MRCPsych Paper A1 Mock Examination 4: Answers
Melvyn WB Zhang, Cyrus SH Ho, Roger Ho, Ian H Treasaden, Basant K Puri in Get Through, 2016
Scotoma is defined as an area of reduced vision (e.g. central scotoma) and is commonly caused by demyelinating diseases such as multiple sclerosis or macular degeneration. Hemianopia is defined as loss of half of visual field of both eyes (either left side or right side). Damage to the right posterior portion of the brain usually causes a loss of the left half of visual fields in both eyes. Similarly, damage to the left posterior brain usually causes a loss of right half of visual fields in both eyes. Homonymous quadrantanopia is defined as loss of either outer upper or lower quadrant of visual field of one eye. For example, left superior homonymous quadrantanopia is caused by right temporal lobe lesion. Bitemporal hemianopia is defined as loss of outer half of visual fields in both eyes and is commonly caused by pituitary tumour.
Neuroanatomy
Helen Butler, Neel Sharma, Tiago Villanueva in Student Success in Anatomy - SBAs and EMQs, 2022
For each of the following scenarios described, select the most appropriate answer from the above list of options. Each option may be used once, more than once or not at all. Visual field examination demonstrating a superior quadrantanopia.A man presenting with ‘tunnel vision' and found on examination to have a bitemporal hemianopia.A 3 3 -year-old woman complaining of double vision. On examination she is unable to abduct her left eye.On shining a light into the right eye, the left pupil constricts, while the right does not.A 78-year-old man in the stroke unit with an inferior quadrantanopia.
The Problems
John Greene, Ian Bone in Understanding Neurology a problem-orientated approach, 2007
The optic tract continues posteriorly to the lateral geniculate body, where the axons synapse with cell bodies whose subsequent axons go on to form the optic radiation. These pass backwards, coursing deep through the parietal and temporal lobes. Because the arrangement of axons within the optic radiation continues to follow the distribution that originated in the optic nerve, the superior fibres (in the parietal lobe) contain information from the superior retinal ganglion cells, which comes from the lower half of the visual field. Hence parietal lobe lesions, rather than causing a full hemianopic defect, affect just the inferior quadrant of the homonymous half visual field (a homonymous inferior quadrantanopia). Similarly, temporal lobe lesions affect just the superior quadrant (a homonymous superior quadrantanopia). These patterns are depicted in 97b.
Glioblastoma evolving within 10 days following unremarkable computer tomography of the brain: a case report
Published in International Journal of Neuroscience, 2021
Nils Schröter, Niklas Lützen, Soroush Doostkam, Benjamin Berger
Ten days later, the patient presented to our department with persistent hemiparesis of the right side and quadrantanopia of the right lower quadrant. CT scan of the brain showed a hemorrhagic space-occupying lesion in the left thalamus without vascular abnormalities on CT angiography (Figure 1(b,c)). In order to neutralize apixaban efficacy 3000 IE prothrombin complex (PPSB) were given. MRI of the brain another six days later revealed a lesion with ring-shaped gadolinium enhancement with central necrotic and partly hemorrhagic areas (Figure 1(d,e)), but without diffusion restriction (not shown in Figure 1), suggesting a high-grade glioma rather than an abscess. However, histological examination of a stereotactic biopsy showed predominantly reactive gliotic CNS tissue, fibrin, fresh hemorrhages, necrotic material and regionally also macrophages and numerous granulocytes. Due to the necrosis and granulocytic infiltrates as well as the lack of tumor detection, the diagnosis of an abscess was made (Figure 2(a–f)). However, microbiological pathogens could not be detected. Furthermore, screening for infectious foci (transthoracic and transesophageal echocardiography, dental examination including panoramic X-ray, X-ray of the thorax, CT of paranasal sinuses) or predisposing immunodeficiency (differential blood count, HIV serology and immunoglobulin levels) was unremarkable. Under the assumption of a cerebral abscess an empiric antibiotic therapy with metronidazole and ceftriaxone was initiated.
Transnasal transsphenoidal pituitary surgery in a large tertiary hospital, a retrospective study
Published in Acta Chirurgica Belgica, 2023
Charlotte Nys, Georges Versyck, Eveleen Buelens, Koen Engelborghs, Erwin Cornips, Heddy Van Leeuwen-Wintjens, Hugo Vankelecom, Frank Weyns, Diederik Peuskens
Most presenting symptoms were visual deficits in 34 cases (32.4% of the entire population), followed by hormonal hypersecretion in 34 cases (32.4%), hormonal shortage in 8 cases (7.6%), cranial nerve deficits in 8 cases (7.6%), and 17 patients (16.2%) with pituitary apoplexy (Table 2). Visual field deficits consisted of bitemporal heteronymous hemianopia in 85.3%, bilateral quadrantanopia in 8.8%, central visual loss or hemianopia in 5.8%. Thirty-four patients had hormonal hypersecretion with an excess of prolactin (PRL; 32.3%), growth hormone (GH; 32.3%), adrenocorticotropic hormone (ACTH; 32.3%), or thyroid-stimulating hormone (TSH; 2.9%). Cranial nerve deficits (n = 8) encompassed the oculomotor nerve (62.5%), the abducens nerve (12.5%), or both nerves (25.0%) (Table 2).
Occipital lobe epilepsy was presented in a patient with intracerebral schwannoma: a case report and literature review
Published in International Journal of Neuroscience, 2019
Hirotomo Ten, Koji Adachi, Fumio Yamaguchi, Akira Matsuno, Akira Teramoto, Akio Morita
A 19-year-old man, with no significant past history and no stigmata or family history of neurofibromatosis, has suffered from intermittent blurred vision with scintillation in his right visual field for 10–30 s, followed by headache over his occipital region once in a month since 3 years ago. He had no convulsive seizures with consciousness impairment. Brain MRI performed in local hospital demonstrated brain tumor and then the patient was referred to our hospital for further evaluation and treatments. Upon admission, his consciousness was clear without limb paralysis or paresthesia. The physical examination showed incomplete right inferior quadrantanopia, which was confirmed by perimeter, but no other positive findings.
Related Knowledge Centers
- Optic Radiation
- Parietal Lobe
- Occipital Lobe
- Temporal Lobe
- Brain
- Lesion
- Anopsia
- Visual Field