Anatomical considerations and surgical manipulation of the rhomboid lip in microvascular decompression for hemifacial spasm.

BACKGROUND: In microvascular decompression (MVD) procedures for hemifacial spasm (HFS), surgeons often encounter a rhomboid lip which may obscure the root exit zone (REZ) of the facial nerve. This study aims to explore the anatomical variations of rhomboid lips and their surgical implications to improve safety and effectiveness in MVD surgeries. METHODS: A retrospective analysis was conducted on 111 patients treated for HFS between April 2021 and March 2023. The presence of a rhomboid lip was assessed through operative video records, and its characteristics, dissection methods, and impact on nerve decompression outcomes were further examined. Preoperative magnetic resonance imaging (MRI) scans were reviewed for detectability of the rhomboid lip. RESULTS: Rhomboid lips were identified in 33% of the patients undergoing MVD, with a higher prevalence in females and predominantly on the left side. Two distinct types of rhomboid lips were observed: membranous and cystic variations. The membranous type was noted for its smaller size and position ventral to the choroid plexus. In contrast, the cystic variation was distinguished by its larger size and a thin membrane that envelops the choroid plexus. Preoperative MRI successfully identified rhomboid lips in only 21% of the patients who were later confirmed to have them in the surgical procedures. Surgical approaches primarily involved incisions on the dorsal wall and along the glossopharyngeal nerve root, with only limited need for extensive dissection from lower cranial nerves. Immediate spasm relief was observed in 97% of the patients. One case exhibited a lower cranial nerve deficit accompanied by brainstem infarction, which was caused by the dissection from the lower cranial nerves. CONCLUSIONS: Recognizing the two variations of the rhomboid lip and understanding their anatomical structures are essential for reducing lower cranial nerve injuries and ensuring effective nerve decompression.

[Microsurgical Procedures of Microvascular Decompression for Trigeminal Neuralgia].

Microvascular decompression for trigeminal neuralgia was successfully performed following the secure surgical steps. The most crucial step involves creating a safe operative field in the dural opening. The petrotentorial junction should be identified without cerebellar retraction before proceeding to the deeper areas. Dissecting the petrosal vein and opening the horizontal fissure contributed to the expansion of the operative field. Bleeding often occurs from the dorsal cerebellar bridging vein and junction of the petrosal vein into the superior petrosal sinus. Transposition of the most common offenders, the superior and anterior inferior cerebellar arteries, is effectively achieved by dissecting both the proximal and distal sides of the neurovascular compression site. Teflon should be placed at a sufficient distance to prevent contact with the nerve, which can lead to recurrence. Treating vertebrobasilar artery-related cases is challenging and involves the risk of cranial nerve injuries. Multiple offending vessels are commonly involved. In such cases, it is essential to be aware of the course of the trochlear and abducens nerves during decompression. Applying the most effective and least risky maneuver is necessary for treating cases involving the vertebrobasilar artery.

The Kumagai Method Utilizing the Pigeon Bottle Feeder with a Long Nipple: A Descriptive Study for the Development of Feeding Techniques for Children with Cleft Lip and/or Palate.

We aimed to identify the steps involved in the Kumagai method-an experimental nursing procedure to feed children with cleft lip and/or palate, using a feeder with a long nipple. We conducted a descriptive study, enrolling five specialist nurses who have mastered the Kumagai method. Their approaches were examined using structured interviews. Moreover, the participants were asked to perform the sequence of actions involved in this method while describing each step. Therefore, we were able to explore the Kumagai method in depth and step-by-step, including the following aspects: correct infant posture; correct feeding bottle holding position; nipple insertion into the child's mouth; and feeding process initiation, maintenance, and termination. Each step comprises several clinically relevant aspects aimed at encouraging the infant to suck with a closed mouth and stimulating chokubo-zui, i.e., simulation of the natural tongue movement during breastfeeding in children without a cleft palate. In conclusion, when performed correctly, the Kumagai method improves feeding efficiency in children with cleft lip and/or palate. Feeders with long nipples are rarely used in clinical practice; the Kumagai method might popularize their use, thereby improving the management of feeding practices for children with cleft lip and/or palate.

Identification and Safety Assessment of Enterococcus casseliflavus KB1733 Isolated from Traditional Japanese Pickle Based on Whole-Genome Sequencing Analysis and Preclinical Toxicity Studies.

The present study involves the precise identification and safety evaluation of Enterococcus casseliflavus KB1733, previously identified using 16S rRNA analysis, through whole-genome sequencing, phenotypic analysis, and preclinical toxicity studies. Analyses based on the genome sequencing data confirm the identity of KB1733 as E. casseliflavus and show that the genes related to vancomycin resistance are only present on the chromosome, while no virulence factor genes are present on the chromosome or plasmid. Phenotypic analyses of antibiotic resistance and hemolytic activity also indicated no safety concerns. A bacterial reverse mutation test showed there was no increase in revertant colonies of heat-killed KB1733. An acute toxicity test employing heat-killed KB1733 at a dose of 2000 mg/kg body weight in rats resulted in no deaths and no weight gain or other abnormalities in the general condition of the animals, with renal depression foci and renal cysts only occurring at the same frequency as in the control. Taking the background data into consideration, the effects on the kidneys observed in the current study were not caused by KB1733. Our findings suggest that KB1733 is non-pathogenic to humans/animals, although further studies involving repeated oral toxicity tests and/or clinical tests are required.