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Write short notes on the early development of the vitreous
Published in Nathaniel Knox Cartwright, Petros Carvounis, Short Answer Questions for the MRCOphth Part 1, 2018
Nathaniel Knox Cartwright, Petros Carvounis
Between weeks 4 and 5 the lentoretinal space becomes filled with fibrils, mesenchymal cells and vascular channels. These elements constitute the primary vitreous. The mesenchymal cells and vascular channels derive from the hyaloid artery, which enters the optic cup through the choroidal fissure. The hyaloid artery gives rise to a series of small capillaries that anastomose with choroidal and long ciliary arteries to form a vascular capsule, the tunica vasculosa lentis, providing the rich nutrient supply necessary for the rapid growth of the lens during development.
Test Paper 7
Published in Teck Yew Chin, Susan Cheng Shelmerdine, Akash Ganguly, Chinedum Anosike, Get Through, 2017
Teck Yew Chin, Susan Cheng Shelmerdine, Akash Ganguly, Chinedum Anosike
Mesial temporal sclerosis typically demonstrates an atrophic, T2 hyperintense hippocampus on imaging. Other pathology affecting the temporal lobe including infection and tumour would cause enlargement of the hippocampus. Alzeheimer’s dementia results in medial temporal atrophy, but T2-weighted hyperintensity is not a feature. Herpes encephalitis is caused by Herpes simplex virus (HSV) type 1 in adults and HSV type II in children. It involves the limbic lobe (hypothalamus, parahippocampal gyrus, cingulate gyrus); and typically appears bilateral but asymmetric. Gyriform enhancement and haemorrhage are late features. Choroidal fissure cyst is a benign incidental finding, similar to arachnoid cysts in the brain. These occur in the region of the hippocampal fissure.
The viva: operative surgery and surgical anatomy
Published in Vivian A. Elwell, Ramez Kirollos, Syed Al-Haddad, Neurosurgery, 2014
Vivian A. Elwell, Ramez Kirollos, Syed Al-Haddad
Foraminal entry via the foramen of Monro, especially if it has been dilated by the presence of hydrocephalus, is the least traumatic. The choroidal fissure can be opened posteriorly to enlarge the foramen of Monro.
Transcortical transventricular transchoroidal-fissure approach to distal fusiform hyperplastic anterior choroidal artery aneurysms
Published in British Journal of Neurosurgery, 2023
Caleb Rutledge, Soren Jonzzon, Ethan Andrew Winkler, Steven William Hetts, Adib Adnan Abla
In this case, the proximal aneurysm was in the anterior ambient cistern, however the more distal aneurysm was in the posterior aspect of the cistern and was located superiorly in relation to the first aneurysm, adjacent to the tail of the hippocampus. We elected to perform a transcortical transventricular transchoroidal-fissure approach. This lateral approach requires less temporal lobe traction and allows for early proximal control, however places both the optic pathway (optic tract, Meyer’s loop, and lateral geniculate nucleus) and speech areas in the dominant hemisphere at risk. To minimize these risks, we made a limited corticectomy in the middle temporal gyrus and approached the aneurysm from the anterior temporal lobe. As illustrated, opening the choroidal fissure and retracting the hippocampus inferiorly exposes the whole of the ambient cistern (Figure 7).
Supratentorial hemangioblastomas in von Hippel–Lindau wild-type patients – case series and literature review
Published in International Journal of Neuroscience, 2018
Luís Rocha, Carolina Noronha, Ricardo Taipa, Joaquim Reis, Mário Gomes, Ernesto Carvalho
A large review and characterization of tumour location was made by Mills et al. [3] in 2012, which encompassed 131 patients with 147 lesions. From those, 85 tumours (58%) were found in frontal, parietal or temporal lobes, in decreasing order. Thirty-eight cases (26%) were found in the sellar/suprasellar region, 15 cases (10%) were intraventricular and 9 cases (6%) in other locations. Studies by Lonser [50] and Peyre [12] demonstrate that pituitary stalk HBL appears to be one of the most frequent locations, around 10%–20%. In the literature, 86.8% of the HBL were intraparenchymal, 6.6% intraventricular and 5.6% with meningeal implantation [1,24,51]. Some rare cases affect the choroidal fissure [33].
Ophthalmologic and facial abnormalities of Nicolaides-Baraitser syndrome
Published in Ophthalmic Genetics, 2022
Russell Simmers, Allison Goodwin, Hind Al Saif, Natario Couser
A head MRI performed at 2 years old found small bilateral choroidal fissure cysts, generalized prominence of the perivascular spaces, and symmetric faint T2 signal hyperintensity and restricted diffusion along the anticipated courses of the central segmental tracts. With drug therapy, the patient’s last reported seizure was nearly 2 years before the most recent patient encounter.