Comparison of joint degeneration and pain in male and female mice in DMM model of osteoarthritis.

OBJECTIVE: While the prevalence of radiographic and symptomatic osteoarthritis (OA) is higher in women, male mice are more frequently used in animal experiments to explore its pathogenesis or drug efficacy. In this study, we examined whether sexual dimorphism affects pain and joint degeneration in destabilization of the medial meniscus (DMM) mouse model. METHODS: DMM or sham surgery was performed on the knee of male and female C57BL/6 mice. Joint damage was assessed by safranin O staining and scored using the Osteoarthritis Research Society International (OARSI) scoring system. Von Frey hair, incapacitance, and rotarod tests were conducted to measure joint pain. The analgesic effect of capsazepine (CPZ), a TRPV1 antagonist, was compared between male and female mice. RESULTS: Histology and OARSI scoring analysis showed that cartilage degeneration developed, and progressed in both male and female DMM groups, however, damage was less severe in females at the late stage of OA. Pain behavior, as measured by mechanical allodynia, was displayed for longer in male DMM mice compared to females. Incapacitance data showed that CPZ significantly reduced DMM-induced pain in male mice but not in female mice. Immunofluorescence microscopy analysis demonstrated that DMM surgery increased the expression of TRPV1 in both female and male dorsal root ganglion (DRG). Injection of CPZ significantly suppressed TRPV1 expression in the DRG of male mice only. CONCLUSION: Joint damage develops comparably in both female and male mice after DMM although it progresses less in females. There was a subtle sex difference in pain behaviors and analgesic efficacy of a TRPV1 antagonist, which was accompanied by a differential regulation of TPRV1.

Risk factors for Korean women to develop an isthmocele after a cesarean section.

BACKGROUND: The increase in number of cesarean section (CS) operations has resulted in an increase in cases of isthmocele development. The objective of this study is to determine the risk factors for isthmocele development after CS. METHODS: Isthmocele measurements were taken for 404 women with a history of at least one low transverse CS. The following potential risk factors were investigated: patient's age at CS, cause of CS, weeks of gestation at CS, premature rupture of membrane (PROM), phase of labor, type suture (single/double layer), operation time, uterine flexion (anteversion/retroversion), and blood transfusion during operation. A transvaginal ultrasound was carried out to examine the isthmocele in the uterus after CS, including the shape of the isthmocele, residual myometrial thickness, depth and width of isthmocele, cervical thickness, location of the isthmocele, and clinical characteristics. RESULTS: In our study population, the isthmocele had a prevalence of 73.8%. Most isthmocele had a triangular (65.4%) or semicircular shape (10.4%). The presence of an isthmocele was significantly associated with repeat CS, premature rupture of membrane (PROM), short operation time, and extent of cervix dilatation at CS. The risk of isthmocele was low in women who had placenta previa totalis (PPT), twin, a long operation time, or a transfusion during the operation. CONCLUSIONS: In our study, isthmocele development was significantly associated with repeat CS, PROM, a short operation time, and the extent of cervix dilatation at CS. Therefore, PROM prevention and a more careful uterine closure are needed to reduce the risk of developing an isthmocele after CS.

FANCA and FANCG are the major Fanconi anemia genes in the Korean population.

Fanconi anemia (FA) is a rare disorder characterized by physical abnormalities, bone marrow failure (BMF), increased risk of malignancies, and cellular hypersensitivity to DNA cross-linking agents. This study evaluated the genetic alterations in three major Fanconi genes (FANCA, FANCC, and FANCG) in 30 FA patients using multiplex ligation-dependent probe amplification and direct sequencing. Thirteen BMF patients were genetically classified as FA-A (n = 6, 46%) and FA-G (n = 7, 54%). Four common founder mutations were identified and included two FANCA mutations (c.2546delC and c.3720_3724delAAACA) and two FANCG mutations (c.307+1G>C and c.1066C>T), which had previously been commonly observed in a Japanese FA population. We also detected four novel deleterious mutations: c.2778+1G>C and c.3627-1G>A of FANCA, and c.1589_1591delATA and c.1761-1G>A of FANCG. This study shows that mutations in FANCA and FANCG are common in Korean FA patients and the existence of four common founder mutations in an East Asian FA population. Mutation screening workflow that includes these common mutations may be useful in the creation of an international database, and to better understand the ethnic characteristics of FA.

A novel COL7A1 mutation in a Korean patient with Hallopeau-Siemens recessive dystrophic epidermolysis bullosa.

Dystrophic epidermolysis bullosa (DEB) is an inherited skin fragility disorder that presents various clinical manifestations. DEB is characterized by separation of sublamina densa tissue and abnormalities in the anchoring fibrils that result from mutations in COL7A1 and subsequent defects in type VII collagen. A 16-month-old boy was diagnosed with Hallopeau-Siemens recessive DEB on the basis of typical skin lesions composed of multiple blisters with moderately healed erosions, scarring on trauma-exposed body sites, including hands and feet, pseudosyndactyly and flexion contractures of the toes, and severely dystrophic nails on the right hand. Genomic DNA from the patient and parents were subjected to direct sequencing for the COL7A1 gene. Two heterozygous mutations were detected in the affected child; one novel mutation designated c.4232delC in exon 38 and a single-base substitution (c.6573+1G>C) in intron 81. Deletion of a single cytosine at codon 1411 within exon 38 had produced a frameshift mutation that created a stop codon at codon 1427 (p.Pro1411Leufs*17). This intronic base substitution had led to aberrant splicing and a premature termination codon. This is a novel mutation of COL7A1 associated with DEB in a Korean patient, adding to the range of COL7A1 mutations related to DEB.

Postoperative Doppler Ultrasonography in Liver Transplantation.

BACKGROUND: Doppler ultrasonography plays an important role in the postoperative management of liver transplantation. We present our initial experiences evaluating liver transplants with the use of postoperative Doppler sonography. METHODS: In our hospital, we performed 20 liver transplantations from July 2014 to October 2016. Among 20 patients, we performed 15 deceased-donor liver transplantations (DDLTs) and 5 living-donor liver transplantations (LDLTs). For deceased donors, inferior vena cava anastomoses were performed with the use of the piggyback technique, and for living donors, modified right grafts were used with middle hepatic vein reconstruction by Dacron graft. In the intensive care unit, we performed Doppler ultrasound at least once a day and at every clinical need. We checked hepatic blood flow by means of Doppler ultrasound. RESULTS: Eighteen patients underwent Doppler ultrasonography once a day up to postoperative day 6. Of the patients who received LDLT, 2 patients underwent Doppler ultrasonography twice a day because the operator was concerned about the hepatic artery anastomosis. Findings on Doppler ultrasound showed no abnormal wave form in hepatic artery, portal vein and hepatic veins. No patient had abnormal findings on angiographic computerized tomography. There was 1 graft failure in 20 recipients. The graft failure was primary nonfunction, and retransplantation was done. During the hospitalizations, there were no vascular complications. CONCLUSIONS: Doppler ultrasonography can be used to evaluate postoperative vascular complications in liver transplant patients. When the operator checks postoperative Doppler ultrasonography, it is possible to differentiate between patients, and it may help to detect the vascular complications earlier.

Runx3 plays a critical role in restriction-point and defense against cellular transformation.

The restriction (R)-point decision is fundamental to normal differentiation and the G1-S transition, and the decision-making machinery is perturbed in nearly all cancer cells. The mechanisms underlying the cellular context-dependent R-point decision remain poorly understood. We found that the R-point was dysregulated in Runx3-/-mouse embryonic fibroblasts (MEFs), which formed tumors in nude mice. Ectopic expression of Runx3 restored the R-point and abolished the tumorigenicity of Runx3-/-MEFs and K-Ras-activated Runx3-/-MEFs (Runx3-/-;K-RasG12D/+). During the R-point, Runx3 transiently formed a complex with pRb and Brd2 and induced Cdkn1a (p21Waf1/Cip1/Sdi1; p21), a key regulator of the R-point transition. Cyclin D-CDK4/6 promoted dissociation of the pRb-Runx3-Brd2 complex, thus turning off p21 expression. However, cells harboring oncogenic K-Ras maintained the pRb-Runx3-Brd2 complex and p21 expression even after introduction of Cyclin D1. Thus, Runx3 plays a critical role in R-point regulation and defense against cellular transformation.

High-resolution profiling of histone h3 lysine 36 trimethylation in metastatic renal cell carcinoma.

Mutations in SETD2, a histone H3 lysine trimethyltransferase, have been identified in clear cell renal cell carcinoma (ccRCC); however it is unclear if loss of SETD2 function alters the genomic distribution of histone 3 lysine 36 trimethylation (H3K36me3) in ccRCC. Furthermore, published epigenomic profiles are not specific to H3K36me3 or metastatic tumors. To determine if progressive SETD2 and H3K36me3 dysregulation occurs in metastatic tumors, H3K36me3, SETD2 copy number (CN) or SETD2 mRNA abundance was assessed in two independent cohorts: metastatic ccRCC (n=71) and the Cancer Genome Atlas Kidney Renal Clear Cell Carcinoma data set (n=413). Although SETD2 CN loss occurs with high frequency (>90%), H3K36me3 is not significantly impacted by monoallelic loss of SETD2. H3K36me3-positive nuclei were reduced an average of ~20% in primary ccRCC (90% positive nuclei in uninvolved vs 70% positive nuclei in ccRCC) and reduced by ~60% in metastases (90% positive in uninvolved kidney vs 30% positive in metastases) (P<0.001). To define a kidney-specific H3K36me3 profile, we generated genome-wide H3K36me3 profiles from four cytoreductive nephrectomies and SETD2 isogenic renal cell carcinoma (RCC) cell lines using chromatin immunoprecipitation coupled with high-throughput DNA sequencing and RNA sequencing. SETD2 loss of methyltransferase activity leads to regional alterations of H3K36me3 associated with aberrant RNA splicing in a SETD2 mutant RCC and SETD2 knockout cell line. These data suggest that during progression of ccRCC, a decline in H3K36me3 is observed in distant metastases, and regional H3K36me3 alterations influence alternative splicing in ccRCC.

Cloning of mouse sepiapterin reductase gene and characterization of its promoter region.

We have isolated and characterized approximately 5 kb mouse sepiapterin reductase gene (Spr) and a highly homologous pseudogene (Sprp). The authentic Spr gene is present as a single copy in the mouse genome and is composed of three exons containing the entire coding region. The primer extension experiment located the transcription initiation site in a putative pyrimidine-rich Inr element. The promoter region of the Spr gene is embedded within a CpG island. It was shown that the promoter region is devoid of distinctive TATA and CAAT boxes. Transient transfection of a series of 5' deletion derivatives of the Spr promoter showed the sequence between -83 and -51 to be essential for promoter activity. The pseudogene Sprp lacks promoter region and exon 3.

Angiocentric lymphoma of the head and neck: patterns of systemic failure after radiation treatment.

PURPOSE: To investigate the patterns of systemic failure and the clinical outcome in patients with angiocentric lymphoma of the head and neck who were treated with radiation alone, and to discuss the optimal mode of treatment for these patients. PATIENTS AND METHODS: We reviewed the records of 92 patients with stage I or II angiocentric lymphoma who were treated at Yonsei Cancer Center between 1976 and 1994. All patients were treated with involved-field irradiation. Radiation doses ranged from 40 to 60 Gy (median dose, 50.4 Gy). Treatment response, patterns of treatment failure including systemic failure, and clinical outcome after radiation treatment were analyzed. RESULTS: The most frequently involved site was the nasal cavity, either alone or in conjunction with other sites. In 16 patients (17.4%), angiocentric lymphoma was accompanied by cervical lymphadenopathy. Disease was classified as stage I in 62 patients (67.4%) and stage II in 30 patients (32.6%). After completion of radiation treatment, 61 patients (66.3%) achieved a complete response and 16 (17.4%) a partial response. Half of the patients (50.0%) ultimately experienced local recurrence with or without other components of failure, whereas regional failure was relatively uncommon (10.9%). Systemic failure occurred in 25.0% of patients during follow-up. Six patients had histologic findings identical to those at the time of the original disease (group I), whereas four patients exhibited morphologic features of frank lymphomas (group II). The majority of patients with systemic relapse had the predilection sites for widespread extranodal involvement, such as the skin, brain, lung, gastrointestinal tract, or testes. In addition, seven patients died from various medical illnesses or immunologic disorders, including hemophagocytic syndrome and second primary cancers (group III). After a median follow-up of 56 months, the overall survival and disease-free survival rates for all patients were 40.1% and 37.8%, respectively. All patients except one with systemic failure died within 1 year. CONCLUSION: Treatment with radiation alone had suboptimal results, partly because of the occurrence of a variety of systemic failure with diverse clinicopathologic features. Given the frequent occurrence of systemic failure after radiation treatment, we believe that the multimodality treatment approach containing more effective chemotherapeutic agents should be incorporated in the treatment of angiocentric lymphoma confined to the head and neck.

Extensive curettage using a high-speed burr versus dehydrated alcohol instillation for the treatment of enchondroma of the hand.

The purpose of this retrospective study was to compare the clinical and radiological outcomes of patients treated with different adjuvant methods after curettage for enchondromas of the hand. Sixty-two patients with enchondroma were treated with high-speed burring (29 patients) or alcohol instillation (33 patients) after curettage. The mean follow-up was 40.8 months. No significant differences in the visual analogue scale, Disabilities of the Arm, Shoulder, and Hand scores, total range of active motion, grip strength, and complete healing time were observed between the groups. The distribution of the results of the formula by Wilhelm and Feldmeier were not significantly different between the groups. No surgery-related complications, postoperative pathological fractures, or recurrence was found in either group. For the treatment of enchondroma in the metacarpal and proximal phalanx, alcohol instillation immediately after curettage was as effective as extensive curettage using a high-speed burr.

A novel antimicrobial peptide from the loach, Misgurnus anguillicaudatus.

A novel antimicrobial peptide, named misgurin, was isolated and characterized from the loach (mudfish), Misgurnus anguillicaudatus. The 21-amino-acid peptide with a molecular mass of 2502 Da was purified to homogeneity using a heparin-affinity column and C18 reverse-phase and gel-permeation high-performance liquid chromatography. The complete amino acid sequence of misgurin, which was determined by an automated amino acid sequencer, was Arg-Gln-Arg-Val-Glu-Glu-Leu-Ser-Lys-Phe-Ser-Lys-Lys-Gly-Ala-Ala-Ala-Arg- Arg-Arg-Lys. Misgurin is a strongly basic peptide which has 5 arginine and 4 lysine residues. Comparison of the amino acid sequence with those of other known antimicrobial peptides revealed that misgurin was a novel antimicrobial peptide. Misgurin showed a strong antimicrobial activity in vitro against a broad spectrum of microorganisms without significant hemolytic activity and was about 6 times more potent than magainin 2. Scanning electron microscopy confirmed that the peptide caused damage to the cell membrane by a pore-forming mechanism similar to that of magainin 2. This damage occurred at the minimal inhibition concentration (MIC), but at higher concentration than MIC it lysed the cell.

Parasin I, an antimicrobial peptide derived from histone H2A in the catfish, Parasilurus asotus.

In response to epidermal injury, Parasilurus asotus, a catfish, secreted a strong antimicrobial peptide into the epithelial mucosal layer. The molecular mass of the antimicrobial peptide, named parasin I, was 2000.4 Da, as determined by matrix-associated laser desorption ionization mass spectrometry. The complete amino acid sequence of parasin I, which was determined by automated Edman degradation, was Lys-Gly-Arg-Gly-Lys-Gln-Gly-Gly-Lys-Val-Arg-Ala-Lys-Ala-Lys-Thr-Arg-Ser- Ser. Eighteen of the 19 residues in parasin I were identical to the N-terminal of buforin I, a 39-residue antimicrobial peptide derived from the N-terminal of toad histone H2A [Kim et al. (1996) Biochem. Biophys. Res. Commun. 229, 381-387], which implies that parasin I was cleaved off from the N-terminal of catfish histone H2A. Parasin I showed strong antimicrobial activity, about 12-100 times more potent than magainin 2, against a wide spectrum of microorganisms, without any hemolytic activity. Circular dichroism spectra of parasin I indicated a structural content of 11% alpha-helix, 33% beta-sheet, and 56% random coils. The beta-sheet axial projection diagram of parasin I showed an amphipathic structure. Our results indicate that the catfish may produce parasin I from its histone H2A by a specific protease upon injury to protect against invasion by microorganisms.

High-level expression of human lactoferrin in milk of transgenic mice using genomic lactoferrin sequence.

In our previous study, transgenic mice were generated that expressed human lactoferrin (hLF) in milk using cDNA under control of the 2 kb bovine beta-casein promoter. The expression level of the protein in milk of 7 mice ranged from 1 to 200 microg/ml; 1 to 34 microg/ml in 6 mice and 200 microg/ml in 1 mouse. With the aim of inducing higher expression of the protein, we constructed an expression cassette comprised of 10 kb of the bovine beta-casein gene promoter and the hLF genomic sequence in place of the cDNA. The hLF genomic sequence of about 27 kb, spanning 23 kb of the entire coding region and 4 kb of the 3'-flanking sequence, was placed downstream the bovine beta-casein promoter. In total, 8 transgenic mice were generated from 31 mice (transgenic rate of 25.8%) born from the embryos microinjected with the 40-kb hLF expression cassette. Mammary-specific expression of the transgene was addressed by performing Northern hybridization of the total RNAs from various tissues of transgenic mice. Immunoblot analysis showed that the recombinant protein expressed in milk has the same molecular weight as the native protein. The amount of the protein in milk of 5 mice ranged from 60 to 6,600 microg/ml when judged by ELISA analysis. Three mice expressed the protein at the level higher than 500 microg/ml. These data suggest that the genomic lactoferrin sequence represents a valuable element for the efficient expression of the protein in milk of transgenic animals.

Combined characterization of composite tabular silver halide microcrystals by cryo-EFTEM/EELS and cryo-STEM/EDX techniques.

The combination of cryo-energy filtering transmission electron microscopy (EFTEM)/electron spectroscopic diffraction (ESD)/electron energy-loss spectroscopy (EELS) and cryo-energy-dispersive X-ray (EDX) analysis in the scanning transmission (STEM) and scanning (SEM) modes was applied for the characterization of composite tabular Ag(Br,I) microcrystals. A low-loss fine structure in EEL spectra between 4 and 26 eV was attributed to excitons and plasmons possibly superimposed with interband transitions and many-electron effects. The contrast tuning under the energy-filtering in the low-loss region was used to image the crystal morphology, defect structure (random dislocations and ¿111¿ stacking faults) and bend and edge contours as well as electron excitations in the microcrystals. Sharp extra reflections at commensurate positions in between the main Bragg reflections and diffuse honeycomb contours in ESD patterns of the microcrystals taken near the [111] zone were assigned to the number of defects in the shell region parallel to the grain edges and polyhedral clusters of interstitial silver cations, respectively. The imaginary part of the energy-loss function, Im (-1/epsilon), and the real and imaginary parts, epsilon1 and epsilon2, of the dielectric permittivity were determined by means of a Kramers-Kronig analysis. An assignment of exciton peaks based on calculations of electronic band structure of silver bromide is proposed. Inner-shell excitation bands of silver halide were detected in line with EDX-analyses. The energy-loss near-edge structure (ELNES) of the AgM4,5-edge governed by spin-orbital splitting between the 3d3/2- and 3d5/2-states has been evaluated. Combined silver and halide distributions were obtained by a three-window method (EFTEM) and by EDX/STEM including area mapping and line profiling of iodide.

Effect of the replication mode of a plasmid on the stability of multimeric endoxylanase genes in Bacillus subtilis.

Effect of the replication mode of a plasmid on the stability of tandemly multimerized endoxylanase genes and a gene dose-dependent expression of the endoxylanase were studied in Bacillus subtilis. The structural genes encoding an endoxylanase, carrying its original promoter and ribosomal binding sequence, were tandemly multimerized and cloned into the Escherichia coli-B. subtilis shuttle plasmid, pJH27 delta 88 or pMTL500e, which has a rolling circle-replicon or a theta (theta)-replicon in B. subtilis, respectively. The cloned dimers in pJH27 delta 88, which has a rolling circle-replicon, spontaneously rearranged to monomers in B. subtilis DB104, whereas those in pMTL500e, having a theta (theta)-replicon, were stably maintained. Expression level of the endoxylanase was proportional to the gene dosage in multimers. The endoxylanase activity in the supernatant increased from 80 U ml-1 with pMTL-1x containing a monomer of the gene to 165 U ml-1 with pMTL-4x containing a tetramer. These results indicate that high level expression of the endoxylanase gene can be obtained by tandemly multimerizing the genes in a plasmid with a theta (theta)-replicon.

Levels of intracellular protein and messenger RNA of mucin and lysozyme in normal human nasal and polyp epithelium.

OBJECTIVES: Mucus hypersecretion is a characteristic feature in chronic sinusitis with nasal polyps. The objective of this study is to examine whether the polyp epithelium itself contributes to a certain extent to the increased mucous secretions in chronic sinusitis with nasal polyps, and if it does, to determine which mucin genes are responsible for the increased mucin secretion. METHODS: Three pooled samples of normal nasal epithelial cells from each subject were obtained by scrapings from the inferior turbinates of 30 healthy adult volunteers and nasal polyps from 6 patients who underwent intranasal ethmoidectomy and polypectomy. Isolated epithelial cells were used for total RNA isolation for reverse transcriptase polymerase chain reaction and cell lysates for immunoblotting. RESULTS: The intracellular level of mucin from polyp epithelium was 2.9 times higher than that of normal nasal epithelium (P < .05). Interestingly, MUC2 and MUC8 messenger RNA (mRNA) levels were clearly upregulated in polyp epithelium compared with those of normal turbinate epithelium. CONCLUSIONS: Polyp epithelium can be considered to contribute in part to increased secretion in chronic sinusitis with polyps, and increased mucous secretion might be related to the increased mRNA level of MUC2 or MUC8 or both.

Surgical anatomy of the nasofrontal duct: anatomical and computed tomographic analysis.

OBJECTIVES: Although complete anatomical knowledge of the nasofrontal duct has been of great importance, little is known about it. The aim of this study is to examine the drainage site of the nasofrontal duct and to investigate the anatomical boundaries of the nasofrontal duct according to the drainage site. STUDY DESIGN: One hundred sagittally divided adult head specimens were analyzed by computed tomography and dissection under the surgical microscope. METHODS: Computed tomography scans of 50 adult cadaver heads were taken sagittally at 1-mm intervals and coronally at 3-mm intervals to find the nasofrontal duct. One hundred specimens, made up of sagittally divided adult cadaver heads, were dissected under the microscope to study the structure of the nasofrontal duct. RESULTS: We identified the anterior, posterior, medial, and lateral boundaries of the nasofrontal duct. In the most common type, the superior portion of the uncinate process formed the anterior border and the superior portion of the bulla ethmoidalis formed the posterior border of the nasofrontal duct. The conchal plate formed the medial border and the suprainfundibular plate formed the lateral border of the nasofrontal duct. Other variations are described in detail. CONCLUSIONS: To widen the nasofrontal communication, removing the upper portion of the ground lamella of the ethmoid bulla, which is the posterior boundary of the nasofrontal duct, with cutting forceps seems to be a safe and easy method.

Molecular cloning and characterization of an endoxylanase gene of Bacillus sp. in Escherichia coli.

A gene encoding an endoxylanase of Bacillus sp. was cloned and expressed in Escherichia coli. The entire nucleotide sequence of a 1,620 bp SmaI fragment containing the endoxylanase gene was determined. The endoxylanase gene was 639 bp long and encoded 213 amino acids which showed up to 96% amino acid homology with other endoxylanases. The endoxylanase produced by E. coli harboring pKJX4 was purified by ion-exchange chromatography (DE-52 and CM-52) and its N-terminal sequence was determined to be Ala-Gly-Thr-Asp-Tyr-Trp-Gln-Asn-Trp-Thr-Asp-Gly-Gly-Gly-Thr. The endoxylanase expressed in E. coli was identical to that of the original Bacillus sp. whose molecular weight was approximately 20,400. Most of the produced endoxylanase was localized in the periplasmic space of E. coli. When the endoxylanase was reacted with 2% oat spelts xylan (w/v) at 40 degrees C for 10 h, the major product was xylobiose which is known to be a selective growth stimulant to one of the healthy intestinal microflora, Bifidobacteria.

Variability of the surgical anatomy of the neurovascular complex of the cerebellopontine angle.

The variability of the anatomic relationship of the anterior inferior cerebellar artery (AICA) to the facial (seventh) and vestibulocochlear (eighth) nerves was studied in 52 cerebellopontine angles (CPAs) from 26 adult cadavers. The AICA originated from the basilar artery (98.1%) or from the vertebral artery (1.9%) as a single (92.3% of CPAs) or duplicate (7.7%) artery. Each of the 52 CPAs had one or more arterial trunks that coursed in close proximity to the seventh and eighth cranial nerves and thus were said to be nerve-related. The nerve-related arterial trunks were divided into three segments based on their relationship to the nerves and meatus: the premeatal, meatal, and postmeatal segments. The nerve-related branches of the AICA gave rise to the internal auditory artery in 92.3% of the CPAs, the recurrent perforating artery in 78.8%, and the subarcuate artery in 30.8%. The importance of understanding the surgical anatomy of the neurovascular complex of the CPA when performing a vestibular neurectomy is reviewed.