BACKGROUND: A side effect of spinal anesthesia is post-dural puncture backache (PDPB), which is characterized by ongoing discomfort at the location of the spinal puncture without any radicular pain. This study aims to compare the incidence and severity of post-dural puncture back pain following spinal anesthesia by median versus paramedian technique in obese female patients.
METHODS:  A prospective randomized comparative study on 120 female patients, aged 20-50 years with a BMI of 30-40 kg/m2 and American Society of Anesthesiologists physical status II, scheduled for elective surgery under spinal anesthesia, was included in the study. Patients were randomly divided into two groups, with 60 patients in each group. Group P uses the paramedian approach for spinal anesthesia, and group M uses the midline approach for spinal anesthesia.
RESULTS: Low back pain incidence was lower in group P than in group M at seven days, but at one month and after, its incidence remained the same in both groups. No difference in the severity of pain was observed.
CONCLUSIONS: The occurrence of back pain in the first seven days of surgery was significantly more frequent with the median approach. The pain severity decreased as the time passed from day seven to three months of follow-up. There is no difference in the severity of pain with either approach at different intervals.

BACKGROUND: Coccydynia is pain in the coccyx that typically occurs idiopathically or from trauma. Most forms are self-limiting. However, if symptoms persist, nonsurgical treatment options can include offloading, NSAIDs, physical therapy, and steroid injections. If all treatment options fail, a growing body of evidence supports a coccygectomy for symptomatic relief. The standard approach for a coccygectomy involves a midline incision cephalad to the anus along the gluteal cleft. Historically, this method has had high rates of infection.
OBJECTIVE: To improve healing and decrease infection rate, we propose the paramedian approach to a coccygectomy. This approach has the benefit of distancing the surgical site from the anus, diminishing the crevice effect of the incision, and increasing the dermal and subdermal thickness for improved surgical closure.
METHODS: We present a case series study of 41 patients who underwent the paramedian approach coccygectomy using a 4 to 6 cm incision, approximately 0.5 to 1.5 cm lateral to the midline, for coccyx removal. These patients were evaluated postoperatively to determine infection rate and various outcome measures.
METHODS: Forty-one patients suffering from refractory coccydynia had a coccygectomy via the paramedian approach between 2011 and 2022 by the senior author.
METHODS: Outcome measures included self-reported measures (Oswestry Disability Index (ODI), Visual Analogue Scale (VAS) pain scale and satisfaction with procedure), physiologic measures (presence of infection and treatment provided) and functional measures (return to vocation/avocation).
METHODS: Data was compiled and transferred to Microsoft Excel and analyzed. Two-tailed T-tests were used to compare the patient improvement in VAS and ODI as appropriate for statistical analysis.
RESULTS: The patients\' average age was 45.8 years. Patients\' average body mass index was 27.9, with 71% of patients overweight or obese. A total of 68% of patients were female. Trauma was the most common precipitating factor (75.6%). Five patients presented with postoperative complications (12.1%), one requiring an incision and drainage, and four others were treated with antibiotics for wound erythema. Postoperative evaluations showed continual improvement, with the most significant improvement reported greater than 1-year postoperatively. The Visual Analogue Scale for pain dropped from 7.5 to 2.3 (p<.001), and the Oswestry Disability Index improved from 30.1 to 9.6 (p<.001). A total of 86.7% of patients reported either a good or excellent result.
CONCLUSIONS: Coccygectomies via the midline approach have a variable infection rate, likely due to proximity of the incision to the anus and due to the crevice effect of the gluteal cleft in terms of aeration. These contributing factors are overcome in the paramedian approach, making it an effective option for treating refractory coccydynia that is nonresponsive to conservative management.

BACKGROUND: Pre-procedural ultrasound can be used to identify the subarachnoid space in difficult spinal procedures. However, multiple punctures can result in numerous complications, including post-dural puncture headache, neural trauma, and spinal and epidural haematoma. Thus, the following hypothesis was proposed: in contrast to the conventional blind paramedian dural puncture, pre-procedural ultrasound results in a successful dural puncture on the first attempt.
METHODS: In this prospective, randomised controlled study, 150 consenting patients were randomly assigned to one of the two groups: ultrasound-guided paramedian (UG) and conventional blind paramedian (PG). In the UG paramedian group, pre-procedural ultrasound was performed to mark the insertion site, whereas, in the PG group, the landmark technique was used. A total of 22 different anaesthesiology residents performed all subarachnoid blocks.
RESULTS: The time taken to perform spinal anaesthesia in the UG group was 38-49.5 s, which is shorter than the time taken in the PG group, which was 38-55 s, with a p-value < 0.046, which is statistically significant. The primary outcome of a successful dural puncture on the first attempt was not significantly higher in the UG group (49.33%) than in the PG group (34.67%), with a p-value < 0.068. The number of attempts taken for a successful spinal tap in the UG group was a median of 2.0 (1 to 2), and the PG group had a median of 2 (1 to 2.5), with a p-value < 0.096, which is statistically non-significant.
CONCLUSIONS: Ultrasound guidance showed improvement in the success rate of paramedian anaesthesia. In addition, it improves the success rate of dural puncture and the rate of puncture on the first attempt. It also shortens the time required for a dural puncture. In the general population, the pre-procedural UG paramedian group did not outperform the PG paramedian group.

Epidermoid cysts of the pineal region are a rare entity. Herein, the authors describe the endoscopic resection of a recurrent pineal region epidermoid by way of a supracerebellar infratentorial approach. The patient was positioned in the semiseated upright position with head tilted to the right and slightly flexed, maximizing gravity-based cerebellar retraction, and a paramedian craniotomy was performed owing to the gradual flattening of the tentorium from medial to lateral. This setup, in tandem with the enlarged viewing window achieved by use of 0°, 30°, and 70° endoscopes, afforded the necessary access to achieve a satisfactory resection through this anatomical corridor. The video can be found here: https://stream.cadmore.media/r10.3171/2021.4.FOCVID2131.

BACKGROUND: The development of back pain following epidural analgesia is one reason for patient refusal of neuraxial analgesia. The primary endpoint of this study was to compare the incidence and severity of back pain following midline and paramedian epidural technique. The secondary endpoint was to identify the risk factors associated with the occurrence of back pain.
METHODS: This prospective randomized study included 114 patients receiving thoracic epidural catheterization for pain management following upper abdominal or thoracic surgery. Patients were allocated to either the midline or the paramedian group by computer-generated randomization. An investigator who was blinded to the patient group interviewed patients at 24, and 48 h, and 3-5 days after surgery about the existence of back pain and its severity.
RESULTS: The total incidence of back pain following epidural anesthesia was 23.8% in the midline group and 7.8% in the paramedian group. The numerical rating scale of back pain was not different between the two groups at 24 h and 4 days after surgery. The paramdian technique was associated with a lower incidence of back pain than the midline technique (95% confidence interval 0.05-0.74, odds ratio 0.2, P < 0.01). However, the number of attempts, surgical position, body mass index, and duration of surgery were not associated with back pain.
CONCLUSIONS: This study showed that the midline group of thoracic epidural analgesia demonstrated higher incidence of back pain than the paramedian group. However, the pain was mild in intensity and decreased with time in both groups.

Midline and paramedian mandibulotomies both have distinct anatomical and surgical strengths. A retrospective study was performed at Chang Gung Memorial Hospital, Linkou Branch between 2014 and 2019 to investigate how the osteotomy site (midline (n = 221) or paramedian (n = 44)) and type (straight, notched, or stair-stepped) affect postoperative and post-radiotherapy complications in patients undergoing wide excision of tongue cancer with flap reconstruction. Midline mandibulotomies were predominantly of the straight osteotomy type, while paramedian mandibulotomies were mostly notched type (P < 0.001). Comparably low elective tooth extraction rates were found in both approaches (P = 0.556). Paramedian mandibulotomy showed a higher osteoradionecrosis rate (P = 0.026), but there was no significance in the sub-analysis of individual types. Paramedian sites were associated with more early infection (P = 0.036) and plate exposure (P = 0.036) than midline sites with the straight osteotomy type, but complication rates did not differ significantly for the notched and stair-stepped types. Paramedian sites (P = 0.020) and notched types (P = 0.006) were associated with higher odds of osteoradionecrosis in the univariable logistic regression analysis, but only the notched type remained significant in the multivariable analysis (P = 0.048). In conclusion, paramedian sites increased the rate of osteoradionecrosis, and correlation with the osteotomy type resulted in more osteoradionecrosis in notched types and more complications in straight paramedian mandibulotomies.

The Artery of Percheron (AOP) is an uncommon anatomic variant that provides arterial supply to the paramedian region of the thalami and bilaterally to the rostral part of the midbrain; it is a solitary arterial trunk that branches from a proximal segment of the posterior cerebral artery (PCA). Although AOP infarction results in a characteristic pattern of ischemia-namely bilateral paramedian thalamic infarct with or without midbrain involvement-it may cause diagnostic difficulties due to the variety of its clinical presentations and wide differentials, as well as its small diameter and the difficulty of obtaining visualization through diagnostic imaging. Early neuroimaging of AOP infarction and correct diagnosis are mandatory for early initiation of the appropriate treatment and better patient outcomes. In this study, we discuss imaging the patterns of AOP infarction and its differentials and clinical presentation.

OBJECTIVE: This study aimed to compare the influences of postoperative oral function in patients with median or paramedian mandibulotomy during the radical resection of tongue carcinoma and to provide evidence for the choice of osteotomy location for mandibulotomy.
METHODS: The clinical data of 126 patients who underwent combined radical neck dissection with mandibulectomy and glossectomy followed by simultaneous reconstruction were analyzed retrospectively. The patients were divided into two groups according to the position of mandibulotomy: median mandibulotomy group (median group, n=60) and paramedian mandibulotomy group (paramedian group, n=66). The fourth edition of the University of Washington Quality of Life Questionnaire (UW-QOL) was used to compare the differences in oral functions, such as swallowing, mastication, and speech, between the two groups during regular follow-up. SPSS 24.0 software package was used for statistical analysis, and P<0.05 was considered statistically significant.
RESULTS: Six months after the operation, no significant differences in swallowing, mastication, and speech functions were found between the median and paramedian groups. However, the swallowing and speech functions in the paramedian group were better than those in the median group 1 year after the operation (P<0.05), whereas no statistical difference in mastication function was observed between the two groups.
CONCLUSIONS: Evaluation of the postoperative oral function results showed that paramedian mandibulotomy was a better surgical approach than median mandibulotomy. Paramedian mandibulotomy is worth prioritizing in the radical resection of tongue carcinoma.
目的 比较正中或旁正中下颌骨截骨术对舌癌患者口腔功能的影响，为下颌骨截骨位置的选择提供依据。方法 回顾性分析经下颌骨截骨入路进行舌颌颈联合根治及缺损修复重建的126例舌癌患者的临床资料。根据截开下颌骨位置的不同，分为下颌骨正中截骨术组（正中组，n=60）和下颌骨旁正中截骨术组（旁正中组，n=66）。术后定期随访，应用华盛顿大学生存质量问卷（UW-QOL）第四版比较2组患者术后吞咽、咀嚼和语音等口腔功能的差异。采用SPSS 24.0软件包进行统计学处理，P<0.05为差异有统计学意义。结果 术后6月，正中组与旁正中组吞咽、咀嚼及语音功能评分差异均无统计学意义；术后1年，旁正中组患者吞咽和语音功能评分优于正中组（P<0.05），但咀嚼功能评分差异无统计学意义。结论 经旁正中下颌骨截骨入路进行舌颌颈联合根治，术后患者口腔功能优于经正中下颌骨截骨入路。.

The high versatility and efficacy of the contralateral interhemispheric approach is demonstrated in this resection of an arteriovenous malformation (AVM). This patient had a large AVM along the medial frontal lobe amenable to approach via the contralateral interhemispheric approach. The head was rotated to permit gravity retraction of the ipsilateral hemisphere to the AVM, avoiding the use of rigid retractors. Under the guidance of neuronavigation, the falx was opened to permit visualization of the AVM. Circumdissection with a disconnection of the nidus was performed in a standard fashion. Postoperative angiography confirmed complete removal of the AVM. The patient gave informed consent for surgery and video recording. Institutional review board approval was deemed unnecessary. Used with permission from Barrow Neurological Institute, Phoenix, Arizona.

UNASSIGNED: Although the most popular anesthesia technique for cesarean is spinal anesthesia, its most common complication is post-dural puncture headache (PDPH).
UNASSIGNED: We aimed to determine the effect of median and paramedian approaches during spinal anesthesia on PDPH in patients undergoing cesarean section.
UNASSIGNED: 200 pregnant women between the ages of 19-45 years, ASA physical status II, scheduled to undergo elective cesarean section under spinal anesthesia, were studied. The patients were randomized into two groups: Group M; (n = 100) spinal anesthesia with the median approach, Group PM; (n = 100) spinal anesthesia with paramedian approach. The patients were questioned for the possible occurrence of PDPH on the first, third and seventh postoperative days. A telephone follow-up call was used if the hospital stay was shorter than seven days. Post-dural puncture headache was evaluated according to the International Classification of Headache Disorders (ICHD-III) diagnostic criteria. Normally distributed data were summarized using mean and standard deviation. Skewed data were summarized using median (range).
UNASSIGNED: A total of 200 patients completed the study. There were no statistically different between the groups by comparing the incidence and characteristics of PDPH (32% vs. 28%, P = 0.548). Most patients rated their pain intensity during PDPH as mild to moderate in both groups (p = 0.721). PDPH onset time was 2 (1-4) days in Group PM versus 3 (1-7) days in Group M (p = 0.173). No patient needed for epidural blood patch in both groups.
UNASSIGNED: Spinal anesthesia with a median or paramedian approach at cesarean section has no effect on the incidence of PDPH, but we believe that there has been a need for further studies with larger or different patient populations.