At Norwood 7, donor area assessment is the single most critical step before considering surgery. The remaining horseshoe band of hair is your entire surgical supply, and its density, laxity, and overall health determine whether a transplant can achieve meaningful results.
This article is for informational purposes only and does not constitute medical advice. Consult a qualified hair loss specialist before making any treatment decisions.
Why Donor Assessment Matters More at Norwood 7
Every hair transplant candidate needs a donor evaluation, but at Norwood 7 the stakes are higher than at any other stage. The bald area requiring coverage spans 180 to 250 square centimeters, yet the donor band is at its narrowest and may itself show thinning. Miscalculating the available supply leads to either an incomplete result or an over-harvested donor area that looks visibly depleted.
The safe extraction limit is 45% of donor follicles. Exceeding this threshold creates visible thinning in the donor zone, which can look worse than the original bald area because it appears unnatural. A thorough assessment ensures the surgeon stays within safe limits while maximizing coverage.
The Donor Zone at Norwood 7
At Norwood 7, the donor zone consists of the occipital band (back of the head, ear to ear) and potentially the temporal regions above the ears. This band is typically 8 to 12 centimeters wide and extends roughly 20 to 25 centimeters across the back of the head.
In earlier Norwood stages, this band is dense and robust. At Norwood 7, the band itself may have narrowed due to encroaching miniaturization from above. This narrowing reduces the total available graft count.
Key Metrics in Donor Assessment
Follicular Density
Measured in follicular units per square centimeter (FU/cm2), donor density is the foundation of surgical planning. Average scalp donor density ranges from 65 to 100 FU/cm2. At Norwood 7, density in the donor band may be lower than average due to:
- Natural aging and follicle attrition
- Miniaturization creeping into the upper edges of the donor zone (sometimes called "donor fringe thinning")
- Prior surgical extraction (if the patient has had previous procedures)
A trichoscopic scan at multiple points across the donor zone provides an accurate density map.
Scalp Laxity
Scalp laxity measures how easily the skin moves over the skull. This metric is primarily important for FUT (strip method), where the surgeon removes an elliptical strip of scalp and closes the wound. High laxity allows a wider strip with more grafts and a thinner scar. Low laxity limits strip width and may produce a wider, more visible scar.
For FUE, laxity is less critical but still relevant, as it affects how easily individual follicular units can be extracted from the skin.
Hair Shaft Caliber
Thicker hair shafts provide more visual coverage per graft. A patient with coarse, dark hair on a lighter complexion achieves better optical density than a patient with fine, light hair. Shaft caliber is measured in micrometers, with average being 60 to 80 micrometers.
Hair-to-Skin Color Contrast
Low contrast between hair and skin color (such as dark hair on dark skin, or blonde hair on light skin) naturally conceals thinner areas. High contrast (dark hair on pale skin) makes any density limitation more visible. This does not change the graft plan but affects expectations.
How Surgeons Perform the Assessment
Trichoscopy
Using a dermascope or digital trichoscope at 20x to 70x magnification, the surgeon maps follicular density across the entire donor band. Multiple measurement points (typically 8 to 12) provide a comprehensive density profile. This identifies areas of higher and lower density, allowing strategic harvesting.
Manual Palpation
The surgeon physically assesses scalp laxity by gently pinching and moving the scalp. This determines FUT feasibility and strip dimensions. The test is performed in multiple zones, as laxity varies across the occipital region.
Miniaturization Assessment
At each trichoscopy point, the ratio of terminal to miniaturizing hairs is calculated. If miniaturization exceeds 15-20% in portions of the donor band, those areas are unreliable for harvesting. Miniaturized donor hairs transplanted to the recipient area will continue to thin, defeating the purpose of surgery.
Total Graft Calculation
The surgeon combines density, area, and the 45% safe extraction limit to calculate the total available grafts. For example:
- Donor area: 200 cm2
- Average density: 75 FU/cm2
- Total follicular units: 15,000
- Safe extraction (45%): 6,750 grafts available
At Norwood 7, where 5,500 to 7,500 grafts are needed, this calculation determines whether the patient can achieve adequate coverage in two sessions or whether expectations must be adjusted.
Red Flags in Donor Assessment
Diffuse Unpatterned Alopecia (DUPA)
DUPA is a condition where hair loss affects the donor zone itself, not just the classic pattern areas. If the donor band shows significant miniaturization (more than 25%), the patient may not be a good transplant candidate at any stage. Transplanting miniaturizing donor hair produces temporary results that thin over time.
Prior Over-Harvesting
Patients who have had previous FUE procedures may have depleted portions of their donor zone. Moth-eaten or visibly thin patches in the donor area indicate over-extraction. The remaining density must be sufficient to support additional harvesting without visible damage.
Extremely Low Density
If baseline donor density falls below 50 FU/cm2, the total available graft supply drops significantly. At this density, even the 45% safe limit may not yield enough grafts for meaningful Norwood 7 coverage.
Alternative and Supplementary Donor Sources
Body Hair Transplant (BHT)
Beard, chest, and leg hair can supplement scalp donor supply. Body hair has different characteristics (finer, shorter growth cycles), so it is typically used for adding density to the mid-scalp and crown rather than building the hairline. An experienced BHT surgeon can add 1,000 to 3,000 supplementary grafts from body sources.
Scalp Micropigmentation (SMP)
SMP is not a donor source but it can simulate density between transplanted follicles. At Norwood 7, combining a transplant with SMP can create the illusion of fuller coverage without requiring additional grafts.
Getting Your Assessment
A comprehensive donor assessment requires an in-person consultation with an experienced hair restoration surgeon. For an initial evaluation, myhairline.ai's free AI assessment can help you understand your current Norwood stage and donor area characteristics before scheduling a clinical consultation.
For detailed information on each Norwood stage, see our Norwood scale classification guide. For pricing at this stage, see our Norwood 7 cost estimates.
Frequently Asked Questions
What does Norwood 7 look like?
Norwood 7 is the most advanced stage of male pattern baldness. Hair remains only in a narrow horseshoe-shaped band running from ear to ear around the back of the head. The entire top, frontal, mid-scalp, and crown areas are completely bald. The remaining band itself may show reduced density compared to earlier stages.
How many grafts do I need at Norwood 7?
Norwood 7 typically requires 5,500 to 7,500 grafts across two or more sessions for meaningful coverage. At an average of 2.2 hairs per graft, this provides 12,100 to 16,500 transplanted hairs. The safe extraction limit of 45% of the donor area sets the absolute ceiling on available grafts.
What are the best treatments at Norwood 7?
A multi-session hair transplant (FUE or FUT) combined with finasteride and minoxidil provides the best outcome at Norwood 7. Scalp micropigmentation (SMP) can supplement transplant density. Some patients combine body hair transplant (BHT) with scalp donor hair. Expectations must account for the finite donor supply at this stage.