port May 30, 2025 / Uncategorized Report a question What’s wrong with this question? You cannot submit an empty report. Please add some details. 0% Ethics & Law 1 / 1 1) Question Neonate with brain death, temp- 36C. How to diagnose: a.failure of respiratory drive after disconnection from MV increased PCO2 to 8 KPa b.EEG c.corneal reflex d.motor reflex, painful stimulation e. cerebral duplex u/s The correct approach to diagnosing brain death in a neonate (especially with a temperature of 36°C, which is within the acceptable range for testing) involves clinical neurological examinations and apnea testing, while ancillary tests (like EEG or duplex ultrasound) may be used in specific cases but are not primary diagnostic criteria. Correct Answer: Failure of respiratory drive after disconnection from MV (mechanical ventilation), increased PCO₂ to ≥ 8 kPa (60 mmHg) Explanation: Brain death diagnosis in neonates requires strict clinical criteria, including: Prerequisites Normalized temperature (≥ 36°C, as in this case). Exclusion of hypotension, metabolic disturbances, or drug effects (e.g., sedatives). Clinical Examination (Essential) Absence of brainstem reflexes: c. Corneal reflex (absent in brain death) d. Motor response to painful stimulation (absent in brain death) Apnea test (Most critical): Disconnect from ventilator, allow PCO₂ to rise to ≥ 8 kPa (60 mmHg). No respiratory effort confirms failure of respiratory drive (a). Ancillary Tests (Not Primary, but Used if Clinical Exam Inconclusive) b. EEG (electrocerebral silence supports diagnosis, but not required if clinical exam is conclusive) e. Cerebral duplex ultrasound (may show absent flow, but less definitive than clinical exam) Why Other Options Are Incorrect? b. EEG – Not mandatory unless clinical testing is impossible (e.g., severe facial trauma). e. Cerebral duplex ultrasound – Helpful but not definitive for brain death diagnosis. c & d – These are part of brainstem reflex testing, but apnea testing (a) is required for final confirmation. Key Takeaway: Apnea testing (a) is mandatory for diagnosing brain death in neonates. Brainstem reflexes (c, d) must also be absent. Ancillary tests (b, e) are secondary and used only if clinical exams cannot be completed. Source: UK Guidelines (NICE) and American Academy of Pediatrics (AAP) protocols for neonatal brain death determination. Your score is Send feedback
Ophthalmology May 19, 2025 / Ophthalmology / TAS 0% 1 Ophthalmology Ophthalmology 1 / 1 Category: Ophthalmology Q. Visual field defect: Left upper quadrantanopia a.right lower optic tract b.left lower optic tract c.left lower optic radiation d.right lower optic radiation e.geniculate nucleus Visual Field Defect: Left Upper Quadrantanopia – Answer & Explanation Correct Answer: d. Right lower optic radiation (Meyer’s loop) Explanation: Left upper quadrantanopia (defect in the left upper visual field) indicates a lesion affecting fibers carrying information from the right inferior retina (which corresponds to the left upper visual field). The optic radiation (part of the visual pathway after the optic tract) has two parts: Upper fibers (Baum’s loop) → Carry superior retinal (lower visual field) info → Pass through parietal lobe. Lower fibers (Meyer’s loop) → Carry inferior retinal (upper visual field) info → Loop into the temporal lobe. A lesion in the right lower optic radiation (Meyer’s loop) causes a left upper quadrantanopia (“pie in the sky” defect). Why Not Other Options? a. Right lower optic tract → Would cause a left homonymous hemianopia (not quadrantanopia). b. Left lower optic tract → Would cause a right homonymous hemianopia. c. Left lower optic radiation → Would cause a right upper quadrantanopia. e. Geniculate nucleus → Typically causes a homonymous hemianopia, sometimes with sparing of the temporal crescent. Key Points: Optic radiation lesions → Quadrantanopia (Meyer’s loop for upper, Baum’s loop for lower). Optic tract/LGN lesions → Complete homonymous hemianopia. Meyer’s loop (temporal) → “Pie in the sky” (upper quadrant defect). Baum’s loop (parietal) → “Pie on the floor” (lower quadrant defect). Mnemonic: “Meyer’s Loop goes to the Temporal lobe, causing a defect in the sky.” “Parietal (Baum’s) lesions knock the vision down to the floor.” Exam Tip: If a question gives quadrantanopia, think optic radiation (not tract/LGN). Upper field defect? → Temporal lobe (Meyer’s loop). Lower field defect? → Parietal lobe (Baum’s loop). Summary Table Lesion Location Visual Field Defect Right Meyer’s loop Left upper quadrantanopia Right Baum’s loop Left lower quadrantanopia Right optic tract/LGN Left homonymous hemianopia Optic chiasm Bitemporal hemianopia Your score is TAS
Recall TAS: Ophthalmology May 19, 2025 / Ophthalmology / TAS Q. Visual field defect: Left upper quadrantanopia a.right lower optic tract b.left lower optic tract c.left lower optic radiation d.right lower optic radiation e.geniculate nucleus TAS