Pterion Prep CraniPro VUMC Case Prep
2026-06-27

Case Prep: Anterior Temporal Lobectomy / Selective Amygdalohippocampectomy (Epilepsy)

Case / Approach Snapshot

One-Liner

[Age]yo [M/F] with medically refractory [left/right] mesial temporal lobe epilepsy (hippocampal sclerosis) planned for [left/right] anterior temporal lobectomy with amygdalohippocampectomy.

Figures, Imaging & Video

🎥 Operative video — search operative video on YouTube ▸ · The Neurosurgical Atlas ▸

Neurosurgical Atlas · Radiopaedia · PubMed Central — operative figures © linked; see media-sources.md

High-Yield Literature

Curated Image Set

Open-access figures are embedded from PubMed Central articles and kept unique to this guide.

Anterior Temporal Lobectomy Selective Amygdalohippocampectomy — Figure 1 Figure 1. Schematic drawing of the typically noted position of the temporal horn. ©The Neurosurgical Atlas by Aaron A. Cohen-Gadol, MD, used with permission Source: External cortical landmarks and measurements for the temporal horn: Anatomic study with application to surgery of the temporal lobe — Surgical Neurology International 2015; CC BY-NC-SA.

Anterior Temporal Lobectomy Selective Amygdalohippocampectomy — Figure 2 Figure 2. Right-sided brain with pins in the anterior and posterior extent of the temporal horn Source: External cortical landmarks and measurements for the temporal horn: Anatomic study with application to surgery of the temporal lobe — Surgical Neurology International 2015; CC BY-NC-SA.

Anterior Temporal Lobectomy Selective Amygdalohippocampectomy — Figure 3 Figure 3. Left sided brain with pins marking the anterior and posterior extent of the temporal horn Source: External cortical landmarks and measurements for the temporal horn: Anatomic study with application to surgery of the temporal lobe — Surgical Neurology International 2015; CC BY-NC-SA.

Anterior Temporal Lobectomy Selective Amygdalohippocampectomy — Figure 1 Figure 1. Coronal view of temporal lobe Source: Seizure Outcome after Lesionectomy With or Without Concomitant Anteromedial Temporal Lobectomy for Low-Grade Gliomas of the Medial Temporal Lobe — Asian Journal of Neurosurgery 2021; CC BY-NC-SA.

Anterior Temporal Lobectomy Selective Amygdalohippocampectomy — Figure 2 Figure 2. Operative steps of AMTR. Incision on superior temporal sulcus between superior and middle temporal Gyrus [Figure 2a,b]; tumor infiltrating hippocampus [Figure 2c]. Gross total excision… Source: Seizure Outcome after Lesionectomy With or Without Concomitant Anteromedial Temporal Lobectomy for Low-Grade Gliomas of the Medial Temporal Lobe — Asian Journal of Neurosurgery 2021; CC BY-NC-SA.

Anterior Temporal Lobectomy Selective Amygdalohippocampectomy — Figure 3 Figure 3. Magnetic resonance imaging (a-c) and computed tomography (d) of ganglioneuroma operated by AMTR with gross total excision Source: Seizure Outcome after Lesionectomy With or Without Concomitant Anteromedial Temporal Lobectomy for Low-Grade Gliomas of the Medial Temporal Lobe — Asian Journal of Neurosurgery 2021; CC BY-NC-SA.

Anterior Temporal Lobectomy Selective Amygdalohippocampectomy — Figure 4 Figure 4. (a-e) Magnetic resonance imaging of a patient with medial temporal pilocytic astrocytoma operated by AMTR Source: Seizure Outcome after Lesionectomy With or Without Concomitant Anteromedial Temporal Lobectomy for Low-Grade Gliomas of the Medial Temporal Lobe — Asian Journal of Neurosurgery 2021; CC BY-NC-SA.

Anterior Temporal Lobectomy Selective Amygdalohippocampectomy — Figure 5 Figure 5. (a-c) The patient underwent AMTR. Histopathology showing mildly anisomorphic astrocytes around thin vascular spaces with microcystic degeneration (d). GFAP (Glial fibrillary acidic… Source: Seizure Outcome after Lesionectomy With or Without Concomitant Anteromedial Temporal Lobectomy for Low-Grade Gliomas of the Medial Temporal Lobe — Asian Journal of Neurosurgery 2021; CC BY-NC-SA.

Anterior Temporal Lobectomy Selective Amygdalohippocampectomy — Figure 1: Figure 1:. (a-d) Gliotic changes in the temporal lobe with complete hippocampal resection in patient no. 6. Source: One-year neuropsychological outcome after temporal lobe epilepsy surgery in large Czech sample: Search for factors contributing to memory decline — Surgical Neurology International 2022; CC BY-NC-SA.

Anterior Temporal Lobectomy Selective Amygdalohippocampectomy — Figure 2: Figure 2:. (a-d) Hippocampal remnants after the right-sided anteromesial temporal resection in patient no. 2. Source: One-year neuropsychological outcome after temporal lobe epilepsy surgery in large Czech sample: Search for factors contributing to memory decline — Surgical Neurology International 2022; CC BY-NC-SA.

History of Present Illness

Imaging Review

MRI (epilepsy protocol — thin coronal hippocampal cuts, FLAIR)

Functional

Labs

Neurological Examination

Surgical Planning

Case Logistics, OR Needs & Orders

Diagnosis & Indication

Position

Approach: Temporal Craniotomy

Key Surgical Steps (ATL)

  1. Question-mark/reverse-question-mark temporal incision, temporal craniotomy (low to middle fossa floor)
  2. Open dura, expose temporal lobe
  3. Lateral neocortical resection: measure from temporal tip — typically ~4-4.5 cm dominant, ~5-5.5 cm non-dominant along middle temporal gyrus (stay anterior to avoid Wernicke; limit superior temporal gyrus on dominant side)
  4. Subpial resection of superior/middle/inferior temporal gyri; enter the temporal horn of the lateral ventricle
  5. Identify ventricular landmarks: choroid plexus, choroidal fissure, hippocampus, collateral eminence
  6. Mesial resection: resect amygdala (anterior, up to level of choroidal point — avoid going superomedial into basal ganglia/optic tract), then hippocampus and parahippocampal gyrus
  7. Disconnect hippocampus posteriorly (en bloc or piecemeal), divide hippocampal/fimbrial attachments
  8. Preserve the pia over the medial structures protecting the brainstem, CN III, PCA, anterior choroidal artery, and basal vein in the ambient cistern
  9. Hemostasis, closure

Critical Anatomy & Structures at Risk

  1. Optic radiations / Meyer’s loop — superior/lateral resection → contralateral superior quadrantanopia (“pie in the sky”)
  2. Language cortex (dominant — Wernicke posterior, basal temporal language) — limit posterior/superior extent
  3. MCA branches (Sylvian), anterior choroidal & PCA, basal vein of Rosenthal (medial, ambient cistern)
  4. CN III, midbrain (medial — preserve pia)
  5. Memory (contralateral hippocampal reserve — Wada)

Equipment

Monitoring

Anesthesia

Potential Complications

  1. Visual field deficit (superior quadrantanopia — Meyer’s loop) — common, often subclinical
  2. Memory decline (dominant hippocampus — Wada predicts), naming difficulty (dominant)
  3. Vascular injury (anterior choroidal → hemiparesis; PCA, MCA)
  4. CN III palsy, hemiparesis, hemorrhage, infection
  5. Persistent seizures (~30% not seizure-free)

Operative Note Template

Preoperative Diagnosis: Drug-resistant [left/right] mesial temporal lobe epilepsy (hippocampal sclerosis)

Postoperative Diagnosis: Same

Procedure: [Left/Right] anterior temporal lobectomy with amygdalohippocampectomy

Surgeon / Assistant: Anesthesia: General endotracheal EBL / Fluids: Adjuncts: Neuronavigation, microscope, CUSA; [ECoG; awake mapping if dominant] Implants: None Complications: None

Indications: [Age]yo [M/F] with drug-resistant mesial temporal lobe epilepsy and concordant EEG/MRI (hippocampal sclerosis); Wada/fMRI established [language/memory] lateralization. Risks (visual field cut, memory/naming, vascular) discussed.

Description of Procedure: After consent and time-out, general anesthesia was induced and the head positioned (rotated ~60–90°). A temporal craniotomy low to the middle fossa floor was performed and the dura opened. A lateral neocortical resection was carried out along the middle temporal gyrus (~[4–4.5 cm dominant / 5–5.5 cm non-dominant] from the temporal tip), and the temporal horn entered, identifying the choroid plexus, hippocampus, and collateral eminence.

The amygdala was resected (up to the level of the choroidal point) and the hippocampus and parahippocampal gyrus removed. The pia over the medial structures was preserved, protecting the brainstem, CN III, PCA, anterior choroidal artery, and basal vein in the ambient cistern; vascular structures were preserved. [ECoG was used as indicated.]

Hemostasis was obtained, the dura closed, the bone replaced, and the scalp closed. The patient was awakened and transferred for postoperative visual-field assessment.

Postoperative Plan

Chief-Level Case Review

Use these as the senior-level mental model for Anterior Temporal Lobectomy / Selective Amygdalohippocampectomy (Epilepsy):

Common Pimp Questions

Use these to pressure-test preparation for Anterior Temporal Lobectomy / Selective Amygdalohippocampectomy (Epilepsy):

  1. What is the symptom target and what finding proves the correct neural structure is being treated?
  2. What imaging, tractography, MER, stimulation, or mapping information changes the trajectory?
  3. What medication adjustments or anesthesia constraints matter on the day of surgery?
  4. What complication would be subtle but important to detect in recovery?
  5. What postop programming, imaging, seizure, swallow, or cranial-nerve plan is needed?

Attending Preference Variables

Items that commonly vary by surgeon or institution: