Two-Stage Anatomic Myocutaneous Flap Dissection in Cranioplasty: Technical Nuances and Single-Surgeon Experience.

BACKGROUND AND OBJECTIVES: Temporalis muscle management remains one of the most challenging aspects of cranioplasty, which accounts for considerable rates of dissection-related complications. Since 2019, the senior author has developed and consistently used a methodical, two-stage anatomic dissection technique to separate the scalp and temporalis muscle from the underlying brain. This technique is believed to facilitate dissection and minimize the risk of brain injury, while optimizing cosmetic outcomes. METHODS: All patients who underwent cranioplasty between January 2019 and February 2023 were identified from a prospectively maintained database. Charts were retrospectively reviewed. Demographic, clinical, and procedural data were extracted and analyzed. RESULTS: Twenty-nine patients, 20 men and 9 women with a median age of 37 years (range 17-72), were identified. Indications for craniectomy were traumatic brain injury in 18 (62.1%), hemorrhagic stroke in five (17.2%), ischemic stroke in four (13.8%), and aneurysmal subarachnoid hemorrhage in two (6.9%). Median precranioplasty modified Rankin Scale and Glasgow Coma Scale scores were 5 (range in series: 0-5) and 14 (range in series: 3-15), respectively. The median time to cranioplasty was 131 days (32-1717). Cranioplasty was technically successful in all patients, with a median operative time of 106 minutes (62-182). There were no intraoperative complications. Postoperative complications occurred in three patients (10.3%): hemorrhagic brain contusion (n = 1), meningitis (n = 1), and seizure (n = 1). Of those, one patient (3.4%) died 2 weeks after surgery from suspected pulmonary embolism. After a median follow-up of 4 months (1-44), all 28 survivors have either remained clinically stable or exhibited neurological improvement. Cosmetic results were good or excellent in 27 (96.4%) and fair in one (3.6%). CONCLUSION: Two-stage anatomic dissection of the scalp and temporalis muscle during cranioplasty can maximize surgical efficiency and result in excellent outcomes. Cranioplasty should be considered a low-risk, low-complexity neurosurgical procedure. Safe and efficient management of the temporalis muscle is key.

Emergency decompressive surgery in patients with transtentorial brain herniation and pupillary abnormalities: the importance of improved pupillary response after osmotherapy and surgery.

OBJECTIVE: The predictors of survival and functional recovery following emergency decompressive surgery in patients with transtentorial brain herniation, particularly those with pupillary abnormalities, have not been established. In this study, the authors aimed to assess the outcome of patients with intracranial mass lesions, transtentorial brain herniation, and nonreactive mydriasis, following emergency surgical decompression. METHODS: A retrospective chart review was performed of all patients with transtentorial herniation and pupillary abnormalities who underwent craniotomy or craniectomy at two trauma and stroke centers between 2016 and 2022. The functional outcome was determined using the modified Rankin Scale (mRS). RESULTS: Forty-three patients, 34 men and 9 women with a mean age of 47 years (range 16-92 years), were included. The underlying etiology was traumatic brain injury in 33 patients, hemorrhagic stroke in 8 patients, and tumor in 2 patients. The median preoperative Glasgow Coma Scale score was 3 (range 3-8), and the median midline shift was 9 mm (range 1-29 mm). Thirty-two patients (74.4%) had bilaterally fixed and dilated pupils. The median time to surgery (from pupillary changes) was 133 minutes (mean 169 minutes, range 30-900 minutes). Eighteen patients (41.9%) died postoperatively. After a median follow-up of 12 months (range 3-12 months), 11 patients (26.8%) had a favorable functional outcome, while 10 remained severely disabled (mRS score 5). On univariate analysis, younger age (p < 0.001), less midline shift (p = 0.049), and improved pupillary response after osmotic therapy (p < 0.01) or decompressive surgery (p < 0.001) were associated with favorable outcomes at 3 months. CONCLUSIONS: With aggressive medical and surgical management, patients with transtentorial brain herniation, including those with bilaterally fixed and dilated pupils, may have considerable rates of survival and functional recovery. Young age, less midline shift, and improved pupillary response following osmotic therapy or decompressive surgery are favorable prognosticators.

Gunshot Wound to the Posterior Fossa With a Transcerebellar Retromesencepahlic Bullet Path, Transient Mutism, and Unexpected Functional Recovery: The Pivotal, Energy-Absorbing Function of the Petrous Bone and Tentorial Leaflet.

Given the abundance of vital neurovascular structures, gunshot wounds (GSWs) to the posterior fossa are generally fatal. We present a unique such case where a bullet entered the petrous bone, traversed the cerebellar hemisphere and overlying tentorial leaflet, and reached the dorsal aspect of the midbrain, resulting in transient cerebellar mutism with an unexpectedly favorable functional recovery. A 17-year-old boy sustained a GSW to the left mastoid region with no exit wound and presented with agitation and confusion, ultimately leading to a coma. Head CT revealed a bullet trajectory through the left petrous bone, left cerebellar hemisphere, and left tentorial leaflet, with a retained bullet fragment in the quadrigeminal cistern, overlying the dorsal aspect of the midbrain. Computed tomography venography (CTV) demonstrated thrombosis of the left transverse and sigmoid sinuses and the internal jugular vein. The patient's hospital course was marked by the development of obstructive hydrocephalus, secondary to delayed cerebellar edema with fourth ventricular effacement and aqueductal compression, possibly worsened by concomitant left sigmoid sinus thrombosis. Following the emergency placement of an external ventricular drain and two weeks of mechanical ventilation, the patient's level of consciousness improved significantly, with excellent brainstem and cranial nerve function, ultimately leading to successful extubation. Although the patient exhibited cerebellar mutism secondary to his injury, his cognitive abilities and speech improved significantly during rehabilitation. At his three-month outpatient follow-up, he was ambulatory, independent in his daily living activities, and able to verbally communicate using full sentences. Though exceptional, survival and functional recovery may occur after a GSW to the posterior fossa. A basic understanding of ballistics and the importance of biomechanically resilient anatomic barriers, such as the petrous bone and tentorial leaflet, can help predict a good outcome. Lesional cerebellar mutism tends to have a favorable prognosis, especially in young patients with central nervous system plasticity.

Skull Reconstruction Using a Custom-Made, Three-Dimensional-Printed, Hydroxyapatite-Titanium Cranioplasty Implant: Largest Single-Center U.S. Experience.

OBJECTIVE: Although several material options, both natural and synthetic, are available for cranioplasty, the rate of implant-related complications has remained high. A relatively novel, synthetic hydroxyapatite-titanium implant, which combines biocompatibility with biomechanical resilience, has been reported to reduce tissue inflammation, infection, and explantation rates, while delivering superior cosmetic results. However, despite such promising preliminary reports, clinical data supporting its use have remained scarce. METHODS: All the patients who had undergone cranioplasty between 2019 and 2022 using this implant were identified from a prospectively maintained database. Medical records were retrospectively reviewed and the following variables recorded: demographic data, clinical data, radiologic findings, operative details, complications (implant-related and unrelated), and outcomes. RESULTS: A total of 18 patients (12 men and 6 women), with a mean age of 39 years (range, 20-70 years), were identified. The indications for craniectomy were traumatic brain injury (n = 13; 72.2%), hemorrhagic stroke (n = 3; 16.7%), and ischemic stroke (n = 2; 11.1%). The median time to cranioplasty was 140 days (range, 51-1717 days). The median modified Rankin scale score before cranioplasty was 4 (range, 0-5). Cranioplasty was technically successful in all 18 patients. Minor postoperative complications, none related to the implant, were managed conservatively in 3 patients (16.6%), including a small intraparenchymal hematoma in 1, an extra-axial hematoma in 1, and a seizure in 1. Of these 3 patients, 1 (5.6%) died 1 week later of a suspected pulmonary embolism. No implant-related complications occurred after a median follow-up of 6 months (range, 1-38 months). All 17 survivors exhibited some degree of neurologic improvement. The cosmetic result was good or excellent for all patients. CONCLUSIONS: Our experience, the largest in the United States, confirms the previously reported benefits associated with the use of 3-dimensional-printed hydroxyapatite-titanium cranioplasty implants.

Bilaterally Fixed and Dilated Pupils Are Not the Kiss of Death in Patients with Transtentorial Herniation: A Single Surgeon's Experience.

BACKGROUND: Bilaterally fixed and dilated pupils in the setting of transtentorial herniation have traditionally been considered a sign of futility. Such patients are often denied life-saving surgery based on the premise that meaningful functional recovery would be extremely unlikely. We sought to determine the survival and functional outcome in a cohort of patients who underwent aggressive medical and surgical management. METHODS: Charts of all patients managed by a single surgeon over a 42-month period were retrospectively reviewed. Functional outcome was determined using modified Rankin Scale (mRS). Outcome was classified as good (mRS score 0-3), acceptable (mRS score 4), or poor (mRS score 5-6). RESULTS: Patients were 7 men and 2 women with a mean age of 36 years (range, 16-66 years). Etiologies included stroke (4 patients), traumatic brain injury (4 patients), and malignant cerebral edema (1 patient). Preoperative Glasgow Coma Scale scores ranged from 3 to 7, and midline shift was 7-16 mm. All patients received emergency osmotic therapy before decompressive surgery. Time to surgery (from pupillary changes) was <150 minutes for all patients (median 94 minutes; range, 50-148 minutes). At 3 months, 5 patients (55.6%) had recovered, achieving a good (n = 3) or acceptable (n = 2) outcome. The other 4 patients failed to recover and ultimately died of their injury. CONCLUSIONS: In well-selected patients with transtentorial herniation and bilaterally fixed and dilated pupils, aggressive and timely medical and surgical management may lead to substantial rates of survival and favorable functional outcome. Preconceived notions of a universally grim prognosis in such patients can lead to self-fulfilling prophecies.

Are Bilaterally Fixed and Dilated Pupils the Kiss of Death in Patients with Transtentorial Herniation? Systematic Review and Pooled Analysis.

OBJECTIVE: Bilaterally fixed and dilated pupils (BFDP) in the setting of transtentorial herniation due to a space-occupying lesion have traditionally been considered a sign of futility. As a result, such patients may be denied life-saving decompressive surgery, resulting in very high mortality rates. We sought to determine the survival rate and functional outcomes in patients with transtentorial herniation and BFDP following emergency decompressive surgery. METHODS: This was a systematic review of MEDLINE, Embase, Cochrane, and Google Scholar databases, using a combination of 15 prespecified keywords, according to Preferred Reporting Items for Systematic reviews and Meta-Analyses methodology. Individual patient data were extracted, pooled, and analyzed. RESULTS: Twenty-two studies totaling 503 patients were included. Study designs were as follows: prospective cohort (n = 1), retrospective cohort (n = 15), and case report (n = 6). Nearly two thirds of patients (67.7%) were male. The mean age was 41 years (range = 3-82). The median preoperative Glasgow coma scale was 3 (range = 3-6). Nearly two thirds (66.9%) underwent surgical decompression within 2 hours of pupillary changes. The mean follow-up was 7 months (range = 1-40). Two thirds (67%) died. Among survivors, 50.5% had severe disability (Glasgow outcome scale = 2-3), while 49.5% had a good outcome (Glasgow outcome scale 4-5), representing 17% of the whole population. Given the methodological limitations, the prognostic value of age, Glasgow coma scale, and time to surgery could not be determined. CONCLUSIONS: The literature suggests a rate of favorable recovery approaching 17% following decompressive surgery in patients with transtentorial herniation and BFDP, secondary to space-occupying lesions. In the setting of stroke or trauma, the clinical finding of BFDP should not be solely relied on as an indicator of futility. Prospective studies are warranted.