Shachar Zion Shemesh

Dr. Shachar Zion Shemesh

orcid

Research Focus & Metrics

Academic Career Length

2Years (2025-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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29 May 2026 in Diagnostics
Verified
Journal Article
Open access
PDF file
SSShachar Zion Shemesh
Shachar Zion Shemesh
PKPaz Kelmer
Paz Kelmer
JAJose Antonio Asprilla
Jose Antonio Asprilla
LULior Ungar
Lior Ungar
IGItay Goor-Aryeh
Itay Goor-Aryeh
LULior Ungar
Lior Ungar
Background: Trigeminal neuralgia (TN), a facial pain disorder classically characterized by recurrent brief electric-shock-like paroxysms in one or more trigeminal divisions, frequently traverses dental pathways before specialist evaluation. Conversely, dental extraction, endodontic treatment, implant procedures, and third-molar surgery may injure the inferior alveolar, superior alveolar, mental, or lingual nerves and generate painful post-traumatic trigeminal neuropathy. We sought to define the diagnostic interface between classical TN and post-dental/alveolar nerve-related trigeminal pain in a tertiary referral cohort. Methods: We performed a retrospective single-center diagnostic-pathway study using a clinical dataset comprising 672 unique patients. A dental-interface trigeminal candidate cohort was assembled from aggregated patient-level source notes and adjudicated into five prespecified phenotypes: confirmed alveolar neuropathy, post-extraction neuropathic onset, odontogenic diagnostic misclassification, mixed/uncertain dental-interface pain, and clean classical TN. Extracted variables included demographics, trigeminal branch documentation, sensory deficit, dental procedure history, post-extraction onset, MRI and neurovascular conflict language, secondary structural disease, TN-directed medication exposure, invasive treatment exposure, documented outcomes, and time from first specialist documentation to first dated invasive treatment. Results: Among 201 dental-interface trigeminal candidates, 19 patients (9.5%) had confirmed alveolar neuropathy, 31 (15.4%) had post-extraction neuropathic onset, 20 (10.0%) represented odontogenic diagnostic misclassification, 115 (57.2%) remained mixed/uncertain, and 16 (8.0%) fulfilled a clean classical TN phenotype. Overall, 114 patients (56.7%) carried explicit TN terminology somewhere in the chart. Non-classical alveolar/post-dental syndromes comprised 70 patients (34.8%). Compared with clean classical TN, this non-classical group had higher rates of documented oral sensory deficit (38.6% vs. 0.0%, p = 0.002), post-extraction onset (52.9% vs. 0.0%, p < 0.001), extraction history (61.4% vs. 0.0%, p < 0.001), and secondary structural disease (22.9% vs. 0.0%, p = 0.035). Neurovascular conflict or vascular-loop language did not distinguish non-classical alveolar/post-dental syndromes from clean classical TN (38.6% vs. 37.5%, p = 1.000). Conclusions: A substantial minority of tertiary dental-interface trigeminal referrals represented alveolar/post-dental syndromes rather than clean classical TN, even while carrying TN labels and accumulating TN-directed treatment exposure. Post-extraction onset, lower-lip/chin or intraoral sensory change, and pain persisting despite extraction should prompt careful phenotyping before classical TN-directed escalation. The alveolar–trigeminal interface can be operationalized as a recognizable diagnostic pathway with direct implications for multidisciplinary facial-pain evaluation.

6 April 2026 in Asian Spine Journal
Verified
Journal Article
Closed access
GKGil Kimchi
Gil Kimchi
SSShachar Zion Shemesh
Shachar Zion Shemesh
DLDavid Levin
David Levin
RHRan Harel
Ran Harel
Retrospective imaging evaluation using an artificial intelligence (AI)-generated model. To develop novel AI software for early prediction and identification of postoperative airway obstruction based on routine post-operative imaging. Acute postoperative airway obstruction following anterior cervical spine surgery due to edema or hematoma is rare but potentially life-threatening. No automated system currently exists to detect this complication in its early stages. All adult patients who underwent anterior cervical fusion between 2012 and 2019 at a single tertiary care center were retrospectively identified. These cases were used to develop an AI model capable of autonomously distinguishing critical airway narrowing from benign postoperative swelling. Image processing and augmentation techniques were applied to establish a segmentation model incorporating three-dimensional reconstructions for computed tomography (CT) scans and pixel analysis for plain radiographs. The Cat- Boost algorithm was harnessed to refine decision trees and generate precise predictions, which were integrated into a graphical user interface for intuitive interaction. A total of 815 anterior cervical fusion procedures were identified; 795 patients met the inclusion criteria. Respiratory complications occurred in 35 patients (4.4%), with 11 (1.3%) caused by airway obstruction. The model achieved a positive predictive value of 0.98, a negative predictive value of 0.90, a sensitivity of 0.91, and a specificity of 0.99. The AI model developed in this study showed strong potential for predicting airway compromise following anterior cervical discectomy and fusion, despite variability between CT and radiographic environments. This tool may facilitate early detection of patients at risk of postoperative airway obstruction and help distinguish benign postoperative changes from complications. Further studies are warranted to validate these initial findings.

Verified
Journal Article
Open access
PDF file
SSShachar Zion Shemesh
Shachar Zion Shemesh
PKPaz Kelmer
Paz Kelmer
JAJose Antonio Asprilla
Jose Antonio Asprilla
OCOmri Cohen
Omri Cohen
ZCZvi R. Cohen
Zvi R. Cohen
LULior Ungar
Lior Ungar
Background: Same-day or post-admission cancellation of elective surgery is associated with inefficient operating room utilization, patient distress, and disruption of coordinated perioperative care. Functional neurosurgery is particularly vulnerable to late-stage cancellation because procedural readiness depends on parallel clinical, anatomical, medication-related, device-related, and systemic considerations. Objective: This paper aims to describe the implementation of a structured preoperative review framework for functional neurosurgery and to evaluate its association with late-stage surgical cancellation after patient admission. Methods: We performed a retrospective single-center before-and-after study of consecutive functional neurosurgical procedures scheduled at Sheba Medical Center between January 2020 and December 2025. The ABCDE framework was introduced in 2023 as a structured workflow model organized around five domains: Anatomy, Bacteria, Clotting, Devices, and Elsewhere. Included procedures were deep brain stimulation, vagus nerve stimulation, focused ultrasound, intrathecal pump implantation or replacement, implantable pulse generator replacement, spinal cord stimulation, peripheral nerve stimulation, and other palliative neuromodulation procedures. The primary endpoint was late-stage cancellation, defined as cancellation after hospital admission and initiation of operative preparation. The primary comparison was between 2020–2022 and 2023–2025. A sensitivity analysis excluded 2020 because of pandemic-era disruption. Results: A total of 867 procedures were scheduled. Late-stage cancellation occurred in 16 of 407 pre-implementation procedures and 5 of 460 post-implementation procedures, corresponding to rates of 3.9% and 1.1%, respectively. The absolute risk difference was −2.8 percentage points (95% CI, −5.2 to −0.8), and the relative risk for cancellation after implementation was 0.28 (95% CI, 0.10 to 0.75). A two-sided Fisher’s exact test comparing cancellation versus non-cancellation across the pre-implementation and post-implementation periods was statistically significant (16/407 vs. 5/460; p = 0.0074). After excluding 2020, the direction of effect remained similar, but the difference was not statistically significant: 8 of 302 procedures in 2021–2022 were canceled compared with 5 of 460 in 2023–2025 (2.6% vs. 1.1%; p = 0.15). Detailed source-level attribution was incomplete for 10 of 21 cancellation events, and domain-level analyses should therefore be interpreted descriptively. Conclusions: Implementation of the ABCDE framework was associated with fewer late-stage surgical cancellations in this single-center before-and-after study. Because the design is observational, the number of events is small, and the study period overlaps with pandemic-era disruption and post-pandemic service stabilization, the findings should be interpreted as hypothesis-generating rather than causal. The framework may provide a practical structure for standardizing preoperative review in functional neurosurgery, but prospective studies with formal adherence tracking and procedure-specific analyses are needed.

9 October 2026 in Neuromodulation: Technology at the Neural Interface
Verified
Journal Article
Closed access
SSShachar Zion Shemesh
Shachar Zion Shemesh
ZHZaki Hinnawi
Zaki Hinnawi
TMTomer Maimon
Tomer Maimon
LULior Ungar
Lior Ungar

30 August 2026 in Neurocase
Verified
Journal Article
Closed access
APAmir M. Poreh
Amir M. Poreh
LULior Ungar
Lior Ungar
SSShachar Zion Shemesh
Shachar Zion Shemesh
PKPaz Kelmer
Paz Kelmer
MHMoshe Hadanei
Moshe Hadanei
ZFZeev Feldman
Zeev Feldman
Xanthogranulomas (XGs) of the choroid plexus are uncommon benign inflammatory lesions, usually discovered incidentally within the ventricular system. Although most remain asymptomatic, larger lesio...

28 April 2026 in Medicina
Verified
Journal Article
Open access
PDF file
SSShachar Zion Shemesh
Shachar Zion Shemesh
JAJose Antonio Asprilla
Jose Antonio Asprilla
PKPaz Kelmer
Paz Kelmer
OCOmri Cohen
Omri Cohen
IGItay Goor-Aryeh
Itay Goor-Aryeh
LULior Ungar
Lior Ungar
Background and Objectives: Chronic headache after craniotomy is common and may include neuropathic subtypes (scar neuroma pain, occipital neuralgia). However, no large series has quantified these phenotypes. We conducted a single-center retrospective review (n = 5624 adult craniotomy patients) to estimate the prevalence of post-craniotomy neuropathic pain and to describe its characteristics. Materials and Methods: Institutional records were screened to identify craniotomy patients referred to a multidisciplinary pain clinic (n = 272). Eligible cases were reviewed in tiers: (1) exclusion of primary headache and noncranial pain; (2) identification of “probable neuropathic cranial pain” based on documented neuropathic features (lancinating/scalp pain, trigger tenderness, dermatomal distribution); and (3) subgroup categorization into occipital neuralgia-like, supraorbital/supratrochlear neuralgia-like, and scar-site neuropathic pain phenotypes. The supraorbital/supratrochlear subgroup was defined by frontal or frontotemporal postoperative pain in the supraorbital region, local tenderness or Tinel-like hypersensitivity over the supraorbital/supratrochlear course, and/or response to supraorbital–supratrochlear nerve block. Data extracted included demographics, timing (surgery to pain referral), pain characteristics, and treatments (blocks, radiofrequency, medications). Results: Of 5624 craniotomy patients, 272 (4.8%) had pain clinic encounters. The initial review identified 124 cases with chronic post-craniotomy headache requiring follow-up; after detailed chart classification, probable neuropathic cranial pain was present in 111 cases (2% of the cohort). Among the 111 probable neuropathic cranial pain cases, the dominant regional phenotype was occipital neuralgia-like pain. In addition, eight patients (7.2%) demonstrated a supraorbital/supratrochlear neuralgia-like phenotype, predominantly after frontal or frontotemporal craniotomies. Scar-site neuropathic pain frequently coexisted with both regional phenotypes, supporting a partially overlapping spectrum rather than mutually exclusive categories. The median time from surgery to pain referral was several months (≈12–18 months). Management commonly included occipital nerve blocks (±steroid); some patients received pulsed radiofrequency ablation of the occipital nerves, and most were trialed on neuropathic analgesics (gabapentinoids, SNRIs, etc., according to neuropathic pain guidelines). Conclusions: A clinically meaningful subset of post-craniotomy patients develops chronic neuropathic cranial pain, most commonly with occipital, supraorbital/supratrochlear, or scar-related features. Because most postoperative headaches are managed through neurosurgical follow-up and improve without pain clinic referral, the present cohort likely underestimates the true burden of neuropathic post-craniotomy pain while enriching for its most refractory neuralgic presentations. This is nevertheless the subgroup that must be recognized, discussed with patients, studied prospectively, and targeted in future prevention strategies.