Polymorphous low-grade neuroepithelial tumor of the young (PLNTY): A case report with surgical and neuropathological differential diagnosis

BACKGROUND

Polymorphous low-grade neuroepithelial tumor of the young (PLNTY) is a rare entity of low-grade neuroepithelial tumors that primarily affects children and young adults. This distinct type of tumor presents unique challenges in diagnosis and management. With its relatively recent identification, researchers and clinicians are striving to understand the characteristics, behavior, and optimal treatment strategies. The symptoms are primarily related to seizures. However, PLNTY can be asymptomatic in some cases.

MATERIALS AND METHODS

This is a single-center case report study and a literature review paper. We reviewed a case treated and diagnosed at the Ankara University Faculty of Medicine, Department of Neurosurgery. The demographic data, clinical follow-ups, laboratory, and radiological data of the patients were assessed.

RESULTS

We present a 32-year-old male patient who has undergone gross total surgical excision with strict clinical follow-up. Clinical course as well as surgical data of the patient were observed and analyzed.

CONCLUSION

On imaging, morphologic resembling and indistinctive clinical course can be nonspecific, contributing to diagnostic uncertainties. This case report was written with the notion that rare diagnoses present an opportunity to understand the progression and patho-oncological factors that can pave the way for better treatment.

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.

A Novel Foley Catheter-Based Brain Retraction Method for the Interhemispheric Approach: Technical Considerations and an Illustrative Video

BACKGROUND

Management of interhemispheric pathologies requires surgical intervention through a restricted anatomical corridor ensconced within critical cerebral structures. The use of retractors to facilitate operative access may cause damage to cerebral tissue. The development of an innovative retraction technique designed to alleviate cerebral damage in such cases is imperative. In this study, we present a novel and gentle retraction method to facilitate the interhemisferic approach.

METHODS

We retrospectively examined data of 9 right-handed patients who underwent surgical resection of interhemispheric lesions between 2021 and 2022. All patients underwent surgery for the first time because of this pathology. All operative specimens were histologically confirmed. Clinical characteristics, operative details, and follow-up data were retrospectively analyzed.

RESULTS

The new retraction technique was successfully applied to 8 tumor patients and 1 patient with an aneurysm. Eight patients had an anterior interhemispheric approach, and 1 patient had a posterior interhemispheric approach. Complete surgical excision was achieved in all patients with no postoperative complications. Postoperative Gadolinium (Gd)-enhanced magnetic resonance imaging (MRI) showed no signs of ischemia or contusion. All patients exhibited significant improvements in their symptoms. An illustrative video that elucidates the removal of an interhemispheric epidermoid tumor, employing the anterior ipsilateral interhemispheric approach, featuring the novel retraction method.

CONCLUSIONS

The ideal retraction technique during the interhemispheric approach is still a challenge. Our novel retraction technique may help minimize brain parenchymal damage during surgical resection of interhemispheric lesions.

Anatomical features of the sphenoid ridge in the pediatric population

PURPOSE

To describe the relation of the sphenoid ridge (SR) with the surrounding anatomical structures in healthy children when approaching the anterior and middle fossae.

METHODS

Computed tomography of 180 pediatric patients (90 males / 90 females), aged 1-18 years were included the study. The size of the lesser wing (LW) and the distances of the LW to certain landmarks were measured.

RESULTS

The LW length was 28.48 ± 8.15 mm. The LW widths at the midline and the midpoint and lateral point of the SR were 7.78 ± 1.74 mm, 2.84 ± 0.81 mm, and 1.91 ± 0.64 mm, respectively. The distance between the midpoint of the SR and the crista galli was 28.22 ± 5.56 mm, and the distance between the crista alaris and internal auditory meatus was 51.73 ± 5.79 mm. The linear function was calculated as y = 18.748 + 1.024 × age for SR length, y = 6.046 + 0.182 × age for the midline width of SR, y = 2.367 + 0.050 × age for the midpoint width of SR, y = 1.249 + 0.069 × age for the crista alaris width, y = 21.727 + 0.683 × age for the distance between the SR midpoint and the crista galli, and y = 43.614 + 0.855 × age for the distance between the crista alaris and internal auditory meatus.

CONCLUSION

All measured parameters increased irregularly with advancing age. Furthermore, our regression equations representing the growth dynamics of SR may be used to estimate these parameters.

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.

Common Vertebral Fracture Level After the 2023 Turkey Earthquake: Thoracolumbar Junction - Due to Hyper-Flexed and Fixed Posture - at Triangle of Life Areas

AIM

To assess the frequency of thoracolumbar junction (TLJ) fractures (T10-L2) in survivors of the 2023 East Turkey earthquake.

MATERIAL AND METHODS

This single-center retrospective stdy evaluated 10 earthquake survivors, who were trapped under the rubble and rescued alive by rescue teams, and were assessed for spinal trauma after the earthquake in Eastern Turkey on February 6, 2023. All patients underwent full spinal magnetic resonance imaging and computed tomography examinations to determine the level of spinal fracture and decide the treatment methods.

RESULTS

All patients had sustained spinal fractures. Eight underwent surgery, while two were managed conservatively. Nine out of ten patients had TLJ fractures. Five patients had L1 fractures, four of them were treated surgically. Three patients had a T12 level fracture, two of whom were treated surgically. One patient with a T7-level fracture was treated surgically. Only one patient had multiple fractures (T12 and L2 levels) and was treated surgically.

CONCLUSION

The TLJ was the commonest vertebral fracture level as of the 2023 Turkey earthquake survivors in our study population. In the event of an earthquake, people tend to attain a fetal posture (fix and hyperflex the spine) when taking shelter in a narrow area (triangle of life). This position might place an excessive load on the TLJ, predisposing it to injuries.

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.

Analysis of the prechiasmatic sulcus in Chiari Malformation Type I

OBJECTIVE

This study aimed to assess morphological features of the prechiasmatic sulcus (PS) in Chiari Malformation Type I (CM-I).

METHODS

The study population consisted of computed tomography images of 42 CM-I patients (average age: 21.26±16.46 years; sex: 25 females and 17 males) and 58 normal subjects (average age: 28.12±22.60 years; sex: 29 females and 29 males). The measured parameters to determine the anatomy of PS were as follows: the planum length (PL), sulcal length (SL), sulcal angle (SA), and interoptic distance (IOD). Considering SL and SA measurements, PS was identified as four types: the narrow-steep-groove (NSG), narrow-flat-groove (NFG), wide-steep-groove (WSG), and wide-flat-groove (WFG).

RESULTS

SA was greater in CM-I (32.80±18.21°) compared to the control group (23.05±14.53°) (p=0.004), but the others were similar in both groups. Distribution ranking of PS types was found as NFG (31%) > NSG (26.20%) > WSG (23.80%) > WFG (19%) in CM-I group, while as WFG (37.90%) > WSG (20.70%) = NFG (20.70%) = NSG (20.70%) in the control group. Distribution rate of PS types relative to both groups showed that the classification system was not affected by CM-I (p=0.226).

CONCLUSIONS

SA value is approximately 25% greater in CM-I than the control; thus, CM-I subjects have more vertical groove. The percentage of narrow-type (NSG + NFG) in CM-I was higher than in the control group.

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.