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.

Dural-Based Posterior Fossa Medulloblastoma Mimicking a Petrous Meningioma in Late Adulthood.

Background: Medulloblastoma of the posterior fossa is commonly encountered in pediatric populations but rarely reported in adults. Adult cases of medulloblastoma typically occur in younger patients, tend to arise intra-axially within the cerebellar hemisphere, and usually exhibit classic histopathologic features. Case Report: A 54-year-old male presented with headaches, dizziness, gait instability, and frequent falls that had worsened during the prior 3 months. Imaging and histopathologic analysis revealed extra-axial, dural-based posterior fossa medulloblastoma with desmoplastic/nodular histopathology, mimicking a petrous meningioma. The mass occupied the left cerebellopontine angle. The patient underwent microsurgical gross total resection of the tumor followed by proton beam radiation therapy and was disease-free at 1-year follow-up. Conclusion: Few dural-based posterior fossa medulloblastomas resembling petrous meningiomas have been reported, and to our knowledge, this is the first description of a case to be treated successfully with proton beam therapy in an older adult. Although rare, medulloblastoma can occur extra-axially in the cerebellopontine angle of older adults, potentially mimicking a petrous meningioma. This rare possibility should always be kept in mind, especially if expectant, nonsurgical management is being considered. To optimize outcome, posterior fossa medulloblastoma should be treated with aggressive microsurgical resection followed by radiation therapy. When available, proton beam therapy should be considered.

Sinking bullet syndrome: A unique case of transhemispheric migration.

BACKGROUND: Spontaneous migration of retained intracranial bullet fragments is an increasingly recognized phenomenon. However, such migration is usually limited in extent, since it occurs along the bullet tract or cerebrospinal fluid (CSF) spaces. Transhemispheric migration through an intact cerebral hemisphere has not been previously reported. OBSERVATIONS: A 20-year old man sustained a gunshot wound (GSW) to the head with a left parieto-occipital entry point, resulting in retained bullet fragments within the anterior right frontal lobe. The patient developed medically refractory intracranial hypertension, necessitating a left decompressive hemicraniectomy. He exhibited a favorable postoperative course, with gradual neurologic recovery, and was ultimately discharged to a rehabilitation facility. Notwithstanding, serial head CT scans during the first 2 weeks revealed gradual transhemispheric migration of bullet fragments from the right frontal pole to the right occipital pole, traveling through largely intact, uninjured brain tissue. LESSONS: Transhemispheric migration of bullet fragments via intact brain tissue may rarely occur. While the exact mechanisms underlying this phenomenon remain unclear, potential factors may include: bullet weight, CSF pulsations, dissection through white matter tracts, and biomechanical effects of large skull defects. Bullet migration does not necessarily delay or prevent neurologic recovery.

Minimally Invasive Microsurgical Technique for Evacuation of Deep Intracerebral Hematomas.

Despite the lack of conclusive outcome data, surgical evacuation of large, symptomatic intracerebral hematomas (ICH) may be offered to patients on a case-by-case basis, aiming to prevent brain herniation, control intracranial pressure, relieve symptoms, and possibly facilitate or accelerate recovery.1-3 For deep ICH, minimally invasive techniques, which limit operative damage to healthy brain tissue, are generally preferred. Although new tube and endoscope-based techniques are currently being studied,4-7 those elaborate techniques are not widely available and often require special equipment and/or expensive disposable material. In this operative video (Video 1), we demonstrate a minimally invasive microsurgical approach for the evacuation of deep ICH, which relies on the use of careful preoperative planning, frameless stereotactic neuronavigation, and meticulous microsurgical technique. This technique involves small craniotomies, infracentimetric corticotomies, and physiologic subcortical white matter dissection, leading to very limited disruption of healthy brain tissue, akin to tube and endoscope-based procedures. We acknowledge that this technique or a modification thereof may currently be in use by other neurosurgeons in their practice.8 However, to the best of our knowledge, a step-by-step microsurgical video illustration of this technique has not been previously published. Although this technique can be broadly used by neurosurgeons, irrespective of the hospital setting, it would be particularly valuable in settings where expensive cutting-edge technology is not readily available.

Uterus didelphys and longitudinal vaginal septum coincident with an obstructive transverse vaginal septum.

A wide variety of Müllerian anomalies has been described in the literature. Various combinations of anomalies may coexist in a single subject. Precise identification of the various components of the anomaly is paramount in choosing and planning the appropriate conservative and surgical treatment. In this report, we present a rare case of combined vertical fusion and transverse canalization defects in a single subject. A review of the literature along with an overview of the pertinent embryologic processes and management concepts for such cases are presented.