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Mardini, Samir

https://orcid.org/0000-0002-6434-4676

Mayo Clinic

Mayo Clinic

Citations 103

An Open-Source, User-Friendly Machine-Learning Method for Automated Segmentation and Analysis of Peripheral Nerve Cross-Sections
Suchyta, Marissa , Dohrmann, Beth, Mardini, Samir

Plastic & Reconstructive Surgery | January 22, 2025 | Volume: 156 | Issue: 2 | Pages: 291e-296e

10.1097/prs.0000000000011974 Get It

Background: Quantitative neuromorphometric analysis of the peripheral nerve is paramount to nerve regeneration research. However, this technique relies upon accurate segmentation and determination of myelin and axonal area. Manual histologic analysis methods are time-consuming and subject to error and bias. The authors demonstrate and validate a user-friendly method relying on open-source machine-learning software and requiring no coding knowledge. Methods: Nineteen rat facial nerve segments were fixed, osmicated, embedded in epoxy, sectioned, and stained with toluidine blue. Whole nerve cross-sections were scanned at 20×. Images were preprocessed in ImageJ to measure fascicular area and remove background. Images were imported into Ilastik, and the pixel classification module was used to segment myelin and axons. A novel CellProfiler pipeline was used with Otsu 2-threshold processing to segment and quantify individual axon and myelin objects from segmentations. Axon counts and g-ratio of nerve samples were acquired manually and using this technique to compare between methods. Results: Analysis of an entire nerve cross-section can be completed with this method in less than 5 minutes. Bland-Altman plot and intraclass correlation coefficient demonstrated reliability between axon counts performed manually and with this protocol. There was no significant difference in accuracy in determining g-ratio compared with manual techniques (P < 0.05). Conclusions: The protocol presented here demonstrates a novel and accurate means of segmenting and analyzing histologic nerve cross-sections. This method decreases both user time and potential bias, enables analysis of an entire nerve versus random sampling, and uses only open-source software freely accessible to researchers.
Optimal Time for Nevus Sebaceous Excision and Predictors of Surgical Outcomes and Secondary Intralesional Neoplasms: The Mayo Clinic Experience Over 37 Years
Pazelli, Alexandre Meira, Cherukuri, Sai , Bite, Uldis, Mandrekar, Jay , Lehman, Julia S. , Gibreel, Waleed , Meira Pazelli, Alexandre, Cherukuri, Sai K, Gibreel, Waleed , Lehman, Julia S , Davis, Dawn Marie R. , Mardini, Samir , Vierkant, Robert A.

Journal of Craniofacial Surgery | December 10, 2024 | Volume: 36 | Issue: 2 | Pages: 473-477

10.1097/scs.0000000000010910 Get It

Background: Controversy exists around the optimal timing of resection of nevus sebaceous (NS). The authors aim to determine optimal timing of NS resection and identify predictors of surgical outcomes and secondary intralesional neoplasms. Methods: Retrospective chart review of all patients with biopsy-proven NS diagnosis treated at the authors' institution between 1987 and 2024. Results: A total of 632 patients (317 females) underwent biopsy at a median age of 17 (interquartile range 11.7–36.9) years. Benign secondary intralesional neoplasms were found in 67 (10.6%) patients, with syringocystadenoma papilliferum being the most common. Malignant secondary intralesional neoplasms were diagnosed in 62 (9.8%) patients, with basal cell carcinoma being the most common. The incidence of secondary intralesional neoplasms was 3.9%, 24.4%, 36.05%, and 54%, in patients aged 0 to 20, 20 to 40, 40 to 60, and 60 to 80 years, respectively (P<0.001). Age and NS area were associated with an increased risk of developing benign and malignant intralesional neoplasms (P=0.01). Younger patients were more likely to need general anesthesia for excision (median age 10.42 versus 17 years, P<0.001). Surgical complications occurred in 10 cases, and 6 patients required unanticipated revision surgery. The risk of developing secondary intralesional neoplasms was similar across different NS anatomic regions (log-rank, P=0.09). Conclusion: Surgical excision of NS is safe and has an acceptable risk profile. The findings of this study support our historic practice of NS excision before puberty (before the accelerated growth phase) to reduce the risk of developing secondary intralesional neoplasms.
The Fate of the Frozen Bone Flap: Quantitative and Volumetric Assessment Following Cranioplasty Using the Autologous Bone Flap
Cherukuri, Sai , Zheng, Eugene E. , Pazelli, Alexandre Meira, Sears, Victoria A. , Gibreel, Waleed , Cherukuri, Sai K, Van Gompel, Jamie, Meira Pazelli, Alexandre, Gibreel, Waleed , Gompel, Jamie J. Van , Vierkant, Robert A. , Mardini, Samir , Morris, Jonathan M.

Journal of Craniofacial Surgery | December 10, 2024 | Volume: 36 | Issue: 2 | Pages: 508-512

10.1097/scs.0000000000010960 Get It

Objective: The pattern, rate, and natural history of bone flap resorption following cranioplasty with frozen, autologous bone flap has not been fully defined. The authors sought to quantify the progression and natural history of bone flap resorption. Methods: Patients who had craniectomy and delayed cranioplasty with stored, frozen bone flap between 2012 and 2022 were included in this study. Results: Ninety patients (63% male) were included, with a median age of 44.8 years (range: 4.2–84.4 y) at the time of autologous bone flap cranioplasty. Delayed, autologous cranioplasty occurred at a median time of 29.5 days (range: 2 d–10 y) from the index craniectomy. The median follow-up was 16.6 months (range: 3.4–85.4 mo). Radiographically quantifiable bone flap resorption occurred in 50 patients (56%). During the follow-up, the average percentage volume loss was 17%, with a nonlinear pattern of resorption. Following delayed, autologous cranioplasty, 11 patients had clinically significant bone flap resorption requiring secondary alloplastic cranioplasty at a median time of 13.8 months (range: 5.9–57.2 mo), with a mean percentage volume loss of 61%. Younger age was a risk factor for bone flap resorption (P < 0.05), whereas active smoking, presence of comorbidities, and number of days of bone flap storage were not risk factors for bone flap resorption. Penalized B-spline regression analysis showed that bone flap resorption followed a nonlinear pattern. Conclusion: Radiographically quantifiable bone flap resorption occurred in about 56% of patients following delayed autologous cranioplasty. Resorption followed a non-linear pattern. Young age is a risk factor for bone flap resorption.
Imaging Yield, Surgical Findings, and Outcomes Following Surgical Excision of Lateral Brow Dermoid Cysts
Gates-Tanzer, Lauren, Pazelli, Alexandre Meira, Wang, Leda, Cofer, Shelagh A. , Lehman, Julia S. , Bradley, Elizabeth H. , Gibreel, Waleed , Cofer, Shelagh, Lehman, Julia, Gibreel, Waleed , Lehman, Julia S , Davis, Dawn Marie R. , Bradley, Elizabeth, Mardini, Samir

Journal of Craniofacial Surgery | December 10, 2024 | Volume: 36 | Issue: 2 | Pages: 465-468

10.1097/scs.0000000000010907 Get It

Purpose: To review cases of lateral brow dermoid cysts and gain insight into the utility of preoperative imaging, incidence of intraorbital extension, and recurrence rate. Methods: This is a retrospective study of all patients who underwent excision of lateral brow dermoid cysts at the authors' academic center over a 37-year period. Results: A total of 136 patients were included. The median age at presentation was 5.6 months [interquartile range (IQR) 3–16.5], and the median age at removal was 1.5 years (IQR 0.9–3.4). Preoperative imaging was performed in 44 patients. Intraorbital communication was predicted in 4 patients who underwent imaging and confirmed in 6 patients (4.4%) intraoperatively. Superficial dermoids were the most common depth (n=79, 58.1%), followed by periosteal (n=37, 27.2%) and intraosseous (n=14, 10.3%). Two patients (1.4%) presented with postoperative hematoma that required surgical evacuation. Recurrence was seen in 2 patients (1.4%). Among those who completed a follow-up, the median follow-up time was 1 month (IQR 0.44–5.8 months). Conclusion: The authors' study revealed that the majority of lateral brow dermoid cysts are either superficial or involve the periosteum, with orbital involvement being rare. None of our patients demonstrated intracranial communication. Imaging did not seem to add clinical value in patients for whom there was no clinical suspicion for the involvement of the deeper tissues, so careful consideration of ordering preoperative imaging would help decrease health care costs and avoid radiation exposure, which is particularly concerning for pediatric patients. The recurrence rate of lateral brow dermoid cyst seems to be low but studies with longer follow-ups are needed.
Imaging Yield and Surgical Outcomes of Nasal, Medial Brow, Forehead, and Scalp Dermoid Cysts
Pazelli, Alexandre Meira, Wang, Leda, Gates-Tanzer, Lauren, Cofer, Shelagh A. , Lehman, Julia S. , Ahn, Edward S. , Gibreel, Waleed , Meira Pazelli, Alexandre, Cofer, Shelagh, Lehman, Julia, Guerin, Julie, Gibreel, Waleed , Lehman, Julia S , Davis, Dawn Marie R. , Mardini, Samir , Guérin, J.

The Cleft Palate Craniofacial Journal | November 4, 2024 | Volume: 63 | Issue: 1 | Pages: 126-132

10.1177/10556656241295572 Get It

Objective Dermoid cyst (DC) is a congenital cyst with the potential to have intracranial extension (ICE). This study aims to evaluate the imaging yield and surgical outcomes of nasal, medial brow, forehead, and scalp DCs. Design Retrospective review of craniofacial DCs treated at our institution between 1992 and 2024. Results A total of 117 patients (57 females) were included. The median age at cyst detection and removal were 4.8 months (IQR 3.6-9.6) and 1.8 years (IQR 0.9-5.3), respectively. In 42 patients, parents have noticed the presence of the cyst immediately after birth. Cyst wall rupture during surgical removal was reported in 15.4%. The median follow-up time was 1.3 months (IQR 0.5-12.2). Three patients experienced recurrence. No postoperative complication was reported. The regions with the highest prevalence of ICE were the forehead, frontotemporal scalp, and nasal region. The lateral frontal/temporal scalp had a 33.3% rate of ICE. Midline forehead/scalp lesions demonstrated a higher risk of ICE compared to their lateral equivalents (54.5% vs 17.5%, P = .03). The sensitivity and specificity of magnetic resonance imaging (MRI) were 100% and 95.7%, while for computed tomography (CT scans) were 72.7% and 96.5%. The Area Under the Curve for MRI was 0.978, and for CT was 0.846. The sensitivity and specificity of ultrasound were 50% and 100%. Conclusions Midline forehead/scalp DCs are more prone to extend intracranially than lateral DCs. MRI had a higher sensitivity and specificity than CT scans in detecting ICE. Routine screening imaging should be considered in midline forehead/scalp, lateral frontal/temporal, and nasal DCs.
Bridging Gaps in Health Literacy for Cleft Lip and Palate: The Role of Artificial Intelligence and Interactive Educational Materials
Shehab, Abdallah A. , Shedd, Katie E., Alamah, Waleed , Bite, Uldis, Gibreel, Waleed , Gibreel, Waleed , Mardini, Samir

The Cleft Palate Craniofacial Journal | October 9, 2024 | Volume: 63 | Issue: 1 | Pages: 65-71

10.1177/10556656241289653 Get It

Objective Our goal is to address the health literacy gap concerning cleft lip and palate using artificial intelligence (AI), specifically OpenAI's ChatGPT-4, to enhance the readability of patient educational materials (PEMs). Additionally, we aim to explore the integration of interactive educational materials into these resources. Design A cross-sectional study. Setting Websites of craniofacial teams approved by the American Cleft Palate-Craniofacial Association (ACPA). Patients/Participants PEMs collected from these websites. Interventions First, we examined the PEMs for interactive educational content such as videos, photos, case examples, and audio clips. Subsequently, we used the WebFX online readability calculator and Grammarly to evaluate the texts’ readability and clarity. After that, we used ChatGPT-4 to simplify the PEM texts to a 6th-grade reading level and re-evaluated their readability and clarity. Main Outcome Measure(s) Readability levels (grade level) and clarity scores of PEMs before and after AI modification, and the presence of interactive educational content. Results Initial evaluations using the Flesch-Kincaid Grade Level formula showed that the texts were written at a median 9th-grade reading level. Modifications using ChatGPT-4 significantly improved readability, achieving a median 6th-grade level and enhanced clarity. Only 27% of the websites featured interactive educational content, indicating a gap in utilizing educational enhancements. Conclusion The use of AI improved the readability and clarity of patient educational materials, aligning with recommended standards. However, the underutilization of interactive tools suggests a need for broader integration of these resources to optimize patient education and engagement.
Accuracy of Preoperative Imaging in Assessing the Positivity of the Deep Periosteal Margin in Dermatofibrosarcoma Protuberans of the Scalp
Cherukuri, Sai , Zheng, Eugene, Brewer, Jerry D., Guerin, Julie, Brewer, Jerry, Guérin, J. , Mardini, Samir , Gibreel, Waleed

Journal of Craniofacial Surgery | September 24, 2024 | Volume: 35 | Issue: 8 | Pages: 2313-2316

10.1097/scs.0000000000010512 Get It

The locally aggressive nature and high recurrence rate of dermatofibrosarcoma protuberans (DFSP) make it challenging to manage, especially when present on the scalp, owing to its ability to invade the underlying periosteum, bone, dura, or brain. Preoperative imaging is used to plan resection, but the true correlation between periosteal or osseous changes on imaging and the presence of tumor within the periosteum is unclear. We present our institutional experience of managing DFSP of the scalp with emphasis on the imaging used. A retrospective review of 33 patients with DFSP of the scalp treated at a tertiary center was conducted. Data on demographics, tumor characteristics, preoperative imaging (magnetic resonance imaging or computed tomography), and surgical outcomes were analyzed. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of each imaging modality were calculated. Patients underwent surgical resection at a mean age of 37.11 years and had a median follow-up of 28.34 months. Preoperative imaging was available for 26 patients (CT only: 5, MRI only: 12, CT and MRI: 9). Calvarial abnormalities were seen in 3 patients. Treatment included Mohs surgery (66.7%) and wide local excision (33.3%). In 10 patients with positive periosteal margins, bone involvement was managed by burring (7) or craniectomy (3). The sensitivity and PPV of CT for periosteal margin positivity were 25% and 100%, and for MRI were 33% and 100%, respectively. The specificity and NPV were 100% and 50% for CT, and 100% and 66% for MRI. Preoperative CT and MRI have low sensitivity and NPV but high specificity and PPV in determining depth of involvement and are essential to guiding reconstruction in DFSP of the scalp.
An Update on the Survival of the First 50 Face Transplants Worldwide
Homsy, Pauliina , Barret, Juan P. , Borsuk, Daniel E., Bula, Daniel , Infante-Cossío, Pedro , Lantieri, Laurent , Morelon, Emmanuel, Nasır, Serdar , Papay, Francis , Rodriguez, Eduardo D. , Özkan, Özlenen , Özmen, Selahattin, Huelsboemer, Lioba Franziska , Blondeel, Phillip Nicholas , Gelb, Bruce E. , Mardini, Samir , Morélon, Emmanuel , Petruzzo, Palmina , Pomahač, Bohdan , Lassus, Patrik

JAMA Surgery | September 18, 2024 | Volume: 159 | Issue: 12 | Pages: 1339

10.1001/jamasurg.2024.3748 Get It

Importance Since 2005, a total of 50 face transplants have been reported from 18 centers in 11 countries. The overall survival of the grafts has not yet been established. Objective To assess the survival of the face transplant grafts and evaluate factors potentially influencing it. Design, Setting, and Participants Data on all the transplants included in this multicenter cohort study were collected at participating transplant centers for updated nonpublished data, supplemented with literature review for nonparticipating centers. Data from 2005 until September 2023, were included. Data were analyzed from November 11, 2005, through September 18, 2023. Patients included the first 50 patients in the world to have received a face transplant. Exposure Face transplant graft. Main Outcomes and Measures The primary outcome was the overall survival of the face transplant graft, defined as either transplant loss or patient death. The secondary outcome was the number of acute rejection episodes per year. Results The 50 transplants were performed on 39 men (81%) and 9 women (19%) with a median age of 35 (range, 19-68) years at the time of the transplant. The median follow-up time was 8.9 (range, 0.2-16.7) years. During the follow-up, 6 transplants were lost with 2 patients retransplanted. There were 10 patients who died, 2 of whom had lost a transplant. The 5- and 10-year survival of the transplants was 85% (SD, 5%) and 74% (SD, 7%), respectively. The sequential number of the transplant in the world was a significant predictor of survival (hazard ratio, 95; 95% CI, 90-100; P &amp;lt; 05). The median number of acute rejection episodes per year was 1.2 (range, 0-5.3) for the transplants that were lost and 0.7 (range, 0-4.6) for the transplants that survived. No correlation with patient and transplant variables was detected for either the transplant survival or the number of rejection episodes. Conclusions and Relevance In this study, the overall survival of the face transplants is encouraging. These data suggest that the acceptable long-term survival of face transplants makes them a reconstructive option for extensive facial defects.
Localized tacrolimus therapy: innovations in peripheral nerve regeneration through advanced drug delivery systems
Millesi, Elena , Millesi, Flavia , Rechberger, Julian S. , Daniels, David J. , Radtke, Christine , Mardini, Samir

Therapeutic Delivery | September 4, 2024 | Volume: 15 | Issue: 10 | Pages: 743-748

10.1080/20415990.2024.2392481 Get It

What Free Flaps Are Surgeons Using for Palatal Fistula Repair in Patients with Cleft Palate? A Systematic Review
Zheng, Eugene E. , Gates-Tanzer, Lauren, Cherukuri, Sai , Bite, Uldis, Gibreel, Waleed , Gibreel, Waleed , Mardini, Samir , Murad, M. Hassan

The Cleft Palate Craniofacial Journal | August 23, 2024 | Volume: 62 | Issue: 9 | Pages: 1568-1577

10.1177/10556656241266243 Get It

Objective Recalcitrant palatal fistulas in patients with cleft palate history sometimes require free flap reconstruction. This study reviews the literature on described flaps and outcomes. Design A systematic review was conducted per the Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. Setting All study designs were included. Non-English articles were excluded. Patients and Participants Patients with a history of cleft palate who underwent free flap reconstruction for a oronasal fistula. Interventions Free tissue transfer for a palatal fistula repair. Main outcomee measures Information regarding defect and flap characteristics were reviewed. Surgical outcomes such as flap loss rates, rates of recurrent fistula formation, and speech outcomes were also obtained. Results Our search returned 894 articles, of which 23 were included. All studies were retrospective case series and reports. A total of 65 patients were described with an average age of 19.3 (range 3–55) years and a median fistula size of 8.00 cm 2 (range 2.54 cm 2 – 24 cm 2 ). The most common flap was the radial forearm flap (n = 37). Nine patients (13.8%) had recurrent fistula formation with surgical revision successful in all cases in which the patient returned to the operating room. There were two partial flap losses and no total flap losses. Speech outcomes showed improvement in 27 patients across 10 studies. Conclusions Palatal fistula repair with free tissue transfer is safe with an acceptable risk profile and low flap loss rate. Early recurrence due to partial flap necrosis and dehiscence are successfully managed with flap readvancement.