Beyond uncal herniation: An updated diagnostic reappraisal of ipsilateral hemiparesis and the Kernohan-Woltman notch phenomenon.

PURPOSE: This works comprehensively analyses a modern cohort of patients with ipsilateral hemiparesis (IH) and discusses the pathophysiological theories elaborated to explain this paradoxical neurological sign according to the findings from contemporary neuroimaging and neurophysiological techniques. METHODS: A descriptive analysis of the epidemiological, clinical, neuroradiological, neurophysiological, and outcome data in a series of 102 case reports of IH published on since the introduction of CT/MRI diagnostic methods (years 1977-2021) was performed. RESULTS: IH mostly developed acutely (75.8%) after traumatic brain injury (50%), as a consequence of the encephalic distortions exerted by an intracranial haemorrhage eventually causing contralateral peduncle compression. Sixty-one patients developed a structural lesion involving the contralateral cerebral peduncle (SLCP) demonstrated by modern imaging tools. This SLCP showed certain variability in its morphology and topography, but it seems pathologically consistent with the lesion originally described in 1929 by Kernohan & Woltman. The study of motor evoked potentials was seldom employed for the diagnosis of IH. Most patients underwent surgical decompression, and a 69.1% experienced some improvement of the motor deficit. CONCLUSIONS: Modern diagnostic methods support that most cases in the present series developed IH following the KWNP model. The SLCP is presumably the consequence of either compression or contusion of the cerebral peduncle against the tentorial border, although focal arterial ischemia may also play a contributing role. Some improvement of the motor deficit should be expected even in the presence of a SLCP, provided the axons of the CST were not completely severed.

Clinical features, diagnosis and therapy of pituicytoma: an update.

BACKGROUND: Pituicytomas (PTs) are extremely rare, low-grade glial tumors closely related to the neurohypophyseal axis. Definite conclusions concerning the optimal diagnostic and therapeutic approach to these neoplasms are lacking to date, as most of this information has been presented as case reports. METHODS: Retrospective review of case reports published in the scientific literature to date, including a new illustrative example treated in our department. RESULTS: 116 cases were collected. PTs had a higher prevalence in the fifth and sixth decades of life, with a slight male predominance. Main symptoms, which tended to be progressive, included visual field defects and pituitary-hypothalamic dysfunction. Radiologically, PTs were found anywhere along the hypothalamic-pituitary axis mimicking other, more frequent tumors growing in this anatomical region. Surgical treatment included both transcranial or transsphenoidal approaches, and resulted in gross total resection and morbidity rates of 46.8 and 59%, respectively; the latter essentially consisted in anterior and posterior pituitary dysfunction, with limited impact on daily quality of life. CONCLUSIONS: Due to both low frequency and the absence of pathognomonic clinical and/or radiological features, formulating a suspicion diagnosis of PT represents a considerable challenge even for experienced professionals. The indication for treatment should be made on an individual basis, but it is inescapable in the presence of a visual field defect. The surgical approach has to be tailored according to the topography of the tumor and preoperative symptoms; the greatest challenges in accomplishing a gross total removal are represented by the degree of adherence and vascularization of the PT.

Kernohan-Woltman notch phenomenon: an exceptional neurological picture?

INTRODUCTION: Ipsilateral hemiparesis (IH) can be defined as a paradoxical dysfunction of the first motor neuron involving the extremities on the opposite side to that expected, given the location of the triggering intracranial pathology. Compression of the corticospinal tract (CSt) along its course through the contralateral cerebral peduncle against the free edge of the tentorium, known as the Kernohan-Woltman notch phenomenon (KWNP), represents the main cause of IH. METHODS: This retrospective study analyses a series of 12 patients diagnosed with IH secondary to KWNP treated at our institution, including a descriptive study of epidemiological, clinical, radiological, neurophysiological, and prognostic variables. RESULTS: In 75% of the cases, symptoms had an acute or subacute onset. Initial imaging studies showed signs of significant mass effect in half of the patients, whereas magnetic resonance imaging (MRI) identified a structural lesion in the contralateral cerebral peduncle in two thirds of them. Impairment of the motor evoked potentials (MEP) was verified in 4 patients. During follow-up 7 patients experienced improvement in motor activity, and near half of the cases were classified in the first three categories of the modified Rankin scale. CONCLUSIONS: In contrast to prior historical series, most of our patients developed a KWNP secondary to a traumatic mechanism. MRI represents the optimal method to identify both the classic cerebral peduncle notch and the underlying structural lesion of the CSt. The use of MEP can help to establish the diagnosis, especially in those cases lacking definite radiological findings.

[Multimodal CT in the diagnostic workup of stroke]. / TC multimodal en el diagnóstico del código ictus.

Stroke results in significant morbidity and mortality. Recent years have seen a revolution in the diagnosis and treatment of stroke, with advances in diagnostic imaging and improvements in early and specific treatment. Multimodal CT (unenhanced CT, perfusion CT, and CT angiography) is widely available, fast, and efficacious, all of which give it a key role in the early diagnosis of stroke and in the selection of patients who will benefit from thrombolytic treatment. Unenhanced CT is useful for ruling out hemorrhage or lesions that simulate stroke and for evaluating the presence of early signs. Perfusion CT enables us to know the presence and extension of infarcted ischemic tissue (irrecoverable) and of penumbra (tissue at risk that is potentially recoverable), thus ensuring more appropriate selection of candidates for treatment. Finally, CT angiography makes it possible to evaluate the intra- and extra-cranial circulation, to know the vascular alteration that originated the stroke, and to guide treatment (intra-arterial or mechanical thrombolysis).

Postoperative management of patients with pituitary tumors submitted to pituitary surgery. Experience of a Spanish Pituitary Tumor Center of Excellence.

There is a lack of evidence on timing, frequency, and duration of postoperative endocrine, radiologic, and ophthalmologic assessments that should be performed after pituitary surgery (PS). However, it is known that careful optimization of treatment and follow-up strategies as well as a multidisciplinary approach may have a significant impact on long-term outcomes, improving surgical results, minimize complications and facilitate their correct treatment if occurring, and optimize the hormonal, ophthalmological, and radiological reassessment throughout the follow-up. Considering that there are no specific guidelines on the postoperative management of patients with pituitary tumors (PT), we present our protocol for the postoperative management of patients with PT. It has been elaborated by the multidisciplinary team of a Spanish Pituitary Tumor Center of Excellence (PTCE) that includes at least one neurosurgeon, ENT, neuroradiologist, neuro-ophthalmologist, endocrine pathologist and endocrinologist specialized in pituitary diseases. We elaborated this guideline with the aim of sharing our experience with other centers involved in the management of PT thereby facilitating the postoperative management of patients submitted to PS.

Spinal extradural angiolipomas: 7 new cases and review of the literature. / Angiolipomas espinales epidurales: presentación de 7 casos y revisión de la literatura.

INTRODUCTION: We present our experience with the diagnosis and treatment of spinal angiolipomas (SAL). METHODS: We used our database of surgical patients to gather epidemiological, clinical, diagnostic, treatment, and follow-up data from confirmed cases of SAL. Patients' functional status was evaluated using the modified Japanese Orthopaedic Association (mJOA) score for thoracic myelopathy. RESULTS: We included 7 patients with ages ranging between 42 and 63 years; 4 were women. Lesions in all patients were located in the thoracic epidural space; in 2 cases, lesions extended outside the spinal canal. The most frequent form of presentation was pain combined with progressive myelopathy; patients scored 5 to 9 points on the mJOA scale. Radiological findings varied; this variability clearly depended on the proportion of tumour components (cellular variant in one case, predominantly angiomatous in another, and myxoid in yet another case). Four cases displayed radiological signs of bone involvement. Surgery resulted in excellent mJOA scores except in one case (mJOA score of 10); no recurrences were detected during follow-up (periods ranging from 1 to 5 years). CONCLUSIONS: Extradural SAL can present with highly variable radiological and clinical features. Surgery must be tailored to each individual situation according to tumour extension; in some cases, it may include spinal reconstruction. Surgery results in excellent outcomes regardless of preoperative functional status and it is associated with low recurrence rates, even in case of incomplete resection.