Predictive Value of Total Small-Vessel Disease Score for Recurrent Stroke in Patients Undergoing Maintenance Hemodialysis.

OBJECTIVES: We sought to examine the validity of the total small-vessel disease (SVD) score in patients receiving maintenance hemodialysis by investigating its predictive value for recurrent stroke. METHODS: We identified 159 patients who showed acute ischemic stroke while receiving maintenance hemodialysis at our institute between January 1, 2008, and December 31, 2020; retrospectively calculated the total SVD score for each patient; and extracted data on demographic factors and comorbidities that could potentially affect recurrent stroke. Death was thought to be a potential competing risk for recurrent stroke because the perceived risk of death was considerably higher than the risk of recurrent stroke in these patients. Thus, we investigated the association between the total SVD score and recurrent stroke by analyzing the competing risk of non-stroke death. RESULTS: The median (interquartile range) age was 72 (62-80) years. A total of 38 (23.9%) recurrent strokes occurred, and 69 (43.4%) patients died during the 505 patient-year follow-up study. The estimated cumulative incidence of recurrent stroke at five years was 13.3%, 13.4%, 24.1%, 50%, and 60% for scores of 0 to 4, respectively, and the hazard ratio (HR), adjusted for variables that had been reported to be risk factors of stroke in dialysis patients, per unit increase in the score was 1.72 (95% CI, 1.34-2.21; p<0.001). CONCLUSION: A higher total SVD score was associated with an increased risk of recurrent stroke in patients undergoing maintenance hemodialysis.

The Effectiveness of the Stereotactic Burr Hole Technique for Deep Brain Stimulation.

Deep brain stimulation (DBS) is performed by burr hole surgery. In microelectrode recording by multi-channel parallel probe, because all microelectrodes do not always fit in the burr hole, additional drilling to enlarge the hole is occasionally required, which is time consuming and more invasive. We report a stereotactic burr hole technique to avoid additional drilling, and the efficacy of this novel technique compared with the conventional procedure. Ten patients (20 burr holes) that received DBS were retrospectively analyzed (5 in the conventional burr hole group and 5 in the stereotactic burr hole group). In the stereotactic burr hole technique, the combination of the instrument stop slide of a Leksell frame and the Midas Rex perforator with a 14-mm perforator bit was attached to the instrument carrier slide of the arc in order to trephine under stereoguidance. The efficacy of this technique was assessed by the number of additional drillings. Factors associated with additional drilling were investigated including the angle and skull thickness around the entry points. Four of the 10 burr holes required additional drilling in the conventional burr hole group, whereas no additional drilling was required in the stereotactic burr hole group (p = 0.043). The thicknesses in the additional drilling group were 10.9 ± 0.9 mm compared to 9.1 ± 1.2 mm (p = 0.029) in the non-additional drilling group. There were no differences in the angles between the two groups. The stereotactic burr hole technique contributes to safe and exact DBS, particularly in patients with thick skulls.

Spinal cord stimulation for intractable pain evaluated by a collision study using somatosensory evoked potentials: a preliminary report.

OBJECTIVE: Appropriate stimulation of the dorsal column is required in order to achieve optimal control over pain by way of spinal cord stimulation (SCS). In this study, we objectively evaluated changes in somatosensory evoked potentials (SEPs) during a collision test in order to investigate whether paresthetic sensation or amount of pain reduction was correlated with the degree of dorsal column stimulation. MATERIALS AND METHODS: We studied 12 patients with intractable pain who underwent permanent SCS implantation. SEP collision was examined while recording the cortical SEP components elicited by posterior tibial nerve stimulation. A positive collision effect was observed when the SEP amplitude was clearly reduced by the SCS. RESULTS: Based on the SEP collision findings, the effects of SCS were classified into four patterns: positive collision with pain reduction (Type 1), positive collision without pain reduction (Type 2), negative collision with pain reduction (Type 3), and negative collision without pain reduction (Type 4). Type 1 was observed for well-known diseases in which SCS was very effective, whereas Type 2 was seen in poor candidates for dorsal column stimulation. Patients with poststroke pain exhibited various patterns including types 1, 2, and 3. One patient showed Type 4 patterning, and we recommended further SCS trials before the abandonment of SCS therapy for this patient. CONCLUSIONS: We show that SEP collision is useful for evaluating the degree of dorsal column stimulation needed as well as in considering factors related to differences between responders and nonresponders to SCS therapy.

Development of interstitial pneumonia in a patient with rheumatoid arthritis induced by isoniazid for tuberculosis chemoprophylaxis.

Here, we report a 56-year-old patient with rheumatoid arthritis (RA) who had been treated with methotrexate and sulfuasalazine, but the disease activity remained high. Therefore, we planned TNF-blocker treatment for this patient. A tuberculin skin test was positive, we started anti-tuberculosis (TB) chemoprophylaxis with isoniazid (INH). However, liver dysfunction was appeared after 2 weeks from the start of INH. Therefore, we discontinued INH transiently and tried the desensitization of INH. However, interstitial pneumonia was developed 2 weeks after the re-start of INH, we decided to stop the INH prophylaxis. Interstitial pneumonia was improved by corticosteroid treatments. This case report shows that INH-induced IP can be occurred during the course of anti-TB chemoprophylaxis in patients with RA.

[Hypertensive intracerebral hemorrhage in isolated islands in Nagasaki Prefecture: a remote teleradiology and helicopter transportation system].

Hypertensive intracerebral hemorrhage (HICH) causes significant morbidity and mortality. The time required to transport the patients to a specialized hospital can influence the prognosis. In the isolated islands in Nagasaki prefecture, there is no medical institution which can offer emergent neurosurgical intervention. We reviewed the cases of HICH in this region from January 2006 to September 2010, who were transferred to Nagasaki Medical Center by a helicopter after consultation via teleradiology. Eighty four cases (23%) were transferred via helicopter to our institution from isolated islands. In three of them (4%), re-hemorrhage was demonstrated on computed tomography after helicopter transportation, and one of three had been administered an anti-coagulant agent. Only one case (1%) has deteriorated during helicopter transportation because of acute obstructive hydrocephalus. The outcome at discharge was as follows: modified Rankin Scale (mRS) I: 3 cases (4%), II: 5 cases (6%), III: 3 cases (4%), IV: 30 cases (36%), V: 31 cases (37%), VI: 12 cases (14%), 43 cases (51%) showed poor outcome (mRS V, VI). For medical management in isolated islands, a remote teleradiology system is indispensable to decide a strategy of treatment rapidly, and a helicopter transportation system is very useful in cases requiring emergent neurosurgical intervention, particular in cases of impending cerebral herniation or acute hydrocephalus. However, we may need to expand logistical supporting hospitals or secure other transportation facilities because many of the patients with poor outcome can not return to their home islands.

[Trigeminal neuralgia in an elderly patient associated with a variant of persistent primitive trigeminal artery].

An 86-year-old woman presented with a 10-year history of right paroxysmal facial pain. The trigger zone was the right maxilla. Magnetic resonance (MR) angiography and MR cisternography sourse images showed an aberrant artery originating from the right internal carotid artery anastomosed to the anterior inferior cerebellar artery territory (AICA) of the cerebellum, and it was closed at the root entry zone of trigeminal nerve. The patient underwent microvascular decompression (MVD), and her pain resolved after the operation. Most of the offending vessels that cause trigeminal neuralgia are the superior cerebellar artery (75-80%) and AICA. Although persistent primitive trigeminal artery (PTA) is the most common type of persistent carotid-basilar anastomosis, trigeminal neuralgia associated with PTA or a PTA variant is very rare, and particularly, a PTA variant is an uncommon, anomalous, intracranial vessel. It is necessary to inspect MR imaging scans carefully prior to MVD surgery because they are frequently associated with intracranial aneurysms. During surgery, we must be careful not to injure the perforating arteries from the PTA variant. MVD for trigeminal neuralgia in elderly patients is effective if the patients can have a tolerate general anesthesia. However, when we plan surgery for elderly patients, we must take care that it does not to lead to unexpected complications.