Endoscopic biopsy of pineal tumors: two burr hole trans-foramen of Monro approach and endonasal trans-tuber cinereum approach.

INTRODUCTION: The pineal region is a challenging area for neurosurgeons due to its innate anatomical features, such as its deep location, surrounding large draining veins, and adjacent critical neural structures. DISCUSSION: There is a high proportion of malignant tumors in the pineal gland, especially in children, and they are frequently accompanied by obstructive hydrocephalus. These cases require that surgical procedures can make a pathological diagnosis to guide further treatment strategies and immediately resolve increased intracranial pressure. Simultaneous endoscopic third ventriculostomy and biopsy have been regarded as the first-line surgical intervention before establishing a definite treatment plan. However, it is not always successful because various factors affect the surgical procedures, such as the location and extent of the tumor, degree of ventriculomegaly, location and size of the massa intermedia, and size of the foramen of Monro. CONCLUSION: Here, we briefly reviewed the points to be considered in endoscopic biopsy of pineal tumors and introduced an alternative surgical procedure, the endoscopic endonasal trans-tuber cinereum approach, to surmount the anatomical hurdles.

Case Report: Lipoma of the Tuber Cinereum Mimicking a Pituitary Gland Abnormality in a Girl With Central Precocious Puberty.

Introduction: Magnetic Resonance Imaging (MRI) is the best approach to investigate the hypothalamic-pituitary region in children with central precocious puberty (CPP). Routine scanning is controversial in girls aged 6-8 year, due to the overwhelming prevalence of idiopathic forms and unrelated incidentalomas. Cerebral lipomas are rare and accidental findings, not usually expected in CPP. We report a girl with CPP and an unusually shaped posterior pituitary gland on SE-T1w sequences. Case Description: A 7.3-year-old female was referred for breast development started at age 7. Her past medical history and physical examination were unremarkable, apart from the Tanner stage 2 breast. X-ray of the left-hand revealed a bone age 2-years ahead of her chronological age, projecting her adult height prognosis below the mid parental height. LHRH test and pelvic ultrasound were suggestive for CPP. Routine brain MRI sequences, SE T1w and TSE T2w, showed the posterior pituitary bright spot increased in size and stretched upward. The finding was considered as an anatomical variant, in an otherwise normal brain imaging. Patient was started on treatment with GnRH analogue. At a thorough revaluation, imaging overlap with adipose tissue was suspected and a new MRI scan with 3D-fat-suppression T1w-VIBE sequences demonstrated a lipoma of the tuber cinereum, bordering a perfectly normal neurohypophysis. 3D-T2w-SPACE sequences, acquired at first MRI scan, would have provided a more correct interpretation if rightly considered. Conclusion: This is the first evidence, to our knowledge, of a cerebral lipoma mimicking pituitary gland abnormalities. Our experience highlights the importance of considering suprasellar lipomas in the MRI investigation of children with CPP, despite their rarity, should the T1w sequences show an unexpected pituitary shape. 3D-T2w SPACE sequences could be integrated into standard ones, especially when performing MRI routinely, to avoid potential misinterpretations.

Endoscopic management of an intrasellar arachnoid cyst through the tuber cinereum in an adult: a case report.

The transventricular endoscopic approach is an effective less invasive method for the management of symptomatic intrasellar arachnoid cysts in adults. The open area of the brain tissue defect in the infundibular recess caused by the upward compression of the cyst is a common target site for fenestration from the third ventricle. This report highlighted an alternative approach through the tuber cinereum (denoted as "trans-tuberal"), which enabled the treatment of symptomatic cases with a small opening for cyst fenestration in the infundibular recess.

Episodes of prolonged “trance-like state” in an infant with hypothalamic hamartoma

Hypothalamic hamartoma (HH) is one of the most common causes of central precocious puberty (CPP) in first few years of life. It can present with either seizures or CPP, although both manifestations coexist in the majority of the children. Gelastic seizures (GS), or laughing spells, are usually the first type of seizures seen in patients with HH. Although a wide variety of seizure types are known to occur in children with HH, GS are most common and consistent seizure type. The clinical presentation of HH may vary with the size and position of the mass, although large tumours typically present with both CPP and seizures. Although CPP can be managed with medical therapy, seizures can be very difficult to treat, even with multiple antiepileptic drugs. Noninvasive gamma knife surgery has been used with some success for the treatment of refractory epilepsy. We present a case of HH with very early onset seizures and CPP. The patient had an atypical form of seizures described by the parents as a "trance-like state" in which the patient had prolonged episodes of unresponsiveness lasting for hours with normal feedings during the episodes. GS occurred late in the course and were refractory to various combinations of antiepileptic drugs. A brain magnetic resonance imaging showed a large sessile HH (>20 mm). Later in the course of the disease, the patient experienced cognitive and behavioural problems. The patient underwent gamma knife surgery at nearly 5 years of age and experienced a modest response in seizure frequency. This case highlights the presentation of HH as a previously unreported seizure morphology described as a prolonged "trance-like state."

Different MRI-defined tuber types in tuberous sclerosis complex: Quantitative evaluation and association with disease manifestations.

BACKGROUND: Tuberous sclerosis complex (TSC) is a rare genetic disorder with multisystem involvement. A magnetic-resonance (MRI) based classification of tubers into types A, B and C has been proposed. However, the relationship between different tuber types and their quantitative characteristics, also the non-neurological manifestations of TSC remains unknown. AIMS: To quantitatively evaluate different MRI-defined tuber types and to explore their relationships with major disease manifestations in patients with tuberous sclerosis complex. METHODS: We performed quantitative manual assessment of tubers visible on T1W, T2W/FLAIR images and DW/ADC maps of 20 patients with TSC. Tubers were classified into types A, B and C based on their signal intensity on MRI. General clinical information and quantitative tuber characteristics were evaluated. Between-group comparisons were made using the nonparametric Mann-Whitney U test with Bonferroni correction. RESULTS: In total, 20 patients with 770 tubers were evaluated. Type A tubers were most numerous followed closely by Type B tubers, whereas Type C tubers were relatively rare. Tuber size was markedly different among the three tuber types: it increased from Type A to Type B to Type C. Infantile spasms, generalized-tonic clonic seizures, poor seizure control, cardiac rhabdomyomas, SEGA and developmental delay were not associated with quantitative tuber characteristics. Increased total Type B tuber load was associated with early onset epilepsy, while individually larger Type A and Type B tubers were associated with the presence angiomyolipoma (AML) and renal cysts. CONCLUSIONS: MRI-defined tuber types differ significantly in their size and number. Larger total Type B tuber load and larger individual Type A and Type B tubers were found to be most associated with early seizure onset and renal angiomyolipomas, respectively. One possible explanation for the observed differences in the clinical phenotype based on MRI-defined tuber types is not the intrinsic qualitative distinctions between different tuber types, but rather their individual size and total tuber load.

The tuber cinereum as a circumventricular organ: an anatomical study using magnetic resonance imaging.

PURPOSE: The tuber cinereum (TC) comprises the hypothalamic gray matter that forms the anterior portion of the third ventricle floor. However, since it has been rarely documented in previous neuroimaging investigations, the aim of the current study was to explore the morphology of the TC using magnetic resonance imaging (MRI). METHODS: Ninety-two patients were enrolled in this study. Following initial examination with conventional MRI sequences, a contrast study using intravenous gadolinium injection was performed in thin-sliced sections. RESULTS: The TC, which was commonly defined as a linear, enhancing structure on the midsagittal section, was identified in all 92 cases. In 83% of cases, the third ventricle floor had a gentle inflection at the junctional site between the median eminence and TC. The angle formed between the line parallel to the TC and the horizontal line showed considerable variability, which ranged from 0.5° to 56°. Furthermore, a non-enhancing segment of variable length was identified in the posterior-most TC. In 11% of cases, the midline TC was enhanced over the whole length. CONCLUSIONS: Since the most part of the midline TC was enhanced with intravenous gadolinium injection, it may function as a circumventricular organ. The TC should be evaluated with contrast sagittal MRI prior to performing surgery with management of the anterior third ventricle floor.

Symptomatic osteolipoma of the tuber cinereum masquerading as calcified retroclival mass.

We present a case of symptomatic osteolipoma of the tuber cinereum in a 51 year old male with rapid visual deterioration over several months leading to bilateral visual loss. Preoperatively the lesion masqueraded as a calcified retroclival mass. Intracranial osteolipomas are rare benign lesions that are usually asymptomatic and have an indolent course. Additionally, we discuss our intraoperative findings highlighting the technical challenges encountered along with a review of the English language literature on histologically proven intracranial osteolipomas.

First description of pharmacoresistant epilepsy due to independent bilateral hypothalamic hamartomas.

Hypothalamic hamartomas (HHs) are rare developmental malformations consisting of mixed neurons and glial cells, usually unilaterally attached to the tuber cinereum or mammillary bodies. We report on two patients, both suffering from pharmacoresistant epilepsy, behavioural and cognitive disturbances. Ictal and interictal electroencephalographic (EEG) abnormalities appeared bilaterally and multiregionally with right-sided preponderance. Magnetic-resonance imaging (MRI) revealed independent bilateral hypothalamic hamartomas, more prominently on the right side. Endoscopic surgery of the right HH was performed in each patient, resulting in a significant seizure reduction in both cases. To the best of our knowledge, there are no other reports of independent bilateral HHs in the literature.

Premio Sixto Obrador 2013. Modelo topográfico de 3 ejes para el tratamiento quirúrgico de los craneofaringiomas. Parte II: Evidencias anatómicas y neurorradiológicas que definen el modelo de clasificación de 3 ejes y su utilidad para predecir el riesgo quirúrgico individual / The 2013 Sixto Obrador Award. A triple-axis topographical model for surgical planning of craniopharyngiomas. Part II: Anatomical and neuroradiological evidence to define triple-axis topography and its usefulness in predicting individual surgical risk

INTRODUCCIÓN Y OBJETIVOS: Este estudio analiza las evidencias patológicas y de imagen de resonancia magnética que definen la topografía de los craneofaringiomas y permiten una clasificación de las lesiones según el riesgo de daño hipotalámico que estas asocian. MATERIAL Y MÉTODOS: Se ha realizado un análisis sistemático de los métodos de clasificación topográfica empleados en las series quirúrgicas de craneofaringiomas descritas en la literatura (n = 145 series, 4.588 craneofaringiomas). También se analizaron las relaciones topográficas de casos individuales intervenidos y bien descritos de la literatura (n = 224 casos) y de casos estudiados en autopsias (n = 201 casos). Finalmente, se analizaron y compararon los estudios prequirúrgicos y posquirúrgicos de imagen de resonancia magnética de craneofaringiomas bien descritos (n = 130) para establecer un modelo diagnóstico topográfico en 3 ejes de la lesión, que permite anticipar cualitativamente el riesgo quirúrgico asociado de daño hipotalámico. RESULTADOS: Las 2 principales variables pronósticas que definen la topografía del craneofaringioma son su posición con respecto al diafragma selar y la afectación del suelo del tercer ventrículo. Un modelo diagnóstico de 5 variables, que son: edad del paciente, existencia de hidrocefalia o de alteraciones del comportamiento, posición relativa de los hipotálamos y el valor del ángulo mamilar, permiten diferenciar craneofaringiomas supraselares que comprimen el tercer ventrículo (craneofaringiomas seudointraventriculares) de lesiones estrictamente intraventriculares o aquellas con un crecimiento primario en el suelo del tercer ventrículo (craneofaringiomas infundibulotuberales o no estrictamente intraventriculares). CONCLUSIONES: Un modelo de clasificación topográfica de los craneofaringiomas en 3 ejes que incluya el grado de infiltración del hipotálamo es útil para la planificación del abordaje y el grado de resección. Los craneofaringiomas infundibulotuberales representan un 42% de los casos y muestran una adherencia fuerte y circunferencial al suelo del tercer ventrículo, asociando un riesgo de daño hipotalámico del 50%. El abordaje transesfenoidal endoscópico permite valorar la adherencia tumoral hipotalámica bajo visión directa

INTRODUCTION AND OBJECTIVES: This study evaluates the pathological and magnetic resonance imaging evidence to define the precise topographical relationships of craniopharyngiomas and to classify these lesions according to the risks of hypothalamic injury associated with their removal. MATERIAL AND METHODS: An extensive, systematic analysis of the topographical classification models used in the surgical series of craniopharyngiomas reported in the literature(n = 145 series, 4,588 craniopharyngiomas) was performed. Topographical relationships of well-described operated craniopharyngiomas (n = 224 cases) and of non-operated cases reported in autopsies (n = 201 cases) were also analysed. Finally, preoperative and postoperative magnetic resonance imaging studies displayed in craniopharyngiomas reports (n = 130) were compared to develop a triple-axis model for the topographical classification of the selesions with qualitative information regarding the associated risk of hypothalamic injury. RESULTS: The 2 major variables with prognostic value to define the topography of a craniopharyngioma are its position relative to the sellar diaphragm and its degree of invasion of the third ventricle floor. A multivariate diagnostic model including 5 variables -patient age, presence of hydrocephalus and/or psychiatric symptoms, the relative position of the hypothalamus and the mammillary body angle- makes it possible to differentiate suprasellar craniopharyngiomas displacing the third ventricle upwards (pseudointraventricular craniopharyngiomas) from either strictly intraventricular craniopharyngiomas or lesions developing primarily within the third ventricle floor (infundibulo-tuberal or not strictly intraventricular craniopharyngiomas). CONCLUSIONS: A triple-axis topographical model for craniopharyngiomas that includes the degree of hypothalamus invasion is useful in planning the surgical approach and degree of resection. Infundibulo-tuberal craniopharyngiomas represent 42% of all cases. These lesions typically show tight, circumferential adhesion to the third ventricle floor, with their removal being associated with a 50% risk of hypothalamic injury. The endoscopically-assisted extended transsphenoidal approach provides a proper view to assess the degree and extension of craniopharyngioma adherence to the hypothalamus

Premio Sixto Obrador 2013. Modelo topográfico de 3 ejes para el tratamiento quirúrgico de los craneofaringiomas. Parte I: Evolución histórica del diagnóstico topográfico y métodos de clasificación de los craneofaringiomas / The 2013 Sixto Obrador Award. A triple-axis topographical model for surgical planning of craniopharyngiomas. Part I: Historical review of the topographical diagnosis and classification schemes of craniopharyngiomas

INTRODUCCIÓN Y OBJETIVOS Este estudio revisa la evolución histórica de los hallazgos patológicos, neurorradiológicos y quirúrgicos que han influido en el desarrollo de los conceptos sobre la topografía de los craneofaringiomas y en los diversos métodos de clasificación topográfica de estas lesiones. MATERIAL Y MÉTODOS Se ha realizado un análisis sistemático de los métodos de clasificación topográfica empleados en las series quirúrgicas de craneofaringiomas descritas en la literatura (n = 145 series, 4.588 craneofaringiomas), con el objetivo de describir los hallazgos anatómicos fundamentales que han guiado el desarrollo de las clasificaciones topográficas empleadas a lo largo de la historia. Estos hallazgos se han comparado con las relaciones topográficas de casos individuales bien descritos de craneofaringiomas intervenidos (n = 224 casos), así como de casos no operados estudiados en autopsias (n = 201 casos). RESULTADOS: Las 2 principales variables que definen la topografía de un craneofaringioma son su posición con respecto al diafragma selar y su grado de invasión del suelo del tercer ventrículo. Los tumores supraselares que desplazan hacia arriba el suelo del tercer ventrículo (craneofaringiomas seudointraventriculares) pueden extirparse totalmente de forma segura y deben distinguirse de los tumores que han crecido de forma primaria en el suelo del tercer ventrículo. CONCLUSIONES: Un modelo de clasificación topográfica de los craneofaringiomas en 3 ejes que incluya el grado de infiltración del hipotálamo es útil para la planificación del abordaje y el grado de resección. Los craneofaringiomas infundibulotuberales asocian el mayor riesgo de daño hipotalámico, en torno al 50%. El abordaje transesfenoidal endoscópico permite valorar la topografía de la lesión y su grado de adherencia tumoral hipotalámica bajo visión directa

INTRODUCTION AND OBJECTIVES: This study reviews the historical evolution of pathological, neuroradiological and surgical evidence that influenced the topographical concepts andclassification schemes of craniopharyngiomas. MATERIAL AND METHODS: An extensive, systematic analysis of the surgical series of craniopharyngiomas reported in the literature was performed (n= 145 series, 4,588 tumours) todescribe the fundamental anatomical findings guiding the topographical classification schemes used for this tumour throughout history. These findings were compared with topographical relationships reported for well-described operated craniopharyngiomas (n = 224 cases) as well as for non-operated cases studied in autopsies (n = 201 cases). RESULTS: Two major variables define the topography of a craniopharyngioma: its position relative to the sellar diaphragm and its degree of invasion of the third ventricle floor. Suprasellarlesions displacing the third ventricle floor upwards (pseudointraventricular craniopharyngiomas) are amenable to safe, radical resection and must be differentiated from lesions developing primarily within the third ventricle floor (infundibulo-tuberal or not strictly intraventricular craniopharyngiomas). The latter group typically shows tight, circumferential adhesion to the third ventricle floor and represents approximately 40% of all cases. CONCLUSIONS: A triple-axis topographical model for craniopharyngiomas that includes the degree of hypothalamus invasion is useful in planning surgical approach and degree of resection. The group of infundibulo-tuberal craniopharyngiomas associates the highest risk of hypothalamic injury (50%). The endoscopically-assisted extended transsphenoidal approach provides a proper view to assess the topography of the craniopharyngioma and its degree of adherence to the hypothalamus

Tuber cinereum proximity to critical major arteries: a morphometric imaging analysis relevant to endoscopic third ventriculostomy.

BACKGROUND: Arterial bleeding in the interpeduncular fossa is a dreaded complication of endoscopic third ventriculostomy (ETV). When the "safe zone" of the tuber cinereum (TC) is fenestrated, the basilar artery tip (BT) or its branches may be encountered below the third ventriclular floor. Major arterial injuries might be avoided by careful preoperative planning. We aimed to establish previously unavailable normal magnetic resonance imaging (MRI) and MR angiographic (MRA) morphometry and configuration of the BT and posterior cerebral artery P1 segments relative to the TC. METHODS: We analyzed images of 82 patients with non-dilated ventricles (mean Evans' index 0.26), and lying in a neutral head position (mean cervico-medullary angle 141°). We cross-referenced axial MRAs with sagittal MRIs to measure distances of BT and P1 segments from the TC, and to classify the location of the BT in the interpeduncular and suprasellar cisterns. We correlated the sagittal areas of these cisterns and patients' ages with the TC-to-artery distances using regression analysis. RESULTS: The BT, right P1 and left P1 segments were a mean 4.9 mm, 5.5 mm, and 5.7 mm respectively from the TC. Seventy-four percent of BTs were anterior to the mammillary bodies. These distances and locations did not correlate with age (mean 53 years) or size of basal cisterns. CONCLUSIONS: The normal BT and P1 segments are anatomically close to the TC and potentially at risk during ETV in adults of all ages. The new morphometric data presented, along with cross-referencing of preoperative multiplanar images, could help reduce vascular complications during ETV.

Precocious puberty produced by an osteolipoma of the tuber cinereum.

Central precocious puberty (CPP) is fairly common in girls. In most girls, the etiology for the CPP is unknown. Among the more rare causes of CPP in girls are central nervous system tumors and hamartomas. Osteolipoma of the tuber cinereum, which is the most commonly diagnosed at autopsy, has been reported as a cause of CPP. We describe an 8-year-old girl with central precocious puberty in whom MRI demonstrated a lesion compatible with osteolipoma. Her symptom was breast development that begun at age 7 years and 9 months. Her case history, laboratory studies and imaging are presented. Her puberty was rapidly progressive. She was treated successfully with a GnRHa (Triptorelin 3.75 mg IM q 4 weeks). Her case brings to the forefront the need to perform an MRI in children with rapidly progressing puberty.

Glial cell line-derived neurotrophic factor gene therapy ameliorates chronic hyperprolactinemia in senile rats.

Progressive dysfunction of hypothalamic tuberoinfundibular dopaminergic (TIDA) neurons during normal aging is associated in the female rat with chronic hyperprolactinemia. We assessed the effectiveness of glial cell line-derived neurotrophic factor (GDNF) gene therapy to restore TIDA neuron function in senile female rats and reverse their chronic hyperprolactinemia. Young (2.5 months) and senile (29 months) rats received a bilateral intrahypothalamic injection (10(10) pfu) of either an adenoviral vector expressing the gene for beta-galactosidase; (Y-betagal and S-betagal, respectively) or a vector expressing rat GDNF (Y-GDNF and S-GDNF, respectively). Transgenic GDNF levels in supernatants of GDNF adenovector-transduced N2a neuronal cell cultures were 25+/-4 ng/ml, as determined by bioassay. In the rats, serum prolactin (PRL) was measured at regular intervals. On day 17 animals were sacrificed and neuronal nuclear antigen (NeuN) and tyrosine hydroxylase (TH) immunoreactive cells counted in the arcuate-periventricular hypothalamic region. The S-GDNF but not the S-betagal rats, showed a significant reduction in body weight. The chronic hyperprolactinemia of the senile females was significantly ameliorated in the S-GDNF rats (P<0.05) but not in the S-betagal rats. Neither age nor GDNF induced significant changes in the number of NeuN and TH neurons. We conclude that transgenic GDNF ameliorates chronic hyperprolactinemia in aging female rats, probably by restoring TIDA neuron function.

Intratentorial osteochondrolipoma in a 9-year-old boy.

Intracranial osteolipomas and chondromas are rare benign tumors. Forty-five chondromas, mostly supratentorial, have been reported in the literature since 1981, with origins most commonly in the sellar regions. Twenty-one osteolipomas have been described to date, usually located near the tuber cinereum or the corpus callosum. The authors present a case of an osteochondrolipoma arising from the tentorium diagnosed in a pediatric patient at the age of 9 years. The case and treatment are discussed, and a review of the literature is provided.

Sudden death due to a colloid cyst of the third ventricle: report of three cases with a special sign at autopsy.

Colloid cysts of the third ventricle are rare benign cysts but they may be potentially life-threatening. Three cases of sudden death resulting from colloid cysts of the third ventricle are presented. The first and second cases were treated for migraine headaches. In the first case, the patient was a 24-year-old woman who presented to the hospital with a severe headache and was sent back home after medical treatment. Six hours later, she was found dead in her bed. The second case was a 21-year-old woman who experienced a severe headache, dizziness and vomiting 1 day prior to her death. She was transported to the hospital, where she was pronounced dead upon arrival. The third case was a 25-year-old man who experienced headaches and vomiting and was diagnosed with and medically treated for sinusitis. He lost consciousness and was taken to hospital, where he was pronounced dead on arrival. During the autopsy of all three cases, there was a grey transillumination area observed that occurred due to the stretching of tissue at the base of brain between the corpus mamillare and chiasma opticum. Dissection of the brain revealed a colloid cyst of the third ventricle. To avoid such fatal complications, prompt diagnosis using CT or MRI is essential in patients who have a long-standing history of intermittent headaches. During the autopsy of the sudden deaths of people with medical antecedents of headaches, if a grey color is observed between the chiasma opticum and the corpus mamillare in the base of the brain, a colloid cyst should be considered and this region should be dissected and examined carefully.

Colocalization of a carnosine-splitting enzyme, tissue carnosinase (CN2)/cytosolic non-specific dipeptidase 2 (CNDP2), with histidine decarboxylase in the tuberomammillary nucleus of the hypothalamus.

Carnosine is a naturally occurring dipeptide (beta-alanyl-l-histidine) present in mammalian tissues such as the brain and skeletal muscles. Carnosine is not only a radical scavenger but also a possible neurotransmitter-like molecule that regulates neuronal functions such as hypothalamic control of the autonomic nervous system. CN2 (CNDP2) is a cytosolic enzyme that can hydrolyze carnosine to yield l-histidine and beta-alanine. In order to understand the functions of carnosine and CN2 in the brain, we have investigated the immunohistochemical localization of CN2 in the hypothalamus. CN2-immunoreactivity was highly concentrated in neuronal cells in the dorsal part of the tuberomammillary nucleus of the posterior hypothalamus. Since the tuberomammillary nucleus is the exclusive origin of histaminergic neurons, we further investigated whether CN2 is present in the histaminergic neurons. We found that CN2-immunoreactivity was colocalized with that of histidine decarboxylase, which is the key enzyme for histamine biosynthesis specifically expressed in the histaminergic neurons of the tuberomammillary nucleus. These results suggest that CN2 is highly expressed in the histaminergic neurons in the tuberomammillary nucleus, implying that it may supply histidine to histaminergic neurons for histamine synthesis.