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Ahmed Shafik - One of the best experts on this subject based on the ideXlab platform.

  • Electrophysiologic Activity of the Tunica Albuginea and Corpora Cavernosa: Possible Role of Tunica Albuginea in the Erectile Mechanism
    The journal of sexual medicine, 2007
    Co-Authors: Ahmed Shafik, Olfat El Sibai
    Abstract:

    ABSTRACT Introduction It is claimed that the tunica albuginea (TA) shares in the erectile mechanism by compressing the Emissary Veins passing through it. However, the TA does not contain smooth muscle fibers. Aim We investigated the hypothesis that TA lacks a contractile activity on the Emissary Veins passing through it. Methods Fourteen healthy male volunteers (mean age 35.2 ± 4.3 years) were studied. The electromyographic (EMG) activity of the TA and corpora cavernosa (CC) was individually recorded in the flaccid and erectile phases by EMG needle electrodes. Recording was performed in the upper, middle, and lower third of the TA and CC on one and then on the contralateral side. Main Outcome Measures The TA lacks a contractile activity on the Emissary Veins passing through it. Results The EMG of the CC in the flaccid phase recorded regular slow waves and random action potentials. The wave variables in the erectile phase exhibited a significant decrease ( P Conclusions Electric waves were recorded from the CC in the flaccid phase; wave variables decreased at erection. In contrast, the TA showed no electric waves in the flaccid or erectile phases. It appears that the TA acts as a CC covering sheet which expands passively at erection, and shares in compressing the subtunical venular plexus between it and the tumescent CC. Shafik A, Shafik AI, El Sibai O, and Shafik AA. Electrophysiologic activity of the tunica albuginea and corpora cavernosa: Possible role of tunica albuginea in the erectile mechanism.

Santi Maria Recupero - One of the best experts on this subject based on the ideXlab platform.

  • Review Article Ophthalmic Alterations in the Sturge-Weber Syndrome, Klippel-Trenaunay Syndrome, and the Phakomatosis Pigmentovascularis: An Independent Group of Conditions?
    2016
    Co-Authors: Maria Teresa Contestabile, Santi Maria Recupero
    Abstract:

    Copyright © 2015 Solmaz Abdolrahimzadeh et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. The phakomatoses have been traditionally defined as a group of hereditary diseases with variable expressivity characterized by multisystem tumors with possible malignant transformation. The Sturge-Weber syndrome, Klippel-Trenaunay syndrome, and the phakomatosis pigmentovascularis have the facial port-wine stain in common. Numerous pathophysiogenetic mechanisms have been suggested such as venous dysplasia of the Emissary Veins in the intracranial circulation, neural crest alterations leading to alterations of autonomic perivascular nerves, mutation of the GNAO gene in the Sturge-Weber syndrome, PIK3CA mutation in malformative/overgrowth syndromes such as the Klippel-Trenaunay syndrome, and the twin-spotting phenomenon in phakomatosis pigmentovascularis. Other features linked to the port-wine stain and typical to all of the three conditions are glaucoma and choroidal alterations. Glaucoma can be due to malformations of the anterior chamber or high episcleral venous pressure and in phakomatosis pigmentovascularis it can also be associated with angle hyperpigmentation. The choroid can be thickened in all diseases. Furthermore, choroidal melanocytosis in the phakomatosis pigmentovascularis can lead to malignan

  • Ophthalmic Alterations in the Sturge-Weber Syndrome, Klippel-Trenaunay Syndrome, and the Phakomatosis Pigmentovascularis: An Independent Group of Conditions?
    Hindawi Limited, 2015
    Co-Authors: Solmaz Abdolrahimzadeh, Vittorio Scavella, Lorenzo Felli, Filippo Cruciani, Maria Teresa Contestabile, Santi Maria Recupero
    Abstract:

    The phakomatoses have been traditionally defined as a group of hereditary diseases with variable expressivity characterized by multisystem tumors with possible malignant transformation. The Sturge-Weber syndrome, Klippel-Trenaunay syndrome, and the phakomatosis pigmentovascularis have the facial port-wine stain in common. Numerous pathophysiogenetic mechanisms have been suggested such as venous dysplasia of the Emissary Veins in the intracranial circulation, neural crest alterations leading to alterations of autonomic perivascular nerves, mutation of the GNAO gene in the Sturge-Weber syndrome, PIK3CA mutation in malformative/overgrowth syndromes such as the Klippel-Trenaunay syndrome, and the twin-spotting phenomenon in phakomatosis pigmentovascularis. Other features linked to the port-wine stain and typical to all of the three conditions are glaucoma and choroidal alterations. Glaucoma can be due to malformations of the anterior chamber or high episcleral venous pressure and in phakomatosis pigmentovascularis it can also be associated with angle hyperpigmentation. The choroid can be thickened in all diseases. Furthermore, choroidal melanocytosis in the phakomatosis pigmentovascularis can lead to malignant transformation. Although the multiple pathophysiological mechanisms still require clarification, similarities in ophthalmic manifestations make it reasonable to classify these diseases in an independent group

José M. Valdueza - One of the best experts on this subject based on the ideXlab platform.

  • Diagnostic Pitfall: Atypical Cerebral Venous Drainage via the Vertebral Venous System
    2014
    Co-Authors: Olaf Hoffmann, Johann S. Braun, Juri Katchanov, Olf Klingebiel, José M. Valdueza
    Abstract:

    Summary: We report a case of atypical cerebral venous drainage in a 38-year-old woman with symptoms of benign paroxysmal positional vertigo. Thrombosis of the left inter-nal jugular vein and sigmoid sinus was suspected on the basis of spin-echo and time-of-flight MR findings, but mul-tisection CT angiograms showed a patent sigmoid sinus and predominant drainage via the Emissary Veins toward the vertebral plexus, with only a minor contribution of the jugular Veins. This case illustrates the variability of the venous anatomy in the craniocervical region. Internal jugular vein (IJV) and sigmoid sinus thrombosis was suspected because of the following: 1) absence of flow-induced signal alterations on MR images, 2) apparent collateral flow through strongly dilated intraspinal and vertebral Veins, and 3) lo

  • Diagnostic pitfall: atypical cerebral venous drainage via the vertebral venous system.
    AJNR. American journal of neuroradiology, 2002
    Co-Authors: Olaf Hoffmann, Randolf Klingebiel, Johann S. Braun, Juri Katchanov, José M. Valdueza
    Abstract:

    We report a case of atypical cerebral venous drainage in a 38-year-old woman with symptoms of benign paroxysmal positional vertigo. Thrombosis of the left internal jugular vein and sigmoid sinus was suspected on the basis of spin-echo and time-of-flight MR findings, but multisection CT angiograms showed a patent sigmoid sinus and predominant drainage via the Emissary Veins toward the vertebral plexus, with only a minor contribution of the jugular Veins. This case illustrates the variability of the venous anatomy in the craniocervical region.

Muhammet Arslan - One of the best experts on this subject based on the ideXlab platform.

  • Emissary Veins prevalence and evaluation of the relationship between dural venous sinus anatomic variations with posterior fossa Emissary Veins: MR study
    La radiologia medica, 2019
    Co-Authors: Pinar Gulmez Cakmak, Furkan Ufuk, Ahmet Baki Yagci, Ergin Sagtas, Muhammet Arslan
    Abstract:

    Purpose The aim of this study was to find the prevalence of Emissary Veins and to compare the visibility of these Emissary Veins with the anatomic variations of the dural venous sinuses detected in magnetic resonance venography (MRV). Materials and methods All MR images of two hundred twenty patients were evaluated retrospectively. Posterior cranial fossa Emissary Veins diameter measurements were performed in the axial plane. The anatomic variations of the venous sinuses in MRVs of all patients were recorded. Accordingly, the presence of the Emissary Veins was compared with the dural venous sinus anatomic variations. p  

  • Emissary Veins prevalence and evaluation of the relationship between dural venous sinus anatomic variations with posterior fossa Emissary Veins: MR study
    La Radiologia medica, 2019
    Co-Authors: Pinar Cakmak, Furkan Ufuk, Ahmet Baki Yagci, Ergin Sagtas, Muhammet Arslan
    Abstract:

    The aim of this study was to find the prevalence of Emissary Veins and to compare the visibility of these Emissary Veins with the anatomic variations of the dural venous sinuses detected in magnetic resonance venography (MRV). All MR images of two hundred twenty patients were evaluated retrospectively. Posterior cranial fossa Emissary Veins diameter measurements were performed in the axial plane. The anatomic variations of the venous sinuses in MRVs of all patients were recorded. Accordingly, the presence of the Emissary Veins was compared with the dural venous sinus anatomic variations. p 

  • Emissary Veins prevalence and evaluation of the relationship between dural venous sinus anatomic variations with posterior fossa Emissary Veins mr study
    Radiologia Medica, 2019
    Co-Authors: Pinar Cakmak, Furkan Ufuk, Ahmet Baki Yagci, Ergin Sagtas, Muhammet Arslan
    Abstract:

    The aim of this study was to find the prevalence of Emissary Veins and to compare the visibility of these Emissary Veins with the anatomic variations of the dural venous sinuses detected in magnetic resonance venography (MRV). All MR images of two hundred twenty patients were evaluated retrospectively. Posterior cranial fossa Emissary Veins diameter measurements were performed in the axial plane. The anatomic variations of the venous sinuses in MRVs of all patients were recorded. Accordingly, the presence of the Emissary Veins was compared with the dural venous sinus anatomic variations. p < 0.05 was considered statistically significant. An inter-observer reliability analysis was performed. The prevalence of Emissary Veins in MRI was found in the right mastoid Emissary vein (MEV) 82.7% and left MEV 81.4%. Occipital Emissary vein (OEV) was present in 63 patients (28.6%) for the first radiologist (R1), and it was present in 61 patients (27.7%) for the second radiologist (R2) (K = 0.978). A statistically significant correlation was detected between the diameter of the left MEV and gender (p < 0.05) for both radiologists. There was a statistically significant difference between the left MEV and OEV and transverse sinus anatomic variations. MR imaging is a noninvasive and irradiating imaging method for detecting posterior fossa major Emissary Veins, and we recommend using MR imaging for preoperative evaluation of posterior fossa major Emissary Veins and related dural venous sinuses.

Arslan M. - One of the best experts on this subject based on the ideXlab platform.

  • Emissary Veins prevalence and evaluation of the relationship between dural venous sinus anatomic variations with posterior fossa Emissary Veins: MR study
    'Springer Science and Business Media LLC', 2019
    Co-Authors: Gulmez Cakmak P., Ufuk F., Yagci A.b., Sagtas E., Arslan M.
    Abstract:

    Purpose: The aim of this study was to find the prevalence of Emissary Veins and to compare the visibility of these Emissary Veins with the anatomic variations of the dural venous sinuses detected in magnetic resonance venography (MRV). Materials and methods: All MR images of two hundred twenty patients were evaluated retrospectively. Posterior cranial fossa Emissary Veins diameter measurements were performed in the axial plane. The anatomic variations of the venous sinuses in MRVs of all patients were recorded. Accordingly, the presence of the Emissary Veins was compared with the dural venous sinus anatomic variations. p < 0.05 was considered statistically significant. An inter-observer reliability analysis was performed. Results: The prevalence of Emissary Veins in MRI was found in the right mastoid Emissary vein (MEV) 82.7% and left MEV 81.4%. Occipital Emissary vein (OEV) was present in 63 patients (28.6%) for the first radiologist (R1), and it was present in 61 patients (27.7%) for the second radiologist (R2) (K = 0.978). A statistically significant correlation was detected between the diameter of the left MEV and gender (p < 0.05) for both radiologists. There was a statistically significant difference between the left MEV and OEV and transverse sinus anatomic variations. Conclusion: MR imaging is a noninvasive and irradiating imaging method for detecting posterior fossa major Emissary Veins, and we recommend using MR imaging for preoperative evaluation of posterior fossa major Emissary Veins and related dural venous sinuses. © 2019, Italian Society of Medical Radiology

  • Emissary Veins prevalence and evaluation of the relationship between dural venous sinus anatomic variations with posterior fossa Emissary Veins: MR study.
    'Springer Science and Business Media LLC', 2019
    Co-Authors: Gulmez Cakmak Pauid- Orcid: 0000-0003-4652-6748, Ufuk F., Sagtas E., Arslan M.
    Abstract:

    PURPOSE: The aim of this study was to find the prevalence of Emissary Veins and to compare the visibility of these Emissary Veins with the anatomic variations of the dural venous sinuses detected in magnetic resonance venography (MRV). MATERIALS AND METHODS: All MR images of two hundred twenty patients were evaluated retrospectively. Posterior cranial fossa Emissary Veins diameter measurements were performed in the axial plane. The anatomic variations of the venous sinuses in MRVs of all patients were recorded. Accordingly, the presence of the Emissary Veins was compared with the dural venous sinus anatomic variations. p < 0.05 was considered statistically significant. An inter-observer reliability analysis was performed. RESULTS: The prevalence of Emissary Veins in MRI was found in the right mastoid Emissary vein (MEV) 82.7% and left MEV 81.4%. Occipital Emissary vein (OEV) was present in 63 patients (28.6%) for the first radiologist (R1), and it was present in 61 patients (27.7%) for the second radiologist (R2) (K = 0.978). A statistically significant correlation was detected between the diameter of the left MEV and gender (p < 0.05) for both radiologists. There was a statistically significant difference between the left MEV and OEV and transverse sinus anatomic variations. CONCLUSION: MR imaging is a noninvasive and irradiating imaging method for detecting posterior fossa major Emissary Veins, and we recommend using MR imaging for preoperative evaluation of posterior fossa major Emissary Veins and related dural venous sinuses

  • Veins: MR study
    'Springer Science and Business Media LLC', 2019
    Co-Authors: Pg Cakmak, Ufuk F., Sagtas E., Ab Yagci, Arslan M.
    Abstract:

    PurposeThe aim of this study was to find the prevalence of Emissary Veins and to compare the visibility of these Emissary Veins with the anatomic variations of the dural venous sinuses detected in magnetic resonance venography (MRV).Materials and methodsAll MR images of two hundred twenty patients were evaluated retrospectively. Posterior cranial fossa Emissary Veins diameter measurements were performed in the axial plane. The anatomic variations of the venous sinuses in MRVs of all patients were recorded. Accordingly, the presence of the Emissary Veins was compared with the dural venous sinus anatomic variations. p