Lacrimal gland enlargement and tear film changes in acromegaly patients: A controlled study

Purpose: Evaluation of the lacrimal gland volume (LGV) and its correlation with tear film functions, serum growth hormone (GH) and insulin-like growth factor-1 (IGF-1) levels in acromegaly patients compared to a control group was aimed

Dentate Nucleus: Connectivity-Based Anatomic Parcellation Based on Superior Cerebellar Peduncle Projections

OBJECTIVE: Projections from the dentate nucleus (DN) follow a certain organized course to upper levels. Crossing and noncrossing fibers of the dentatorubrothalamic (DRT) tract terminate in the red nucleus and thalamus and have various connections throughout the cerebral cortex. We aimed to establish the microsurgical anatomy of the DN in relation to its efferent connections to complement the increased recognition of its surgical importance and also to provide an insight into the network-associated symp-toms related to lesions and microsurgery in and around the region. METHODS: The cerebellum, DN, and superior cerebellar peduncle (SCP) en route to red nucleus were examined through fiber dissections from the anterior, posterior, and lateral sides to define the connections of the DN and its relationships with adjacent neural structures. RESULTS: The DN was anatomically divided into 4 areas based on its relation to the SCP; the lateral major, lateral anterosuperior, posteromedial, and anteromedial compart-ments. Most of the fibers originating from the lateral compartments were involved in the decussation of the SCP. The ventral fibers originating from the lateral ante-rosuperior compartment were exclusively involved in the decussation. The fibers from the posteromedial compart-ment ascended ipsilaterally and decussated, whereas most anteromedial fibers ascended ipsilaterally and did not participate in the decussation. CONCLUSIONS: Clarifying the anatomofunctional orga-n ization of the DN in relation to the SCP could improve microneurosurgical results by reducing the complication rates during infratentorial surgery in and around the n ucleus. The proposed compartmentalization would be a major step forward in this effort

Cervical Oblique Corpectomy: Revitalizing the Underused Surgical Approach With Step-By-Step Simulation in Cadavers

Recently, the World Federation of Neurosurgical Societies Spine committee recommended that additional research on cost-benefit analysis of various surgical approaches for cervical spondylotic myelopathy be carried out and their efficacy with longterm outcomes be compared. Unfortunately, it is highly probable that the oblique corpectomy (OC) will not be included in costbenefit investigations due to its infrequent application by neurosurgeons dealing with the spine. In this cadaveric study, head and necks of 5 adult human cadavers stained with colored latex and preserved in 70% alcohol solution were dissected under a tablemounted surgical microscope using 3x to 40x magnifications. The OC approach was performed to simulate real surgery, and the neurovascular structures encountered during the procedure and their relations with each other were examined. Oblique corpectomy was performed unilaterally, although neck dissections were performed bilaterally on 10 sides in all 5 cadavers. At each stage of the dissection, multiple three-dimensional photographs were obtained from different angles and distances. For an optimal OC, both the anterior spinal cord must be sufficiently decompressed and sufficient bone must be left in place to prevent instability in the cervical spine. Oblique corpectomy is a valid and potentially low cost alternative to other anterior and posterior approaches in the surgical treatment of cervical spondylotic myelopathy. However, meticulous cadaver studies are essential before starting real surgical practice on patients in order to perform it effectively and to avoid the risks of the technique

Microsurgical anatomy of the isthmic cingulum: a new white matter crossroad and neurosurgical implications in the posteromedial interhemispheric approaches and the glioma invasion patterns

AbtractThe dichotomy of the cingulum bundle into the dorsal supracallosal and ventral parahippocampal parts is widely accepted; however, the retrosplenial component with its multiple alternative connections has not been revealed. The aim of this study was to delineate the microsurgical anatomy of a connectionally transition zone, the isthmic cingulum, in relation to the posteromedial interhemispheric access to the atrium and discuss the relevant patterns of glioma invasion on the basis of its fiber connections. White matter (WM) fibers were dissected layer by layer in a medial-to-lateral, lateral-to-medial, and posterior-to-anterior fashion. All related tracts and their connections were generated using deterministic tractography. The magnetic resonance imaging (MRI) tractography findings were correlated with those of fiber dissection. A medial parieto-occipital approach to reach the atrium was performed with special emphasis on the cingulate isthmus and underlying WM connections. The isthmic cingulum, introduced as a retrosplenial connectional crossroad for the first time, displayed multiple connections to the splenium and the superior thalamic radiations. Another new finding was the demonstration of lateral hemispheric extension of the isthmic cingulum fibers through the base of the posterior part of the precuneus at the base of the parieto-occipital sulcus. The laterally crossing cingulum fibers were interconnected with three distinct association tracts: the middle longitudinal (MdLF), the inferior frontooccipital fasciculi (IFOF), and the claustro-cortical fibers (CCF). In the process of entry to the atrium during posterior interhemispheric approaches, the splenial and thalamic connections, as well as the laterally crossing fibers of the isthmic cingulum, were all in jeopardy. The connectional anatomy of the retrosplenial area is much more complicated than previously known. The isthmic cingulum connections may explain the concept of interhemispheric and medial to lateral cerebral hemisphere invasion patterns in medial parieto-occipital and posteromesial temporal gliomas. The isthmic cingulum is of key importance in posteromedial interhemispheric approaches to both: the atrium and the posterior mesial temporal lobe

Microsurgical anatomy and surgical exposure of the cerebellar peduncles

A better understanding of the surgical anatomy of the cerebellar peduncles in different surgical approaches and their relationship with other neural structures are delineated through cadaveric dissections. We aimed to revisit the surgical anatomy of the cerebellar peduncles to describe their courses along the brain stem and the cerebellum and revise their segmental classification in surgical areas exposed through different approaches. Stepwise fiber microdissection was performed along the cerebellar tentorial and suboccipital surfaces. Multiple surgical approaches in each of the cerebellar peduncles were compared in eight silicone-injected cadaveric whole heads to evaluate the peduncular exposure areas. From a neurosurgical point of view, the middle cerebellar peduncle (MCP) was divided into a proximal cisternal and a distal intracerebellar segments; the inferior cerebellar peduncle (ICP) into a ventricular segment followed by a posterior curve and a subsequent intracerebellar segment; the superior cerebellar peduncle (SCP) into an initial congregated, an intermediate intraventricular, and a distal intramesencephalic segment. Retrosigmoid and anterior petrosectomy approaches exposed the junction of the MCP segments; telovelar, supratonsillar, and lateral ICP approaches each reached different segments of ICP; paramedian supracerebellar infratentorial, suboccipital transtentorial, and combined posterior transpetrosal approaches displayed the predecussation SCP within the cerbellomesencephalic fissure, whereas the telovelar approach revealed the intraventricular SCP within the superolateral recess of the fourth ventricle. Better understanding of the microsurgical anatomy of the cerebellar peduncles in various surgical approaches and their exposure limits constitute the most critical aspect for the prevention of surgical morbidity during surgery in and around the pons and the upper medulla. Our findings help in evaluating radiological data and planning an operative procedure for cerebellar peduncles

Bashar ABUZAYED Endoscopic Endonasal Trans- sphenoidal Approach to the Sellar Region: Results of Endoscopic Dissection on 30 Cadavers Sellar Bölgeye Endoskopik Endonazal Trans-sfenoidal Yaklafl›m: 30 Kadavran›n Endoskopik Diseksiyon Sonuçlar›

ABSTRACT AIM: To recognize the endoscopic anatomy of the surgical corridor along the nasal cavity, sphenoidal sinus and the sellar area to delineate the pure endoscopic endonasal transsphenoidal approach (EETSA) to the region of the pituitary gland. MATERIAL and METHODS: The endoscopic anatomy of the nasal cavity, sphenoid sinus and the sellar region was studied in 30 fresh cadavers (mean age 42.1 / range 18-66) and dissections were performed in a stepwise manner to simulate EETSA to the sellar region. RESULTS: The sphenoid ostium, located 14.9 mm superior to the choana, was identified at the midpoint between the nasal septum and the superior turbinate in 23 specimens. The shape of the sphenoid ostium was linear (35%), fusiform (30%), oval(22%) or circular (13%). The mean width of the pituitary gland was 14.3 mm and the average minimum distance between the internal carotid arteries on both sides ranged between 13 to 22 mm. Following total hypophysectomy in 12 specimens, the width and length of diaphragma sellae was measured 10.83 and 5.83 mms respectively. CONCLUSION: This study documents that variations are common in nasal, sphenoidal and sellar phases of the trans-sphenoidal approach. Detailed knowledge of the basic anatomical relationships through the view of the endoscope and performing endoscopic dissections in large number of specimens will facilitate the endoscopic surgical procedures and decrease the rate of surgical complications. KEY WORDS: Endoscopic approach, Pituitary tumour, Transsphenoidal surgery, Skull-base surgery, Surgical anatomy ÖZ AMAÇ: Nazal kavite, sfenoidal sinüs ve sellar bölge boyunca uzanan cerrahi koridorun endoskopik anatomisini incelemek ve pituiter bez bölgesine endoskopik endonazal transfenoidal yaklaşımı (EETSY) uygulamak. YÖNTEM ve GEREÇ: Nazal kavite, sfenoid sinüs ve sellar bölge endoskopik anatomisi 30 taze kadavrada (ortalama yaş 42.1 / aralık: 18-66) çalışıldı ve aşama aşama diseksiyon yapılarak sellar bölgeye EETSY uygulandı. BULGULAR: Sfenoid ostiumun kohananın ortalama 14.9 mm superiorunda olduğu görüldü ve 23 spesimende nazal septum ve superior turbinatın arasında orta noktada tespit edildi.Sfenoid ostiumun şekli lineer(%35), fuziform(%30), oval(22%) veya sirküler(%13) olarak yorumlandı. Pituiter bezin ortalama genişliği 14.3 mm'di ve her iki tarafta internal karotid arterler arasındaki minimum ortalama mesafe 13 ila 22 mm arasında değişmekteydi. 12 spesimene uygulanan total hipofizektomi sonrasında diafragma sella'nın ortalama genişlik ve uzunluğu sırasıyla 10.83 ve 5.83 mm olarak ölçüldü. SONUÇ: Bu çalışma, transnazal transsfenoidal yaklaşımın nazal, sfenoidal ve sellar aşamalarında anatomik varyasyonların sık olduğunu göstermektedir. Endoskopik bakış açısından temel anatomik ilişkilerin detaylı bir şekilde bilinmesi ve çok miktarda spesimen üzerinde endoskopik diseksiyonların uygulanması endoskopik cerrahi uygulamaları kolaylaştıracak ve cerrahi komplikasyon yüzdesini de düşürecektir

Microsurgical endoscopy-assisted presigmoid retrolabyrinthine approach with mastoid bone drilling: an anatomical laboratory investigation

Purpose This study aims to evaluate the applicability of the endoscopy-assisted presigmoid retrolabyrinthine approach, advantages, disadvantages, and the applicability of surgery with pre-op radiological parameters; identify important landmarks; and to reveal their relationships with important structures in the surgical field with objective data. Also, we aim to improve the surgical technique for increasing reachable anatomic structure. Methods Mastoid drilling and endoscopy-assisted presigmoid retrolabyrinthine approach were performed and endoscopic instruments were used to obtain the three-dimensional pictures. Computed tomography images were evaluated to correlate to the anatomic data. Results In terms of pre-operative radiological evaluation of the applicability of the presigmoid approach were investigated with selected radiological parameters. The endoscopy-assisted presigmoid retrolabyrinthine approach applied to cadavers the relationship, distances between important anatomical landmarks, and anatomical structures in the surgical field recorded. The anatomical structures that could reach with the application of the procedure were recorded. The relationship between pre-operative measured radiological parameters and surgical results was evaluated with objective data. Additional combinations to improve this surgical method discussed and the results of our combination were recorded with photographs. Conclusion Although the presigmoid retrolabyrinthine approach has facilitated with the assistance of endoscope, it has observed that there are still some difficulties, and it has been concluded that the radiological parameters are useful in evaluating the applicability of this surgery. It observed that this surgery can be performed more effectively with combinations

A Novel Expression Profile of Cell Cycle and DNA Repair Proteins in Nonfunctioning Pituitary Adenomas

Tanriover, Necmettin/0000-0001-7628-9443; Kadioglu, Pinar/0000-0002-8329-140X; comunoglu, nil/0000-0002-2319-1757WOS: 000519375300002PubMed: 31828584The molecular mechanisms underlying the formation of nonfunctioning pituitary adenomas (NFAs) are largely unknown. in this study, we aimed to understand the relationship between NFAs and functional pituitary adenomas and the possible role of proteins involved in cell cycle, senescence, and DNA damage control mechanisms in the etiology of NFA. We analyzed pATM-S1981, pRb-S608, Rb, pE2F1-S364, p16, E2F1, p73, cyclin D1, and CHEK2 protein expression (in a group of 20 patients with acromegaly, 18 patients with Cushing's disease (CD), and 29 NFA patients) by immunohistochemistry and their relevant mRNA expression by qRT-PCR (in a group of 7 patients with acromegaly, 7 patients with CD, and 7 NFA patients). the clinical and histopathological results on the patients were statistically evaluated. pE2F1-S364 protein expression in the CD group was significantly lower than that in the NFA and acromegaly groups (p = 0.025, p = 0.034, respectively). However, the expression of the p16 protein was lower than in the NFA group than in the CD and acromegaly groups (p = 0.030, p = 0.033, respectively), and E2F1 protein expression was significantly higher in the NFA group than in the CD group (p = 0.025). p73 protein expression in patients with acromegaly was significantly higher (p = 0.031) than that in the CD group. CHEK2 mRNA expression in the CD group was significantly higher than that in the acromegaly group (p = 0.012). the selective and tumor-specific associations between E2F1, pE2F1-S364, CHEK2, and p73 mRNA and protein levels indicate their involvement in pituitary adenoma formation in NFA, CD, and acromegaly patients.Research Fund of the Istanbul UniversityIstanbul University [2017-25404] Funding Source: Medlin

A follow-up study on outcomes of endoscopic transsphenoidal approach for acromegaly

Objective: A thorough follow-up study in which the same clinic presents the change in the surgical outcomes of acromegaly over the years, is still lacking in the endoscopic era. In this study, we intended to evaluate the clinical characteristics, radiological features, surgical and late remission rates of newly diagnosed acromegaly patients treated in our clinic between 2014 and 2019 in order to delineate the surgical remission status according to radiological, microscopic, and hormonal features. As a follow-up to our initial report, we also aimed to display the change of surgical remission rates over time in a tertiary center