Supplemental Content: The clinical details of ten patients with supratentorial CMs and utility of qualitative data from HDFT in their management.
Clinical Details (Table 1, Figures 1-6) Patient 1
A 33-year-old right-handed female with a 16 mm CM in the right periatrial WM presented with refractory headaches and left hemibody numbness. During surveillance, she had another episode of left hemibody numbness and hemorrhage within the CM. HDFT, consistent with presentation demonstrated partial disruption of the right AF and slight medial displacement of TPC (Figure 1). She underwent an image guided right temporoparietal craniotomy and lesionectomy using endoscopic port surgery (EPS) with symptomatic resolution
postoperatively. The trajectory through the non-dominant posterior superior temporal gyrus avoided the AF and TPC fibers, located posterosuperiorly and anteromedially to the lesion respectively.
Patient 2
A 50-year-old right-handed man with a 14 mm anterior left temporal CM presented with a 28-year history of refractory complex partial seizures and no preoperative deficits. A functional MRI (fMRI) showed left hemisphere dominance with Wernicke’s in the posterior left superior temporal gyrus region, remote from the CM. HDFT, consistent with the fMRI demonstrated cortical (temporal) terminations of the AF, as being remote from the CM.
The patient underwent an awake left temporal craniotomy for resection of the CM and
surrounding epileptogenic tissue, with cortical stimulation and had no deficit postoperatively.
Patient 3
A 53-year-old right-handed male with a left thalamic CM presented with right-sided
weakness, headache and dysarthria. He underwent Gamma Knife Surgery and gradually fully recovered. He represented with another hemorrhagic event 5 years later, with the lesion, now measuring 25 mm. Neurological examination demonstrated significant dysarthria; right sided upper motor neuron (UMN) facial weakness; grade 4+/5 strength in the upper and lower extremities; and hemibody anesthesia. He was managed conservatively and at follow-up, had not returned to his baseline with the neurological examination, as above. HDFT revealed a
displaced and partially disrupted left CST, descending anterolateral to the CM with
accompanying posteromedial displacement of the left TPC (Figure 2). In view of significant preservation and anterolateral location of the CST; its risk of injury during an operative procedure and patient’s neurological status, he was managed conservatively with planned surveillance.
Patient 4
A 25-year-old right-handed female presented to another institution with right facial and extremity numbness, paresthesia and hemiparesis related to a left thalamic CM, which had bled on multiple occasions. She underwent a frontal parasagittal craniotomy and right-sided interhemispheric transcallosal contralateral approach at another institution leading to initial worsening of her paresis, followed by gradual resolution to 70-80% of normal strength.
Four years postoperatively, during surveillance for residual CM, she had another clinically relevant hemorrhage. When referred to our institution five years later, she had another symptomatic recurrence with grade 4+/5 power on the right side with an ataxic gait;
significant dysmetria and lack of proprioception.
HDFT demonstrated complete disruption of the left TPC and CST, although with evidence of some of the premotor fibers continuing on towards cerebral peduncle, probably representing a case of neuroplasticity and possibly explaining her partially preserved motor function (Figure 3). In view of the patient’s young age, previous hemorrhages, surgery (image-guided EPS) was offered, who has currently opted for conservative management.
Patient 5
A 67-year-old right-handed female presented with medically refractory focal seizures attributable to a 13 mm CM (Figure 4) in the left pars orbitalis region and characterized by right upper and lower limb weakness. An fMRI showed frontal language areas posterior to the lesion, at pars triangularis and opercularis and ventral premotor cortex. HDFT
demonstrated the frontal origin of the AF as being posterior to the CM, consistent with the fMRI (Figure 4A-B). An image-guided left frontal craniotomy (anterior trans-sulcal approach) was used for complete lesionectomy, with particular attention to the posterior margin. Postoperatively she had no seizures at six-months follow-up.
Patient 6
A 22-year-old left-handed female presented with a 12-year history of medically refractory complex partial seizures (episodes of bad taste and/or vomiting, word finding difficulty) attributable to a 16 mm CM at superior left insula with surrounding hemosiderin. An fMRI demonstrated left hemisphere dominance with Broca's and Wernicke's in their anatomical location with no major activation along the posterior margin of the lesion. HDFT
demonstrated medial deformation of a small segment of the left SLF fibers with an unaffected CST. Anterior cortical terminations of the AF on HDFT were consistent with Broca’s on the fMRI. In view of her presentation and HDFT findings, she is pending an awake craniotomy involving a transsylvian-transinsular approach and language mapping.
Patient 7
A 66-year-old right-handed female presented with acute headache, difficulty with
pronouncing words (words getting 'twisted') and a 10 mm left parietal lobe hemorrhagic CM . The lesion over eight months, doubled in size with MR evidence of blood products. Due to the lesion's proximity to the sensory cortex and its potential effect on the AF, she underwent HDFT and an fMRI in preparation for surgery. HDFT demonstrated posterior displacement of the AF around the lesion with the lateral margin being free of these fibers; anteromedial displacement of the TPC and an unaffected CST (Figure 4C-D). The fMRI confirmed the left hemisphere to be language dominant with Broca's in the inferior frontal gyrus. She
underwent an image-guided left parietal craniotomy and an approach through the post-central sulcus for lesionectomy, using information from the HDFT. Resection of the gliotic plane was limited due to the fiber tracts' proximity. Postoperatively she had normal speech.
Patient 8
A 26-year-old right-handed woman presented with an eight-year history of a complicated migraine disorder and a 13 mm hemorrhagic CM (at least two documented episodes of bleeding on CT) within the right caudate head with mild mass effect. She had transient ischemic symptoms (dysphasia, anomia, left-sided weakness (arm>leg), and gait dysfunction) during migrainous episodes, resistant to prophylactic medications. There was no history of seizures. HDFT demonstrated medial displacement of the fibers of anterior limb of the internal capsule. In view of her age and presentation, she underwent an image-guided right frontal craniotomy and EPS for resection of the lesion. HDFT and the MRI were used
preoperatively to plan a trajectory through the superior frontal sulcus with a pre-coronal entry point. Postoperatively patient had no deficit with an MRI showing complete resection.
Patient 9
A 53-year-old man presented with repeated seizures and a CM in the left orbitofrontal region, in front of the caudate head and putamen and medial to anterior insular sulcus. The patient previously had two episodes of seizures and headaches, presumably related to the bleeding of the CM. Surgery was offered in view of repeated hemorrhagic episodes with seizures being controlled medically. Preoperative HDFT demonstrated partial disruption of the orbitofrontal segment of UF, where the lesion was anatomically located (Figure 5). Based on this
information, for the lesion's resection, subfrontal route was selected to take advantage of the already established fiber damage and to avoid new disruption (Figure 5).
Patient 10
A 21-year-old lady presented with an episode of severe vertigo and light-headedness.
Neurological examination was normal with an MR demonstrating a posterior right frontal 15 mm hemorrhagic CM in the subcortical WM beneath the motor cortex. After initial
conservative management patient had a second symptomatic episode, leading to surgical management. HDFT demonstrated the proximity of the lesion to the CST and AF with both being on the medial side (Figure 6). Perilesionally the AF was displaced supero-medially. An image-guided craniotomy was used for excision of the CM, via an approach through the central sulcus. In the immediate post-operative period, she was noted to have minimal left facial UMN weakness with normal speech.
