, midsagittal plane, round foramen, and the superior wall of sphenoid sinus were measured as 12.68 ± 3.17 mm, 10.76 ± 2.52 mm, 8.62 ± 2.35 mm, and 14.16 ± 5.00 mm, respectively. The length and angle of VC were measured as 12.00 ± 2.52 mm, and 16.60 ± 9.76°, respectively. According to the sphenoid bone, VC location was identified as Type 1 in 113 sides (47.5%), as Type 2 in 70 sides (29.4%), and as Type 3 in 55 sides (23.1%). According to the medial plate of pterygoid process, VC location was identified as Type A in 274 sides (76.1%), as Type B in 55 sides (15.3%), and as Type C in 31 sides (8.6%). VC location types correlated with pediatric ages, but not sex or side. CONCLUSION: With advancing pediatric age, the protrusion of VC into the sphenoid sinus increases, and VC shifts from medial to lateral side of the medial plate of pterygoid process.

Topographic Anatomy and Pneumatization of the Posterior Clinoid Process in Chiari Type I Malformation.

OBJECTIVE: This study aimed to examine pneumatization and topographic location of the posterior clinoid process (PCP) in Chiari type I malformation (CIM) for skull base approaches. METHODS: Computed tomography images of 52 (23 males/29 females) CIM subjects aged 23.87 ± 16.09 years and 71 (26 males/45 females) healthy subjects aged 42.48 ± 21.48 years constituted the study universe. RESULTS: The distances of PCP to the foramen magnum (P = 0.037), superior orbital fissure (P < 0.001), foramen rotundum (P < 0.001), and foramen ovale (P < 0.001) were smaller, but the distance of PCP to the crista galli (P = 0.038) was greater in CIM patients, compared with normal subjects. In CIM, the fusion between PCP and the anterior clinoid process was observed in 9 sides (8.70%), while in controls it was observed in 12 sides (8.50%). PCP pneumatization was observed in 40 sides (38.50%) in CIM patients, while it was observed in 28 sides (19.70%) in normal subjects. These data displayed that PCP pneumatization was affected by CIM (P < 0.001). CONCLUSIONS: The distances of PCP to the crista galli and foramen magnum indicate the anterior fossa length and the posterior fossa depth, respectively; thus CIM patients have a longer anterior fossa and a shallow posterior fossa. In addition, the distances of PCP to the superior orbital fissure, foramen rotundum, and foramen ovale indicate the middle fossa width; hence CIM patients have less middle fossa width than normal individuals. CIM patients have an approximately 50% higher PCP pneumatization rate, and this may increase the risk of complications such as cerebrospinal fluid fistula during the application of posterior clinoidectomy.

Massa intermedia in adults: incidence, dimension, location and clinical importance.

PURPOSE: This retrospective magnetic resonance imaging investigation aimed to obtain information related to the anatomy of the massa intermedia (MI) in an adult population. METHODS: The work conducted on MRI views of 1058 (539 males and 519 females) healthy adult samples aged with 48.93 ± 17.63 years. Initially, the presence or absence of MI was noted, and then if present, its numbers and location in the third ventricle were recorded. Its horizontal (HDMI) and vertical (VDMI) diameters were measured on MRI views, while the cross-sectional area (CSAMI) was calculated using its diameters. RESULTS: MI was missing in 2.6% (27 cases) of 1058 adult samples. Six subjects (0.6%) had a double MI. HDMI, VDMI and CSAMI were measured as 4.83 ± 1.01 mm, 4.86 ± 0.98 mm, and 19.11 ± 7.23 mm2, respectively. MI size did not show a significant alteration from 19 up to 49 years, but then its size distinctly decreased between 50 and 60 years. After age 60, MI dimension did not display an important change. MI was settled in the antero-superior quadrant in 929 cases (90.63% of 1025 subjects), in the postero-superior quadrant in 22 cases (2.15%), in the antero-inferior quadrant in 32 cases (3.12%), in the postero-inferior quadrant in 8 cases (0.78%), and in the central part in 34 cases (3.32%). CONCLUSIONS: The size, position and incidence of MI were not affected by sex, and its position and incidence were not affected by adult age periods. In adults, MI size demonstrated a significant decrease in the middle age.

Anatomic Features of the Interthalamic Adhesion in the Pediatric Population.

OBJECTIVE: The main goal of this retrospective study was to examine the morphology of the interthalamic adhesion (ITA) in normal children aged between 1 and 18 years. METHODS: The study universe consisted of magnetic resonance images of 180 healthy pediatric subjects (age, 9.50 ± 5.20 years, sex, 90 girls and 90 boys). The cross-sectional area (CSA), vertical diameter (VD), and horizontal diameter (HD) of the ITA were measured and in addition, its location was noted. RESULTS: HD, VD, and CSA of the ITA were measured as 8.47 ± 1.64 mm, 7.59 ± 1.57 mm, and 52.06 ± 18.51 mm2, respectively. HD did not change from infancy until postpubescence, but then significantly decreased (P < 0.001). VD increased up to early childhood but then did not alter until the end of prepubescence. After that period, it decreased in postpubescence (P < 0.001). CSA tended to decrease in an irregular pattern according to pediatric age periods (P < 0.001). The ITA was located at the anterosuperior quadrant in 138 individuals (76.70%), at the anteroinferior quadrant in 7 individuals (3.90%), and the center of the lateral wall of the third ventricle in 35 individuals (19.40%). Linear functions were calculated as y = 9.490-0.107 × age (years) for HD, y = 8.453-0.091 × age (years) for VD, and y = 63.559-1.211 × age (years) for CSA. CONCLUSIONS: ITA size irregularly decreases with advancing age from 1 to 18 years. Our calculated linear functions, showing the growth dynamics of the ITA by pediatric ages, may be helpful in estimating its dimension.

Interthalamic Adhesion: Can it be used to Diagnose Idiopathic Intracranial Hypertension?

OBJECTIVE: This retrospective study aimed at determining the dimension of the interthalamic adhesion (ITA) in patients with the idiopathic intracranial hypertension (IIH) for assisting in preoperative radiologic diagnosis. METHODS: The study universe consisted of magnetic resonance images of 20 patients with IIH (age: 22.70 ± 4.04 years, sex: 14 females and 6 males) and 20 normal subjects (age 22.30± 2.94 years, sex: 14 females and 6 males). To determine the morphology of ITA, its height (vertical diameter) and width (horizontal diameter) were measured on the coronal and axial planes, respectively. RESULTS: The height and width of ITA in IIH were measured as 2.58 ± 0.71 mm (range: 1.40-4.20 mm) and 2.73 ± 0.77 mm (range: 1.70-4.40 mm), respectively. Its height and width in controls were measured as 4.99 ± 1.04 mm (range: 2.70-6.30 mm) and 4.92 ± 1.11 mm (range: 2.60-6.50 mm), respectively. ITA height and width in IIH was significantly smaller compared with controls (P < 0.001). For an arbitrary cutoff of 3.85 mm, the sensitivity of the height of ITA was 85% with 95% specificity. For an arbitrary cutoff of 4.45 mm, the sensitivity of the width of ITA was 75% with 100% specificity. CONCLUSIONS: The height and width of ITA are approximately 50% smaller in IIH than controls; therefore alterations in the dimension of ITA may be a valuable radiologic sign for the diagnosis of IIH.

Changes in Callosal Angle and Evans' Index After Placing a Lumboperitoneal Shunt in Patients with Idiopathic-Normal- Pressure Hydrocephalus.

AIM: To evaluate changes in the Evans? index (EI) and callosal angle (CA) in patients who underwent lumboperitoneal (LP) shunting for idiopathic normal pressure hydrocephalus (INPH) and whose symptoms improved post-operatively. MATERIAL AND METHODS: We retrospectively analysed patients who were clinically and radiologically diagnosed with INPH and treated with an LP shunt between 2010 and 2020. In all patients, we performed radiological imaging with EI and CA measurements and completed clinical assessments, including Mini-Mental State Examination (MMSE) and cognitive, urinary continence, balance and 10-m walking tests, preoperatively and post-operatively (less than 1 year later). Results were compared by statistical analyses. RESULTS: We evaluated 42 patients who received an LP shunt for INPH and had cranial magnetic resonance imaging (MRI) performed within the first 2 months after surgery. When the pre-operative and post-operative MRIs of the patients were compared, a statistically significant decrease was found in EI and CA measurements (p < .001, for each). A statistically significant improvement was found in clinical tests. Post-op early radiological images predicted recovery of the gait-balance function and urinary incontinence (p < .001) but did not predict recovery of dementia (p=.06). CONCLUSION: Radiological and clinical improvements are expected after the placement of ventriculoperitoneal (VP) or LP shunts in patients with INPH. Radiological measurements after an LP shunt in patients with INPH have not been reported in the literature. In the current study, radiological measurements after LP shunt placement were evaluated for the first time in patients with INPH. Significant changes in EI and CA after LP shunt placement may indicate whether patients will benefit clinically from an LP shunt during follow-up. A significant decrease in CA and EI measurements in the early period may be a marker for whether patients with INPH will show signs of clinical improvement and benefit from an LP shunt.

Isolated Lumbar Atypical Choroid Plexus Papilloma: A Case Report.

AIM: To report the first case of an isolated lumbar grade II atypical choroid plexus papilloma (CPP). CASE REPORT: A 42-year-old man was admitted to the hospital because of back and leg pain. No urinary or rectal dysfunction was detected. Lumbar magnetic resonance imaging (MRI) showed a well-circumscribed, contrast-enhancing, intradural extramedullary mass at L2-3. He underwent L2 and L3 partial laminectomies for tumor resection and complete resection was achieved without causing neurological deficit. Histopathologic examination of the tumor resulted in a diagnosis of grade II atypical CPP. The Ki-67 staining index was 7%. No lesion was detected on postoperative craniospinal MRI. CONCLUSION: Isolated lumbar atypical CPP in the lumbar region has not been previously reported. In the presence of a single spinal lesion, the diagnosis of CPP should be considered. Unlike metastatic and synchronous tumors, the pathogenesis of isolated choroid plexus tumors within the spinal canal has not been explained.

Neuroactive Peptide Nanofibers for Regeneration of Spinal Cord after Injury.

The highly complex nature of spinal cord injuries (SCIs) requires design of novel biomaterials that can stimulate cellular regeneration and functional recovery. Promising SCI treatments use biomaterial scaffolds, which provide bioactive cues to the cells in order to trigger neural regeneration in the spinal cord. In this work, the use of peptide nanofibers is demonstrated, presenting protein binding and cellular adhesion epitopes in a rat model of SCI. The self-assembling peptide molecules are designed to form nanofibers, which display heparan sulfate mimetic and laminin mimetic epitopes to the cells in the spinal cord. These neuroactive nanofibers are found to support adhesion and viability of dorsal root ganglion neurons as well as neurite outgrowth in vitro and enhance tissue integrity after 6 weeks of injury in vivo. Treatment with the peptide nanofiber scaffolds also show significant behavioral improvement. These results demonstrate that it is possible to facilitate regeneration especially in the white matter of the spinal cord, which is usually damaged during the accidents using bioactive 3D nanostructures displaying high densities of laminin and heparan sulfate-mimetic epitopes on their surfaces.

Endoscopic Anatomy and a Safe Surgical Corridor to the Anterior Skull Base.

OBJECTIVE: We describe the possibility to create precise preoperative planning for endonasal endoscopic approaches to the anterior skull base by overlapping endoscopic and radiologic anatomy. The important anatomic structures were marked. Morphometric measurements between these anatomic landmarks were performed endoscopically and compared with radiologic measurements of the same areas to ensure result compatibility. METHODS: Seven cadaver heads injected intravascularly with colored silicone were used for this study. Thin-section brain and paranasal sinus computed tomography scans were obtained on all cadavers. Using 0-degree rigid endoscopes and endonasal endoscopic surgical instruments, the anterior skull base was examined binostrally in all cadavers. Bilateral middle turbinates were identified and preserved. Next, an inferior uncinectomy and middle meatal antrostomy were performed. After performing a frontal antrostomy, bilateral anterior and posterior ethmoidal cells were opened and the skull base was identified and followed to the posterior wall of the frontal sinus. A transnasal transethmoidal sphenoidotomy was done with full exposure to the entire anterior skull base. RESULTS: The anatomic landmarks for endonasal endoscopic skull base approaches were distinguished and measurements were made. The anterior skull base was divided into 3 compartments: anterior (area between the posterior inferior border of the frontal sinus and the course of anterior ethmoidal artery), middle (area between the course of the anterior ethmoidal artery and that of the posterior ethmoidal artery [PEA]), and posterior (area between the course of the PEA and the attachment point of the anterior border of the sphenoid sinus to the skull base) compartments. The distances between important anatomic markers and endoscopic depth measurements of this area were measured. CONCLUSION: During endonasal endoscopic anterior skull base surgery, the area between the anterior border of the sphenoid sinus and PEA artery was safe as the first dissection zone. Preoperative radiologic width and depth measurements facilitate orientation to the endoscopic anatomy during surgery and help predict the endonasal surgical corridor anatomy preoperatively.

Timing of Shunt Insertion in Children with Neural Tube Defects and Hydrocephalus: A Clinical Study.

AIM: To define the optimal time of shunt insertion in patients with neural tube defects and hydrocephalus. MATERIAL AND METHODS: In total, 71 patients who underwent operation for neural tube defects and hydrocephalus were retrospectively evaluated between 2012 and 2018. The first group comprised 43 patients who underwent operation at different times (in 10 days after the repair of defect), and the second group comprised 28 patients who underwent operation at the same time. Ruptured and unruptured sacs were immediately considered and operated within 72 hours. RESULTS: In the first group, 43 patients underwent operation for neural tube defect after birth. Ventriculoperitoneal shunt insertion was performed 10 days after wound healing. Five (11.6%) patients were diagnosed with meningitis on follow-up. Shunt infection or meningitis was not observed on follow-up in the second group, which comprised patients who underwent operation at the same time. CONCLUSION: The lowest complication rate existed in hydrocephalus management when shunt insertion and myelomeningocele repair procedures were performed at the same time.

Collagen Peptide Presenting Nanofibrous Scaffold for Intervertebral Disc Regeneration.

Lower back pain (LBP) is a prevalent spinal symptom at the lumbar region of the spine, which severely effects quality of life and constitutes the number one cause of occupational disability. Degeneration of the intervertebral disc (IVD) is one of the well-known causes contributing to the LBP. Therapeutic biomaterials inducing IVD regeneration are promising candidates for IVD degeneration treatments. Here, we demonstrate a collagen peptide presenting nanofiber scaffold to mimic the structure and function of the natural extracellular matrix of the tissue for IVD regeneration. The collagen peptide presenting nanofiber was designed by using a Pro-Hyp-Gly (POG) peptide sequence on a self-assembling peptide amphiphile molecule, which assembled into nanofibers forming scaffolds. Injection of collagen peptide presenting peptide nanofiber scaffold into the degenerated rabbit IVDs induced more glycosaminoglycan and collagen deposition compared to controls. Functional recovery of the tissue was evaluated by degeneration index score, where the bioactive scaffold was shown to provide functional recovery of the IVD degeneration. These results showed that the collagen peptide presenting nanofiber scaffold can prevent the progression of IVD degeneration and provide further functional recovery of the tissue.

Effect of Riluzole on Spinal Cord Regeneration with Hemisection Method Before Injury.

OBJECTIVE: The pathophysiology of spinal cord injury (SCI) with the information obtained to date has not been elucidated fully. A safe drug or treatment protocol that results in cell regeneration for SCI remains unknown. Neuroprotective and neuroregenerative effects of riluzole, administered after a SCI, have been shown in experimental studies. This study aimed to investigate the effect of riluzole on neural regeneration in a rat SCI model. METHODS: Thirty-two rats were divided into 8 groups, with 4 rats in each group. Hemisection method was performed after T7-T9 laminectomy. Rats were intraperitoneally aministered with riluzole (6 mg/kg). Locomotor recovery of the rats was assessed at 1 day, and 1, 2, 3, and 4 weeks after the 21-point Basso, Beattie, and Bresnahan test. Subsequently, the spinal cords of the rats were scored according to a semiquantitative grading system using a light microscope, and the numbers of myelinated axons, neurons, and glial cells were calculated. RESULTS: Basso, Beattie, and Bresnahan test changes were statistically significant when groups 4-6 and 8 were compared with the other groups (P < 0.05, P < 0.00625). The results of the numbers of neurons, glial cells, and myelinated axons were statistically significant. Especially group 8, in which riluzole was administered 5 days before injury, more positive clinical and histopathologic results were obtained. CONCLUSIONS: Riluzole treatment is more effective when provided before injury. Riluzole may contribute to functional recovery when used in the preoperative period in patients who are at a high risk for permanent neurologic deficit.