QEEG findings in nonsyndromic sagittal craniosynostosis.

Despite the undertaken treatment, children with nonsyndromic sagittal craniosynostosis (NSC) are burdened with problems with speech development, visuospatial and other cognitive deficits. The electroencephalographic assessment has not influenced the diagnostics and treatment strategy of craniosynostosis so far but the introduction of quantitative EEG (QEEG) protocols renewed an interest in the functional aspect of this disease. In this study we retrospectively assessed the QEEG records of 25 children with NSC aged 1-18 months (mean age 9.62 months) before and after surgery. In each case, the amplitude, interhemispheric (ICoh) and intrahemispheric (HCoh) coherence indices were calculated. Obtained data were compared to age-matched control group of 25 normocephalic children. Children with NSC presented significantly lower values of amplitudes and intrahemispheric coherence in occipital, posterior parietal and posterior temporal regions than normocephalic children. The values of amplitudes, ICoh and HCoh in pre- and postoperative QEEG records mostly remained unchanged, with a slight improvement in HCoh in centro-parietal area. These findings suggest that NSC children present their own QEEG profile. The operative treatment improves an intrahemispheric connectivity, but there still exists a significant difference in the occipitotemporal, frontotemporal and centro-frontal areas, which may be considered as a functional substrate of reported speech and neurocognitive problems. QEEG findings in nonsyndromic sagittal craniosynostosis.

The Accuracy of Classification Systems in Nonsyndromic Sagittal Craniosynostosis.

Numerous classification systems of nonsyndromic sagittal craniosynostosis (NSC) are applied but none has gained a wide acceptance, since each classification is focused on distinct aspects. The aim of the study was to assess the accuracy of 4 classifications of NSC discussed in the literature by defining the associations among the classifications, individual features (sex, age, cranial index), and objective morphologic criteria (frontal bossing, retrocoronal constriction, sagittal ridge, and occipital bulleting). The study was conducted on anonymized thin-cut CT scans of 133 children with NSC 1 to 12 months old (mean age 5.42 mo). The type of cranial dysmorphology was assessed using 4 classification systems, focusing on skull shape, pattern of sagittal suture closure (Heuzé classification), deformation of skull vault (Sakamoto classification), and a single-dominant feature (David classification). Each patient was also independently investigated for the presence of morphologic criteria. A multivariate analysis was performed to explore the relations among the classifications and assess their accuracy. In the analyzed cohort sphenocephaly (38.3%), CFF type by Heuzé (30.8%), type I by Sakamoto (72.9%), and a central type by David (42.9%) were dominant findings. Regarding the morphologic criteria, frontal bossing was observed the most frequently (91.7%). The age of patients and cranial index differed significantly among the shapes of skull and David classifications ( P <0.001). The shape-based system showed the strongest correlation with other classifications and with measurable variables. Other classifications have much in common and some overlap, but none of them constitutes a standalone system to define all aspects of cranial dysmorphology in NSC.

Radiologic evaluation and clinical assessment of facial sinus in adults and children - computed tomography study.

OBJECTIVE: The facial sinus is a recess of the lateral retrotympanum located between the chorda tympani (ChT) and facial nerve (FN). Chronic otitis media with cholesteatoma often spreads from the pars flaccida to the facial sinus (FS). In stapedotomy, if an unfavorable ChT type is encountered, there is a need for removal of bone between the ChT and FN. The aim of the study was to assess FSs in adults and children according to Alicandri-Ciufelli classification, to measure FS width and depth in computed tomography scans, evaluate the correlation between measurements and different types of facial sinuses, and provide a clinical context of these findings. METHODS: Cone Beam Computed Tomography (CBCT) of 130 adults and High Resolution Computed Tomography of 140 children were reviewed. The type of facial sinus was assessed according to Alicardi-Ciufelli's classification in different age groups. Width of entrance to facial sinus (FSW) and depth of FS (FSD) were evaluated among age groups. RESULTS: Type A of FS is dominant in both adult and children populations included in the study. The average depth of FS was 2.31±1.43 mm and 2.01±0.90 in children and adults respectively. The width of FS was 3.99±0.69 and 3.39±0.98 in children and adults respectively. The depth of FS (FSD) presented significant deviations (ANOVA, p<0.05) among all three types and age groups. In 116/540 (21.5%) cases the value of FSD was below 1 mm. CONCLUSION: The qualitative classification of facial sinuses into types A, B and C, introduced by Alicandri-Ciufelli and al. is justified by statistically significant differences of depth between individual types of tympanic sinuses. Type A sinuses may be extremely shallow (<1 mm - As) or normal (>1 mm - An). Preoperative assessment of CT scans of the temporal bones gives crucial information about type and size of facial sinus. It may increase the safety of surgeries in this area and play a role in choosing an optimal approach and surgical tools.

Radiomorphologic profiles of nonsyndromic sagittal craniosynostosis.

PURPOSE: Numerous classification systems of nonsyndromic sagittal craniosynostosis (NSC) are applied but none has gained a wide acceptance, since each classification is focused on distinct aspects of cranial dysmorphology. The goal of this study was to depict the most common combinations of radiomorphologic characteristics of NSC and to separate groups where the patients were morphologically similar to one another and at the same time significantly different from others. METHODS: The study was conducted on anonymized thin-cut CT scans of 131 children with NSC aged 1-12 months (mean age 5.42 months). The type of cranial dysmorphology was assessed using four criteria: skull shape, pattern of sagittal suture fusion, morphologic features and cerebrospinal fluid (CSF) spaces alterations. After assigning the categories, an unsupervised k-modes clustering algorithm was applied to identify distinct patients clusters representing radiomorphologic profiles determined by investigated characteristics. RESULTS: Cluster analysis revealed three distinct radiomorphologic profiles including the most common combinations of features. The profiles were not influenced by sex nor age but were significantly determined by skull shape (V = 0.58, P < 0.0001), morphologic features (V = 0.50, P < 0.0001) and pattern of sagittal suture fusion (V = 0.47, P < 0.0001). CSF alterations did not significantly correlate with the profiles (P = 0.3585). CONCLUSION: NSC is a mosaic of radiologic and morphologic features. The internal diversity of NSC results in dissimilar groups of patients defined by unique combinations of radiomorphologic characteristics, from which the skull shape is the most differentiating factor. Radiomorphologic profiles support the idea of clinical trials targeted at more selective outcomes assessment.

Meningovertebral ligaments could be a barrier for migration of a herniated intervertebral disc: An anatomical study.

Purpose: Intervertebral disc degeneration can manifest as sequestration. In most cases, the material could be found ipsilateral to the annular tear; however, a contralateral migration is also possible. We present an anatomical description of anterior meningovertebral ligaments (MVLs) as a possible barrier for disc migration. Methods: Anatomical dissection of 20 fresh human cadavers was carried out. Complete lumbar laminectomies with facetectomies were performed. All lumbar segments were exposed. Morphologic and morphometric descriptions of anterior MVLs were presented, with special attention to possible routes of herniated disc migration. Results: Anterior MVLs were present in all cases. They were divided in three separate groups: medial, lateral, and attached to the nerve roots. The medial group was the thickest, its mean length was 26.2 ± 1.2 mm, and it had no attachment to the disc in 51% of cases. The lateral group was less firm than the medial group, its mean length was 26.9 ± 1.0 mm, and it had no relation with the disc in 47% of cases. Ligaments related to the nerve root were the most delicate and always attached to the intervertebral disc. Their mean length was 14.9 ± 1.8 mm. Conclusions: The medial group of anterior MVLs are strong connective tissue bands dividing the anterior epidural space. The lateral group is more delicate, and in most cases, lateral MVLs lack annular attachment. MVLs could be an anatomical barrier for disc migration in particular cases.

The foramen magnum in scaphocephaly.

PURPOSE: The foramen magnum (FM) presents various alterations in craniosynostoses, such as brachycephaly or Crouzon syndrome. However, to date, no study has been devoted to its morphology and morphometry in scaphocephaly, which is the most common of cranial deformities resulting from premature fusion of cranial sutures. METHODS: We assessed the morphology and morphometry of FM using preoperative thin-cut CT scans of 107 children with non-syndromic sagittal craniosynostosis aged 1-12 months (mean age 5.38 months). A series of sagittal and transverse dimensions were taken and the FM area was calculated in each case. Obtained data were compared to the age-matched control group of 101 normocephalic children. RESULTS: Dolichotrematous type of FM was dominant in the scaphocephaly group and observed in 63/107 cases (58.9%). The mean FM area in the scaphocephaly group was 519.64 mm2 and was significantly smaller compared to the control group (p = 0.0011). The transverse diameter and anterior sagittal diameter were also significantly smaller (p = 0.0112 and p = 0.0003, respectively). CONCLUSION: The area of FM in scaphocephaly is smaller compared to normal individuals. This is associated with a significant reduction of the width of FM in children with sagittal craniosynostosis. FM in scaphocephaly is larger than in other reported series of children with brachycephaly or Crouzon syndrome.

Photo-Dependent Reflex Seizures-A Scoping Review with Proposal of Classification.

Children and adolescents are the largest at-risk group for the appearance of reflex seizures or epilepsy syndromes with a photoparoxysmal response. The aim of this study was to present an overview of the literature regarding photo-dependent reflex seizures. Epilepsy with seizures provoked by intermittent light stimulation is a distinct group of epilepsies; therefore, we focused on reflex seizures provoked by different factors whose common feature is the patient's response to intermittent photic stimulation. A qualitative search of PubMed/MEDLINE, Scopus, EBSCO, and Cochrane Library electronic databases for selected terms was carried out for scientific articles published up to May 2020 outlining the outcomes of control, observational, and case studies. This scoping review was developed and followed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews. The review of the qualitative evidence for the synthesis of photosensitive epilepsy allowed us to distinguish the following categories: light-induced seizures and light-deprived seizures. Differentiating between intermittent photic stimulation-related epilepsy syndromes and seizures is essential in order to determine the length of appropriate treatment. Photo-dependent reflex seizures make up the majority of this type of disorder among reflex seizures. Since there are many seizures provoking factors in the world around us, it is important to distinguish amongst them in order to be able to protect the patient exposed to this factor. It is recommended that the photostimulation procedure be performed during a routine electroencephalogram study.

Anatomy podcasts for medical education.

The implementation of podcasts as a complementary educational activity increased over the past year due to the Covid-19 pandemic. Being an alternative channel for transmission of anatomical knowledge, the on-demand audio broadcasts became an intriguing medium for both students and educators. This paper presents the results of a questionnaire study on the evaluation of an audio podcast designed specifically for the first-year medical students as an innovative and optional component of the human anatomy course. The audience expressed their opinions in four categories: engagement in listening to the podcast, content and preferences, technical level and perspectives of using the podcast in further years of medical studies. Despite the non-compulsory nature of the podcast, the listenership reached the level of 45%. In the study, 1608 listeners had access to the survey and the overall response rate was 35.9%. Based on the analysis, the attitude and preferences of the listeners were demonstrated, including the preferred time of listening, length of the episodes, selection of topics, format of the broadcast, or the method of its delivery. Students also commented on the influence of the podcast on passing the final exam in anatomy and a concept of recording broadcasts in a foreign language. The presented data allowed the recognition of the needs of medical students and contributed to the improvement of the ongoing project. The paper presents the technical data and guidelines for educators willing to include this medium in the students' anatomical curriculum.

On the radiologic anatomy of pediatric sinus tympani: HRCT study.

OBJECTIVE: Sinus tympani (ST) is considered the most constant among retrotympanic recesses but it is of great anatomical variability in shape and relation to mastoid portion of facial nerve. ST is difficult to access when clearing the cholesteatoma or serving as a window for cochlear implantation. The objective was to describe morphology of ST and assess feasibility of retrofacial approach in children under 5 years old. METHODS: HRCT images of 150 children were reviewed. The type of sinus tympani was assessed according to Marchioni's classification. Width of entrance to sinus tympani (STW), depth of ST (STD), distance between the posterior semicircular canal and facial nerve (F-PSC), distance between the latter plane to the floor of ST at the right angle (P-ST) were measured. Width (HS-SS) and length (ML) of mastoid process were also measured. RESULTS: From 300 temporal bones analyzed, the most common type of ST was type B (59.3%), followed by type C (34.3%) and type A (6.3%). The average depth of ST was 3.38±1.04 mm (1.32-8.24 mm) and mean value of F-PSC (width of retrofacial approach) was 4.91±0.75. The depth of ST (STD) presented significant deviations (ANOVA, p<0.05) among all three types. The value of ML increased with age (very high correlation). CONCLUSION: Deep tympanic sinus (type C) is more frequent in children than in adult populations and it may suggest that pneumatization may affect the development of tympanic sinus final shape. Retrofacial approach can be used in selected pediatric patients after HRCT analysis.

The quantitative effect of blue lenses on pediatric photoparoxysmal response - An electroencephalographic cohort study.

PURPOSE: To determine and quantify the effect of blue lenses (Z1) on photosensitivity (PS) suppression in patients aged 5-18 years with and without epilepsy. METHODS: The retrospective cohort study was carried out in 100 pediatric patients aged 5-18 years with grade 4 PS assessed with EEG for medical indications. All EEG procedures were carried out and recordings assessed by two independent researchers. The study cohort was divided into groups with and without the diagnosis of epilepsy. The overall effect of the Z1 lenses on photoparoxysmal response (PPR) was determined by directly comparing the maximum discharge values in each patient without and with Z1 lenses in a within-subject design yielding the index of overall improvement (IOI). The differences in PS suppression by brain region and side were assessed by an additional between-subject comparison of age groups (below and above 14 years). Then, overall findings were compared with the PPR change criteria developed in 2006 by Capovilla (PPR disappearance, persistence, or attenuation) which warranted another subset analysis. Finally, in a between-subject design, we assessed whether the presence of epilepsy affects the intensity of PPR in children with PS, compared to non-epilepsy children. RESULTS: The IOI in the entire cohort was 66.1±2.5% (P<0.001). There were no significant differences in IOI between the left and right hemispheres, between the age groups, and between the epilepsy and non-epilepsy groups, despite some qualitative variation. With reference to literature findings, whereas median IOI were comparable in PPR disappearance and attenuation subsets, they differed significantly from the median IOI in the PPR persistence subset. CONCLUSION: Using Z1 lenses results in neither a complete PPR disappearance, nor a complete lack of effect. However, the correlation between the quantified PS suppression and the Z1 filter may be expected to become a valuable piece of information for both clinicians and manufacturers.

Method of creating 3D models of small caliber cerebral arteries basing on anatomical specimens.

The cerebral circulation is a common site of vascular lesions and concurrent hemodynamic accidents, which often lead to serious neurological disabilities. Recent advances in understanding pathogenesis, improving diagnostics and developing new treatment methods for these conditions result from an interdisciplinary approach to the problem - linking clinical sciences, basic medical sciences and hemodynamical analyses. Most common techniques used in such studies include computational fluid dynamics, which allows for development of 3D models of cerebral vasculature, basing on radiological studies. However, these methods remain flawed, mainly because of their spatial resolution, which is not high enough to visualize the smallest arterial branches (perforating branches) in the models. That leaves the perforators (<1.0 mm) out of most of the contemporary studies, whilst their clinical importance is widely recognized in clinical practice. Obstruction of these vessels by atherosclerotic plaques, thrombi or implantation of flow diverting stents may result in neurological complications such as paralysis or coma. Our research team has recently developed a new method of creating 3D models of the cerebral arterial system based on anatomical specimens and micro computed tomography (micro-CT). We have infused fresh brainstem vasculature specimens with contrast medium, subsequently scanned them using an industrial-grade micro-CT system and finally, created spatial models, which included branches of diameter less than 0.1 mm. None of the current methods have been able to produce models of detail as high as this, which allows us to presume, that our procedure may open up new opportunities for hemodynamical studies within cerebral circulation and beyond.

Acute platelet response to aneurysmal subarachnoid hemorrhage depends on severity and distribution of bleeding: an observational cohort study.

Microthrombosis after aneurysmal subarachnoid hemorrhage (aSAH) is considered to initiate neuroinflammation, vessel remodeling, and blood-brain barrier leakage. We aimed to verify the hypothesis that the intensity of thrombogenicity immediately after aSAH depends on the amount and distribution of extravasated blood. This observational cohort study included 37 consecutive aSAH patients admitted no longer than 24 h after ictus. Volumes of subarachnoid and intraventricular hemorrhages as well as the Subarachnoid Hemorrhage Early Brain Edema Scale (SEBES) score were calculated in each case. Platelet system status was described by platelet count (PLT), mean platelet volume (MPV), MPV to PLT ratio, and platelet-large cell ratio (P-LCR). Median hemorrhage volume amounted to 11.4 ml (interquartile range 2.8-26.8 ml). Patients with more severe hemorrhage had lower PLT and higher MPV to PLT ratio (ρ = - 0.49, p < .002; ρ = 0.50, p < .002, respectively). PLT decreased by 2.80 G/l per 1 ml of hemorrhage volume (95% CL 1.30-4.30, p < .001). Further analysis revealed that intraventricular hemorrhage volume was associated with P-LCR and MPV (ρ = 0.34, p < .039; ρ = 0.33, p < .048, respectively), whereas SAH volume with PLT and MPV:PLT ratio (ρ = - 0.40, p < .013; ρ = 0.41, p < .013, respectively). The odds of unfavorable neurological outcome increased 3.95 times per 1 fl of MPV (95% CI 1.19-13.12, p < .025). MPV was independently correlated with SEBES (ρ = 0.44, p < .006). This study demonstrated that the extent and distribution of aneurysmal subarachnoid hemorrhage are related to different types of acute platelet response, which may be interpreted as local and systemic thrombogenicity. Increased mean platelet volume measured in the acute phase of aSAH may identify patients at risk for unfavorable neurological outcomes and may serve as a marker of early brain injury.

Symmetry and interhemispheric propagation of paediatric photoparoxysmal response.

AIM OF THE STUDY: To investigate the speculated interhemispheric symmetry and the pattern of propagation of paediatric photoparoxysmal response. CLINICAL RATIONALE FOR THE STUDY: Quantitative analysis of the photoparoxysmal response (PPR) to intermittent photic stimulation is a promising method of assessing photosensitivity (PS). The pattern of PPR propagation underlies the model used for calculations. The generalisation of a discharge should correspond with the parameters objectively characterising the PPR in both cerebral hemispheres. However, to date no evidence of a postulated symmetry has been demonstrated. MATERIALS AND METHODS: Our analysis was performed by comparing the EEG amplitude and interhemispheric coherence (ICoh) in both hemispheres in 100 non-epileptic individuals of both sexes, aged 5-18 years, with PS grade IV (the PPR group) and without PS (the control group). The amplitude and ICoh values were recorded and analysed statistically. RESULTS: The distribution of amplitude values between the hemispheres was comparable in both groups, but was significantly different between the PPR group and the control group. Individual tracks of propagation revealed hemispheric symmetry. Interhemispheric coherence values were significantly higher in occipital, temporal and fronto-polar areas in children with PS. CONCLUSIONS AND CLINICAL IMPLICATIONS: This study provides objective evidence of interhemispheric symmetry in paediatric PPR, which supports the link with generalised seizures. Interhemispheric propagation is facilitated in children with PS, and propagation is more likely in the occipital and temporal regions.

Microtomographic morphometry of the stapedius muscle and its tendon.

The aim of this study was to evaluate the morphology of the stapedius muscle and its tendon with the use of microCT and to describe their anatomic relationship with facial nerve and incudostapedial joint. The study was performed on 16 fresh cadaveric temporal bones scanned in microtomography (microCT). Stapedius muscle and its tendon were identified in each set of images. The length of the medial and lateral border of the stapedius tendon (STL-med, STL-lat), width at the insertion to stapes (STW-s), at the point it emerges from the pyramidal eminence (STW-p) and in the half way from the pyramidal eminence to stapes (STW-m), and the length and the width of the belly of stapedius muscle (BSML and BSMW) were measured in modified axial plane. The shortest distance between the facial canal and incudostapedial joint (FN-isj), and between the facial canal and stapedius tendon (FN-st) were measured in the Pöschl plane. The average values of all distances measured were: STL-lat 1.29 ± 0.50 mm, STL-med 1.27 ± 0.44 mm, BSML 2.98 ± 0.51 mm, STW-s 0.47 ± 0.10 mm, STW-p 0.46 ± 0.12 mm, STW-m 0.35 ± 0.12 mm, BSMW 1.26 ± 0.29 mm, FN-isj 1.72 ± 0.33 mm, FN-st 1.35 ± 0.30 mm. The stapedius muscle complex consists of the tendon and the belly, and the border between them in microCT scans is not always evident. The distance between the facial nerve and the incudostapedial joint is greater than the distance between the facial nerve and the stapedius muscle tendon.

The radioanatomical assessment of the Körner's septum.

PURPOSE OF THE STUDY: Körner's septum (KS) is a developmental remnant formed at the junction of mastoid and temporal squama, representing the persistence of the petrosquamosal suture. During mastoid surgery, it could be taken as a false medial wall of the antrum so that the deeper cells might not be explored. The aim of the study was to assess a Körner's septum prevalence and to analyze its topography. METHODS: The study was performed on 80 sets of cone-beam computed tomography (CBCT) images of temporal bone (41 male, 39 female, 160 temporal bones). Körner's septum was identified and its thickness was measured on axial sections at three points: at the level of superior semicircular canal (SCC), at the level of head of malleus (HM) and at the level of tympanic sinus (TS). RESULTS: KS was encountered at least in one point of measurements in 50 out of 80 sets of CBCT images (62.5%). The average thickness at the level of SCC was 0.87 ± 0.34 mm, at the level of HM was 0.99 ± 0.37 mm and at the level of TS was 0.52 ± 0.17 mm. CONCLUSIONS: Körner's septum is a common structure in the temporal bone-air cell complex. It is more often encountered in men. In half of the patients, it occurs bilaterally. However, in most of the cases it is incomplete with anterior and superior portions being the most constant.

A case of symmetric retrograde thromboembolic cerebral infarction in an 8-year-old child due to arterial thoracic outlet syndrome.

Arterial type of thoracic outlet syndrome belongs to the most unusual mechanisms of stroke in children in the first decade of life. We present a case diagnosed for bilateral and symmetric changes due to retrograde thromboembolic phenomenon. Regarding the age of the patient, the appropriate diagnostics and management are still a matter of debate in pediatric and neurological literature.

Postnatal development of the subarcuate fossa and subarcuate canaliculus-a computed tomographic study.

PURPOSE: The subarcuate fossa (SF) is an anatomical structure situated on posterior wall of the petrous part of the temporal bone. In older children and adults, SF is a shallow depression and the subarcuate canaliculus starts within it. Awareness of postnatal changing morphology of this region is important especially for otosurgeon. The aim of this paper is to characterize both SF and SC by means of anatomical and radiological methods. METHODS: The study was carried out on CT scans of 101 children, aged 1-60 months. Length of the pyramid (PL), the distance between the anterior semicircular canal (ASC) and the pyramidal apex (PLM), the outer diameter of ASC (ASCD), width under ASC (SFWM), the distance between the fundus of SF and ASC (SFLL), the maximal width of SF lateral to ASC (SFWL), the distance between the fundus of SF and posterior surface of the pyramid (SFL) were measured. RESULTS: Average value of all measured distances: PL 52.14 ± 6.32 mm and PLM 25.73 ± 3.47 mm (raised with age); ASCD 8.63 ± 0.67 mm; SFWM 0.95 ± 1.24 mm; SFLL 1.07 ± 1.63 mm; SFWL 0.76 ± 1.19 mm; SFL 3.60 ± 2.50 mm. CONCLUSIONS: Petrous part of the temporal bone grows with age up to 5 years old, whereas ASC does not. SF diminishes with age: lateral to ASC is well developed in newborns and infants (up to first year), rapidly diminishes in children aged 1-2 years and is totally absent in children > 2 years. SF medial to ASC is constant and diminishes with age. In children older than 3 years morphology of SF is similar to adult.

Patterns of intrahemispheric propagation in pediatric photoparoxysmal response.

PURPOSE: The photoparoxysmal response (PPR) is the most important EEG indication of photosensitivity (PS). It may be elicited by intermittent photic stimulation (IPS). PS mostly affects young individuals, with adolescent females at greatest risk. The diagnosis of PS is based on visual EEG assessment. To date, no objective test of PS has been established. METHOD: Here we describe 89 individuals of both sexes, aged 5-18 years, epileptic and non-epileptic, in whom a PPR was elicited by IPS during a standard EEG procedure. The distribution of amplitude and intrahemispheric coherence indices were analyzed and, in each case, revealed a unique pattern of PPR propagation. RESULTS: A lateral (occipito-temporo-frontal) track was found in 52% of recordings, and 55% of individuals tested showed symmetric patterns. A bilateral pattern dominated in all age groups, all grades of PS, and across epileptic and non-epileptic groups. CONCLUSION: A symmetric, bilateral pattern is the most common type of PPR across genders and all ages, regardless of grade of PS and the presence of epilepsy. The results of this study show the current PPR classification in a new light and provide a basis for the concept of PPR lateralization based on objective, quantitative findings.

Traumatic intracranial displacement of the ventriculoperitoneal valve chamber in a child-a report of 2 cases.

We present two cases of traumatic intracranial migration of the ventriculoperitoneal (VPS) valve chamber without malfunction of the system. In both patients, a shunt reservoir was surgically repositioned without a burr hole expansion and with no implantation of a new VPS system. We discuss a role of a head trauma and repeated valve palpation in this rare complication.