Selected References. Fernandez-Miranda, J. High-definition fiber tractography of the human brain: neuroanatomical validation and neurosurgical applications. Neurosurgery , 71 2 , Abhinav, K.

High-definition fiber tractography for the evaluation of perilesional white matter tracts in high-grade glioma surgery. Neuro-oncology , 17 9 , High-definition fiber tracking guidance for intraparenchymal endoscopic port surgery.

Journal of neurosurgery , 5 , Meola, A. Human connectome-based tractographic atlas of the brainstem connections and surgical approaches. Neurosurgery , 79 3 , Stanford Fiber Tractography Lab - Surgical Planning. Selected References 1. Inside the Fiber Tractography Lab Home Anatomical Study Surgical Planning Stroke Research More On White Matter Tracts Team.

a In this patient, the HoloLens marking is displaced partly due to discrepancies in patient arm position between the MRI and the surgical position. b In this patient, the palpating surgeon initially marked a lesion in a different region of the breast, which may have been benign.

This example shows how important it is for surgeons to have access to additional technologies to identify malignant tumors. Suba Srinivasan is an alumnus of the BMR group. Brian Hargreaves PhD.

Professor of Radiology , and by courtesy Electrical Engineering and Bioengineering. Radiological Sciences Lab RSL Clinical Body MRI Section Radiology Department. Directions: Lucas Ctr. or Porter Dr. BMR Group. A Mixed-Reality System for Breast Surgical Planning.

Brian A. Professor of Radiology Radiological Sciences Laboratory and, by courtesy, of Electrical Engineering and of Bioengineering.

Radiological Sciences Lab RSL Clinical Body MRI Section Radiology Department. Directions: Lucas Ctr. or Porter Dr. BMR Group. A Mixed-Reality System for Breast Surgical Planning. Brian A. Professor of Radiology Radiological Sciences Laboratory and, by courtesy, of Electrical Engineering and of Bioengineering.

Bruce Daniel. The sequence random generation was maintained in sequentially numbered, opaque, and sealed envelopes. One researcher informed the participant by phone to which group they were allocated before the schedule of the MRI exam.

The analysis of continuous variables was performed using measures of central tendency including mean and median and measures of dispersion. The Kolmogorov—Smirnov and Shapiro—Wilk tests were applied to assess data distribution characteristics. We used the Chi-square test or Fisher's exact test to compare outcomes with categorical variables.

If it was non-normally distributed data, we used the nonparametric Mann—Whitney U test. The risk ratio was used to estimate the effect size for dichotomous outcomes effect size for dichotomous outcomes.

The time-to-local recurrence and OS were analyzed using the Kaplan-Meyer survival function with a stratified log-rank test and HRs estimated via a stratified Cox regression model to compare treatment groups. The follow-up losses and deaths were censored. The data were analyzed using the SPSS v The analyses were performed in the intention to treat the population, which included all randomized patients.

Overall, patients were eligible for the trial; from those, provided written consent and were included in the BREAST-MRI trial: in the MRI group and in the control group. Further, two participants refused to perform breast MRI and were withdrawn.

The CONSORT flowchart of included participants is presented in Fig. The baseline characteristics were similar between groups Table 1 , except for adjuvant chemotherapy. An exploratory analysis considering only invasive carcinoma showed no difference in mean tumor size, being 2.

The mean time from randomization to surgery was different between groups, Preoperative localization was performed in all conservative breast surgeries when necessary: the tumor was palpable in cases The MRI group had 46 additional biopsies in 44 patients versus 22 additional biopsies in 21 patients in the control group p 0.

Of 46 additional biopsies in the MRI group, 25 were motivated by MRI, 13 by mammography, and 8 by USG versus 14 by mammography and 8 by USG in the control group. Eleven out of 65 After a median follow-up time of six years, there were two 1.

The 5. Local recurrence-free survival and Overall survival. a Local recurrence-free survival. b Overall survival. After a median follow-up time of 5.

The OS was Overall, 21 8. Of 21 patients whose surgical management was changed in the MRI group, nine were submitted to additional biopsies guided by second-look ultrasound with the following results: five invasive carcinomas, one ductal carcinoma in situ, and three discordant benign. In the control group, only one 0.

Table 4. In an exploratory analysis to assess the potential role of MRI in dense breasts, we compared patients with dense breasts that had their surgery changed to mastectomy versus patients without dense breasts that had their surgery changed to mastectomy.

Re-excisions were necessary for 17 6. The final mastectomies rates were 26 Our results show that preoperative breast MRI did not change the local recurrence and overall survival rates in breast-conserving surgery candidates.

Additionally, preoperative breast MRI increased the mastectomy rates and did not reduce reoperation rates. Only a few studies have examined the long-term outcome effects of preoperative MRI.

A previous systematic review that included patients with published studies until demonstrated that 8-year disease-free survival did not differ between the MRI A larger retrospective study involving patients with invasive cancer found that local recurrence rates after 8 years with and without MRI were 4.

Despite local recurrence-free survival early data with 6-year follow-up in our trial, it corroborates with those data. In this cohort, there was an increase in the percentage of adjuvant chemotherapy in the MRI group, explained by the largest median tumor in this group, although this fact did not have an impact on the local recurrence rate RR 0.

Based on the observed rate of LR in our study being significantly lower than predicted, the study lacked the power to identify a significant difference in rates of LR or survival.

The criteria for modifying the surgical management based on additional findings in MRI are different in prospective and retrospective studies published until now. Our study confirmed these findings with an increase of 8. The MRI as a preoperative evaluation in breast cancer patients increases the risk of mastectomy by 3.

The core issue about the MRI exam to pre-operatory staging is the unnecessary mastectomies, due to false positive findings.

Three out of five clinical trials performed the correlation between breast MRI and histopathological findings [ 16 , 17 , 18 ], and two described the false positive rates.

Therefore, is not possible to identify the number of participants who have undergone mastectomy without investigating the additional foci which could affect the number of overtreatments. In our trial, the false positive rate was In this trial, no difference in reducing reoperation rates between the MRI and control groups was observed, which remains controversial in the literature.

Although retrospective studies showed robust evidence in reducing repeated surgeries [ 16 ], randomized studies have conflicting results on this subject [ 15 , 16 , 18 , 19 , 20 ]. Retrospective studies have a higher risk of bias, increasing the effect size, and leading to a spurious association [ 21 ].

Of the five randomized trials published on this subject, three did not show differences in reoperation with preoperative MRI [ 16 , 18 , 22 ], one found an increased number of additional procedures [ 20 ], and one reported a reduced number of additional surgeries [ 19 ].

POMB trial, the only one with a reduction of re-operative rates, was a prospective trial that included young patients [ 19 ]. There are five randomized studies evaluating the impact of conservative surgery on surgical planning, all of them had objective final mastectomy rates and repeat surgery [ 16 , 18 , 19 , 20 ].

Most of them included invasive and DCIS [ 18 , 19 , 20 ], one only Stage I tumor [ 15 ], and one only DCIS [ 16 ]. The number of participants was wide in trials. The COMICE trial included participants, of which invasive carcinomas [ 18 ].

The MONET trial included participants with BIRADS 3—5 lesions; of which were benign lesions and 81 were invasive breast cancer and 82 DCIS [ 20 ]; the POMB trial included participants with invasive and in situ does not mention the number in each arm.

Moreover, this trial included 54 participants undergoing neoadjuvant chemotherapy [ 19 ]. Bruck et al. included participants with stage 1 tumors [ 15 ], and IRCIS included only participants with DCIS tumors [ 16 ]. The criteria for conversion to mastectomy was tumor-to-breast volume ratio in one study [ 15 ], MRI lesion more than 1 cm longer than triple assessment [ 19 ], and more than 3 cm or multifocality [ 16 ] and not mentioned in 2 studies [ 18 , 20 ].

Regarding sample size calculation, four out of five described it [ 16 , 18 , 19 , 20 ]. The design of our trial has two novel strengths. To the best of our knowledge, the BREAST-MRI trial is the first to use randomized stratification based on mammographic density to evaluate the performance of breast MRI in different subgroups.

Furthermore, the selection of a measurable threshold to change surgical indication contributes to the literature by adding an objective criterion to the subjective choice of individual surgeons. However, the median tumor size for DCIS and invasive carcinoma in breast MRI was 2.

So, we believe that there was a real impact when it comes to planning conservative surgeries. As potential strengths of our study, we collaborated with breast radiologists with more than five years of experience that interpreted all imaging exams, and we followed patients rigorously, so there were only four losses on follow-up.

This trial's main limitations were the unbalance between groups regarding the use of adjuvant chemotherapy, the lack of the allocation concealment procedure, and unblinding evaluators' outcomes and low rate of local recurrence.

Nevertheless, the clinical stages were similar between groups; the protocol for chemotherapy treatment in our institution is based on clinical features, including a tumor size of more than 2. Despite the lack of allocation concealment procedure, only two patients refused to perform MRI in the intervention arm, and this is very unlikely to impact the outcome.

The other outcomes all local recurrences were confirmed by biopsy, death, and reoperation rate are very objective and unlikely to increase the detection bias. Another issue is the time from randomization to surgery; there is a statistical difference between groups showing ten days more in the MRI group, which is explained by the need for additional biopsy.

In both groups, time took at least two months to undergo surgery. This prolonged time may happen due to our institution's characteristic, the biggest tertiary hospital in Brazil, with a massive number of patients with low-quality imaging studies before the referral; this incurs due to the necessity to repeat most of the exams after their first visit at ICESP.

Our group will publish updated results when we reach 20 years of follow-up to evaluate this outcome. As for implications in clinical practice, MRI is widely used in preoperative breast cancer patients leading to higher mastectomy rates with no strong evidence that it could avoid a local recurrence.

In daily practice, its use should be based on shared decisions with breast cancer patients. Regarding future research, in the era of treatment de-escalation and based on the scientific GAP about local recurrence protection, we believe that the publication of the interim analysis is of essential importance to guide other groups and can also be used as a basis for multicentric studies since this the first trial with local recurrence-free survival as a primary outcome.

We also believe that further analysis to assess the cost-effectiveness of breast MRI according to the number of unnecessary biopsies or surgeries must be planned. This randomized controlled trial supports that preoperative breast MRI may increase the mastectomy rates and does not routinely change local relapse-free survival, overall survival, and reoperation rates in early-stage breast cancer in this interim analysis, and its use should be based on shared decision-making with patients.

Fisher B, Anderson S, Bryant J, Margolese RG, Deutsch M, Fisher ER, Jeong J-H, Wolmark N Twenty-year follow-up of a randomized trial comparing total mastectomy, lumpectomy, and lumpectomy plus irradiation for the treatment of invasive breast cancer. N Engl J Med — Article PubMed Google Scholar.

Veronesi U, Cascinelli N, Mariani L, Greco M, Saccozzi R, Luini A, Aguilar M, Marubini E Twenty-year follow-up of a randomized study comparing breast-conserving surgery with radical mastectomy for early breast cancer.

Pilewskie M, Morrow M Margins in breast cancer: How much is enough? Cancer — Kurniawan ED, Wong MH, Windle I, Rose A, Mou A, Buchanan M, Collins JP, Miller JA, Gruen RL, Mann GB Predictors of surgical margin status in breast-conserving surgery within a breast screening program.

Ann Surg Oncol — Meier-Meitinger M, Rauh C, Adamietz B, Fasching PA, Schwab SA, Haeberle L, Hein A, Bayer CM, Bani MR, Lux MP, Hartmann A, Wachter DL, Uder M, Schulz-Wendtland R, Beckmann MW, Heusinger K Accuracy of radiological tumour size assessment and the risk for re-excision in a cohort of primary breast cancer patients.

After the surgery, tractography can be conducted again to demonstrate once-distorted tissues returning to normal following removal of the lesion. Sometimes the surgeon is left with no choice but to remove critical white matter structures due to invasion by highly-aggressive tumors.

In these cases, tractography may give an idea of the functional consequences that the patient may encounter following surgery. A future direction for tractographic neurosurgical planning involves the integration of HDFT with virtual reality VR techniques.

Stanford Neurosurgery has been a pioneer in establishing routine VR implementation for neurosurgical planning. VR permits the surgeon to visualize complex neuroanatomy including bone, blood vessels, nerves and brain as a fully-immersive, manipulatable 3-dimensional model.

Selected References. Fernandez-Miranda, J. High-definition fiber tractography of the human brain: neuroanatomical validation and neurosurgical applications. Neurosurgery , 71 2 ,

Neurosurgeons deal with a wide range of pathology including tumors, vascular malformations, endocrine disorders and epilepsy, amongst others. Prior to the introduction of magnetic resonance imaging MRI , there was no accurate way to visualize neural tissue in the brain at an adequate level of detail.

Tractography adds an extra layer to this visualization ability. It permits white matter architecture to be studied and is particularly useful to show how tumors and other space-occupying lesions distort surrounding tissues.

When conducted pre-operatively, tractography permits the surgeon to visualize a lesion and the structures surrounding it. Every region of the human brain serves a function and utmost care must be taken by the neurosurgeon to prevent unnecessary damage to healthy tissues adjacent to the pathology.

Damage to surrounding structures may produce undesirable post-operative outcomes. Tractography permits the surgeon to visualize the critical functional tissues surrounding the lesion and modify their angles of approach in order to minimize damage and ensure function is maintained post-operatively.

After the surgery, tractography can be conducted again to demonstrate once-distorted tissues returning to normal following removal of the lesion. Sometimes the surgeon is left with no choice but to remove critical white matter structures due to invasion by highly-aggressive tumors. In these cases, tractography may give an idea of the functional consequences that the patient may encounter following surgery.

A future direction for tractographic neurosurgical planning involves the integration of HDFT with virtual reality VR techniques. Stanford Neurosurgery has been a pioneer in establishing routine VR implementation for neurosurgical planning. VR permits the surgeon to visualize complex neuroanatomy including bone, blood vessels, nerves and brain as a fully-immersive, manipulatable 3-dimensional model.

Selected References. Other imaging techniques have also been used in image guided therapy or intra-operative image-to-patient registration. Optical molecular imaging like fluorescence molecular imaging FMI has been used as a meticulous surgical guiding during the tumor resection 33 - Unlike the IGT listed above, this FMI technique is using fluorescent dye to label the tumor tissue under an image-guided navigation system Surgeons, traditionally determine the mass margin for biopsy or resection only by experience on pathological anatomy, nowadays can distinguish the malignant tissue by the previous fluorescent marker and perform a precise operation.

Some preclinical results using the near infrared imaging NIR technique unite with other imaging methods like ultrasonography 38 , MRI 39 and X-ray CT 40 compensate for the depth issues and have already demonstrated the possibility of using the FMI guided multi-modality method to precisely excise tumors.

Still, the intra-operative guided system supplying 3D precise detection of tumor margin is not yet commercial available and requires future development efforts. Patient-to-image intraoperative registration is an important bridge which connects imaging navigation with patient.

This is a critical step to give surgeons precise guidance information. The traditional methods for patient-to-image registration use marker based point-surface matching registration method 41 - The limitation of this method is that it can only be used to registration a limited area near the point cloud center One recent study by Fan et al.

This lightweight, portable 3D scanner based intra-operative registration technique greatly facilitates the preoperative registration procedure. To unify this registration technique into modern IGT platform will be a promising future.

Recently the technology of 3D-printing is spreading fast not only in the industry and business area, but also in clinical application. Due to this technology can turn a digital 3D model into a 3D replicated object; it has the capabilities to largely improve the precision of modern surgical plan by combining with other preoperative plan and intraoperative navigation techniques.

The basic workflow of 3D printing is showed in Figure 1 , indicating that this advanced technology has broad applications not only in clinical field, but also in biomedical engineering field. For the resection of tumor with an intricate anatomical pathology such as like pelvic bone tumor, it is indispensable to perform a preoperative pathological anatomy analysis and rehearsal before the real operation The patient 3D-printed replica can provide surgeons opportunities to optimize the approach during pre-operation meetings Silberstein et al.

This 3D printed model solves the disadvantage of 3D imaging which is limited in depth appreciation displayed on 2D screen. As the 3D printing technology can produce a patient specific anatomical model, it also can be used to design a personalized surgical implant jig or prosthesis by using computer aided design CAD or Solidworks.

Qiao et al. The results of reduction were obtained from three tibial fractures with an average lateral displacement of 2. Kusaka et al. As reviewed in the previous sections of this article, the advancement of surgical planning and navigation techniques comes with higher requirements on technical support, equipment and computational power.

Cutting edge surgical techniques are therefore restricted to institutions with sophisticate equipment and specific technical supports. Previous studies of graphics processing unit GPU -based medical image computing techniques had emphasized that with the rapid development of GPU, the parallel GPU computation technique will greatly enhance the medical imaging processing performance However, this parallel acceleration computation may largely rely on the hardware performance of the computing machine.

Such limitations are solvable through employing cloud technologies. It is crucial to analyses the feasibility to migrate surgical planning and navigation techniques from traditional platforms to clouds with a cost-efficient and user-friendly yet secure fashion.

Comparing to other medical fields, cloud computing is relatively new in the field of surgical planning and navigation, only limited previous literatures are available related to the topic. The majority of them were pioneer studies without actual implementation discussing whether cloud-computing is advantageous in clinical uses 52 , Two of the recent studies related to cloud surgical planning have been reviewed which contain relevant reference value to any computational-power-dependent surgery techniques.

Maratt and colleagues performed a research against the accuracy, efficiency and compliance of cloud-based surgery planning in They showed that preoperative planning for total hip arthroplasty on cloud-based software produce comparable result in terms of accuracy with traditional acetate overlay templating with more than 2-fold efficiency.

They further stated that cloud-based digital templating provide additional benefits of cost saving, efficiency and workflow improvement for total hip arthroplasty In their specific case of total hip arthroplasty, digital surgical planning was a newly available, cloud-based system particularly for this purpose during the time.

Knowing that, Maratt et al. stressed in their study that for other medical applications or research, regulatory changes must be made before the advantages of cloud technologies can be realized.

Similar effort had been made by Schoenhagen, Zimmermann and Falkner who reported the application of cloud computing in clinical workflows of trans-catheter aortic valve replacement treatment in 8.

They are motivated to deploy such system due to trans-catheter aortic valve planning require intensive 3D modeling and produce large volume of image data which results in limited sharing ability. In attempts to resolve this counter-productive system, Schoenhagen et al.

adopt a cloud architecture where processing work and data storing are centralized to powerful cloud server. The resultant image data can be accessed by multiple less expensive computer clients.

Their model, however, was limited by network speed because of intense traffic between the clients and the central cloud server generated from image exchanges between clients and database 8. The above discussed cases demonstrated how cloud architecture can assist in preoperative planning through centralizing computational steps to cloud servers.

With increasingly computational-intense planning methodology being proposed and implemented, the importance of cloud computing will gradually emerge. It is believed that exploration in the direction of preoperative application of cloud computation can accelerate the process of surgical planning in individual hospitals.

With the help of the development of multimodality imaging, especially the fusion of functional imaging in pre-operative planning and modern image guided therapy in intra-operative navigating, surgeons are now able to operate a portion of extremely risky procedures with both high level of safety and accuracy.

However, the current use of multimodal MRI imagining for tumor surgical planning and navigation is largely restricted to a few institutions with strong technical support from physicists and imaging and image post processing specialists to maintain this entire preoperative planning system.

As the development of medical imaging technology advanced, the increasing number of imaging processing systems and intra-operative imaging guided platforms became powerful but also complicated. Surgeons tend to like a reliable, stable, and user-friendly platform.

Unfortunately, due to the fact that the commercial imaging platforms are closed source, standardization of surgical procedures can hardly be realized by surgeons. Given that surgical planning and navigation of tumor biopsy and resection are highly dependent on digital imaging and registration, adopting cloud architecture can improve clinical workflow.

Nevertheless, it is stressed that the aforesaid advantages are only the most obvious benefits of cloud computing, previous researchers focused mainly on hardware cost-efficiency improvements and yet to further explore other potential benefits brought by cloud technologies.

More importantly, cloud-computing can enable better collaboration among people because its usage is not restricted by the physical locations of the users and the server. Experienced individuals from all over the world can be invited to be involved in the planning and enable other surgeons to learn from their invaluable experience such as accurate identification of tumor mass region.

Under suitable circumstances, surgeons can also allow the patients to receive updates of their surgical planning without much additional effort and hence, allowing them to gain better understanding of the risks and be able to make relevant decisions regarding the surgery.

Nonetheless, it is also necessary to recognize the limitation of cloud computation before deciding whether it is suitable for the intended applications.