Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma

Abstract

Chronic subdural hematoma (cSDH) is predicted to become the most common neurosurgical pathology by 2030. Surgical evacuation is a critical component of cSDH management, and postoperative monitoring is important given high recurrence rates and concerns related to restarting anticoagulation. Given issues related to cost, radiation exposure, and time for computerized tomography (CT) and magnetic resonance imaging examinations, we developed a novel technique to detect, assess, and quantify residual and/or recurrent subdural hematoma with point-of-care, hand-held ultrasound and sonolucent burr-hole covers placed during the initial surgery. We prospectively collected and retrospectively analyzed clinical and radiographical data for cSDH patients treated with burr-hole evacuation and implanted sonolucent burr-hole covers. Postoperative outpatient follow-up included direct comparison of point-of-care ultrasound (US) and head CT as the gold standard. Implant-to-cortical distance and absolute hematoma thickness were measured using ImageJ and Unity PACS on follow-up scans. Nine patients underwent burr-hole evacuation of cSDH with placement of a sonolucent cover. Hematoma thickness and cover-to-septum pellucidum distance did not differ between the two techniques. Both US and CT detected recurrent subdural hematoma in one of the nine patients. US and CT showed resolution of cSDH for the remaining seven subjects at follow-up, demonstrating 100% concordance between the US and CT methods. No immediate or short-term complications and infections related to the use of the sonolucent cover were noted in this cohort. Ultrasound-based assessment using a sonolucent burr-hole cover showed good concordance with CT for detecting and ruling out recurrent cSDH in a small cohort of patients. Point-of-care US could become a supplemental imaging modality for postoperative evaluation of cSDH.

Keywords

chronic subdural hematoma burr-hole evacuation postoperative follow-up sonolucent covers postoperative ultrasound

Introduction

Chronic subdural hematoma (cSDH) is a common neurosurgical disease characterized by the accumulation of blood products and subdural membranes in the subdural space.¹ While its overall incidence is currently reported between 2 and 20 cases per 100,000 people, cSDH is on track to become the most common neurosurgical diagnosis by the year 2030.² Historically, cSDH has been associated with traumatic brain injury (TBI),³ but more recent evidence suggests additional pathophysiological mechanisms underlying this disease.⁴ Importantly, cSDH is linked to excess mortality that can persist up to 20 years after diagnosis.^5,6

Surgical treatment has been the mainstay of cSDH care. In the last several years, surgical evacuation has increasingly been combined with pre- or postoperative middle meningeal artery embolization (MMAE). Stand-alone cSDH evacuation via burr hole or twist-drill drainage is associated with recurrence rates comprised of 3–33%.^7–10 The addition of MMAE has lowered the 90-day cSDH recurrence rate (EMBOLISE),¹¹ as well as treatment failure at 180 days (STEM and MEMBRANE trials). Despite this, cSDH recurrence/progression, need for additional surgery, and major neurological deficits still occur in 4–16% of patients after maximal treatment.^12,13

Postoperative cSDH evacuation outcomes are routinely surveilled via computerized head tomography (CT) or magnetic resonance imaging (MRI) of the head.¹⁴ The high resolution offered by these techniques comes at a cost. CT is associated with radiation exposure, and both MRI and CT carry high monetary costs and can impose logistical complexity during postoperative follow-up. With improving ultrasound (US) resolution and availability, the use of sonolucent cranial implants has gained traction for surveillance of bypass, hydrocephalus, Chiari, post-traumatic, and cSDH patients.^15–18 Importantly, it could constitute a valuable addition to postoperative and outpatient follow-up by providing rapid assessment for recurrent hematoma.

Here we present a small single-institution series of cSDH patients who were treated with burr-hole evacuation and MMAE (6/8 patients, 75% of the total) and postoperative follow-up with both CT and US via a sonolucent cranial cover. cSDH thickness was measured pre- and postoperatively on CT, as well as during outpatient follow-up, and compared to US. Quantitative assessment of local hematoma thickness was carried out at all time points.

Methods

Study population

Patients with a diagnosis of cSDH on CT or MRI who underwent burr-hole evacuation with or without the insertion of a subdural drain were included in the study. Nine patients were prospectively enrolled in the study, and data were retrospectively analyzed. Surgeries were performed between September 1 and November 30, 2025. CT and US studies from twelve clinic follow-up visits were completed between October 1, 2025, and January 6, 2026.

FDA-approved Sonolucent 1.4-cm slotted and nonslotted polymethyl methacrylate (PMMA) burr-hole covers (Longeviti Neuro Implants, Baltimore, MD, USA) were used.

Institutional review board (IRB) approval was obtained for the collection and analysis of clinical and imaging data (protocol number HP-00109263). Consent was not required by the IRB. Statistical analysis was carried out using GraphPad Prism (San Diego, CA, USA). Unpaired Welch’s t test was used to compare cSDH thickness and distance between the cover and midline, with p < 0.05 denoting significance.

Surgical technique

Surgical evacuation of cSDH was obtained via the creation of two burr holes located along the frontoparietal convexity, approximately 2 cm in front and behind the coronal suture. Burr holes were made using a standard 14-mm perforator drill, the dura was incised with an 11-blade knife, and the cSDH membranes were opened with bipolar cautery. cSDH fluid was irrigated copiously until clear, and hemostasis was obtained before placing either a slotted or nonslotted sonolucent cover at one or both burr holes (Table 1). The sonolucent burr-hole cover was affixed to the skull with 4 and 5 mm titanium screws. Seven patients (77% of the cohort) also received MMAE.

Table 1.

Patients’ Demographics, as Well as Surgical Details, Presence of Subdural Membranes, and Treatment with Middle Meningeal Artery Embolization Are Included

Patient	Age	Sex	Admission exam	Type of SDH	Surgery	Surgical details	Presence of membranes	MMAE	Use of AC/AP
1	59	M	GCS 15, neuro intact	cSDH	L-sided burr holes	- 1 × 1.4 mm cover - Frontal	Yes	Yes	No
2	49	M	GCS 15, neuro intact	cSDH	L-sided burr holes	- 1 × 1.4 mm slotted cover -Parietal	Yes	Yes	No
3	69	M	GCS 15, neuro intact	cSDH	Bilateral burr holes	- 2 × 1.4 mm cover - Bilateral frontal	Yes	No	No
4	71	M	GCS 15, neuro intact	cSDH	L-sided burr holes	- 1 × 1.4 mm cover - Parietal	Yes	No	Warfarin
5	80	M	GCS 15, left arm weakness	cSDH	R-sided burr holes	- 1 × 1.4 mm cover - Frontal	Yes	Yes	Aspirin 81 mg
6	92	M	GCS 15, neuro intact	cSDH	R-sided burr holes	- 1 × 1.4 mm cover - Parietal.	Yes	Yes	Apixaban 5BID
7	66	M	GCS 15, left side weakness	cSDH	R-sided burr holes	- 2 × 1.4 mm covers - Frontal slotted/parietal	Yes	Yes	Aspirin 81 mg
8	81	M	GCS 15, left side weakness	cSDH	R-sided burr holes	- 1 × 1.4 mm cover - Frontal	Yes	Yes	Aspirin 81 mg
9	74	M	GCS 15, neuro intact	cSDH	R-sided burr holes	- 1 × 1.4 mm cover - Frontal	Yes	Yes	No

cSDH, chronic subdural hematoma; MMAE, middle meningeal artery embolization.

US assessment and image quantification

Patients with cSDH were scanned preoperatively with noncontrast head CT and CT angiography (using a delayed-phase subdural hematoma protocol) to assess for the presence of membranes. Patients also underwent postoperative noncontrast head CT immediately after cSDH evacuation and again before drain removal and discharge. Follow-up in the office with a noncontrast head CT was obtained for all the patients. Transcutaneous coronal US images with shallow and deep modes were obtained at the time of follow-up using a General Electric (GE) Venue Go ultrasound instrument (Fig. 1). Bedside US evaluation was performed by an experienced sonographer (with participation from attending/resident/nurse practitioner). Shallow- and deep-mode images were stored for interpretation after being reviewed by the neurosurgery staff.

FIG. 1.

Timeline of pre- and postoperative scans. (A) Schematic of burr hole cover insertion (left) and bedside ultrasound evaluation (right). (B) Noncontrast head CTs are obtained on admission, after surgery and at the outpatient follow-up appointment. A “subdural protocol” delayed CTA head scan is also obtained on admission to study the cSDH membranes. Outpatient bedside US is performed during the follow-up visit. CT, computerized tomography; cSDH, chronic subdural hematoma; US, ultrasound; CTA, CT angiography; F/u, follow-up; GCS, Glasgow Coma Score.

Shallow-mode US images were used to measure hematoma thickness, and deep-mode was employed for midline measurement.

Plate-brain surface as well as dura-brain surface distances were calculated (Fig. 2A–C). A perpendicular trajectory from the midcoronal point f the inner plate and the septum pellucidum was measured on US (Fig. 2E, F). A similar measurement on coronal CT cuts was also performed, using a perpendicular trajectory from the plate midpoint to the septum pellucidum (Fig. 2G).

FIG. 2.

(A) Point-of-care US image obtained during outpatient follow-up of patient #3 right-sided cSDH. Absolute collection thickness was measured on ImageJ and scaled to the image scale bar. (B) Inner cover-to-brain surface distance was assessed on coronal cuts of a noncontrast CT head obtained during the same appointment. (C) Dura-to-brain distance was also measured and compared to pre- and postoperative scans. (D) Inner cover-to-brain surface distance calculated on US and CT scans was compared. A nonsignificant difference between the two techniques was noted. (E) An orthogonal trajectory between the inner plate and the patient septum pellucidum was designed and measured using ImageJ. (F) Artificial intelligence–assisted anatomical labeling of the main structures identified by trans-burr-hole US. (G) Inner cover-to-midline distance measurement on coronal CT cuts. (H) Comparison of US and CT measurements of inner cover-to-midline distance. No significant difference was found between the two techniques. CT, computerized tomography; cSDH, chronic subdural hematoma; US, ultrasound.

For CT scans, measurements of cSDH thickness and the distance from the burr-hole inner cover to the midline were calculated using Unity software (Mach7 Software, South Burlington, VT, USA). Measurements were performed on CT scans obtained before surgery, immediately after cSDH evacuation, and at the time of follow-up.

US images were quantified using ImageJ (NIH, Bethesda, MD, USA). Scans obtained at the time of the first and/or second outpatient follow-up were evaluated. Distances were measured using the “straight line” measurement tool. Line length was scaled to a scale bar, and absolute length in millimeters was calculated. Final measurements in millimeters are included in Table 3. The evaluator was blinded to the patient’s name, surgical outcomes, and CT measurements. Scans for all the included US pictures obtained are included in the Supplementary Data.

Table 3.

Follow-Up Inner Cover-to-Brain Surface Thickness as Measured on Bedside US and CT During Follow-Up Appointment

Patient	F/u US thickness at burr hole (cover to cortex mm)	F/u CT thickness at burr hole (cover to cortex mm)	F/u US distance from midline (mm)	F/u CT distance from midline (mm)
1	6	7	50	60
f/u	5.5	6	59.6	63
2	10.5	5	—	63
3
R	7.7	9	74	68
L	5	8	53	66
4	12.5	7	99	70
5	9.6	15	68	66
f/u	7.1	10	68	60
6	18	18	70	71
f/u	6.4	8	74	70
7	16	24	63	73
8	7.3	9	61	62
Statistics	NS (p = 0.57; mean US 9.3 mm; mean CT 10.5 mm)		NS (p = 0.68; mean US 67.6 mm; mean CT 65.9 mm)

US and CT inner cover-to-midline distance is also listed for each patient/appointment.

CT, computerized tomography; US, ultrasound.

RESULTS

Nine consecutive patients with cSDH who were treated with burr-hole evacuation and placement of a sonolucent burr-hole cover were included. All patients were male, and the average age was 71 years. On admission, all patients demonstrated a Glasgow Coma Score of 15, and three showed mild contralateral weakness. All the cSDHs exhibited subdural membranes, and seven patients (7/9, 77%) underwent MMAE. One patient was on warfarin on admission, one on apixaban, and three on aspirin (Table 1). Anticoagulants and antiplatelet agents were reversed before surgical evacuation.

Eight patients had unilateral placement of sonolucent burr-hole covers, and one subject had bilateral cSDH evacuation and sonolucent burr-hole cover placement. Ten total sonolucent covers were implanted. Four sonolucent covers were placed over the parietal squama and six on the frontal bone (Table 1). There were no immediate complications or infections related to the sonolucent burr-hole covers. The mean follow-up was 28 days after the surgery.

On immediate postoperative scans, a significant reduction in hematoma size was measured on CT. Maximum preoperative cSDH thickness decreased from 23.3 mm to 13.6 mm (p < 0.01). Further reduction in thickness was measured on the follow-up noncontrast head CT (average 9.4 mm, p < 0.01) (Table 2, Fig. 3A–C). We performed point-of-care US assessment in all nine patients at their first appointment and in three patients during the second postsurgical appointment (patients #1, #5, and #6). Patient #3 received bilateral cSDH evacuation and sonolucent covers. Thirteen data points were considered for the final analysis. The distance between the inner surface of the cover and the brain surface was measured on US and CT. This was performed retrospectively and in a blinded fashion using ImageJ, and the absolute measurement in pixels was scaled to the scale bar and the length in millimeters calculated (Fig. 2A; all scans with measurement and scale bars are available in Supplementary Data). Coronal CT images at the plate midpoint were used for comparison. At follow-up, the mean US-measured distance between the plate and the brain surface was 8.2 mm, while it was 10.7 mm on CT (p = 0.2) (Table 3, Fig. 2A–D). Importantly, in patient #7, cSDH recurrence/persistence was detected with both modalities, leading to additional craniotomy after the follow-up appointment.

FIG. 3.

(A) Preoperative coronal CT view of a right chronic hemispheric hematoma. A smaller contralateral collection is also visible. (B) Burr-hole evacuation of the cSDH. A sonolucent plate is visible, as well as a small amount of air underneath the implant. (C) Postsurgical changes in maximum hematoma thickness before surgery, after burr-hole evacuation, and during outpatient follow-up. A significant reduction in thickness is noted at both timepoints following the surgery. CT, computerized tomography; cSDH, chronic subdural hematoma.

Table 2.

Pre- and Postoperative cSDH Imaging Characteristics Measured on Coronal CT Cuts at the Point of Maximum Thickness

Patient	Preop SDH max thickness (mm)	Postop SDH max thickness (mm)	Postop SDH thickness at burr hole (cover to cortex mm)	Postop SDH thickness at burr hole (mm)
1	20	12	12	7
2	23	5	10	4
3
R	22	18	18	13
L	23	14	12	5
4	13	8	7	3
5	25	17	19	13
6	23	14	16	9
7	34	24	20	17
8	28	9	11	5

Follow-up CT thickness measured as the inner cover-to-brain surface distance and dura-to-brain surface distance.

CT, computerized tomography; cSDH, chronic subdural hematoma.

To assess concordance between the two modalities, the distance between the sonolucent plate and the brain’s midline was calculated. An average distance of 67.2 mm was calculated on US and of 65 mm on CT (p = 0.53, Table 3, Fig. 2H).

Discussion

Transcranial US via sonolucent burr-hole covers is emerging as a supplemental imaging modality for postoperative evaluation of cSDH.

While CT and MRI allow for high-resolution images of the cSDH, brain parenchyma, CSF spaces, meningeal layers, and the calvarium, they have drawbacks. CT is in fact expensive (∼$1000 per scan), requiring transport off the unit and exposing the patient to radiation. MRI, while allowing for high-resolution images, is even more expensive and time-consuming, requiring longer times away from the hospital unit that can be critical for complex neurosurgical patients.

The use of sonolucent implants has gained traction over the last decade. First-in-human studies have demonstrated their safety in traumatic brain injury,¹⁹ Chiari malformation,²⁰ oligodendroglioma,²¹ adult hydrocephalus,¹⁷ and extracranial to intracranial bypasses.²² Their use is particularly advantageous for pathologies that require serial follow-up imaging to evaluate persistence or recurrence of the primary pathology.

Here we present the first prospectively collected and retrospectively analyzed series of cSDH patients treated with burr-hole evacuation and MMAE and systematically followed with postoperative CT head and bedside US at follow-up. US assessment using a sonolucent burr-hole cover showed good concordance with CT for detecting and ruling out recurrent cSDH in a small cohort of patients. Importantly, it proved feasible and reproducible in the outpatient setting.

The high risk of recurrence of cSDH, estimated to be as high as 30% in surgical cohorts, makes this pathology an ideal candidate for postoperative follow-up with bedside US. Patients with cSDH undergo, in fact, a significant number of inpatient and outpatient scans, mainly noncontrast head CTs, to evaluate for hematoma reabsorption, new bleeds, and drain position. Follow-up is usually thorough, allowing for direct comparison of US pictures with images obtained at different timepoints and CT scans performed during the same visit. Further, burr holes are usually placed at the points of maximum cSDH thickness, making these areas ideal spots to estimate, with US, the overall trajectory of the collection with US. Interestingly, the only patient with cSDH persistence that required a new surgery (craniotomy) had a visible collection on US and CT, with similar thickness.

Surgical technique and image assessment

cSDH evacuation via burr holes is a common technique, with and without concurrent placement of a subdural drain. Standard-size burr holes are usually employed, measuring 14 mm in diameter. A nonslotted cover is employed in patients who did not receive a subdural drain, while a slotted version of the same was used to allow for insertion of a catheter. Standard titanium screws were used to anchor the plate to the surrounding skull, and no cases of skin breakdown or wound infection were recorded.

Given the hemispheric distribution of cSDH and the limited peripheral window that can be achieved with sonolucent implants in objects close to the brain convexity, we elected to use local hematoma thickness as a measure of cSDH.²³ To further validate US as an alternative to CT, we also measured the distance between the midpoint of the cranial plate and the brain midline (septum pellucidum) with both techniques. These measurements were not statistically different between CT and US scans.

Current costs and future directions

These are the advantages and disadvantages of using this surgical implant.

Inpatient imaging

Although sonolucent implants have a higher cost than standard titanium covers, they could potentially allow for downstream savings for the health care system and the patients. From a surgical perspective, the use of 14 mm covers without drilling/expansion of the burr hole requires no additional time compared to the use of titanium plates. In unstable patients or in those that require frequent imaging postoperatively, point-of-care US could also allow for more frequent bedside evaluation of residual collections or new bleeds without transporting the patient off the hospital unit. As US units become more available in rehabilitation hospitals, this imaging modality could be used to daily track the hematoma size, especially if supported by artificial intelligence algorithms to facilitate image interpretation.

Outpatient imaging

First, with point-of-care US becoming more widespread among neurosurgical practices, it is foreseeable that in the future outpatient CT scans will be reserved only for patients at high risk of cSDH persistence/recurrence and for those with neurological changes. This will significantly reduce the number of scans for cSDH care.

Further, the neurosurgeon will be able to capture the revenue related to US imaging, and faster picture acquisition could also allow for scheduling more appointments within the same outpatient clinic time, making the practice more efficient.

Image acquisition and accessibility

While other pathologies necessitate wider or deeper fields of view, cSDH has the advantage of being located immediately beneath the calvarium. This allows for higher resolution, easier US interpretation, and likely a steeper learning curve. In the future, protocols focused on the following will likely contribute to cSDH care. (1) Real-time characterization of neovascularization in subdural membranes; (2) artificial intelligence-supported interpretation of relevant subdural and intraparenchymal structures; and (3) automated software to identify the brain midline and establish the presence of midline shift.

Finally, a learning curve in performing and interpreting US images is certainly present. This technique will get easier as more surgeons, residents, and advanced practice providers become accustomed to this technology. By improving resolution, introducing new methods for quantitation, and adopting specific workflows, we believe that point-of-care US will provide a useful tool for cSDH care.

Limitations

Several limitations are present in our study. First, patients were not randomized, and no specific criteria were used to decide which patients were implanted with a sonolucent burr-hole cover. While blinding was not possible at the time of image acquisition, images were measured in a blinded fashion.

Furthermore, most patients received only one sonolucent cover, thereby limiting our knowledge of the cSDH trajectory. Finally, US use is limited in the first days after surgery by the presence of pneumocephalus and air underneath the skin/implant. Its clinical use therefore became possible only weeks after the initial surgery.

Conclusion

Here we present a small series of cSDH patients treated with burr-hole evacuation and placement of a sonolucent cranial implant for postoperative point-of-care US assessment. This allowed follow-up US imaging of the residual cSDH in the clinic and direct comparison of point-of-care images with non-contrasted head CT coronal scans obtained during the same visit. Importantly, the absolute thickness at the burr hole as well as the distance between the plate and the midline were not statistically different between the two modalities.

Transcutaneous trans-burr-hole US is a feasible alternative for real-time evaluation of cSDH thickness postoperatively in patients with sonolucent covers.

Transparency, Rigor, Reproducibility

To improve rigor, transparency, and reproducibility, ultrasound measurements were performed by an author (R.S.) blinded to the patient characteristics, clinical history, outcomes, and most importantly to the measurements obtained on the CT scan. Statistical analyses were carried out using Prism software. All data and materials included in these studies will be freely shared with any interested party. The data that support the findings of this study are available from the authors and are uploaded in the Supplementary Data.

Authors’ Contributions

R.S., J.R.S., M.L.R., C.L., M.S., S.K.Y., K.T.K., C.L., and J.T.K. acquired the data. R.S. interpreted the data. R.S., T.J.C., and G.T.S. wrote the article. R.S. and G.T.S. designed the experiments and analyzed and interpreted the data. J.A.S., G.F.W., J.M.S., B.A., T.J.C., and G.T.S. analyzed and interpreted the experiments and radiological techniques, provided review and editing, and wrote the article. All authors approved the final version of the article.

Supplemental Material

sj-jpeg-1-ntr-10.1177_2689288X261435806 — Supplemental material for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma

Supplemental material, sj-jpeg-1-ntr-10.1177_2689288X261435806 for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma by Riccardo Serra, Jordan R. Saadon, Maureen L. Rakovec, Kevin T. Kim, Maureen Scarboro, Cara Lomangino, Steven K. Yarmoska, Catherine Lei, John T. Kim, Jesse A. Stokum, J. Marc Simard, Graeme F. Woodworth, Bizhan Aarabi, Timothy J. Chryssikos, and Gary T. Schwartzbauer

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Supplemental material, sj-jpeg-2-ntr-10.1177_2689288X261435806 for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma by Riccardo Serra, Jordan R. Saadon, Maureen L. Rakovec, Kevin T. Kim, Maureen Scarboro, Cara Lomangino, Steven K. Yarmoska, Catherine Lei, John T. Kim, Jesse A. Stokum, J. Marc Simard, Graeme F. Woodworth, Bizhan Aarabi, Timothy J. Chryssikos, and Gary T. Schwartzbauer

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Supplemental material, sj-jpeg-3-ntr-10.1177_2689288X261435806 for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma by Riccardo Serra, Jordan R. Saadon, Maureen L. Rakovec, Kevin T. Kim, Maureen Scarboro, Cara Lomangino, Steven K. Yarmoska, Catherine Lei, John T. Kim, Jesse A. Stokum, J. Marc Simard, Graeme F. Woodworth, Bizhan Aarabi, Timothy J. Chryssikos, and Gary T. Schwartzbauer

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Supplemental material, sj-jpeg-4-ntr-10.1177_2689288X261435806 for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma by Riccardo Serra, Jordan R. Saadon, Maureen L. Rakovec, Kevin T. Kim, Maureen Scarboro, Cara Lomangino, Steven K. Yarmoska, Catherine Lei, John T. Kim, Jesse A. Stokum, J. Marc Simard, Graeme F. Woodworth, Bizhan Aarabi, Timothy J. Chryssikos, and Gary T. Schwartzbauer

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Supplemental material, sj-jpeg-5-ntr-10.1177_2689288X261435806 for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma by Riccardo Serra, Jordan R. Saadon, Maureen L. Rakovec, Kevin T. Kim, Maureen Scarboro, Cara Lomangino, Steven K. Yarmoska, Catherine Lei, John T. Kim, Jesse A. Stokum, J. Marc Simard, Graeme F. Woodworth, Bizhan Aarabi, Timothy J. Chryssikos, and Gary T. Schwartzbauer

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Supplemental material, sj-jpeg-6-ntr-10.1177_2689288X261435806 for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma by Riccardo Serra, Jordan R. Saadon, Maureen L. Rakovec, Kevin T. Kim, Maureen Scarboro, Cara Lomangino, Steven K. Yarmoska, Catherine Lei, John T. Kim, Jesse A. Stokum, J. Marc Simard, Graeme F. Woodworth, Bizhan Aarabi, Timothy J. Chryssikos, and Gary T. Schwartzbauer

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Supplemental material, sj-jpeg-7-ntr-10.1177_2689288X261435806 for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma by Riccardo Serra, Jordan R. Saadon, Maureen L. Rakovec, Kevin T. Kim, Maureen Scarboro, Cara Lomangino, Steven K. Yarmoska, Catherine Lei, John T. Kim, Jesse A. Stokum, J. Marc Simard, Graeme F. Woodworth, Bizhan Aarabi, Timothy J. Chryssikos, and Gary T. Schwartzbauer

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Supplemental material, sj-jpeg-8-ntr-10.1177_2689288X261435806 for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma by Riccardo Serra, Jordan R. Saadon, Maureen L. Rakovec, Kevin T. Kim, Maureen Scarboro, Cara Lomangino, Steven K. Yarmoska, Catherine Lei, John T. Kim, Jesse A. Stokum, J. Marc Simard, Graeme F. Woodworth, Bizhan Aarabi, Timothy J. Chryssikos, and Gary T. Schwartzbauer

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Supplemental material, sj-jpeg-9-ntr-10.1177_2689288X261435806 for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma by Riccardo Serra, Jordan R. Saadon, Maureen L. Rakovec, Kevin T. Kim, Maureen Scarboro, Cara Lomangino, Steven K. Yarmoska, Catherine Lei, John T. Kim, Jesse A. Stokum, J. Marc Simard, Graeme F. Woodworth, Bizhan Aarabi, Timothy J. Chryssikos, and Gary T. Schwartzbauer

Supplemental Material

sj-jpeg-10-ntr-10.1177_2689288X261435806 — Supplemental material for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma

Supplemental material, sj-jpeg-10-ntr-10.1177_2689288X261435806 for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma by Riccardo Serra, Jordan R. Saadon, Maureen L. Rakovec, Kevin T. Kim, Maureen Scarboro, Cara Lomangino, Steven K. Yarmoska, Catherine Lei, John T. Kim, Jesse A. Stokum, J. Marc Simard, Graeme F. Woodworth, Bizhan Aarabi, Timothy J. Chryssikos, and Gary T. Schwartzbauer

Supplemental Material

sj-jpeg-11-ntr-10.1177_2689288X261435806 — Supplemental material for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma

Supplemental material, sj-jpeg-11-ntr-10.1177_2689288X261435806 for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma by Riccardo Serra, Jordan R. Saadon, Maureen L. Rakovec, Kevin T. Kim, Maureen Scarboro, Cara Lomangino, Steven K. Yarmoska, Catherine Lei, John T. Kim, Jesse A. Stokum, J. Marc Simard, Graeme F. Woodworth, Bizhan Aarabi, Timothy J. Chryssikos, and Gary T. Schwartzbauer

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Supplemental material, sj-jpeg-12-ntr-10.1177_2689288X261435806 for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma by Riccardo Serra, Jordan R. Saadon, Maureen L. Rakovec, Kevin T. Kim, Maureen Scarboro, Cara Lomangino, Steven K. Yarmoska, Catherine Lei, John T. Kim, Jesse A. Stokum, J. Marc Simard, Graeme F. Woodworth, Bizhan Aarabi, Timothy J. Chryssikos, and Gary T. Schwartzbauer

Supplemental Material

sj-jpeg-13-ntr-10.1177_2689288X261435806 — Supplemental material for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma

Supplemental material, sj-jpeg-13-ntr-10.1177_2689288X261435806 for Transcranial Ultrasound Monitoring of Chronic Subdural Hematoma by Riccardo Serra, Jordan R. Saadon, Maureen L. Rakovec, Kevin T. Kim, Maureen Scarboro, Cara Lomangino, Steven K. Yarmoska, Catherine Lei, John T. Kim, Jesse A. Stokum, J. Marc Simard, Graeme F. Woodworth, Bizhan Aarabi, Timothy J. Chryssikos, and Gary T. Schwartzbauer

Footnotes

Acknowledgment

The authors thank the Department of Neurosurgery for the support and guidance throughout the entire project.

Author Disclosure Statement

The authors have no competing interests to disclose.

Funding Information

There was no funding provided for this research except for the technical support of the Shock Trauma Center and the Department of Neurosurgery, University of Maryland School of Medicine.

Ethics Approval

The University of Maryland and the Shock Trauma Institutional Review Board reviewed and approved the project under the IRB #HP-00109263.

Abbreviations Used

References

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Supplementary Material

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Patient	Preop SDH max thickness (mm)	Postop SDH max thickness (mm)	Postop SDH thickness at burr hole (cover to cortex mm)	Postop SDH thickness at burr hole (mm)
1	20	12	12	7
2	23	5	10	4
3
R	22	18	18	13
L	23	14	12	5
4	13	8	7	3
5	25	17	19	13
6	23	14	16	9
7	34	24	20	17
8	28	9	11	5

Patient	Preop SDH max thickness (mm)	Postop SDH max thickness (mm)	Postop SDH thickness at burr hole (cover to cortex mm)	Postop SDH thickness at burr hole (mm)
1	20	12	12	7
2	23	5	10	4
3
R	22	18	18	13
L	23	14	12	5
4	13	8	7	3
5	25	17	19	13
6	23	14	16	9
7	34	24	20	17
8	28	9	11	5

Patient	Preop SDH max thickness (mm)	Postop SDH max thickness (mm)	Postop SDH thickness at burr hole (cover to cortex mm)	Postop SDH thickness at burr hole (mm)
1	20	12	12	7
2	23	5	10	4
3
R	22	18	18	13
L	23	14	12	5
4	13	8	7	3
5	25	17	19	13
6	23	14	16	9
7	34	24	20	17
8	28	9	11	5