Morphologic Variations of end Trunks of M1 Segment of Middle Cerebral Artery

Introduction: The middle cerebral artery is divided into four segments: proximal M1, insular M2, opercular M3 and cortical M4. M1 extends from the bifurcation point of ACI at ACA and ACM to the insula threshold, laterally from chiasma opticum, laterally from tractus opticus and caudally from trigonum olfactorium, directed laterally, dorsally and rostrally. Early division of the M1 segment into the final trunk is possible at any of the first points of the limb insulae. Material and methods: The study of the micromorphological and morphometric characteristics of the M1 segment was performed in 25 brain (50 ACM preparations) obtained from autopsy of both sexes of different ages without pathological changes. For the removal of the brain from the skull we used the usual technique of obduction. Results: This segment was arch-shaped, in 32 (64%) arteries, rarely S-shaped, in 12 (24%) arteries, much less straight alignment, in 6 (12%) arteries. The average length of the M1 segment of the S shape was 20.6 ± 3.31mm, with a 19.8 mm 4.41mm arch shape, while the straight shape was 16.9 ± 3.62mm. The average S-shaped diameter was 2.7 ± 0.51 mm, arched 2.6 ± 0.47 mm, straight form 2.6 ± 0.36 mm. Variations of M1 branching were: common in 38 cases, early branching in 12 cases, joint trunk with cortical branch in 9 cases, lateral cortical branch in 21 cases, final bifurcation in 24 cases, final trifurcation in 13 cases, duplication in 1 case and M1 accessory in just 1 case. Conclusion: True bifurcation refers to the division of the M1 segment into two final trunks. In cases where the strong joint cortical branch trunk divides from segment M1, while dividing into two terminal trunk immediately after ACM knee formation, it is described as false branching of M1 segment into three terminal branches.

Interdisziplinäres Management von Hypophysentumoren

Zusammenfassung. Raumforderungen in der Hypophyse haben unterschiedliche Entitäten. Am häufigsten kommen benigne Hypophysenvorderlappenadenome vor. Viele davon werden inzidentell entdeckt und sind asymptomatisch. Andere machen sich durch eine Beeinträchtigung der Hypophysenfunktion (Hypopituitarismus), eine gesteigerte Hormonsekretion (Prolaktinom, Akromegalie, Hypercortisolismus) oder durch neurologische Symptome (bitemporale Hemianopsie) bemerkbar. Die Abklärung beinhaltet eine endokrinologische Labordiagnostik sowie ein MRT der Hypophyse. Bei Nähe oder Kontakt zum Chiasma opticum ist zusätzlich eine Gesichtsfeldprüfung erforderlich. Bei symptomatischen Raumforderungen ist die Therapie der Wahl meist eine Operation über den transsphenoidalen Zugang. Eine Ausnahme bilden Prolaktinome, die in erster Linie medikamentös behandelt werden. Perioperativ ist eine engmaschige Kontrolle hinsichtlich eines Hypopituitarismus wichtig. Ein interdisziplinärer Austausch und das gemeinsame Festlegen des Prozederes ermöglichen die optimalste Betreuung der Patienten.

Modernes Management von Hypophysenadenomen – gegenwärtiger Stand in Diagnostik, Therapie und Nachsorge

Zusammenfassung. Hypophysenadenome (HA) sind gutartige Tumoren aus parenchymatösen Zellen des Hypopysenvorderlappens. Es wird zwischen endokrin-inaktiven HA und hormonsezernierenden HA differenziert. Die Symptomkonstellation ist abhängig von der hormonellen Über- oder Unterfunktion und dem durch das HA erzeugten Masseneffekt. Neben Kopfschmerzen präsentieren sich HA häufig mit Visusstörungen sowie Gesichtsfeldausfällen als Folge der Kompression des Chiasma opticum. Die chirurgische Resektion über einen transsphenoidalen Zugang ist die bevorzugte Therapieoption für symptomatische oder grössenprogrediente HA. Moderne Techniken wie intraoperative hochauflösende MR-Bildgebung unterstützen den Chirurgen in der maximal sicheren Resektion. Eine Sonderrolle spielen symptomatische Prolaktinome, die in erster Linie medikamentös mit Dopaminagonisten therapiert werden sollten. Aufgrund der Komplexität der Erkrankung ist eine interdisziplinäre Betreuung der Patienten durch Neurochirurgen und Endokrinologen in einem Zentrum mit hohen Fallzahlen empfohlen.

External anatomical structures of sparrowhawk (Accipiter nisus) encephalon

The aim of this study was to determine the external anatomical structures of encephalon in the sparrowhawk. For this purpose, four brains of sparrowhawk were assessed for morphometric measurements and external structures. The average weight of the sparrowhawk brain was approximately 3±0,2 g., while the mean length, width and dorsoventral thickness of sparrowhawk brain were measured 24±2 mm, 19±2 mm and 4±1 mm respectively. Dorsal appearance of the sparrowhawk encephalon showed two cerebral hemispheres, cerebellum, lobus opticus, flocculus and cranial part of medulla spinalis. In lateral aspect of encephalon, pars frontalis cerebri, pars parietalis cerebri, and pars occipitalis cerebri were observed on lateral surface of the hemispherium cerebri from rostral to caudal. The well developed lobus opticus bulged laterally. In ventral view, two small and underdeveloped bulbi olfactorii projected from the rostral pole of the each hemispheres. There was no olfactory tract behind the bulbus olfactorius. Area behind the chiasma opticum constituted the brainstem structures. The midbrain, pons, medulla oblongata and medulla spinalis situated from cranial to caudal respectively in the brainstem. But, there was no distinct borders between the midbrain, pons and medulla oblongata.

Intracranial oligodendroglioma with optic nerve infiltration in a Labrador retriever

A seven-year-old neutered male Labrador retriever was presented with behavioral changes and reduced vision. Neurological examination revealed blindness of the left eye with a positive pupillary light reflex and a decreased mental status. Blood and cerebrospinal fluid analyses showed no abnormalities. MRI revealed a deviant area located in the thalamic, hypothalamic and caudate nuclear regions. Invasion of the left optic nerve was also observed. The dog was euthanized after 38 days of palliative treatment. Necropsy showed a non-encapsulated extruding white lardaceous mass, with a diameter of 2 cm, in the white matter, located in the ventral thalamic region near the chiasma opticum, which extended along the left optic nerve. Histologically, neoplastic cells had a “fried egg” appearance. Immunolabelling for glial fibrillary acidic protein demonstrated the presence of numerous reactive astrocytes. The tumor was diagnosed as a low grade (II) intracranial oligodendroglioma with infiltration of the optic nerve.