Kuniaki Nakahara

Primary malignant lymphoma of the cranial vault

SummaryA 60-year-old woman presented with a subcutaneous mass on her scalp. Computed tomography (CT) showed a homogeneously enhanced mass of the parietal bone with both intra- and extra-calvarial extension and having destroyed the right parietal bone. The mass was hypointense on the T1-weighted magnetic resonance image, slightly hyperintense on the T2-weighted image and homogenously enhanced with Gd-DTPA. Bone scintigraphy showed prominent accumulation of radioisotopes in the scalp lesion. The tumour was removed, including the involved bone and dura mater. Histologic diagnosis was non-Hodgkin’s B-cell lymphoma, and tumour cells had infiltrated into the dura mater. The patient was treated with radiotherapy and chemotherapy. She returned to ordinary daily life and has been well without recurrence for 3 years. Although primary malignant lymphoma of the cranial vault is rare, it should be considered in the differential diagnosis when a mass is encountered in the cranial vault. We have found only fourteen such cases in the literature, and we review these cases.

A new transvenous approach to the carotid-cavernous sinus via the inferior petrooccipital vein

OBJECT The transvenous approach via the inferior petrosal sinus (IPS) is commonly used as the most appropriate for carotid-cavernous fistula (CCF) or cavernous sinus sampling. However, sometimes the IPS is not accessible because of anatomical problems and/or complications, therefore an alternative route is needed. In this paper, the authors present and discuss the utility of a transvenous approach to the cavernous sinus via the inferior petrooccipital vein. METHODS Four patients, 3 with dural CCFs and the other with Cushing disease, in whom endovascular surgical attempts failed using a conventional venous approach via the IPS, underwent a transvenous approach to the cavernous sinus via the inferior petrooccipital vein (IPOV). One dural CCF case had only cortical venous drainage, the second CCF also mainly drained into the cortical vein with slight inflow into the superior ophthalmic vein and inferior ophthalmic vein, and the third demonstrated drainage into the superior and inferior ophthalmic veins and IPOV. RESULTS In all cases, the cavernous sinus could be accessed successfully via this route and without complications. CONCLUSIONS The transvenous approach to the cavernous sinus via the IPOV should be considered as an alternative in cases when use of the IPS is precluded by an anatomical problem and there are no other suitable venous approach routes.

Linear fractures occult on skull radiographs: a pitfall at radiological screening for mild head injury.

BACKGROUND Skull radiography is widely used to screen for fractures in patients with mild head injury. However, the clear depiction of a fracture requires a gap in the skull separated by the fracture that is wide enough to allow the passage of x-rays. We studied atypical linear fractures that were not visualized clearly, because a specific anatomical configuration hampered the passage of x-rays. METHODS We retrospectively evaluated 278 patients with mild head injuries who had undergone routine skull radiography (anteroposterior and lateral views) and head computed tomography (CT). We found that some patients negative for linear fracture on skull radiographs were positive on bone window CT scans. RESULTS Of the 278 patients aged between 2 months and 66 years, 8 (2.9%) manifested a linear fracture on CT scans that presented as a cross section of the fracture oblique to the direction of the x-rays. Four of the 8 developed acute epidural hematoma; 2 of these patients underwent craniotomy. CONCLUSIONS Radiographic study returned false-negative results, because x-rays were absorbed by the double-layered skull along fractures whose cross section was oblique to the direction of the x-rays. The evaluation of head injury by radiography only may miss these fractures and their undetected presence may result in sequelae such as intracranial hematoma.

Dural Arteriovenous Fistulas in the Cavernous Sinus: Clinical Research and Treatment

Introduction. The purpose of this paper is to clarify the clinical course, with the dural carotid cavernous fistula (CCF), featuring a pallet of symptoms, paying special attention to radiological findings. Methods. Seventy-six consecutive patients with dural CCFs were investigated in detail, all of whom were defined by angiography. Results. The most common initial symptom was diplopia in 47 patients (62%) and the most frequently observed on arrival were type II, featuring cranial nerve palsies followed by the classical triad in 27, and then type I only with cranial nerve palsies. The time until admission with type I (mean: 6.7 W ± 6.0) was significantly shorter than that with type II (mean: 25.1 W ± 23.5). Branches from bilateral carotid arteries widely inflowing into bilateral carotid cavernous sinus were present in 30 (39%), 20 (26%) of which also demonstrated direct inflow into the intercavernous sinus. type I and II had more multiple venous drainage routes as compared with type III (classical triad only on arrival) and IV (initial development of the classical triad followed by cranial nerve palsy). Conclusion. In our series of dural CCF patients, the most common initial symptom was cranial nerve palsy, mostly featuring multiple venous drainage including cortical drainage. Such palsies should be added to the classical triad as indicative symptoms. Bilateral carotid arteries often inflow into cavernous and intercavernous sinuses, which should be taken into account in choice of therapeutic strategy.

Shortening of ventricular shunt catheter associated with cranial growth: effect of the frontal and parieto-occipital access route on long-term shunt patency.

ObjectThe authors present the difference of shortening the ventricular shunt catheter associated with growth of the cranium between the frontal and parieto-occipital access, a key for long patency of the shunt implanted in children.Materials and methodOur retrospective study included 28 children. In group A (n = 9), the catheter was inserted through a frontal burr hole and in group B (n = 19), through a parieto-occipital burr hole. To compare changes that occurred in the interval between the time of insertion and follow-up in the length of the ventricular catheter in the cranium and to assess displacement of the burr used for catheter entry.ResultsThe results show that ventricular catheter shortening and burr-hole displacement were more pronounced in group A.ConclusionsThis study documents that insertion of the ventricular catheter via the frontal route in children resulted in a higher incidence of shortening due to greater displacement of the burr hole adjacent to the coronal suture. Therefore, we recommend that the parieto-occipital route be used to maintain long-term shunt function.

Efficacy of endovascular surgery for ruptured aneurysms with vasospasm of the parent artery

Introduction In the presence of vasospasm it is recommended that surgical clipping for a ruptured aneurysm should be delayed until it disappears, but this may be associated with re-rupture of the aneurysm resulting in a poor outcome. The indications for endovascular coil embolization in such cases are discussed. Methods Since November 2002, endovascular coil embolization has been used in 18 consecutive patients with ruptured aneurysm with vasospasm of the parent artery ranging from 2 to 28 days (mean 9 days) after the initial subarachnoid hemorrhage. After successful obliteration of the aneurysm, a microcatheter preceded by a guidewire was introduced into the peripheral vessels with vasospasm of the A2 or M2 portions in order to release the vasospasm mechanically. Results Endovascular procedures were performed successfully in all but one of the cases (94%), resulting in complete occlusion in 14 of 17 patients and mild dilation of the vasospasm in all 17 patients without technical complications or re-rupture of the aneurysm. In the one case of failure because of a tortuous artery, surgical clipping was performed after disappearance of the vasospasm. Cerebral infarction occurred in four patients, but only one correlated with the distribution of catheterization and the neurological deficits had completely disappeared 3 months after the onset. Conclusion Catheterization of parent vessels in cases of vasospasm is safe for coiling and also mechanically releases vasospasm. Vasospasm of M2 and A2 segments can be treated with microcatheterization only.

Effects of Grapefruit Juice Consumption on Pharmacokinetics of Low Dose Simvastatin: Cross-over Study with a Review of the Literature

The effects of consumption of grapefruit juice on the pharmacokinetics of conventional low-dose simvastatin in Japan were investigated. In a randomized cross-over study with two phases, 10 healthy volunteers ingested grapefruit juice 400ml or water for 2 days. On day 3, a single 5mg dose of simvastatin was administered with grapefruit juice 200ml or water. Plasma concentrations of HMG-CoA reductase inhibitor were determined up to 8 h thereafter. Grapefruit juice increased the area under the plasma concentration-time curves from 0 to 8 h of total HMG-CoA reductase inhibitor 1.7- fold (p=0.002) and that of active HMG-CoA reductase inhibitor 1.7-fold (p=0.024). However, the peak concentrations (Cmax) and Tmax of total and active HMG-CoA reductase inhibitors were not significant influenced.Consumption of grapefruit juice with low-dose simvastatin thus resulted in mild increase of the plasma HMG-CoA reductase inhibitor, so that the pharmacokinetic interaction can be labeled as of weak CYP3A type.

Yokukansan improves distress of medical staff, and cognitive function and motivation in patients with destructive and aggressive behaviors after traumatic brain injury

Yokukansan (a Japanese Kampo medicine) has been reported to be safe and useful in treating behavioral and psychological symptoms in dementia patients. This study aimed to investigate the effects of yokukansan on destructive and aggressive behaviors in patients after traumatic brain injury.

Contrast stasis in large and giant internal carotid artery aneurysms as a good prognostic factor for endovascular coil embolization: retrospective study

Abstract Objective: Before treatment for large and giant aneurysms, we need some of the predictors to prognose a good result. In this retrospective study, we attempted to determine criteria such as angiographic signs to identify good candidates for effective endovascular surgery. Methods: This study involved 45 patients with large or giant aneurysms treated by endovascular embolization. For angiographic study, we delivered a bolus injection of contrast medium. All aneurysms were confirmed angiographically and the morphology was defined in detail before endovascular embolization. We divided the patients into two groups based on angiographic findings. Group A (n = 16) manifested stasis of the contrast medium in the aneurysm on venous phase. Group B (n = 29) exhibited other findings. We retrospectively evaluated the relationship between stasis of the contrast medium in the aneurysm and results of endovascular embolization. Results and Discussion: There was no significant difference between the two groups with respect to the size of the aneurysm. However, the neck/dome ratio (P = 0·04) and size of the neck (P = 0·003) were significantly different between groups A and B. The morphological outcome was better in group A than group B (P = 0·03). We demonstrate that contrast stasis is a good predictor of outcome in patients with large or giant aneurysms to consider the endovascular embolization. Hemodynamic studies on large patient populations may reveal other factors predictive of a good treatment outcome.

Lacunar skull deformity and hydrocephalus in infants with myelomeningocele: is lacunar skull deformity a predictor of hydrocephalus development?

ObjectsWe evaluated whether the presence of lacunar skull deformity (LSD) with myelomeningocele is a predictive factor for subsequent hydrocephalus development.Materials and methodsWe reviewed the clinical and radiological records of 18 infants with myelomeningocele, divided the patients into groups with (group A, n=9) and without (group B, n=9) ventriculomegaly at birth and assessed whether the presence of LSD was predictive of the necessity for ventriculoperitoneal shunt (VPS) placement.ResultsLSD was present in five group A patients. All nine group A patients underwent VPS placement. Among the group B patients, five had LSD; they underwent VPS placement. A significantly higher proportion of those with ventricle enlargement or LSD at birth required VPS placement (p=0.0001).ConclusionAdding to the ventriculomegaly at birth, the presence of LSD alerts to the necessity to monitor these infants closely to determine the necessity for VPS placement.