Protein tyrosine phosphatase receptor type Q in cerebrospinal fluid reflects ependymal cell dysfunction and is a potential biomarker for adult chronic hydrocephalus

BACKGROUND AND PURPOSE

Protein tyrosine phosphatase receptor type Q (PTPRQ) was extracted from the cerebrospinal fluid (CSF) of patients with probable idiopathic normal-pressure hydrocephalus (iNPH) by proteome analysis. We aimed to assess the feasibility of using CSF PTPRQ concentrations for the additional diagnostic criterion of iNPH in Japanese and Finnish populations.

METHODS

We compared PTPRQ concentrations among patients with probable iNPH and neurologically healthy individuals (normal control [NC] group), patients with normal-pressure hydrocephalus (NPH) of acquired and congenital/developmental aetiologies, patients with Alzheimer's disease and patients with Parkinson's disease in a Japanese analysis cohort. A corresponding iNPH group and NC group in a Finnish cohort was used for validation. Patients in the Finnish cohort who underwent biopsy were classified into two groups based on amyloid and/or tau deposition. We measured PTPRQ expression levels in autopsied brain specimens of iNPH patients and the NC group.

RESULTS

Cerebrospinal fluid PTPRQ concentrations in the patients with NPH of idiopathic, acquired and congenital/developmental aetiologies were significantly higher than those in the NC group and those with Parkinson's disease, but iNPH showed no significant differences when compared with those in the Alzheimer's disease group. For the patients with iNPH, the area under the receiver-operating characteristic curve was 0.860 in the Japanese iNPH and 0.849 in the Finnish iNPH cohorts. Immunostaining and in situ hybridization revealed PTPRQ expression in the ependymal cells and choroid plexus. It is highly possible that the elevated PTPRQ levels in the CSF are related to ependymal dysfunction from ventricular expansion.

CONCLUSIONS

Cerebrospinal fluid PTPRQ levels indicated the validity of this assay for auxiliary diagnosis of adult chronic hydrocephalus.

Microcatheter Originating Debris during Neuroendovascular Procedures: Mechanism of Dislodgement and Its Prevention

Embolic material dislodgement from microcatheters can potentially induce subclinical brain damage as evidenced by a delayed enhanced or other type of lesions. Some of the most frequently used microcatheters were investigated in vitro in different setups and combinations with different port insertions and rotating hemostatic valves. It was found that side port application increases injury to the catheter surface and debris dislodgement by conflicting with internal ledges in rotating hemostatic valves. This initial observation suggests the need for measures to remove the produced debris during such procedures.

Natural course of dissecting vertebrobasilar artery aneurysms without stroke

BACKGROUND AND PURPOSE

The natural history and therapeutic management of dissecting vertebrobasilar aneurysms without ischemic or hemorrhagic stroke (nonstroke dissecting vertebrobasilar aneurysms) are not well-established. We conservatively followed patients with nonstroke dissecting vertebrobasilar aneurysms and evaluated the factors related to clinical and morphologic deterioration.

MATERIALS AND METHODS

One hundred thirteen patients were enrolled and divided by clinical presentation at diagnosis: asymptomatic (group 1, n = 52), pain only (group 2, n = 56), and mass effect (group 3, n = 5). Patients were conservatively managed without intervention and antithrombotic therapy. Clinical outcomes and morphologic changes were analyzed.

RESULTS

A total of 113 patients who were diagnosed with nonstroke dissecting vertebrobasilar aneurysm had a mean follow-up of 2.9 years (range, 27 days to 8 years). Throughout that period, 1 patient in group 1 (1.9%) and 1 patient in group 2 (1.8%) showed clinical deterioration due to mass effect, and 1 patient in group 3 (20%) developed ischemic stroke followed by subarachnoid hemorrhage. Most patients (97.3%) were clinically unchanged. Three patients who had clinical deterioration showed aneurysm enlargement (P < .001). Aneurysms remained morphologically unchanged in 91 patients (80.5%). Aneurysm enlargement was seen in 5 patients (4.4%); risk of enlargement was significantly associated with either maximum diameter (hazard ratio = 1.30; 95% CI, 1.11-11.52; P = .001) or aneurysm ≥10 mm (hazard ratio = 18.0; 95% CI, 1.95-167; P = .011).

CONCLUSIONS

The natural course of these lesions suggests that acute intervention is not always required and close follow-up without antithrombotic therapy is reasonable. Patients with symptoms due to mass effect or aneurysms of >10 mm may require treatment.

Anterior communicating artery aneurysms: an overview

AComA aneurysms are most commonly found at the A1-A2 junction on the dominant side. The angle of the arteries at the bifurcation and the direction of blood flow are factors of hemodynamic stress in the apical region where these aneurysms often develop. They exist at the bifurcation of dominant A1, A2 and AComA and usually point in the direction away from the dominant A1. They are more prone to rupture and demonstrate the highest incidence of post-operative morbidity among anterior circulation aneurysms. Consideration of aneurysm morphology may be used to guide approaches in AComA aneurysms. Resection of the gyrus rectus in combination with a pterional approach was popularized by Yasargil and it became the standard for treatment or exposure of AComA aneurysms, although other skull base approaches are also widely used. Clip selection is of extreme importance and the preservation of blood flow to the perforators should be emphasized. Adequate dissection and exposure of the entire "H" complex prior to clipping is the key to a successful outcome. Separating the perforators from the neck or dome of the artery and preserving the parent vessel presents a substantial challenge to the surgeon when the aneurysm is behind the parent artery, making it difficult to achieve a good outcome.

[Principles of selection of the method of treating Itsenko-Cushing disease]

Various methods for therapy of Icenko-Cushing's disease: radiotherapeutic, surgical and medicinal were evaluated. A total of 184 patients were treated. The authors have been of opinion that therapeutic methods depended on function of the neuroendocrine system and adrenal cortex, e. g. reserpine used after gamma-therapy alone or in combination with unilateral adrenalectomy increased the efficacy of therapy and reduced the time of remission. Parlodel used alone or in combination with chloditan could be used in therapy of early forms of the disease in young patients. Transsphenoidal adenomectomy and proton beam therapy of the hypophysis were recommended in hypophysial adenomas. Proton beam therapy of the hypophysis was an effective method for therapy of patients with diffuse hyperplasia of the adrenal cortex and could be used in diffuse nodular hyperplasia of the adrenal cortex in combination with unilateral adrenalectomy.