A new minimal-invasive approach for total hip replacement in sheep

BACKGROUND

Over the last 50 years arthroplasty became the gold-standard treatment for disabling conditions of the coxofemoral joint. Variations of anterior, lateral, and dorsal incision have been applied, but as each approach requires the incision and reflection of various muscles to gain adequate exposure of the joint results are still controversial.

OBJECTIVE

The purpose of this study was to develop a minimal-invasive, tissue-sparing approach in sheep with reduced risks in animal testing.

METHODS

12 mature sheep underwent hip surgery as part of a study to evaluate a hip resurfacing system. In line with the preliminary cadaveric tests a modified, minimal-invasive, musclepreserving surgical approach was sought after.

RESULTS

We developed a surgical approach to the coxofemoral joint in sheep using only blunt tissue dissection after skin incision without any limitations in joint exposure or increased blood loss/duration of surgery.

CONCLUSION

Even though limitations occur and femoral orientation in sheep differs from man, joint forces have similar relative directions to the bone with similar bony and vascular anatomy. Therefore, this minimal-invasive muscle preserving approach might be a safe and comparable alternative in still inevitable animal testing.

Blunt dissection technique with finger and vessel skeletonization in the posterior vesical wall for abnormally invasive placenta previa

Purpose: This study described a new technique to minimize the bleeding resulted from aberrant engorged vessels and unintended bladder injury in cases with abnormally invaded placenta adjacent to posterior bladder wall at cesarean hysterectomy.Methods: After filling the bladder with 300 ml saline aberrant engorged vessels were identified and skeletonized between lower uterine segment and bladder with blunt dissection by index finger down to the distal end point of cervix.Results: This technique has beneficial effect on preventing bladder injury and reduces bleeding resulting from the aberrant vessels and the communicating vessels that were based around the vesicouterine fold and the cervico-vesical interface (in the lower part of the cervix); respectively.Conclusion: Our procedure may have some benefits including shorter operation time, lower amount of hemorrhage, and less bladder injury where anatomical landmarks are unclear, especially in abnormally invasive placentation adjacent to posterior bladder wall at cesarean hysterectomy.

Structural and functional integration between dorsal and ventral language streams as revealed by blunt dissection and direct electrical stimulation

The most accepted framework of language processing includes a dorsal phonological and a ventral semantic pathway, connecting a wide network of distributed cortical hubs. However, the cortico-subcortical connectivity and the reciprocal anatomical relationships of this dual-stream system are not completely clarified. We performed an original blunt microdissection of 10 hemispheres with the exposition of locoregional short fibers and six long-range fascicles involved in language elaboration. Special attention was addressed to the analysis of termination sites and anatomical relationships between long- and short-range fascicles. We correlated these anatomical findings with a topographical analysis of 93 functional responses located at the terminal sites of the language bundles, collected by direct electrical stimulation in 108 right-handers. The locations of phonological and semantic paraphasias, verbal apraxia, speech arrest, pure anomia, and alexia were statistically analyzed, and the respective barycenters were computed in the MNI space. We found that terminations of main language bundles and functional responses have a wider distribution in respect to the classical definition of language territories. Our analysis showed that dorsal and ventral streams have a similar anatomical layer organization. These pathways are parallel and relatively segregated over their subcortical course while their terminal fibers are strictly overlapped at the cortical level. Finally, the anatomical features of the U-fibers suggested a role of locoregional integration between the phonological, semantic, and executive subnetworks of language, in particular within the inferoventral frontal lobe and the temporoparietal junction, which revealed to be the main criss-cross regions between the dorsal and ventral pathways. Hum Brain Mapp 37:3858-3872, 2016. © 2016 Wiley Periodicals, Inc.

Excision of sebaceous cyst by intraoral approach: A case report

RATIONALE

Surgical removal of a sebaceous cyst is usually accomplished through an external incision, which inevitably results in a scar. Herein, we described an intraoral approach for excising sebaceous cysts located in the lip or cheek near lip commissure, to avoid a skin scar.

PATIENT CONCERNS

Removal of the cyst but without leaving a scar on the face.

DIAGNOSES

Six patients were diagnosed with a subcutaneous cyst located in the lip or cheek near lip commissure.

INTERVENTIONS

We implemented an intraoral approach to excise the cyst, wherein an intraoral incision was made and blunt dissection was performed through the buccinator muscle or orbicularis oris muscle until the cyst wall was seen. The cyst was then dissected from the surrounding subcutaneous tissue by careful blunt dissection with a hemostat and completely removed through the intraoral incision.

OUTCOMES

All patients had complete recovery, with no recurrence or complaints for at least 6 months after the surgery.

LESSONS

A sebaceous cyst located in the lip or cheek near lip commissure can be excised by an intraoral approach through the mouth, which avoids a visible scar on the skin.

New insights in the homotopic and heterotopic connectivity of the frontal portion of the human corpus callosum revealed by microdissection and diffusion tractography

Extensive studies revealed that the human corpus callosum (CC) plays a crucial role in providing large-scale bi-hemispheric integration of sensory, motor and cognitive processing, especially within the frontal lobe. However, the literature lacks of conclusive data regarding the structural macroscopic connectivity of the frontal CC. In this study, a novel microdissection approach was adopted, to expose the frontal fibers of CC from the dorsum to the lateral cortex in eight hemispheres and in one entire brain. Post-mortem results were then combined with data from advanced constrained spherical deconvolution in 130 healthy subjects. We demonstrated as the frontal CC provides dense inter-hemispheric connections. In particular, we found three types of fronto-callosal fibers, having a dorso-ventral organization. First, the dorso-medial CC fibers subserve homotopic connections between the homologous medial cortices of the superior frontal gyrus. Second, the ventro-lateral CC fibers subserve homotopic connections between lateral frontal cortices, including both the middle frontal gyrus and the inferior frontal gyrus, as well as heterotopic connections between the medial and lateral frontal cortices. Third, the ventro-striatal CC fibers connect the medial and lateral frontal cortices with the contralateral putamen and caudate nucleus. We also highlighted an intricate crossing of CC fibers with the main association pathways terminating in the lateral regions of the frontal lobes. This combined approach of ex vivo microdissection and in vivo diffusion tractography allowed demonstrating a previously unappreciated three-dimensional architecture of the anterior frontal CC, thus clarifying the functional role of the CC in mediating the inter-hemispheric connectivity. Hum Brain Mapp 37:4718-4735, 2016. © 2016 Wiley Periodicals, Inc.