Welcome to this month's rundown of Dermatologic Surgery, the March twenty twenty-six issue. We've got four pieces to get through today — a review of outcome measurement tools after Mohs surgery, an original study on cooling technology for keloid injections, a how-we-do-it piece on an old-school technique for calvarial bone involvement, and a systematic review of intraoperative scar-optimization strategies. Let's get into it.

First up is a review article out of several UK dermatology departments, titled "Assessment of Clinician- and Patient-Reported Outcomes After Mohs Micrographic Surgery." The clinical problem here is one you already live with — Mohs surgery for head and neck keratinocyte cancers leaves scars that affect quality of life, cosmesis, and function, and generic dermatology quality-of-life tools like the Dermatology Life Quality Index or Skindex simply weren't built to capture that. The gap the authors are addressing is the absence of a clear map of which instruments are actually validated for this specific population — facial skin cancer patients undergoing Mohs.

Methodologically, this is a narrative review conducted to SANRA reporting standards, with PubMed and Cochrane searches through January twenty twenty-five, and instrument quality graded loosely against COSMIN criteria — that's the consensus framework for judging health measurement tools on reliability, validity, and responsiveness. A narrative rather than systematic design makes sense here because the goal isn't pooling outcomes data, it's characterizing and comparing instruments, which is inherently a descriptive, qualitative synthesis task.

Sixteen articles made the cut, organized around five patient-reported outcome measures and five clinician or observer scar-assessment tools. On the patient-reported side, the Dermatology Life Quality Index and Skindex both get flagged as insensitive — patients often score near zero on these despite real cosmetic or psychosocial distress, because neither tool asks about fear of recurrence or appearance-specific concerns. The Skin Cancer Index, developed specifically for cervicofacial keratinocyte cancer, comes out as the strongest performer, with excellent internal consistency and demonstrated responsiveness to treatment — meaning scores actually move in the direction you'd expect after reconstruction, and it correlates well with self-esteem and cancer-worry measures. The Skin Cancer Quality of Life Impact Tool, and its newer short-form version that dropped the recurrence and fear-of-dying items as less relevant to low-risk disease, offers a shorter, complementary option better suited to routine clinic use. And the FACE-Q Skin Cancer Module, validated in over three hundred Mohs patients with facial basal cell, squamous cell, and melanoma, rounds out the strongest tier — it's got five distinct scales covering appearance satisfaction, cancer worry, psychosocial distress, and patient experience, and Rasch analysis has trimmed it down to a very manageable item set.

On the clinician side, the Patient and Observer Scar Assessment Scale, or POSAS, is the standout because it merges objective observer scoring with patient-reported symptoms in one instrument — that dual perspective is exactly what the authors argue you need. Vancouver Scar Scale and Manchester Scar Scale offer more traditional observer-only structured assessments, while the Stony Brook Scar Evaluation Scale and simple global cosmesis visual analog scales are really only good for quick, early postoperative checks rather than long-term outcome tracking.

There's no results-versus-limitations arc here since this is a synthesis piece, but the practical takeaway is concrete: if you're doing any kind of outcomes tracking, quality improvement work, or trial design in your Mohs practice, the combination worth adopting is the Skin Cancer Index or FACE-Q Skin Cancer Module for the patient-reported side, paired with POSAS for the clinician-scored side. That combination is well validated for exactly this population and captures both what you see and what the patient feels — generic dermatology quality-of-life tools should be considered inadequate for this purpose going forward.

Second article, and this one's a genuine original study: "Efficacy of Precision Cryotherapy in Reducing Pain During Intralesional Injections for Keloids," out of Beth Israel Deaconess and Harvard. The background is straightforward — intralesional triamcinolone, sometimes with five-fluorouracil, is painful, with prior literature citing average pain scores in the five-to-eight-out-of-ten range, painful enough that it can drive treatment discontinuation. A noncontact carbon dioxide cryotherapy device, FDA-approved in twenty twenty-two, cools skin to a controlled target temperature within a couple of seconds using real-time infrared thermosensing, and it's already shown pain benefit in laser tattoo removal, acne injections, and platelet-rich plasma procedures. Nobody had tested it for keloid injections specifically, which is the gap this paper fills.

The design is a single-center, prospective, twenty-patient split-lesion study — each patient had two injection sites, either two separate keloids or one keloid divided in half, with one side getting standard intralesional injection alone and the other getting the same injection with the cooling device applied throughout. Treatment order was randomized. This within-patient, split-site design is a smart methodological choice, and it's one the authors clearly leaned on deliberately — using each patient as their own control eliminates the substantial person-to-person variability in pain perception and pain reporting that would otherwise muddy a parallel-group comparison, and it let them keep every other variable — steroid concentration, volume, five-fluorouracil use — identical between the two sites, isolating cryotherapy as the only difference.

The results were clear and clinically meaningful, not just statistically significant: pain scores were two-point-four out of ten with the device versus five-point-nine without, a fifty-nine percent relative reduction, and that difference was highly significant statistically. Ninety-four percent of patients said they'd choose to use the device again. Side effects were minimal and self-limited — one patient had mild itching for two days, another had transient redness for less than a day, no pigment change or blistering.

In discussion, the authors frame the mechanism as cryotherapy lowering nerve conduction velocity and raising the nociceptor activation threshold, and they benchmark this fifty-nine percent reduction against vibration anesthesia, which achieved a more modest forty-four percent reduction in prior work, and contact cryotip cooling, which achieved a slightly larger sixty-six percent reduction but without the temperature regulation this device offers, meaning higher risk of overcooling, frostbite, or dyspigmentation. The honest limitations here are the small sample size, single-center design, absence of a true blinded placebo comparator — so some placebo effect can't be excluded — and worth flagging explicitly, this study was funded by the device manufacturer, which the authors disclose.

Practical takeaway — this leans toward practice-changing for anyone doing high volume of keloid or hypertrophic scar injections, simply because the device is reusable, reasonably affordable per procedure, and the effect size is large enough to matter to patients who currently dread these visits. But given the small sample and industry funding, it's fair to call this promising rather than definitively proven, and larger independent replication would strengthen the case before it becomes a universal standard.

Third article is a "How We Do It" piece from the Cincinnati Skin Cancer Center: "Use of Mohs Paste, Zinc Chloride, for Calvarial Outer Table Removal in Advanced Cutaneous Malignancy." No background-methods-results scaffold here — this is pure technique, reviving Frederic Mohs's original fixed-tissue chemistry for a very specific modern problem: cutaneous carcinoma on the scalp that's clinically fixed to bone and extends onto the calvarial outer table, a scenario that otherwise often triggers a neurosurgery or ENT referral and a trip to the operating room.

The protocol starts with imaging — any tumor fixed to bone gets a CT scan first, and if there's radiographic invasion beyond the outer table or into the dura, that's an automatic neurosurgery referral, though Mohs can still be used first to clear peripheral margins. If there's no deep invasion, standard Mohs proceeds down to periosteum, the patient is positioned supine or prone — critical detail, because periosteal elevation carries a real risk of air embolism through the diploic veins — and the periosteum is removed and sent for histology. If that confirms involvement, or gross inspection suggests bone invasion, a thin, roughly one-millimeter layer of Mohs paste is applied directly to the exposed calvarium, after thorough informed consent since this use is off-label. The paste itself is essentially the historical formulation — about forty-seven percent zinc chloride by weight, plus Sanguinaria canadensis, with the old antimony trisulfide thickener now omittable since it's no longer available in pharmaceutical grade.

The wound is dressed, the patient stays supine for twenty-four hours, then rinses and continues local wound care, and comes back at six weeks for the key clinical test — tapping the skull with a periosteal elevator, where a tympanic, hollow sound indicates the bone has sequestrated and fully devitalized and is ready for removal. If it's not yet fixed, they simply reassess every two weeks until it is. Once ready, the devitalized outer table is removed with a small chisel and mallet under local anesthesia, submitted for decalcified permanent sections to confirm clear margins, and the resulting granulated bed is reconstructed with a skin graft or flap, or in smaller defects, allowed to heal by secondary intention or covered with a split-thickness graft.

The rationale the authors give for choosing chemical fixation over mechanical burring is that burring risks tumor seeding and gives you no histologic control, whereas zinc chloride achieves selective chemical fixation of only the involved bone, creates a natural cleavage plane for atraumatic removal, and lets you submit that bone for pathology. They note this same approach is extensible to extremity bones, not just skull. There's no results section or limitations analysis in the traditional sense since this is technique description, but the discussion is honest that this is off-label, requires multiple visits over roughly six weeks, and depends on careful patient selection and counseling.

Practical takeaway — this is a niche but genuinely valuable tool for a small subset of advanced calvarial tumors where you'd otherwise be reflexively referring out. It's not something you'll use often, but knowing the protocol, the air-embolism precaution of positioning the patient supine or prone during periosteal work, and the tympanic tap test as your readiness marker, could let you manage select bone-involving scalp tumors entirely in the outpatient Mohs setting rather than sending patients for OR-based resection.

Fourth and last article is a systematic review: "Intraoperative Interventions for Scar Optimization in Cutaneous Surgery," out of Emory. The background is simple — most scar-improvement strategies are traditionally applied after the scar has already formed, and this review asks what can be done during the surgery itself to shift the trajectory of healing. The methodology is a MEDLINE search using scar-related keywords, including both clinical trials and expert opinion pieces, restricted to English-language articles describing genuinely intraoperative interventions, with a PRISMA diagram documenting the search flow. Worth noting for methodology's sake — despite the "systematic review" label, this reads more like a structured narrative synthesis, since opinion pieces were explicitly allowed in and there's no formal quality grading or pooled effect size; that's a reasonable choice given how heterogeneous and sparse the intraoperative-intervention literature actually is, but it does mean you should treat the conclusions as a curated menu of options rather than a ranked, evidence-graded hierarchy.

Walking through what they found: on suture material, split-scar data comparing absorbable and nonabsorbable sutures — polyglactin versus nylon, in one facial-wound study, and separately in hand and wrist surgery — found no significant difference in cosmetic outcome or complication rates, so the traditional preference for nonabsorbable percutaneous sutures on cosmetic grounds isn't strongly evidence-backed. On suturing technique, running and interrupted sutures performed equivalently at six months regardless of location or surgeon experience, but subcuticular closure outperformed percutaneous closure in a large review of over two thousand wounds, particularly on the trunk, and setback sutures beat buried vertical mattress sutures in one study, with vertical mattress associated with more suture spitting and hypertrophic change. Wound eversion, long taught as essential dogma, didn't hold up under scrutiny — a split-scar study found no significant difference between planar and everted closures.

On nonsuture closure, cyanoacrylate glue reduces epidermal trauma and inflammation and patients often prefer its appearance, but it doesn't evert edges and has higher dehiscence rates in high-tension sites, so it's best reserved for smaller, lower-tension wounds or as an adjunct to subcuticular closure rather than a substitute in areas needing strong suture support.

Moving to exogenous interventions — botulinum toxin reduces tension on repairs overlying mimetic muscles, improves pliability, and works better with higher doses given earlier; type A and type B toxins performed equivalently, though type B has a faster onset that may be preferable for reducing tension earlier in healing, and onabotulinumtoxinA is favored among type A options for its lower ptosis risk. Intralesional triamcinolone showed a genuinely notable finding in the keloid excision literature — intraoperative dosing produced a six-month recurrence rate less than half that of postoperative dosing, even though cosmetic scores converged by six months, though this data is specific to keloids and shouldn't be generalized to other wound types. Laser ablation covers several modalities — pulsed carbon dioxide and Er:YAG lasers used for immediate post-Mohs second-intention healing improved contour matching and reduced depression at concave-to-convex transition sites, though outcomes didn't surpass formal surgical reconstruction; fractional carbon dioxide resurfacing applied before suturing improved elevation, discoloration, and erythema compared with suturing alone; and pulsed dye and laser-assisted skin healing lasers show promise but remain understudied specifically in the intraoperative window. The review's abstract also references platelet-rich preparations and mesenchymal stem cell applications as additional exogenous options, alongside dermabrasion for improving reepithelialization and contour blending, though the excerpt available doesn't detail those findings further.

The authors' bottom line is that no single intervention wins outright — selection should be individualized based on wound location, tension, and patient factors. The practical takeaway for your practice: treat the higher-confidence findings — subcuticular over percutaneous closure where feasible, judicious botulinum toxin for repairs overlying dynamic facial muscle, and intraoperative rather than delayed triamcinolone timing specifically for keloid-prone excisions — as reasonable to adopt now. Treat the rest — suture material choice, staples, glue, and the various laser modalities — as genuinely interesting adjuncts worth having in your toolkit for the right wound, but not yet backed by evidence strong enough to call them a new standard of care.

That wraps our four articles for March. To summarize the through-line: better-validated tools now exist to actually measure what matters to your patients after Mohs, a low-cost cooling adjunct may meaningfully ease keloid injection visits, a historical fixation technique still has a real role in bone-involving scalp tumors, and scar outcomes may be shaped as much by intraoperative choices as by anything done afterward. Thanks for listening, and we'll see you next month.