We present the anatomical distribution of cerebral ischemic infarctions on MR imaging. In addition to T1W and T2W sequences, FLAIR and diffusion weighted images are utilized to diagnose infarction and various territorial territories.

Case 1: Anterior cerebral artery infarction. A 52 years old man presented with acute onset of right lower limb weakness. T2W and DWI images shows zonal delineation of the left anterior cerebral artery territory involving the interhemispheric parasagittal cortex of the frontal lobe. It is calssically involving the anterior two-thirds of the medial cerebral hemisphere and area over the cerebral convexity. 

Fig. 1: (A) Axial T2W (B) Axial DWI shows diffusion restricted infarction involving the left paramedian fronto-parietal cerebral cortex corresponding to the territory of the left anterior cerebral artery.

Case 2: An adult female with memory loss, irritability and behaviourial issues. MRI brain shows a chronic ischemic infarction involving the right frontal lobe. It is appearing low on DWI with normalization on ADC images. It is additionally associated with encephalomalacic and giotic changes. Findings corresponds to the territory of right anterior cerebral artery.

Fig. 2: (A) Axial T2W, (B) Coronal FLAIR, (C) Axial DWI and (D) Axial ADC shows chronic infarction in the right frontal lobe involving the territory of right anterior cerebral artery associated with gliotic and encephalomalacic changes.

Case 3: An uncoscious middle age adult was brought to the emergency room. His MRI shows linear confluent band-like abnormal signals parallel to the lateral ventricles in the centrum semiovale on the right side. Area of involvement corresponds to the deep borderzone area of ACA-MCA and MCA-PCA territories. 

Fig. 3: (A) Axial T2W (B) Axial DWI shows diffusion restricted infarction involving the right fronto-parietal and parietal cortex. Area of involvement corresponds to the deep borderzone and the cortical borderzone area of ACA-MCA and MCA-PCA territories.

Case 4: A 42 year old male patient presented with left hemiplagia. MRI brain shows diffusion restricted infarction involving the entire right basal ganglia.  Findings correspond to the territory of the medial and lateral lenticulostriate branches of the right ACA and MCA.

Fig. 4: (A) Axial T2W (B) Coronal T2W (C) Axial DWI and (A) Axial ADC shows acute infarction involving the putamen and head and body of the right caudate nucleus. There is also involvement of the posterior limb of internal capsule. Findings correspond to the territory of the medial and lateral lenticulostriate branches of the ACA and MCA.

Case 5:  A 50 year old female patient presented with altered level of consciousness with acute right hemiplagia. MRI brain shows diffusion restricted infarction involving the left basal ganglia.  Findings correspond to the territory of the medial and lateral lenticulostriate branches of the left ACA and MCA.

Fig. 5: (A) Axial T2W (B) Axial DWI shows acute infarction involving the head and body of caudate nucleaus and putamen of the left basal ganglia corresponding to the territory of the lateral and medial lenticulostriate branches of the ACA and MCA.

Case 6: A middle aged female presented with right sided hemiparesis. MR brain shows diffusion restricted infarction involving the left frontal lobe anterior to the sylvian fissure. Area of involvement corresponds to the territory of superior division of the left middle cerebral artery.

Fig. 6: (A,B) Axial T2W MR brain shows infarction involving left frontal lobe anterior to the sylvian fissure. Area of involvement corresponds to the territory of the superior division of the left middle cerebral artery.

Case 7: A middle aged male patient presented with acute right sided hemiplagia. MR shows large area of diffusion resticted infarction involving the left fornto-parieto-temporal lobe. Basal ganglia appears spared. Findings corresponds to the territory of the superior and inferior divisions of the left middle cerebral artery.

Fig. 7: (A) Axial T2W (B) Coronal T2W (C) Axial DWI and (D) Axial ADC shows large area of infarction involving the left perisylvian cerebral cortex and the insular cortex. Basal ganglia appears spared. Findings correspond to the territory of the superior and inferior divisions of the left middle cerebral artery.

Case 8:  A 48 years old male patient presented with acute left sided hemiplagia and hemisensory loss. MR shows large area of diffusion resticted infarction involving the right forntoparietal lobe and basal ganglia. Findings corresponds to the territory of the superior and inferior divisions of the left middle cerebral artery with involvement of the lenticulostriate branches as well.

Fig. 8: (A) Axial T2W (B) Axial DWI shows a large area of infarction involving the left perisylvian cerebral cortex, adjacent insular cortex, head of caudate and putamen of the left basal ganglia. Findings represent infarction involving the territory of the left MCA proximal main stem (superior division, inferior division and lenticulostriate branches).

Case 9:  A 40-year old male patient presented with aphasia.  MRI brain shows infarction of the left antero-inferior temporal lobe corresponding to the territory of the inferior division of the left middle cerebral artery.

Fig. 9: (A) Axial T2W and (B) Axial DWI shows infarction of the left antero-inferior temporal lobe corresponding to the territory of the inferior division of the left middle cerebral artery.

Case 10: A 51-years old female patient presented with acute right dense hemiplagia. MRI shows area of diffusion restricted infarction involving the left perisylvian cerebral cortex and adjacent insular cortex with involvement of the head of caudate and putamen of the basal ganglia. Findings correspond to the territory of the deep cortical branches, deep penetrating branches and the lenticulostraite branches of left MCA.

Fig. 10: (A) Axial T2W (B) Axial DWI (C) Coronal T2W shows a diffusion restricted area of infarction involving the left perisylvian cerebral cortex, adjacent insular cortex. In addition there is involvement of the head of caudate and putamen of the left basal ganglia. Findings correspond to the territory of the deep cortical branches, deep penetrating branches and the lenticulostraite branches of left MCA.

Case 11: A 65 years old diabetic female presented with visual agnosia. Her MRI brain shows a cortical based area of acute infarction involving the left occipital lobe corresponding to the territory of the left posterior cerebral artery. 

Fig. 11: (A) Axial (B) Axial DWI shows a wedge-shaped cortical based area of infarction involving the left occipital lobe corresponding to the territory of the left posterior cerebral artery.

Case 12: 

A 49 years old athlete presented with contralateral hemianopsia and hemisensory loss. MRI shows diffusion restricted infarction involving the right thalamus, right medial occipital and medial temporal lobes. Area of involvement corresponds to the territory of the right proximal posterior cerebral artery. 

Fig. 12: (A) Axial T2W, (B) Coronal FLAIR, (C) Axial DWI shows diffusion restricted infarction involving the right thalamus, right medial occipital and medial temporal lobes. Area of involvement corresponds to the territory of the right proximal posterior cerebral artery. (D) MRA image shows occlusion of the right PCA.

Case 13:  A 50 years old male hypertensive patient presented with acute cortical blindness. His MRI shows cortical based infarction involving parasagittal left occipital lobe corresponding to the territory of the left posterior cerebral artery. 

Fig. 13: (A) Axial (B) Axial DWI shows an area of cortical based infarction involving parasagittal left occipital lobe corresponding to the territory of the left posterior cerebral artery.

Case 13: A 70-years old female presented with dizziness, headaches, nausea and vomiting not responding to the usual medical managament. Her MR brain shows an wedge-shaped infarction involving the caudal portion of the left cerebellar hemisphere corresponding to the territory of right posterior inferior cerebellar artery (PICA).

Fig. 14: (A) Axial T2W and (B) Axial DWI and (C) Coronal T2W MR brain shows an area of infarction involving the caudal portion of the left cerebellar hemisphere corresponding to the territory of right posterior inferior cerebellar artery (PICA).

Case 14:  A 77 years old male patient presented with dizziness, diplopia, multidirectional nystagmus and unsteady gait. MR brain shows infarction involving the right lateral medulla as well as the posterior inferior aspect of the right cerebellum corresponding to the territory of right posterior inferior cerebellar artery.

Fig. 15: (A) Axial T2W and (B) Axial DWI MRI brain shows infarction involving the right cerebellar hemisphere and lateral medulla corresponding to the territory of right posterior inferior cerebellar artery.

Case 15: An old age patient presented with vertigo, nausea, and truncal ataxia. MR shows infarction involving the inferior cerebellum and inferior cerebellar vermis corresponding to the territory of left posterior inferior cerebellar artery (PICA). Small area of infarction was also seen in the contralateral cerebellum. 

Fig. 16: (A) Axial T2W (B) Coronal T2W (C) Axial DWI and (D) Axial ADC shows an area of infarction involving the inferior cerebellum, inferior cerebellar vermis and lateral medulla corresponding to the territory of left posterior inferior cerebellar artery (PICA). Small area of infarction was also seen in the contralateral cerebellum.