Network


Latest external collaboration on country level. Dive into details by clicking on the dots.

Hotspot


Dive into the research topics where Philip G.R. Schmalz is active.

Publication


Featured researches published by Philip G.R. Schmalz.


Clinical Neurology and Neurosurgery | 2015

External ventricular drain placement in the intensive care unit versus operating room: Evaluation of complications and accuracy

Paul M. Foreman; Philipp Hendrix; Christoph J. Griessenauer; Philip G.R. Schmalz; Mark R. Harrigan

OBJECTIVE External ventricular drain (EVD) placement is a common neurosurgical procedure performed in both the intensive care unit (ICU) and operating room (OR). The optimal setting for EVD placement in regard to safety and accuracy of placement is poorly defined. METHODS A retrospective chart review was performed on 150 consecutive patients who underwent EVD placement at a tertiary care center from January of 2013 to February of 2014. Clinical and radiographic data were obtained and used to compare safety and accuracy of placement between EVDs placed in the ICU versus OR. RESULTS One hundred and thirty eight patients were evaluated. Complications (hemorrhage, infection, non-functional drain) occurred in 21.5% of ICU placements and 6.7% of OR placements (p = 0.028). Grade 1, 2, and 3 placements occurred in 67.7%, 25.8%, and 6.5% of ICU placements, respectively, versus 55.6%, 42.2%, and 2.2% of OR placements (p = 0.258). No patient who received pre-placement antibiotics suffered a ventriculostomy associated infection (VAI). CONCLUSION Patients who underwent ventriculostomy placement in the ICU differed in important ways (i.e. indication for placement and the administration of pre-procedure prophylactic antibiotics) from patients treated in the OR. However, the available data suggests that complications of hemorrhage, infection, and non-functional drains may be mitigated by ventriculostomy placement in the OR.


Clinical Neurology and Neurosurgery | 2014

Chemoprophylaxis for venous thromboembolism in traumatic brain injury: A review and evidence-based protocol

Paul M. Foreman; Philip G.R. Schmalz; Christoph J. Griessenauer

Venous thromboembolism (VTE) is a recognized source of morbidity and mortality in patients suffering traumatic brain injury (TBI). While traumatic brain injury is a recognized risk factor for the development of VTE, its presence complicates the decision to begin anticoagulation due to fear of exacerbating the intracranial hemorrhagic injury. The role of chemoprophylaxis in this setting is poorly defined, leading to a wide variability in clinical practice. A comprehensive review of the literature was performed in an effort to summarize relevant data and construct a chemoprophylaxis protocol to be implemented in a Level I Trauma Center. The review reveals robust evidence regarding the safety and efficacy of chemoprophylaxis in the setting of TBI following demonstration of a stable intracranial injury. In light of this data, a protocol is assembled that, in the absence of predetermined exclusion criteria, will initiate chemoprophylaxis within 24h after the demonstration of a stable intracranial injury by computed tomography (CT).


World Neurosurgery | 2017

Ruptured Distal Anterior Choroidal Artery Aneurysm Treated with Superselective Provocative Testing and Coil Embolization

Philip G.R. Schmalz; Abdulrahman Y. Alturki; Christopher S. Ogilvy; Ajith J. Thomas

BACKGROUND AND IMPORTANCE Aneurysms of the anterior choroidal artery are uncommon, and distal anterior choroidal artery aneurysms are even rarer, with only 34 cases reported in the medical literature. These lesions have been most commonly reported in association with moyamoya disease or arteriovenous malformations. Most published experience with these aneurysms involves open surgical approaches. Reports of endovascular treatment have been in patients with lesions distal to the plexal point and have employed vessel occlusion with liquid embolic agents in preference to coil embolization. CLINICAL PRESENTATION We present a case of a ruptured distal anterior choroidal artery aneurysm located on the cisternal segment of the artery. This lesion was successfully treated with endovascular coil embolization. Additionally, the patient underwent pre-embolization superselective provocative testing with amobarbital to assess the safety of parent vessel occlusion. CONCLUSION Endovascular coil embolization for distal anterior choroidal artery aneurysms is technically feasible and may be preferable to embolization with liquid embolic agents for lesions proximal to the plexal point. This case illustrates the utility of provocative testing and efficacy of endovascular coil embolization for lesions in this unique location.


World Neurosurgery | 2018

Transarterial Onyx Embolization of Bilateral Transverse–Sigmoid Dural Arteriovenous Malformation with Transvenous Balloon Assist—Initial U.S. Experience with Copernic RC Venous Remodeling Balloon

Abdulrahman Y. Alturki; Alejandro Enriquez-Marulanda; Philip G.R. Schmalz; Christopher S. Ogilvy; Ajith J. Thomas

BACKGROUND Currently, the mainstay treatment of dural arteriovenous fistula (DAVF) involves endovascular approaches, especially for high-grade lesions. Transarterial embolization with preservation of venous sinuses has become the preferred approach due to the development of newer liquid embolic agents. For further precision during embolization, the use of temporary balloon occlusion to protect the patency of dural sinuses from the embolic agents migration has been described. METHODS A 64-year-old man presented with bilateral pulsatile tinnitus and visual decline. A diagnostic cerebral angiogram demonstrated a complex bilateral Borden type II and Cognard type IIB DAVF. Treatment was carried out endovascularly under general anesthesia in a staged fashion. In the first stage, the balloon was inflated during embolization to protect the right transverse sigmoid venous sinus system and torcula. In the second stage, the balloon was again inflated to protect the left transverse sigmoid venous sinus system and torcula during embolization. Complete obliteration of the left DAVF was achieved, and patency of the left transverse and sigmoid sinuses was preserved. Patency of the right transverse and sigmoid sinus was also conserved post procedure. RESULTS The patient was treated successfully with transarterial Onyx embolization with transvenous balloon protection of the sinus. CONCLUSIONS This case is the first reported use of the Copernic RC balloon in the United States under the compassionate use guidelines of the U.S. Food and Drug Administration. The use of this balloon is becoming a useful treatment alternative in selected cases of DAVFs as it improves the safety and efficacy of transarterial embolization as evidenced in this case.


Operative Neurosurgery | 2018

Sequential Coiling-Assisted Deployment of Flow Diverter for Treatment of Fusiform Middle Cerebral Artery Aneurysms

Abdulrahman Y. Alturki; Philip G.R. Schmalz; Christopher S. Ogilvy; Ajith J. Thomas

BACKGROUND AND IMPORTANCE Fusiform intracranial aneurysms remain challenging lesions to treat. These aneurysms have historically required bypass procedures or clip remodeling constructs for cure. Recently, endovascular specialists have reported experience with flow diversion for complex fusiform aneurysms of the vertebrobasilar system, with mixed results. Vascular anatomy for anterior circulation fusiform aneurysms may make these lesions more amenable to flow diversion and embolization procedures; however, published experience with these techniques is lacking. In this report, we describe a sequential coiling-assisted deployment of flow diverter for the treatment of fusiform middle cerebral artery (MCA-M1) aneurysms in 2 cases, 1 presenting acutely with subarachnoid hemorrhage and another with progressive aneurysm enlargement. CLINICAL PRESENTATION Two patients, a 36-yr-old male presenting with subarachnoid hemorrhage and a 60-yr-old female presenting with aneurysm enlargement were treated for fusiform aneurysms of the M1 segment of the MCA using a sequential, partial deployment of coils and flow diverter through 2 microcatheters to facilitate mutual mechanical support for both coil and flow diverter (Pipeline Embolization Device; Medtronic Inc, Dublin, Ireland). Both patients achieved favorable outcomes and follow-up angiography demonstrated complete vessel reconstruction in both cases. CONCLUSION The treatment of complex, fusiform, large vessel aneurysms remains challenging. As experience with new endovascular technologies and techniques grows, these lesions may be treated safely with interventional methods. The technique of partial flow diverter deployment and stabilization with coils with sequential delivery of both devices using dual microcatheter was both safe and effective.


World Neurosurgery | 2018

Antiplatelet Medication Reversal Strategies in Operative Intracranial Hemorrhage: A Survey of Practicing Neurosurgeons

Paul M. Foreman; Adeel Ilyas; James Mooney; Philip G.R. Schmalz; Beverly C. Walters; Christoph J. Griessenauer

BACKGROUND Antiplatelet therapy is common and complicates operative management of acute intracranial hemorrhage. Few data exist to guide antiplatelet reversal strategies. METHODS An online survey detailing antiplatelet reversal strategies in patients presenting with acute operative intracranial hemorrhage (subdural hematoma, epidural hematoma, and intracerebral hemorrhage) was distributed to board-certified neurosurgeons in North America. RESULTS From 2782 functional e-mail addresses, there were 493 (17.7%) responses to question 1 and 429 (15.4%) completed surveys. Most respondents chose to perform no additional laboratory testing before surgical intervention, regardless of hemorrhage type. The most common antiplatelet reversal strategy in the presence of aspirin was platelet transfusion (subdural hematoma and intracerebral hemorrhage) or no intervention (epidural hematoma). The most common antiplatelet reversal strategy in the presence of an adenosine diphosphate antagonist or dual antiplatelet therapy was platelet transfusion or platelet transfusion with desmopressin acetate administration. There was a statistically significant difference in management strategy depending on the antiplatelet therapy (P < 0.001). CONCLUSIONS When patients on antiplatelet medication present with operative intracranial hemorrhage, the majority of neurosurgeons do not perform qualitative platelet testing. Antiplatelet reversal strategies are significantly influenced by the antiplatelet therapy with more aggressive reversal strategies employed in the presence of ADP antagonists.


Neuro-Ophthalmology | 2018

Angiographic Findings in the Tolosa–Hunt Syndrome and Resolution after Corticosteroid Treatment

Krishnan Ravindran; Philip G.R. Schmalz; Nurhan Torun; Michael Ronthal; Yu-Ming Chang; Ajith J. Thomas

ABSTRACT The Tolosa–Hunt syndrome is a rare clinical condition characterized by painful opthalmoparesis associated with idiopathic granulomatous inflammation of the orbital apex and cavernous sinus. Historically, this condition was thought to result from arteritic changes in the internal carotid artery and cavernous sinus. Modern digital angiographic techniques were unavailable when THS was initially described, and few reports exist on its high-resolution angiographic findings. Painful ophthalmoparesis, especially of the oculomotor nerve, warrants vascular imaging because of the concern for an underlying aneurysm. Here, we describe angiographic findings of THS which may be useful for clinicians when encountering patients presenting with painful ophthalmoplegia.


Journal of Neurosurgery | 2018

Proposal of a follow-up imaging strategy following Pipeline flow diversion treatment of intracranial aneurysms

Raghav Gupta; Christopher S. Ogilvy; Justin M. Moore; Christoph J. Griessenauer; Alejandro Enriquez-Marulanda; Madeline Leadon; Nimer Adeeb; Luis C. Ascanio; Georgios Maragkos; Abhi Jain; Philip G.R. Schmalz; Abdulrahman Y. Alturki; Kimberly Kicielinski; Clemens M. Schirmer; Ajith J. Thomas

OBJECTIVEThere is currently no standardized follow-up imaging strategy for intracranial aneurysms treated with the Pipeline embolization device (PED). Here, the authors use follow-up imaging data for aneurysms treated with the PED to propose a standardizable follow-up imaging strategy.METHODSA retrospective review of all patients who underwent treatment for ruptured or unruptured intracranial aneurysms with the PED between March 2013 and March 2017 at 2 major academic institutions in the US was performed.RESULTSA total of 218 patients underwent treatment for 259 aneurysms with the PED and had undergone at least 1 follow-up imaging session to assess aneurysm occlusion status. There were 235 (90.7%) anterior and 24 posterior (9.3%) circulation aneurysms. On Kaplan-Meier analysis, the cumulative incidences of aneurysm occlusion at 6, 12, 18, and 24 months were 38.2%, 77.8%, 84.2%, and 85.1%, respectively. No differences in the cumulative incidence of aneurysm occlusion according to aneurysm location (p = 0.39) or aneurysm size (p = 0.81) were observed. A trend toward a decreased cumulative incidence of aneurysm occlusion in patients 70 years or older was observed (p = 0.088). No instances of aneurysm rupture after PED treatment or aneurysm recurrence after occlusion were noted. Sixteen (6.2%) aneurysms were re-treated with the PED; 11 of these had imaging follow-up data available, demonstrating occlusion in 3 (27.3%).CONCLUSIONSThe authors propose a follow-up imaging strategy that incorporates 12-month digital subtraction angiography and 24-month MRA for patients younger than 70 years and single-session digital subtraction angiography at 12 months in patients 70 years or older. For recurrent or persistent aneurysms, re-treatment with the PED or use of an alternative treatment modality may be considered.


Journal of Neurosurgery | 2018

Relationship between external ventricular drain clamp trials and ventriculoperitoneal shunt insertion following nontraumatic subarachnoid hemorrhage: a single-center study

Luis C. Ascanio; Raghav Gupta; Nimer Adeeb; Justin M. Moore; Christoph J. Griessenauer; Julie Mayeku; Yaw Tachie-Baffour; Ranjit Thomas; Abdulrahman Y. Alturki; Philip G.R. Schmalz; Christopher S. Ogilvy; Ajith J. Thomas

OBJECTIVECurrently, there is no established standard regarding the ideal number of external ventricular drain (EVD) clamp trials performed before ventriculoperitoneal (VP) shunt insertion following nontraumatic subarachnoid hemorrhage (SAH). In this study, the authors aimed to evaluate this relationship.METHODSA retrospective review of all patients presenting with SAH between July 2007 and December 2016 was performed. Patients with SAH who had received an EVD within the first 24 hours of hospital admission and had undergone at least 1 clamp trial prior to EVD removal were eligible for inclusion in the study. Patient demographics, clinical presentations, SAH etiologies and grades, clamp trial data, hospital lengths of stay, and functional outcomes were recorded.RESULTSOne hundred fourteen patients with nontraumatic SAH complicated by posthemorrhagic hydrocephalus were included in the study. The median patient age was 57 years (range 28-90 years), with a male/female ratio of 1:1.7. A ruptured aneurysm was the underlying etiology of SAH in 79.8% of patients. A majority of patients (69.4%) had a Hunt and Hess grade III-V on admission. The median number of clamp trials performed was 2 (range 1-6). A VP shunt was required in 40.4% of patients. In those who underwent 2 and 3 clamp trials, 60% and 38.9%, respectively, did not require subsequent VP shunt placement.CONCLUSIONSSurgical placement of a VP shunt is associated with complications. Clamp trials are routinely performed before making the decision to insert a shunt. In the present study, the authors found that a significant percentage of patients passed their second and third clamp trials without requiring subsequent shunt insertion. These data support performing multiple clamp trials prior to shunt placement.


Cureus | 2018

Use of an Absorbable Synthetic Polymer Dural Substitute for Repair of Dural Defects: A Technical Note

Philip G.R. Schmalz; Christoph J. Griessenauer; Christopher S. Ogilvy; Ajith J. Thomas

Repair of the dura after cranial neurosurgery can present a technical challenge and, for certain neurosurgical procedures, is critical to prevent cerebrospinal fluid leak and associated wound complications. Multiple options exist for dural repair, including the patient’s own tissues, bovine collagen-derived commercially available grafts, as well as newer, entirely synthetic graft materials. This is the first report of surgical experience with a new synthetic and absorbable dura substitute which has recently gained Food and Drug Administration (FDA) approval. Four patients underwent dural reconstruction with a new graft material after cranial neurosurgery when the dura was unrepairable directly. The synthetic graft material demonstrated satisfactory surgical qualities, was effective in dural repair, and no complications were attributable to the graft. Dural repair after craniotomy is an often desirable surgical outcome in neurosurgery. Surgeons seeking new graft materials may find this new absorbable, entirely synthetic material favorable for dural repair.

Collaboration


Dive into the Philip G.R. Schmalz's collaboration.

Top Co-Authors

Avatar

Ajith J. Thomas

Beth Israel Deaconess Medical Center

View shared research outputs
Top Co-Authors

Avatar

Christoph J. Griessenauer

Beth Israel Deaconess Medical Center

View shared research outputs
Top Co-Authors

Avatar

Christopher S. Ogilvy

Beth Israel Deaconess Medical Center

View shared research outputs
Top Co-Authors

Avatar

Abdulrahman Y. Alturki

Beth Israel Deaconess Medical Center

View shared research outputs
Top Co-Authors

Avatar

Paul M. Foreman

University of Alabama at Birmingham

View shared research outputs
Top Co-Authors

Avatar

Alejandro Enriquez-Marulanda

Beth Israel Deaconess Medical Center

View shared research outputs
Top Co-Authors

Avatar

Justin M. Moore

Beth Israel Deaconess Medical Center

View shared research outputs
Top Co-Authors

Avatar

Mark R. Harrigan

University of Alabama at Birmingham

View shared research outputs
Top Co-Authors

Avatar

Nimer Adeeb

Beth Israel Deaconess Medical Center

View shared research outputs
Top Co-Authors

Avatar

Raghav Gupta

Beth Israel Deaconess Medical Center

View shared research outputs
Researchain Logo
Decentralizing Knowledge